Nowadays advances in dental knowledge and technology continue at a faster pace. The significance of lifelong learning for dentists is indisputable. The purposes of this study were to investigate continuing dental education activities of Thai dentists
and to identify associating factors. A systematic random sample of 3,486 dentists in Thailand was surveyed by mailed questionnaires. Data were collected on their participation in continuing dental education activities during the calendar year 2000. There were 1,587 respondents (response rate = 50.6%); 1,390 of these were active practicing dentists. An index of continuing dental education was developed as a summary measure for dentist’s participation in continuing dental education activities.
Results showed that journal reading was the most frequently reported continuing dental education activity (97.2%). Based on a multiple regression analysis, four associating factors were identified: dentist’s age, being a specialist, the number of dentists in practice and being a private practitioner. Almost all dentists (95.5%) agreed on the necessity of continuing dental education. In conclusion, this study revealed a variety of continuing dental education activities among Thai dentists, as well as identified relevant factors. This information might be useful for future development of a system for continuing dental education in Thailand.

The objective of this study was to compare the performance and reliability of a laser fluorescence probe (DIAGNOdent®) with light and probe examination in tooth screening for occlusal caries in field conditions. The sample comprised 125 first molars of thirtythree 7-year-old children. Sealed and filled teeth were excluded from the study. Two dentists examined the teeth independently, twice with light and probe and twice with the laser probe. The scores for laser fluorescence ranged from 0-99 and the scores for light and probe were 1 intact, 2 initial white opaque caries, 3 enamel caries catching probe, and 4 dentin caries. Scores 1, 2 and 3 infer that the
tooth could be sealed, while fissures with score 4 should not be sealed. The intra- and inter-examiner reliabilities for the laser fluorescence probe measured by intraclass correlation coefficients ranged from 0.83-0.89 and for light and probe measured by kappa coefficients it ranged from 0.62-0.93. The mean laser probe score for teeth categorized by light and probe to be sealed and not to be sealed were 20.9 ± 25.5 and 72.8 ± 28.7 respectively. The average sensitivity and specificity values of the laser fluorescence probe with the cutoff points at 10, 20, 30, 40, and 50 when compared to light and probe ranged 75-100% and 52-89% respectively. The cutoff point that gave the best balance between sensitivity and specificity was 40 (sensitivity = 83%, specificity = 86%). The results indicate that the laser fluorescence probe has the potential to be an alternative method for screening teeth for occlusal caries under field conditions.

The purpose of this in-vitro study was to compare the efficacy of two tooth-whitening gel products: the dentist-prescribed type (OpalescenceTM) and the over-the-counter type (SparkleTM). The whitening efficacy was evaluated by measuring the value of L (black-white), *a (green-red) and *b (blue-yellow). Seventy-one recently-extracted premolars for orthodontic purposes were
intentionally darkened by applying LedermixTM paste into the pulp chambers for two weeks. Each tooth was sectioned longitudinally into two halves. The prepared surfaces were sealed with glass ionomer cement. One half of each tooth received OpalescenceTM (66 half-teeth), another half received SparkleTM (66 half-teeth) for two weeks of treatment. The other 10 halves received no
treatment and served as a control. After treatment, the specimens were stored in artificial saliva for observation of tooth color at 3-and 6-month intervals. Photographs were taken and the color changes of the tooth samples were compared between pretreatment of baseline/after 2 weeks of treatment, and at periods of 3 and 6 months’ post-treatment. After 2 weeks of treatment,
both gels whitened teeth significantly (p < .05). The ability to lighten the teeth of both gels was not significantly different (p > .05). There was no difference in color change in the two groups at 3 and 6 months’ post-treatment (p > .05). These findings suggested that under present experimental conditions both the over-the-counter type (SparkleTM) and the dentist-prescribed type (OpalescenceTM) are efficacious; this whitening effect was visible for a period of 6 months.

The aim of this study was to investigate the effect of frequency and type of 3 acidic foods and 2 preserved fruits on surface hardness of enamel over a period of time. Sixty-three human molar teeth (embedded in epoxy resin) were ground to obtain a flat enamel on occlusal surface. The specimens were then immersed cyclically to storage extracted solutions for seven rounds. Five storage extracted solutions were used in this study: Kangsom, Somtum, Yummamuong, preserved mango and preserved Madun whereas 0.1M citrate buffer solution at pH 5.0 and distilled water were used as comparator and control, respectively. The pH of storage extracted solutions was measured by pH meter (Orion model 520A, Boston, USA). Then surface hardness were measured by microhardness tester (Micromet II Buehler, Illinois, USA) at each interval time and observed by scanning electron microscope (SEM). The storage extracted solutions were titrated by 0.1 N sodium hydroxide solution (NaOH). Mean hardness values were analyzed by Repeated measure ANOVA and Dunnette’s T3 multiple comparison test. The mean pH ± standard deviation of storage extracted solution of Kangsom, Somtum, Yummamuong, preserved mango and preserved Madun were
4.6 ± 0.2, 4.6 ± 0.3, 3.9 ± 0.3, 2.9 ± 0.2 and 2.3 ± 0.2 respectively. The surface hardness of enamel (kg/mm2) exposed to various storage extracted solution (Kangsom 198.3 ± 3.9; Somtum 181.4 ± 5.1; citrate buffer solution 76.8 ± 5.9; Yummamuong 51.5 ± 3.9; preserved Madun 47.5 ± 5.7 and preserved mango 45.2 ± 9.6) decreased significantly (p < .05) compared with
distilled water (278.2 ± 4.6). In titratable acidity test, Yummamuong required the highest volