• Issue 4 volume 68
  • Issue 3 volume 68
  • Issue 2 volume 68
  • Issue 1 volume 68
  • Supplement Issue volume 68
Page : 309-317

Title : Radiation Protection in Dentistry: Fundamental Concepts and Practical Approach

Author(s) : Pisha Pittayapat, Phonkit Sinpitaksakul, Ruben Pauwels, Soontra Panmekiate

Keyword(s) : Dentistry,Radiation protection,Radiology

Manuscript Type : Review Article (บทความปริทัศน์)

Page : 309-317

Radiographic imaging is an important diagnostic tool in dentistry. It offers useful information and data for
proper diagnosis, treatment planning and treatment follow-up. Despite the low level of ionizing radiation used, radiation
protection is necessary as evidence still suggests possible adverse effects that might be triggered by the low level
radiation. This review will discuss the fundamental concepts of the radiation protection specifically in dentistry:
justification, optimization and dose limits. Some practical approaches will be discussed and recommended for the
benefits of the dental society and patients. With the continuous development of imaging technology such as
cone-beam computed tomography and new digital sensors launched each year, evidence based approach is highly
recommended to develop clinical guidelines and recommendations. One must always keep in mind the fundamental
radiation protection principles and the As Low as Reasonably Achievable – ALARA principle.

Page : 318-328

Title : Concept of Neurogenic Inflammation During the Orthodontic Tooth Movements

Author(s) : Aunwaya Kaewpitak, Chidchanok Leethanakul

Keyword(s) : Orthodontic tooth movement,Calcitonin gene-related peptide (CGRP),Substance P,(SP) Bone remodeling

Manuscript Type : Review Article (บทความปริทัศน์)

Page : 318-328

Orthodontic tooth movement is related to the remodeling of paradental structures which are dental pulp,
periodontal ligament, alveolar bone, and gingiva. The changes occur in both clinical and cellular levels. The rates
of tooth movements depended on the characteristics of external force and biological responses of paradental
organs. Orthodontic force could modify periodontal ligament structures and the circulations. In these events, there
are several molecules playing the roles such as neurotransmitter, inflammatory cytokines, growth factors, and
arachidonic acid metabolites. This inflammatory orchestration could promote the paradental microenvironment for
bone resorption and formation. The previous studies have been focused on the mechanisms of various cells such
as fibroblast, endothelial cell, osteoblast, and osteoclast. However, this literature would like to depict the neurologic
mechanisms in order to remodel the paradental structures in orthodontic tooth movement.

Page : 329-338

Title : Breastfeeding and Early Childhood Caries

Author(s) : Nattanan Govitvattana, Siriporn Songsiripradubboon

Keyword(s) : Breast milk,Breastfeeding behaviors,Dental caries

Manuscript Type : Review Article (บทความปริทัศน์)

Page : 329-338

Human breast milk is still the best nutritional source for the baby especially in the first year of life. Human
breast milk is composed of immunologic compounds and proteins that were shown to interfere and inhibit bacterial
adhesion and colonization. However, it also contains lactose, the main sugar in the human breast milk, that
Streptococcus mutans can utilize and produce acid in dental plaque. Many studies have tried to find the relationship
between breastfeeding and dental caries. In last decades, breastfeeding behaviors and dental caries have been
studied extensively. The results often varied depending on the criteria used for oral examination, ages of the children
studied, definitions of breastfeeding patterns and other confounding factors included in each studies. Some studies
found a relationship between breastfeeding and dental caries, some studies failed to find the relationship, while
some studies found the protective effects against dental caries from breastfeeding. So far, the relationship between
breastfeeding and dental caries is still inconclusive. Thus, the objective of this review article is to present the

Page : 339-345

Title : Corticotomy-assisted Orthodontic Treatment in Bimaxillary Protrusion Patients

Author(s) : Bancha Samruajbenjakun, Navarat Voravongsagul

Keyword(s) : Bimaxillary protrusion,Corticotomy,En-masse retraction

Manuscript Type : Review Article (บทความปริทัศน์)

Page : 339-345

Corticotomy-assisted orthodontic treatment is an option to accelerate orthodontic tooth movement. It
also can reduce risks of root resorption, dehiscences and fenestration; increase stability after orthodontic treatment;
and expand envelope of tooth movement. In bimaxillary protrusion patients, corticotomy-assisted en-masse retraction
can improve malocclusions and prevent side effects from anterior tooth movement beyond the anatomical limit.
After a corticotomy, the decreased bone density effects the center of resistance of anterior teeth. The mechanics
for en-masse retraction and force systems should be considered for desired anterior teeth movement and control
of the posterior segment.

Page : 346-359

Title : Simultaneous Maxillo-Mandibular Unit Distraction Osteogenesis Treatment of Facial Asymmetry for Hemifacial Microsomia Using Multiple Internal Distraction Device

Author(s) : Thongchai Nuntanaranont, Wipapun Ritthagol, Anupong Suraseraneewong

Keyword(s) : Distraction osteogenesis,Hemifacial microsomia,Intraoral distraction device

Manuscript Type : Case Report

Page : 346-359

Two cases of facial asymmetry with diagnosis of hemifacial microsomia treated by three internal distractors
to correct occlusal canting, shorten ramus and facial asymmetry were presented. The initial evaluation showed
hemifacial deficiency, occlusal and lip commissure canting. All of the clinical data showed characteristic of hemifacial
microsomia type 2 according to Pruzunsky’s classification. Three intraoral distractors were placed following a Le
Fort I osteotomy, left horizontal ramus osteotomy and right intraoral vertical ramus osteotomy. The modified
Le Fort I osteotomy was designed for the direction of distraction by clockwise rotation with anterior nasal spine as
center of rotation. Left side distractors were activated to lengthen left site segment but the right side distractor was
activated to compress right segment. Advancement of 6 mms of left ramus and 3.75 mms of left maxilla were
obtained within 2 week. In the completion distraction phase, both occlusal canting and shorten left ramus were
obtained. After the consolidation period, the distractors were removed under general anesthesia without any
complication. Furthermore the right side angle reduction and mandibular buccal osteotomy, advancement genioplasty,
left mandibular body augmentation with autogenous bone graft and nose augmentation with silicone material were
performed to improve the final esthetic. Long term post-operative follow up revealed the optimal occlusion with
significant improving in facial symmetry without any skeletal relapse detected.

Page : 360-369

Title : Efficacy of Coconut Oil and 0.12 % Chlorhexidine Mouth Rinses in Reduction of Plaque and Gingivitis: A Two-Week Randomized Clinical Trial

Author(s) : Darunee Owittayakul, Kanjana Palee, Sakornratana Khongkhunthian, Wirongrong Langkapin, Phenphichar Wanachantararak

Keyword(s) : Chlorhexidine,Coconut oil,Gingivitis,MouthRinse,Oil-pulling

Manuscript Type : Original Article (บทวิทยาการ)

Page : 360-369

The objective of this study was to compare the clinical effects of coconut-oil and 0.12 % chlorhexidine
(CHX) on the reduction of plaque and gingivitis. Forty healthy undergraduate dental students were randomly allocated
into two groups of 20 participants each: control group (0.12 % CHX) and experimental group (coconut oil). All participants
were instructed to rinse their mouthdaily strictly and consistently for two weeks. Oral examination, plaque index
(PI) and gingival bleeding index (GBI) were performed at baseline and on day 14. At the end of the study, satisfaction,
adverse effects and a desire to continue mouthrinse usage were recorded by questionnaires. Thirty-five participants
completed the trial. The results revealed that there were significant reductions in PI and GBI between baseline and
day 14 in both groups (p=0.001; p<0.001). The mean percentage reductions in PI and GBI in each group were; 0.12 %
CHX (41.05 % and 33 %, respectively) and coconut oil (29.43 % and 36.35 %, respectively). There was no significant
difference in the percentage reductions in PI and GBI between the two mouthrinses. Coconut oil had significantly
higher overall satisfaction scores, greater satisfaction scores for taste and fewer side effects (p=0.03, p<0.001, p=0.003,
respectively). However, the numbers of participants who desired to continue using coconut oil were significantly
lower than those who desired to use CHX because the long rinsing duration for coconut oil was an obstacle. Coconut
oil can be considered as an alternative mouthrinse in reducing PI and GBI in participants with gingivitis because of
its fewer side effects.

Page : 370-380

Title : Effect of Surface Treatments on Microtensile Bond Strength of Bis-acryl Resin Provisional Restoration and Self-curing Acrylic Resin

Author(s) : Umaporn Vimonkittipong, Apittita Tangjaren, Kitinun Tissanavasoontra, Rus-ake Tantisawat, Waritta Mangkorn, Winwan Vilaiwan, Chanyanut Wannasuknukul

Keyword(s) : Bis-acryl resin,Self-curing acrylic resin,Microtensile bond strength,Single bond universal adhesive

Manuscript Type : Original Article (บทวิทยาการ)

Page : 370-380

The aim of this study was to investigate the effect of surface treatments on the microtensile bond strength
of bis-acryl resin provisional restoration (ProtempTM4) and self-curing acrylic resin (UnifastTMTRAD). Specimens of
cylindrical bis-acryl resin blocks 10 millimeters in diameter and 5 millimeters in height were prepared and stored
in artificial saliva at 37-degree celsius for 14 days. The specimens were randomly divided into 3 groups (n=20) according
to the types of surface treatments: (I) Sandblast with Al2O3 50 micron (2) Single bond universal adhesive (3) Untreated
group. After bis-acryl resin blocks were prepared according to their group of surface treatment, blocks were adhered to self-curing acrylic resin and cut into dump-bell shape 1 mm2.Each group was divided into 20 pieces. Microtensile
bond strength test was performed by using a universal testing machine. The data were statistically analysed by
using one-way ANOVA and Tukey HSD at significance level of 0.05. The fractured surfaces were examined under
stereomicroscope to classify the mode of failure and examined surface by scanning electron microscope (SEM). The
study showed that the highest microtensile bond strength was observed in sandblast group with statistically significant
differences of highest average bond strength compared to other groups. The study revealed no statistically significant
differences between untreated group and single universal adhesive group. The modes of failure were primarily of
cohesive type for both bis-acryl resin and self-curing acrylic resin. The study concluded that surface treatment with
sandblast technique on bis-acryl resin prior adhering to self-curing acrylic resin provided the highest microtensile
bond strength, which was significantly higher than other groups.

Page : 381-393

Title : Effectiveness of Audit and Feedback on Oral Health Performance in Qualified Well Child Clinic (WCC) with Full Time Dental Nurse at Sub-district Health Promoting Hospital in Phang Nga: Randomized Controlled Trial

Author(s) : Thanakorn Saringkanchayathawat, Sukanya Tianviwat

Keyword(s) : Audit and feedback,Caries risk assessment,Parental oral health care behavior,Dental nurse,Randomized controlled trial

Manuscript Type : Original Article (บทวิทยาการ)

Page : 381-393

The main purpose was to study the effectiveness of audit and feedback on oral health performance in
qualified Well Child Clinic (WCC) with full time dental nurse at Sub-district Health Promoting Hospital. This study
was a double blind randomized controlled trial. The samples consisted of 14 dental nurses who worked at Sub-district
Health Promoting Hospital (7 in control and 7 in intervention groups). Seven hundred and fifty two children and
their guardians were included (372 pairs in control and 380 pairs in intervention groups). The intervention group
received audit and feedback both at group level and confidential individual level. The tailor-made solving problem
plan was developed after feedback. The dental nurses’ performance evaluated by chart auditing for the coverage
and the accuracy of caries risk assessment. The outcome evaluation was oral health care behavior of guardians and
oral cleanliness. Structure questionnaire interviewing among guardians was used for oral health care behavior.
Dental examination was conducted for oral cleanliness. The evaluation was implemented two times; at baseline
and 6 months after intervention. The mean ages at baseline of children among control and intervention groups
were 22.4±7.8 and 20.8±6.6 months, respectively. At 6 months after intervention, the number of existing children
were 642 (85.4 %) with mean age 27.5±7.1 months and 26.8±6.4 months among control and intervention groups,
respectively. There were statistically significance between both groups in the coverage and the accuracy of caries
risk assessment by dental nurses, oral health care behavior and oral cleanliness of guardian and their children. In
conclusion, audit and feedback improved the dental nurses’ performance, parental oral health care behavior and
children oral cleanliness.

Page : 394-401

Title : Comparison of Space Analysis from Computer-based Digital Model and Plaster Model

Author(s) : Supanee Suntornlohanakul, Tatchatam Raksin

Keyword(s) : Digital model,Impression scanning,Orthodontics,Space analysis

Manuscript Type : Original Article (บทวิทยาการ)

Page : 394-401

This study intended to determine the differences of space analysis in four groups each with a different
level of crowding severity using digital models of impressions and compared with the plaster models. One hundred
and twenty upper and lower plaster models were divided into four groups according to the crowding severity: group
1, no crowding; group 2, lack of space less than 2 mm; group 3, lack of space 2–4 mm; and group 4, more than 4
mm. These models were converted to digital models by impression scanning using the 3Shape R700™ scanner.
Tooth size and segmental arch length measurement were performed on the plaster models using a digital caliper
with a scale precision of 0.01 mm and digital models using the 3Shape OrthoAnalyzer™ software. Space discrepancy
of each study model was calculated. Independent t-test and Wilcoxon rank-sum test were used to compare sum
of tooth size, segmental arch length, and space discrepancy. No statistically significant differences were found between
the plaster and digital models for sum of tooth size, segmental arch length or space discrepancy measurement in
any group of crowding. The use of digital models obtained from the 3Shape R700™ scanner appears to be acceptable
in tooth size, segmental arch length, and space discrepancy measurements.

Page : 402-412

Title : Voids of Bulk-fill Resin Composite Restoration in Class II Cavity

Author(s) : Chinnadate Jira-arnon, Chaiwat Maneenut

Keyword(s) : Restoration,Voids,Bulk-fill resin composite,Micro-computed tomography,Class II cavity

Manuscript Type : Original Article (บทวิทยาการ)

Page : 402-412

The aim of this study was to evaluate voids formation in Class II cavity restored with different placement
methods of bulk-fill resin composites using micro-computed tomography (micro-CT). Standardized Class II cavities
were prepared in 40 extracted human premolars which were divided into 4 groups. Group1: one bulk placement
with syringe type; Group2: incremental placement with syringe type; Group3: one bulk placement with injection
capsule type; Group4: one bulk placement with injection SonicFill Handpiece type. Percent of voids (% Void) in
restored cavity was evaluated with micro-CT after storage in 100 % relative humidity at 37 degrees Celsius for 24
hours. Statistical analysis was done using One-way ANOVA and Tukey post hoc test at confidential level of 95 %.
Results: Percent of voids in group 2 (1.62 %) was significant higher (p = 0.05) than the other groups (0.49 %, 0.33 %
and 0.21 %, respectively). Conclusion: Incremental placement created the highest voids when restore Class II cavity
with bulk-fill resin composite.

Page : 413-419

Title : Effect of Corticotomy Patterns on the Center of Resistance Location of the Upper Six Anterior Teeth During En Masse Retraction: Finite Element Analysis

Author(s) : Bancha Samruajbenjakun, Tanes Ouejiaraphant, Ekachai Chaichanasiri

Keyword(s) : Center of resistance,Corticotomy pattern,En masse retraction,Finite element analysis

Manuscript Type : Original Article (บทวิทยาการ)

Page : 413-419

To determine the center of resistance location of six maxillary anterior teeth during en masse retraction
after combination with different corticotomy patterns. Five finite element models were constructed from CBCT.
Standard brackets were passively positioned on maxillary anterior teeth at the center in mesiodistal dimension and
3 mm vertically from the cusp tip. The power arm was set mesial to the canine bracket and the mini-implant was
placed between the upper second premolar and the first molar. Five decorticated bone patterns were created,
the patterns started at 1 mm above the crest of the alveolar bone of the upper first premolar to central incisor areas.
The upper anterior teeth were retracted from the power arm to the mini-implant. The center of the resistance
location was determined by varying the force locations parallel to the occlusal plane until bodily movement of the
upper anterior teeth was obtained. The center of resistance in all models was located at the same 10.8 mm distance
apically from the middle of the bracket slot in the mesiodistal dimension or 13.8 mm apically from the incisal edge.
Different corticotomy patterns did not change the center of resistance location of the upper anterior teeth in en
masse retraction.

Page : 420-427

Title : Effect of Xylitol Varnish on Enamel Erosion In Vitro

Author(s) : Siripa Kijanukul, Rangsima Sakoolnamarka

Keyword(s) : Demineralization,Dental Erosion,Fluoride varnish,Soft drinks,Xylitol varnish

Manuscript Type : Original Article (บทวิทยาการ)

Page : 420-427

The aim of this study was to compare the property of two different concentrations of xylitol varnish and
fluoride varnish on enamel erosion from soft drink. Enamel specimens were prepared from 25 human premolars.
The teeth were sectioned mesial-distally to obtain buccal and lingual halves. The buccal and lingual surfaces were
polished to obtain flat enamel surfaces 3 millimeters in diameter. Nail varnish was applied to the polished surface
except for the test area. The specimens were randomly divided into following treatments (n=10): Group 1 - negative
control, Group 2 - fluoride varnish, Group 3 – 20 % xylitol varnish, Group 4 – 30 % xylitol varnish and Group 5 - placebo varnish. The varnishes were applied to enamel surfaces before demineralization and on the fifth day of
demineralization. Then, the specimens were demineralized by immersion in soft drink for five minutes for ten days.
Enamel volume loss was measured by contact profilometer. The data were analyzed statistically using One-way
ANOVA and Tukey’s post-hoc test with the level of significance at p<0.05. The mean enamel volume losses (cubic
millimeters) were not significantly different in the negative control group (0.0121±0.0019) and the placebo varnish
group (0.0117±0.0015). The mean enamel volume loss of the 20 % xylitol varnish group (0.0084±0.0004) showed
more volume loss than the fluoride varnish group (0.0070±0.0007) with no statistically significant difference. The 30 %
xylitol varnish group showed the lowest mean enamel volume loss (0.0055±0.0005) with statistically significant
when compared to other groups. From the result of this study, 20 % xylitol varnish and fluoride varnish showed no
significantly difference in reducing enamel erosion by soft drink. Whereas, 30 % xylitol varnish showed the highest
performance among all treatment groups.

Page : 197-203

Title : A Comparison of Centering Ability of One Shape and Reciproc in Simulated Severely Curved Canals

Author(s) : Thalerngsak Samaksaman, Pattama Chailertvanitkul, Soontaree Boonnadee, Phiranat Chongrak

Keyword(s) : Centering ability,Severely curved canals,Rotary instrument,Reciproc,One shape

Manuscript Type : Original Article (บทวิทยาการ)

Page : 197-203

The aim of this in vitro study was to compare the centering ability of 2 single file systems; One Shape and Reciproc after root canal preparation in 34 acrylic resin simulated severely curved canals. These two instruments use different motions, One Shape uses continuous rotation while Reciproc uses reciprocating motion. Indian ink and methylene blue dye were used to stain the canals before and after root canal preparation. Photographs were taken by dental operating microscope and the pictures superimposed using Adobe Photoshop CS2.0. Canal transportation was defined as the distance (in millimeters) from the pre- to the post-instrumented canal wall measured on both the outer and inner curve of the simulated canal. Measurement of the distances was done in a perpendicular plane to the resin block’s long axis at 10 positions with 1 millimeter increment. Statistical analysis was performed using T-test and Mann-Whitney U test at the 95 % confidence interval. Results found no statistically significant difference in the mean centering ratio at any level (p=0.998). In conclusion, the centering ability of One Shape and Reciproc were not different.

Page : 204-217

Title : The Relationship Between Admissions Criteria and Academic Performance of Dental Students with Prior Bachelor Degree (“Newtract”) at ThammasatUniversity

Author(s) : Nattira Suksudaj, Chanikarn Auttapunya, Passupang Veerapeindee, Attarat Sittisart

Keyword(s) : Academic performance,Admissions criteria,Dental students

Manuscript Type : Original Article (บทวิทยาการ)

Page : 204-217

The purpose of this study was to examine the associations among admissions criteria and academic
performance of “Newtract” dental students at Thammasat University. This study consisted of a retrospective analysis
of 242 students who enrolled in Thammasat dental program between 1996 and 2010. Data about admissions criteria
and academic records of the students were obtained from the Office of the Registrar. Multiple regression analyses
were used to identify the best combination of predictors in the regression equation. As two groups of admissions
criteria were used during the time period of the study, the regression analyses were then divided into two groups,
Group 1: including eight predictors, i.e., predental GPAX, scores on six subjects & manual dexterity; and Group 2:
including four predictors, i.e., predental GPAX and scores on three parts of the Scholastic Assessment Test (SAT).
Three academic performance categories were considered: GPA for each academic year, overall GPAX and preclinical
performance in restorative dentistry, endodontology, and prosthodontics courses. Predental GPAX
correlated positively with GPA in each level of the dental curriculum, and overall GPAX in both groups (p<0.05). In
Group 1, the best model for predicting academic performance is the model with four predictors, i.e., predental
GPAX, scores on biology, physics and English, these four predictors accounted for 31 % (R2=0.31) of variance in the
predicted values for second year GPA. In Group 2, the best model for predicting second year GPA (R2=0.33) and
dental GPAX (R2=0.32) is the model with one predictor, i.e., predental GPAX. Other models show significant correlation
between other admissions criteria and academic performance, they accounted for 7-26 % of variance in predicted
values for the academic outcomes. Overall, the findings suggest that there is a positive relationship between predental
GPAX and scores of some subject tests with academic performance, however, the predictive ability is weak.

Page : 218-229

Title : A Survey of Knowledge, Attitude and Practice Regarding Hand Hygiene amongThai Dentists

Author(s) : Pratanporn Arirachakaran, Korapin Mahatumarat, Natcha Mahatumarat, Keeratika Wongtim, Chanisa Huangwong

Keyword(s) : Practice,Knowledge,Attitude,Hand hygiene,Alcohol hand rub

Manuscript Type : Original Article (บทวิทยาการ)

Page : 218-229

The objective of this study is to compare knowledge attitude and practice of hand hygiene including alcohol
hand rub use among dentist groups who had different number of years in current practice by gathering the data
from 149 returned questionnaires. In each category, the average scores were compared among 3 groups of dentistswho had been in practice for 0-10 years, 11-20 years and 21-30 years. The results were found that no statistical
significant differences in the average total scores among groups in knowledge attitude and practice category (p<0.05).
However, the 21-30-year group had significantly lower average score than the 11-20-year group in hand hygiene
practice category (p<0.05) and the 0-10 year group had significantly lower average score than other groups in alcohol
hand rub attitude category (p<0.05). In summary, number of years in practice has no significant effect on average
total scores among groups in knowledge attitude and practice category. However, dentist who has been working
for longer time tends to achieve less score in hand hygiene practice while dentist who has been working for shorter
time tends to achieve less score in alcohol hand rub attitude.

Page : 230-236

Title : Sex Determination Using Canines in Thais

Author(s) : Natchalee Srimaneekarn, Jirattikarn Kaewmuangmoon, Tawepong Arayapisit

Keyword(s) : Sex determination,Logistic regression,Canine,Intercanine width

Manuscript Type : Original Article (บทวิทยาการ)

Page : 230-236

The objective of this study is to establish the sex determination tool using canines in Thais. The samples
in this study were 266 Thai people, including 140 females and 126 males with age 20.05±1.47 years old. The
mesiodistal width of four canines and the upper and lower tip-to-tip intercanine width were measured. The differences
of all distances between sex were determined by the independent samples t-test with 0.05 significant level. Simple
and multiple logistic regression analyses were used to establish the sex determination equations for single and
multiple variables, respectively. Statistically significant differences between sex were found in all measurements.
Moreover, the sex determination equation with one variable for each measurement was statistically significant.
However, when all measurements were investigated together, only lower left canine and upper intercanine widthwere included in the sex determination equation with 25.1 % R2, and the odd ratio were 4.912 and 1.280 for lower
left canine and upper intercanine width, respectively. Moreover, the accuracy of novel equation is 68.18 %. In
conclusion, canine can be another tool to determine sex together with other factors.

Page : 237-248

Title : Effect of Remineralization on Color Change of Bleached Tooth

Author(s) : Panita Suttisakpakdee, Sirivimol Srisawasdi

Keyword(s) : Color relapse,Tooth bleaching,Remineralization,CPP-ACP

Manuscript Type : Original Article (บทวิทยาการ)

Page : 237-248

The aim of this in vitro study was to investigate the effect of remineralization and time on the color and
microhardness change of bleached teeth using 10 % carbamide peroxide (CP) and 40 % hydrogen peroxide (HP).
Seventy-two 6x6x2 mm3 enamel slabs were prepared from human premolars. The specimens’ color and Vickers’
microhardness were recorded at baseline (T0). The specimens were divided into six groups: twelve specimens per
group. Two groups were treated with 10 % CP with or without casein phosphopeptides and amorphous calcium
phosphate (CPP-ACP) (10 % CP and 10 % CP/CPP-ACP, respectively), two groups were treated with 40 % HP with or
without CPP-ACP (40 % HP and 40 % HP/CPP-ACP, respectively), one group received no bleaching (CON) and
another group received only CPP-ACP treatment without bleaching, (CON/CPP-ACP). The CPP-ACP groups were
treated with CPP-ACP twice daily for five minutes for seven days after completing their respective protocol. The
color change and Vickers’ microhardness were recorded at three time points after treatment; one day (T1), two
weeks (T2), and one month (T3). After one month, the tooth color changed (ΔE) in all groups at every time point;
however, significant ΔE was found only at T3 for the 10 % CP and the CON/CPP-ACP groups (p<0.05). Microhardness
tended to decrease from the baseline (T0) value at each time point. There were significant differences between
time points in microhardness (ΔVHN) in the 40 % HP, CON, and CON/CPP-ACP groups. A relationship between ΔE
and ΔVHN was found in the 10 % CP and 10 % CP/CPP-ACP groups. In summary, tooth whiteness decreased in the
10 % CP group from T1 to T3. CPP-ACP can prevent color relapse in the 10 % CP/CPP-ACP and CON/CPP-ACP groups.
Microhardness improved in the 10 % CP/CPP-ACP group compared with the 10 % CP group at T3. Both tooth whiteness
and microhardness were stable for at least one month when CPP-ACP was used as an intervention in the 10 % CP/
CPP-ACP group.

Page : 249-255

Title : Evaluation of 20 degree Shifted Radiographs in Endodontic Treatment

Author(s) : Piyanuch Karnasuta, La-ongthong Vajrabhaya, Suwanna Korsuwannawong, Orachorn Thongburan, Nuttapat Suntharapa, Supussorn Netpheng, Teerada Wuttiprasittipol

Keyword(s) : Endodontic treatment,Radiograph,Twenty-degree angulation

Manuscript Type : Original Article (บทวิทยาการ)

Page : 249-255

The aim of this study was to evaluate the frequency of root canal separation on radiographs of mandibular
molars taken for determining endodontic treatment working length using a 20o mesial (M) or distal (D) shift jig compared
with a perpendicular (0o) angle. Radiographs of 42 human mandibular molars were taken at a horizontal angle of
0o, 20o M shift, or 20o D shift to the tooth. The radiographs were evaluated by two examiners. Seventy-one percent
and 73 % of the 20o M shift radiographs were deemed acceptable (separated roots) by the first and second examiner,
respectively. In contrast, 54 % and 64 % of the 20o D shift radiographs were acceptable to the first and second
examiner, respectively. The strength of agreement from both examiners was at a high level of 0.804-0.904. The
percentage of acceptable M and D shift radiographs for each examiner were similar (P>0.05) and significantly higher
compared with the 0o x-ray beam angle (P<0.05). Radiographs taken using either the 20o M or D shift jigs are more
likely to have distinct mandibular molar root canal separation when determining the working length for root canal
treatment compared with 0o images. The advantage of these jigs is the precise determination of the shifted
radiograph angle.

Page : 256-269

Title : Effectiveness of Motivational Interviewing for Improving Bedridden ElderlyPeople’s Oral Health by the Family Caregiver: A Randomized Controlled Trial

Author(s) : Jaranya Hunsrisakhun, Arnut Martragul, Achara Watanapa

Keyword(s) : Bedridden elderly people,Caregiver,Motivational interviewing,Oral health

Manuscript Type : Original Article (บทวิทยาการ)

Page : 256-269

The proposes of this study were to compare the effective on promoting oral health care for bedridden
elderly people between applying motivational interviewing (MI) and conventional dental health education (CDE).
This study was a quantitative part of a mix method based on an explanatory sequential design. Sixty-two elders
and family caregivers in Krabi Province were randomly assigned to an intervention or a control group. In the 3
months’ follow up, 28 and 26 participants remained in the intervention and control group, respectively. At baseline,
there were no significant differences between the intervention and control groups on levels of plaque index, oral
health behavior care for elders as well as general characteristics of elders and caregivers except elder’s diet types,
number of permanent teeth, caregivers’ education and age (p<0.05). At 3 months’ follow-up, the proportion of
appropriate oral health care for the elders in the intervention group was significantly different from the control group (p<0.05) such as toothbrushing with fluoride toothpaste, rinsing with mouthrinse, frequency on oral hygiene
care, oral hygiene and oral status-check after oral hygiene care. Furthermore, level of positive attitudes towards oral
health care was increased at 3 months’ follow-up in an intervention-group. There were no significant differences
of level of plaque index between groups, but dental plaque index of each group decreased comparing with their

Page : 270-278

Title : The Effects of Cervical Lesion, Endodontic Access, and Resin Composite Restoration to the Fracture Resistance and Fracture Pattern of MaxillaryPremolars

Author(s) : Thanomsuk Jearanaiphaisarn, Annop Opasatian

Keyword(s) : Cervical lesion,Endodontic access,Fracture resistance,Maxillary premolar,Resin composite

Manuscript Type : Original Article (บทวิทยาการ)

Page : 270-278

Deep cervical lesion is one of the bacterial tracts that can cause pulpal infection. Although, most
endodontically treated posterior teeth are susceptible to fracture due to marginal ridge loss, it is doubtful about
the effect of deep cervical loss to fracture resistance and the proper restoration for these teeth. This study
investigated the effect of wedge-shaped cervical tooth loss and/or endodontic access and resin composite restoration
on the fracture resistance and fracture pattern of maxillary premolars. Sixty-five intact extracted upper premolars
were divided into 5 groups (n=13) with different amounts of tooth structure loss: 1) Intact tooth (IT), 2) Cervical
lesion (CL), 3) Endodontic access (EA), 4) Cervical lesion and Endodontic access (CLEA), and 5) Cervical lesion,
Endodontic access, and Resin composite restoration (CLEAR). Each specimen was vertically loaded on its occlusal
surface using a universal testing machine until fracture occurred. Fracture resistance was analyzed using One-way
analysis of variance, followed by the Tukey HSD test (α=.05). The fracture patterns were determined by visual
inspection. The EA and CLEA group presented significantly lower fracture resistance than the IT groups. The fracture
resistance of The CLEAR group was not significantly different from that of the IT group. Most teeth in the IT, CL and
CLEAR group fractured above cemento-dentinal junction (CEJ) but in the EA and CLEA groups, fracture under CEJ
were prevalent. In conclusion, endodontic access significantly reduced the fracture resistance of maxillary premolars,
especially when combined with a cervical lesion. Resin composite restoration increased the fracture resistance to
approximately that of the intact tooth.

Page : 279-287

Title : The Effectiveness of Oral Health Education Program in Late ElementarySchool Students in Nongchok District, Bangkok

Author(s) : Nattanan Govitvattana, Siriporn Songsiripradubboon

Keyword(s) : Peer,Knowledge scores,School students,Oral health education,Plaque scores

Manuscript Type : Original Article (บทวิทยาการ)

Page : 279-287

The aim of this study was to compare the effectiveness of different oral health education (OHE) programs
in late elementary school students in Bangkok. One hundred and fifty-four students were divided into 3 groups:
Group 1 was instructed OHE by school health teacher, Group 2 was instructed OHE by school health teacher in
combination with peer modeling activities, Group 3 served as a control group which did not receive any interventions.The teacher used OHE instructor guide which comprised of dental caries, gingivitis, and tooth cleaning technique.
Peer models served as a model and motivated other students to brush their teeth during the lunch break. Knowledge
scores and plaque scores were assessed in all students before OHE program and 3 months afterward. The knowledge
was evaluated by multiple choice questions while plaque level was detected by erythrosine dye and measured
with soft debris index. The results indicated that post-test knowledge scores increased statistically significant in both
OHE groups (p<0.001) when compared with pre-test knowledge scores and the control group (p<0.001). However,
there is no statistically significant difference between both OHE groups. Plaque scores decreased statistically significant
only in peer group when compared with baseline (p<0.001). The results suggested that OHE by school health
teacher was not enough in term of changing tooth brushing behavior when using plaque scores as an indicator. The
participation of peer models in OHE program increased the effectiveness of OHE in school.

Page : 288-301

Title : The Longevity of Ceramic veneers: Clinical Evaluation of Mechanical, Biologicand Aesthetic Performances of Ceramic Veneers, a 7-year Retrospective Study

Author(s) : Chalermpol Leevailoj, Rapeepan Monaraks

Keyword(s) : Ceramic veneer,Clinical evaluation,Longevity,Porcelain laminates veneer,Success rate

Manuscript Type : Original Article (บทวิทยาการ)

Page : 288-301

The objective of this study was to evaluate the mechanical, biological and aesthetic performance of
ceramic veneers after 5 to 7 years of service. The ceramic veneer restorations were clinically examined using a
modified criteria of the United States Public Health Service (USPHS) and World Dental Federation (FDI). Clinical
evaluation was performed by two clinicians during maintenance appointments between September 2016 and August 2017. Intra-examiner and inter-examiner reliability was evaluated by calculating the intraclass correlation coefficient and by inter-examiner calibration. The results were analysed by the Kaplan-Meier survival estimation method and log-rank test at a 95 % confidence level. One hundred and sixty-three veneers [a mean clinical service of 68.1±0.66 months] were examined. Overall survival rate of the veneer restorations was 97.5 % with 2.5 % (four veneers)
presenting clinically unacceptable problems, such as fracture and debonding. Caries were not detected in any teeth.
Radiographic examination found the development of a periapical lesion in one patient after veneer placement.
Veneer placement in premolars showed a higher failure rate than other dental regions. Most patients were
comfortable with their restorations and satisfied with the aesthetic results. Ceramic veneers demonstrated a high
survival rate with most failure cases resulting from fracture and debonding.

Page : 302-308

Title : Scanning Electron Microscopic Study of the Cleaning Ability of Various Root Canal Irrigants in Primary Teeth

Author(s) : Siriruk Nakornchai, Panit Banditsing, Duangrat Owattanapanich

Keyword(s) : Chlorhexidine,Irrigants,Sodium hypochlorite,Pulpectomy,Primary teeth

Manuscript Type : Original Article (บทวิทยาการ)

Page : 302-308

Cleaning a root canal is important for successful endodontic treatment. Currently, several irrigants have
been suggested for primary teeth. The objective of this study was to evaluate the cleaning ability of various root
canal irrigants in primary teeth. Forty-four primary anterior teeth with periapical lesion were selected and divided into
four groups using different root canal irrigants: 1 % sodium hypochlorite; 2 % chlorhexidine liquid; 2 % chlorhexidine
gel and normal saline. The roots were prepared for SEM analysis. Four areas of each one third were examined and
scored. The data were analyzed using Kruskal Wallis H and Friedman test. Result showed that the best cleaning
was found in the coronal third and the worst in the apical third (P<0.01). Cleaning result of chlorhexidine gel did
not significantly differ from that of sodium hypochlorite. In addition, the cleaning ability of chlorhexidine gel was
better than that of chlorhexidine liquid in all root thirds. No significant difference was observed between chlorhexidine
liquid and normal saline in any root thirds. It was concluded that the least effective cleaning ability of all irrigants
were found in the apical third, chlorhexidine gel showed better cleaning than chlorhexidine liquid and normal
saline, but did not differ from sodium hypochlorite.

Page : 92-98

Title : Importance of Clinical Parameters to Predict the Periodontal Disease Progression During Supportive Periodontal Therapy

Author(s) : Sirikarn P. Arunyanak, Kamolchanok Kamolnarumeth

Keyword(s) : Bleeding on probing,Disease progression,Probing pocket depth,Supportive periodontal therapy,Suppuration

Manuscript Type : Review Article (บทความปริทัศน์)

Page : 92-98

Objectives of supportive periodontal therapy are to maintain healthy periodontium and prevent periodontal disease progression by regular recall appointments. Clinical parameters recorded during visits can identify current periodontal status and, moreover, can predict disease progression in the future. It is useful for treatment planning especially in risk sites which are possible to have further loss of clinical attachment. This review article gathers information regarding the importance and predictability in disease progression of three clinical parameters including bleeding on probing, suppuration, and probing pocket depth during supportive periodontal therapy. Each clinical parameter can predict disease progression in different levels. To date, no clinical parameter can forecast the attachment loss accurately.

Page : 99-106

Title : Sialadenoma Papilliferum of the Palate: A Case Report

Author(s) : Marnisa Sricholpech, Aroonwan Lam-Ubol, Chanchai Wongchuensoontorn, Sorasun Rungsiyanont

Keyword(s) : Minor salivary gland,Palate,Sialadenoma papilliferum

Manuscript Type : Case Report

Page : 99-106

Sialadenoma papilliferum (SP) is a rare benign salivary gland tumor. Mostly, it occurs in association with minor salivary glands, especially at the posterior palate. The typical clinical features of this tumor are asymptomatic, slow growing, broad-based papillary projections of the oral mucosa. Here, we report a case of SP at the posterior palate of a 57-year-old woman. After incisional biopsy, complete excision of the tumor was performed. Histopathological examination showed parakeratinized stratified squamous epithelium which exhibits exophytic papillary projections along with underlying fibrocollagenous vascular connective tissue containing ductal structures lined by inner columnar cells and outer cuboidal cells. Based on these findings, the final diagnosis of SP was given. No recurrence was observed at 12 months follow-up. Reviews of previous case reports, clinical and histopathological differential diagnosis are discussed.

Page : 107-120

Title : Artificial Eruption of Complicated Tooth Impaction Cases. (A report of 2 cases)

Author(s) : Noppadol Chanpongsaeng

Keyword(s) : Complicated,Tooth impaction,Artificial eruption

Manuscript Type : Case Report

Page : 107-120

Artificial eruption (AE) is an orthodontic procedure aiming at assisting an impacted tooth to erupt and to align with adjacent teeth for functional and/or esthetic purposes. AE of multiple or poor prognosis impacted teeth is challenging and needs an interdisciplinary approach. The objective of this case report is to present the AE procedures and outcomes of two cases with complicated impacted dentition. The first patient had 3 high impacted maxillary anterior teeth of which self-eruption occurred after space in the dental arch was gained. The second patient had a tooth impacted in a poor prognosis position. The tooth was eventually brought into the arch after a series of attachment reposition and force direction design. All rescued teeth were well aligned with their adjacent teeth. Periodontal status was as healthy as their counterparts on the other side of the arch.

Page : 121-131

Title : HPMC Based Mucoadhesive for Delivery of Triamcinolone Acetonide:Mucoadhesion and Drug Release Properties, An In Vitro Study

Author(s) : Kanokporn Bhalang, Premrudee Srisuntorn, Pratanporn Arirachakaran

Keyword(s) : Muco-adhesive,Hydroxypropyl methylcellulose (HPMC),Triamcinolone acetonide,Muco-adhesion,Buccal patch.

Manuscript Type : Original Article (บทวิทยาการ)

Page : 121-131

Topical corticosteroid is the first-line drug for treating immune-mediated oral lesions, 0.1 % being the most effective concentration. However, conventional topical Triamcinolone acetonide (TA) applications are poorly retained on the oral mucosa. Hydroxypropyl methylcellulose (HPMC) polymer patches are used as buccal mucosa drug delivery systems, as they enhance a drug’s ability to adhere to the oral mucosa and reduce the frequency and amount of drug application. The objective of this study was to prepare a new HPMC-based buccal muco-adhesive polymer patch for the delivery of 0.1 % TA. The solubility, water absorption, muco-adhesion and in vitro drug release study using high-performance liquid chromatography (HPLC) were compared with a commercial product. The results revealed that the 3 % and 2 % HPMC patches had significantly lower dissolution rates, a favorable property, compared with that of the commercial product (p<0.05). The 3 % HPMC group demonstrated the highest dissolution time. Every concentration of the newly developed muco-adhesive polymer patches had higher water absorption than that of the commercial patches at 1 and 5 min. In addition, the 3 % and 2 % HPMC patches demonstrated significantly higher water absorption compared with the commercial patches at 10 and 30 min. There was no significant difference in muco-adhesion between the developed patches with commercial product. All HPMC groups did not show significantly higher drug release compared with the commercial product group at every time point. 3 % HPMC group had the highest drug release. The 3 % HPMC group had significantly higher drug release than 1 % HPMC at 2, 4 and 6 h. We demonstrated the potential of a buccal muco-adhesive polymer patch as an alternative treatment for oral ulcerations. The buccal mucosa patches had a higher dissolution time compared with the commercial product. The 3 % HPMC had lower dissolving and higher drug release at 2 to 10 h. The newly developed muco-adhesive polymer patches had improved properties pertaining to drug application. Further study is needed to improve some of the properties of the oral patches and to implement a clinical study.

Page : 132-143

Title : Evaluation of Voids in Class II Restorations Restored with Bulk-fill and Conventional Nanohybrid Resin Composite

Author(s) : Chalermpol Leevailoj, Saiisara Chaidarun

Keyword(s) : Bulk-fill resin composite,Class II cavity,Conventional resin composite,Increment,Void

Manuscript Type : Original Article (บทวิทยาการ)

Page : 132-143

Objectives: The aim of the study was to evaluate the influence of four resin composites on voids in small and large Class II cavities. Furthermore, the thickness of the first increment of the restorations was studied. Methods: Eighty artificial lower second premolars were divided into two preparation designs with 40 standardized Class II cavities in each, and then restored with four resin composites (three bulk-fill types: SonicFill 2, Filtek Bulk Fill (capsule), Filtek Bulk Fill (syringe) and a conventional nanohybrid resin composite: Premise). Restorations were sectioned for microscopic evaluation and a Kruskal-Wallis analysis was performed to evaluate the number of voids and percent void area. The thickness of the first increment was measured and analyzed. Results: There were significant differences in the number of voids and percent void area among the 4 groups in small cavities. SonicFill 2 and Filtek Bulk Fill (capsule) placed with the injection technique showing reduced voids. In contrast, no significant differences were detected among the 4 groups in large cavities. Most of the first increment thicknesses of the restorations in both cavity preparations were thicker than recommended. Conclusions: Voids were reduced when the injectable resin composites were applied in small Class II cavity preparations, and the best results were achieved using SonicFill 2.

Page : 153-164

Title : Adding Ferrous Sulphate to Hydrogen Peroxide Tooth Bleaching Gels Reduced the Required Bleaching Time

Author(s) : Thunnithie Thitichoatariyakunan, Sirivimol Srisawasdi

Keyword(s) : Bleaching,Chemical activation,Ferrous sulphate,Hydrogen peroxide,Tooth whitening

Manuscript Type : Original Article (บทวิทยาการ)

Page : 153-164

Objective To investigate the effect of ferrous sulphate (FeSO4) as a chemical activator to hydrogen peroxide tooth bleaching gels on color change and treatment time. Methods One hundred and twenty extracted human upper premolars, hue A or B, were selected. One enamel-dentin specimen was prepared from each tooth. The specimens were divided into twelve groups (n=10), based on bleaching product, FeSO4 and treatment time. Three in-office bleaching products were used in this study: Opalescence® BoostTM, PolaOffice® and ZOOM!® WhitespeedTM. Each product was used per its specific protocol: 1: untreated control (C), 2: FeSO4 added, using the product’s specified treatment time (Fe100 %), 3: FeSO4 added, using approximately 75 % of the specified time (Fe75 %), 4: FeSO4 added, using approximately 50 % of the specified time (Fe50 %). The color was measured before and immediately after bleaching, using a VITA Easyshade® V spectrophotometer based on the CIE-L*a*b* color system. Data between experimental groups of each product were analyzed using one-way ANOVA and Tukey’s or Tamhane’s test (p=0.05). Results Color parameter (ΔL, Δa, Δb and ΔE) evaluation indicated no differences between the C, Fe100 % and Fe75 % of each product. Compared with the C group, only Δb of the ZOOM!® WhitespeedTM Fe50 % group was significantly different (p=0.001). No differences were found between the Opalescence® BoostTM and PolaOffice® C and Fe50 % groups with each material. Conclusion Adding FeSO4 was effective in reducing the treatment time of Opalescence® BoostTM, PolaOffice® and ZOOM!® WhitespeedTM by at least 25 %.

Page : 165-172

Title : Age Estimation using Segmented Pulp/Tooth Area Ratio Method in Thai Population

Author(s) : Sakarat Nalampang, Anocha Poommouang, Anak Iamaroon, Sangsom Prapayasatok, Sukon Prasitwattanaseree

Keyword(s) : Age estimation,Maxillary central incisor,Periapical radiograph,Pulp/tooth area ratio

Manuscript Type : Original Article (บทวิทยาการ)

Page : 165-172

The aims of this study were to develop an age estimation equation in Thai population using segmented pulp/tooth area ratio (sPTR) and to test the reliability of that equation. The sample consisted of 400 digital periapical images of right maxillary central incisors derived from 163 men and 237 women aged between 10.03 and 81.61 years (mean=32.38 years). sPTR measurement modified from the Cameriere’s method was performed in the 400 samples. Subsequently, statistical analysis was performed in order to generate a regression model for age estimation. Then, another 103 samples were tested for the accuracy of the regression model. The difference between the chronological age and the estimated age was statistically calculated. The correlation coefficient was statistically significant, with r=-0.86 (p<0.05). The power regression model for the Thai sample yielded the following equation: Age=0.790×sPTR(-2.059). The coefficient of determination (R2) was 0.82. The mean difference value between the estimated and the chronological ages was -0.80. The mean absolute error (MAE) was 4.26 years. The standard error of prediction (SEP) was 5.70 years. In conclusion, the sPTR on the maxillary central incisor we firstly proposed in this study can be useful for age estimation in Thais.

Page : 173-180

Title : Comparison of Four Different Types of Dental Floss in Plaque and Gingival Inflammation Reduction

Author(s) : Supranee Benjasupattananan, Lily See

Keyword(s) : Clinical trial,Dental floss,Gingival inflammation,Plaque control

Manuscript Type : Original Article (บทวิทยาการ)

Page : 173-180

The aim of this study was to assess whether a reference manual toothbrush alone and in conjunction with variable width of floss would have different efficacy in plaque removal or result in different amounts of reduction of gingival inflammation. The randomized, controlled, double blind examiner, two-period crossover study examined floss efficacy in 34 healthy subjects following use of a standardized manual toothbrush alone and in combination with four floss products (Oral B® Essential floss, Oral B® Satin floss, Sparkle® expanded floss, Paldent® expanded floss). The gingival index score (Löe and Silness) and Rustogi Modified Navy plaque index score were examined. The results presented that mean gingival index score reductions (baseline minus endpoint) were as follows: 0.4628, 0.5005, 0.3818, and 0.3923 for the toothbrush in combination with Oral B® Essential floss, Oral B® Satin floss, Sparkle® expanded floss, and Paldent® expanded floss, respectively. Mean plaque reductions in floss contact areas were as follows: 0.3475, 0.3096, 0.3159, and 0.198 for toothbrush in combination with Oral B® Essential floss, Oral B® Satin floss, Sparkle® expanded floss, and Paldent® expanded floss, respectively. No statistically significant differences were found between any pairs of floss. All four floss treatments showed greater (p<0.05) plaque removal and reduction in gingival inflammation than toothbrush alone. In conclusion, all four floss products in combination with a manual toothbrush removed plaque significantly better than the toothbrush alone. Among floss types, there were no significant treatment differences.

Page : 181-196

Title : The Survey of Practice among Dentists on Dental Safety Goals and Guidelines (DSGG)

Author(s) : Pagaporn Pantuwadee Pisarnturakit, Pratanporn Arirachakaran, Chumphon Chamachot, Niphaphat Chitchutrakul, Phanthapha Khunthananithi, Phanthira Chuethonghua

Keyword(s) : Dental safety goals and guidelines,Dentist,Knowledge,Practice,Public hospital

Manuscript Type : Original Article (บทวิทยาการ)

Page : 181-196

This study aimed to survey and evaluate knowledge and practice of Dental Safety among Thai Dentists in public hospitals. Eight hundred and fifty-five dentists representing 855 public hospitals were asked to complete the online-survey questionnaire enclosed with details of the study along with the consent letter. The questionnaire regarding Dental Safety Goals and Guidelines (DSGG) classified into 5 categories- Safe Communication, Safe Dental Treatment, Safe Infection Control, Safe Record and Risk Management. Response options were graded on a 4-point-Likert scale ranging from 0 to 3. The non-respondents received a reminder email after the second week. The data was analyzed by descriptive statistics using Statistical Package for Social Science (SPSS, version 22.0). Two hundred and twenty-seven dentists returned the DSGG questionnaire. A response rate of 26.5 % was achieved. Participants were in hospitals in every region of Thailand. Approximately 57 % of them were DSGG-survey-participants in the last two years. The results indicating the highest DSGG compliance is Patient Medical History taking (score=2.90±0.22) and the lowest DSGG compliance is Respiratory Hygiene (score=1.58±1.13). The overall responses indicated that most dentists had good practice in regards to DSGG.

Page : 144-152

Title : Comparison of Frictional Resistance of Various Orthodontic Ligation Methods in Wet Conditions

Author(s) : Janya Apisariyakul, Wikanda Khemaleelakul, Nattawit Promma, Nutdanai Pongsusenee, Tonfon Damang, Norrawit Nuntasak, Panicha Thanasarnpoonpol, Prisadang Saksit, Pawarit Chullapak

Keyword(s) : Orthodontic ligation method,Static frictional resistance,Elastomeric ligature

Manuscript Type : Original Article (บทวิทยาการ)

Page : 144-152

The aim of this study was to compare the maximum static frictional resistance of the various orthodonticligation methods. The 0.019”x0.025” straight stainless steel main archwires were ligated on 0.022”x0.028” slot maxillary right central incisor standard stainless steel brackets. The samples were divided into six groups according to ligation methods (10 samples per group): stainless steel ligation (Group 1); and five elastomeric ligations which were conventional ligation (Group 2); one pair of wing ligation (Group 3); two pairs of wing ligation (Group 4); cross-wing ligation (Group 5); and figure of eight ligation (Group 6). Then, all samples were tested using a Universal Testing Machine. The main archwires were pulled vertically and the maximum static frictional resistance was calculated. In order to compare the mean maximum static frictional resistance among the groups, One-Way ANOVA and Dunnett’s T3 multiple comparison test were used. Most ligation methods had different maximum static frictional resistance (p<0.05). The least mean maximum static frictional resistance was in the stainless steel ligation group (37.12±15.15 g), and was not significantly different from that in the cross-wing elastomeric ligation group (44.10±7.50 g). The greatest static frictional resistance was in the figure of eight elastomeric ligation group (226.64±37.94 g).

Page : 1-12

Title : Thai Herbs: The Potential Application in Adjunctive Periodontal Therapy

Author(s) : Sireerat Sooampon, Widhunya Mathurasai, Waranyoo Phoolcharoen

Keyword(s) : Thai herbs,Periodontal disease,Anti-periodontal pathogen,Anti-inflammation

Manuscript Type : Review Article (บทความปริทัศน์)

Page : 1-12

Periodontal disease is one of the major health problem impacted the quality of human life and associated with systemic diseases. A number of antiplaque agents and antibiotics have been used as an adjunctive treatment for periodontal therapy. However, the use of these agents might increase bacterial resistance and unwanted side effects. Herbs are important sources of new drug development. Some herbs have been used for century in traditional medicine. This literature will provide the research information about Thai medicinal plants that have potential to be the candidates for development of anti-plaque and anti-periodontal agents in the future.

Page : 13-19

Title : The Usage of Oral Appliance for Maintaining Jaw Position in Hemimandibulectomy Patient: A Case Report

Author(s) : Wantanee Mutirangura, Uthai Uma, Seechompoo Norabhoompipat, Phanomporn Vanichanon

Keyword(s) : Oral appliance,Occlusal splint,Hemimandibulectomy,Mandibular deviation

Manuscript Type : Case Report

Page : 13-19

The maintenance of mandibular position is an important part of the treatment process in the hemimandibulectomy patient. It corrects the mandibular position into the normal and helps patient function the jaw. This case report presents the usage of an oral appliance modified from the upper occlusal splint, which the palatal and labial flanges were added for guidance in a 31-year-old female patient who was treated for myxoid chondrosarcoma by the right hemimandibulectomy. After the surgery, the patient had her mandible deviated 10 millimeters to the right in the habitual occlusion. By wearing the oral appliance at night time for 6 months, she could constantly bite in the intercuspal position without mandibular manipulation. The patient reported that her mastication was improved. In conclusion, the intraoral appliance modified from the occlusal splint is profitable in maintaining the mandibular position of the hemimandibulectomy patient.

Page : 20-27

Title : Longitudinal Tooth Fractures : Case study

Author(s) : Indra Wongyaofa, Nutta Chunasaksri

Keyword(s) : Longitudinal Tooth Fractures

Manuscript Type : Case Report

Page : 20-27

There are various patterns of longitudinal tooth fractures. Patients often present with pain or sensitivity.Radiographic evaluation cannot detect initial crack, it may difficult to locate the caused tooth. The location, direction and extension of cracks and fractures have an effect on the choice of treatment. Cracks and fractures are the pathways for bacterial penetration, which could lead to inflammation and disease of pulp tissue. In this report, clinical examinations, diagnosis and treatments of longitudinal tooth fracture are reviewed and discussed.

Page : 28-37

Title : Effect of Different Surface Treatment Methods on Shear Bond Strength of Orthodontic Metal Brackets to Four Provisional Restorative Materials

Author(s) : Mayurach Pipatphatsakorn, Marut Banrai, Ratchawan Tansalarak, Jutharat Chimruang

Keyword(s) : Bracket,Provisional restoration,Shear bond strength,Surface treatment

Manuscript Type : Original Article (บทวิทยาการ)

Page : 28-37

The aims of this study were to determine the effect of different surface treatment methods and provisional materials on the shear bond strength of orthodontic brackets. One hundred and sixty samples were randomly divided into 4 material groups (n=40); A: acrylic resin (Unifast™ Trad), B: bis-acryl (Protemp™ 4), C: polycarbonate crown (3M ESPE), D: denture teeth (Cosmo™ HXL). In groups A and B, 5×5×2 millimeter box-form cavities were prepared on cured resin blocks and these cavities were filled with provisional materials. After polymerization, the materials’ surfaces were polished and stored in distilled water for 7 days. In group C and group D, samples were embedded in a self-curing epoxy resin within polyvinyl chloride pipes in which the labial surfaces of C and D were above the self-curing epoxy resin and stored in distilled water for 7 days. Samples of each group were randomly divided into 4 subgroups of the following surface treatments (n=10); 1: Control, 2: 600-grit sandpaper, 3: Assure™ Plus, and 4: Sandblast. Lower incisors brackets (Gemini™, 3M) were attached with Transbond™ XT adhesive. All samples were stored in distilled water for 24 hours. A thermocycling procedure was conducted for 500 cycles between 5 °C and 55 °C. Samples were stored in distilled water for 24 hours. The shear bond strength was measured with a universal testing machine. The mode of failure was examined under a stereo microscope.
The results of the surface treatment groups showed that the mean shear bond strength of sandblasting groups was significantly higher than all other surface treatment groups of all materials, except for sandblasting on the bis-acryl group (B4) (p<0.05). Other surface treatment methods on all materials showed no statistically significantly difference except in the polycarbonate crown with Assure™ Plus (C3), which presented the lowest mean shear bond strength (p<0.05). The mean shear bond strengths of custom type materials (group A and B) were significantly higher than the prefabricated type material (group C and D) (p<0.05).
Both types of materials and surface treatment methods influenced the shear bond strength of the brackets bonded to the provisional materials. The sandblasting technique enhanced the shear bond strength effectively in all materials except for bis-acryl that originally expressed high shear bond strength even without surface treatment. The surface treatment that uses the sandblasting technique and using bis-acryl composite which exhibited higher shear bond strength to other materials and surface treatment may offer a good option in clinical practice.

Page : 38-47

Title : Relationship between Facial Alveolar Bone Thickness and Root Position of Maxillary Anterior Teeth Using Cone Beam Computed Tomography

Author(s) : Supranee Benjasupattananan, Papatpong Sirikururat

Keyword(s) : Facial alveolar bone thickness,Root position,Dental cone beam computed tomography,Anterior maxilla

Manuscript Type : Original Article (บทวิทยาการ)

Page : 38-47

This study purposed to assess the average of the facial alveolar bone thickness at the facial root surface of the maxillary anterior teeth, along with its relationship to the root position by using cone-beam computed tomography (CBCT) in a group of Thai population. Seventy CBCT scans (420 teeth) were randomly selected from the CBCT database at School of Dental Medicine, Rangsit University. The exclusion criteria were the subjects with extensive dental caries, fixed coronal restoration, severe root resorption, and destructive periodontal disease in maxillary anterior region. After recruitment, 406 teeth were used to measure facial alveolar bone thickness and sagittal root position (SRP). The data of the facial alveolar bone thickness was collected in cross-sectional dimensions. The measurements were performed at three reference points, which were 4 mm apical to CEJ (R1), midpoint between 4 mm to CEJ and mid-root (R2), and mid-root (R3). The results revealed that the facial alveolar bone thickness seemingly decreased apically in every type of tooth. The mean facial bone thickness of maxillary teeth was between 0.67±0.75 to 1.04±0.67 mm. The majority of examined teeth in this study exhibited Class I SRP (overall 92.87 %; central incisor 93.87 %, lateral incisor 89.85 %, and canine 95.56 %). Class II SRP was found to be 5.4 %, 5.22 % and 2.27 % in lateral incisor, central incisor and canine respectively. Class IV SRP was found only 1.73 % (lateral incisor 1.45 %, central incisor 1.50 % and canine 2.22 %). But Class III SRP did not present in this study. Simple correlation test showed no statistically significance between the facial alveolar bone thickness and root position. In conclusion, the anterior maxillary teeth have a high prevalence of thin facial alveolar bone wall. These findings may consider risking of facial alveolar bone dehiscence, fenestration or soft tissue recession after immediate implant placement. The majority of the root position is SRP class I which is favorable for the implant – alveolar bone engagement of immediate implant placement.

Page : 48-55

Title : Effect of Fiber Post and Stainless Steel Wire on the Flexural Strength of Repaired Denture Base Acrylic Resin

Author(s) : Kwanrutai Somsak, Issarawan Boonsiri, Jirachaya Kittipanyangam, Phattarasinee Phuntusuntorn, Janita Ngamnusonkit, Sakulthip Saichompoo, Ansipakorn Tungtawee, Suchanard Visetsiri, Chalisa Saisin

Keyword(s) : Denture base repair,Flexural strength,Fiber post,Stainless steel wire

Manuscript Type : Original Article (บทวิทยาการ)

Page : 48-55

The objective of this study is to evaluate the efficacy of fiber post and stainless steel wire on the flexural strength of repaired denture base acrylic resin. The forty-eight heat-polymerized acrylic specimens size 10x65x3.3 mm were divided into four groups; Group1: repaired with auto-polymerized acrylic resin (control), Group2: repaired with auto-polymerized acrylic resin reinforced with smooth surface fiber post, Group3: repaired with auto-polymerized acrylic resin reinforced with grooved surface fiber post, Group4: repaired with auto-polymerized acrylic resin reinforced with stainless steel wire. All groups were tested the flexural strength by using three-point bending machine. Statistical analyses were performed using one-way ANOVA. Values of p<0.05 were considered statistically significant. The results demonstrated that the flexural strength of the control group was not significantly different from the other groups, and the flexural strength of group 2-4 revealed no significant difference among themselves (p=0.067). In conclusion, the flexural strength of denture base acrylic resin repaired with auto-polymerized acrylic resin is not different from those repaired with auto-polymerized acrylic resin reinforced with fiber post or stainless steel wire. The fiber post and stainless steel wire are not effective in increasing the flexural strength of the repaired acrylic resin.
Page : 56-62

Title : The Efficacy of Surface Disinfectant Wipes After Exposure to Air by Un-capping the Container

Author(s) : Ampornaramveth Ruchanee, Unmanatakoon Supachai, Pechteewang Sawanya

Keyword(s) : Alcohol,Biguanides,Disinfectant wipes,Infection Control,Ionized Hydrogen peroxide

Manuscript Type : Original Article (บทวิทยาการ)

Page : 56-62

The objective of this study is to determine whether air exposure of different disinfectant wipes by un-capping the container alter the bactericidal efficacy. Three commercially available disinfectant wipes with different active ingredients consisting of CaviWipes™ (QAC & Isopropyl alcohol), SporeClear™ (QAC & Biguanides) and Optim 33TB (Ionized H2O2) were used in the experiment. Forty milliliters of stimulated saliva were collected from 15 healthy volunteers in the morning before performing daily oral hygiene care. The saliva was spread on sterilized leather surfaces and air dry. The surfaces were then used to test the effectiveness of disinfectant wipes those had been air exposed for 1, 4 and 18 hours compared with a group that tightly cap the container. The remaining CFU/mL of bacteria on the surfaces were calculated to compare log reduction. Data were statistically analyzed by Kruskal-wallis test and Mann-Whitney U test. A value of p<0.05 was considered significant. This study revealed that air exposure seems to marginally affect the antibacterial capability of disinfectant wipes with different active ingredients as determined by log reduction. Despite non-alcohol containing formula of SporeClear™, air exposure seems to worsen its activity, though no statistically significant difference was observed. Bactericidal activity of CaviWipes™ and Optim 33TB were quite stable regardless of prolonged air exposure or the order of sheet pulled out from the container. The outermost sheet of SporeClear™ was more affected by prolonged air exposure. To sum up, bactericidal efficacy of disinfectant wipes was minimally affected by duration of air exposure. Activity of SporeClearTM, a non-alcohol containing formula, was greater affected by time and order of sheet dependent according to its texture.

Page : 63-72

Title : Comparison of Microleakage between Glass-ionomer Sealant Versus Resin Sealants with and without Fluoride

Author(s) : Anoma Rattanacharoenthum, Porntip Phajongviriyatorn, Kanokwan Bannasan, Wanlee Natsungnoen, Siraprapa Meekhun, Siriwannapa Kawsamer, Nurihun Adam

Keyword(s) : Pit and fissure sealant,microleakage,Glass-ionomer

Manuscript Type : Original Article (บทวิทยาการ)

Page : 63-72

การศึกษาในห้องปฏิบัติการมีวัตถุประสงค์เพื่อเปรียบเทียบค่ามัธยฐานของค่าเฉลี่ยรอยซึมเล็กของสารผนึกหลุมและร่องฟัน 3 ชนิด โดยทำในฟันกรามน้อยบนจำนวน 102 ซี่ สุ่มแบ่งเป็น 3 กลุ่ม กลุ่มที่ 1 ผนึกหลุมและร่องฟันชนิดเรซินที่มีฟลูออไรด์ กลุ่มที่ 2 ผนึกหลุมและร่องฟันชนิดเรซินที่ไม่มีฟลูออไรด์ และกลุ่มที่ 3 ผนึกหลุมและร่องฟันด้วยกลาสส์ไอโอโนเมอร์ ตามวิธีการที่บริษัทกำหนด จากนั้นนำฟันไปแช่ในเครื่องควบคุมอุณหภูมิแบบร้อนเย็นเป็นจังหวะที่อุณหภูมิ 5 องศาเซลเซียสสลับกับ 55 องศาเซลเซียส จำนวน 500 รอบแล้วทาน้ำยาทาเล็บให้ทั่วฟัน โดยเว้นบริเวณที่ห่างจากขอบของสารผนึกหลุมและร่องฟันออกมา 1 มิลลิเมตร นำฟันไปแช่ในสารละลายเมทิลีนบลูความเข้มข้นร้อยละ 0.5 ที่อุณหภูมิห้องเป็นเวลา 24 ชั่วโมง ตัดฟันในแนวใกล้แก้มใกล้ลิ้นด้วยเครื่องตัดฟันยี่ห้อไอโซเมท และวัดรอยซึมเล็กด้วยกล้องจุลทรรศน์สเตอริโอกำลังขยาย 100 เท่า เมื่อเปรียบเทียบค่ามัธยฐานของค่าเฉลี่ยของรอยซึมเล็กทั้ง 3 กลุ่ม ด้วยสถิติทดสอบครัสคัล-วอลลิส ที่ระดับนัยสำคัญ 0.05 พบว่ามีความแตกต่างอย่างมีนัยสำคัญ (p<0.001) เมื่อพิจารณาเป็นคู่ของกลุ่มศึกษาด้วยสถิติทดสอบแมนวิทนีย์ ยู ที่ระดับนัยสำคัญ 0.0083 พบว่าค่ามัธยฐานของค่าเฉลี่ยรอยซึมเล็กของกลุ่มสารผนึกหลุมและร่องฟันชนิดกลาสส์ไอโอโนเมอร์กับชนิดเรซินที่มีฟลูออไรด์ และระหว่างกลุ่มสารผนึกหลุมและร่องฟันชนิดกลาสส์ไอโอโนเมอร์กับชนิดเรซินที่ไม่มีฟลูออไรด์ รวมทั้งระหว่างกลุ่มที่ผนึกหลุมและร่องฟันชนิดเรซินที่มีฟลูออไรด์กับชนิดเรซินที่ไม่มีฟลูออไรด์ มีความแตกต่างอย่างมีนัยสำคัญ (p<0.001) สรุปว่า สารผนึกหลุมและร่องฟันชนิดกลาสส์ไอโอโนเมอร์ เกิดรอยซึมเล็กมากกว่าสารผนึกหลุมและร่องฟันชนิดเรซินที่มีและไม่มีฟลูออไรด์

Page : 73-83

Title : The Relationship Between the Level of Sensory Hardness and Toughness Evaluation and Electromyography Parameters of Some Thai Foods

Author(s) : Phanomporn Vanichanon, Thanaporn Sowithayasakul, Weera Supronsinchai

Keyword(s) : Electromyography parameters,Foods,Hardness,Toughness,Visual analog scale

Manuscript Type : Original Article (บทวิทยาการ)

Page : 73-83

The purpose of this study is to investigate the relationship between the level of hardness or toughness evaluation and electromyography parameters of some Thai foods in 32 healthy young Thai adults who did not have masticatory problems. The subjects were given 5 Thai foods with different hardness and toughness to chew and afterward were tested for those levels by using visual analog scale (VAS) and electromyography. The result showed that the scores of each parameter obtained from VAS were significantly correlated with those obtained by electromyography (p<0.05, and r=0.224-0.384). A weak to moderate correlation between two test methods which may be due to the adaptability of masticatory muscles to the hardness and toughness of the food. Therefore, the evaluation of hardness and toughness level of food using a VAS questionnaire could partly reflect the functions of masticatory muscles.

Page : 84-91

Title : Mesially Impacted Mandibular Second Molars and Adjacent First Molars: A Study of Occlusal Inclination and Root Curvature Via Panoramic Radiographs

Author(s) : Udom Thongudomporn, Noppadol Chanpongsaeng, Soontra Panmekiate

Keyword(s) : Impaction,Mandibular second molars,Mandibular first molars,Occlusal inclination,Root curvature,Root development

Manuscript Type : Original Article (บทวิทยาการ)

Page : 84-91

There is very little available information on the root characteristics of mesially impacted mandibular second molars (7M). This study investigates occlusal inclination, root curvatures and calcification stage of unilateral 7M versus their normal counterparts (7N). Inclination and curvature of the mandibular first molars on the affected (6M) and control side (6N) were also assessed. Fifty-one digital panoramic radiographic images from study participants with unilateral 7M were examined with image J software. Occlusal inclination and degrees of root curvature at middle third and apical third level of mesial and distal root of 7M, 7N, 6M, 6N were measured and compared. Association between 7M occlusal inclination and degree of root curvature was tested. Calcification stage of 7M and 7N was evaluated by Demirjian Index. There were significant differences of occlusal inclination between 7M and 7N (P<0.01), and between 6M and 6N (P<0.01). In 7M, apical third of mesial root tended to curve mesially (P<0.01), whereas in 6M, apical third of both roots tended to curve distally (P<0.01) but the middle third of distal root tended to curve mesially (P<0.05). No association between the degree of root curvature and occlusal inclination was found for 7M. About one-quarter of 7M had delayed calcification compared to 7N. In conclusion, there were differences in root curvature between 7M and 7N, and 6M and 6N. 6M tended to be more upright than 6N. The degrees of root curvature and occlusal inclination of 7M were not related.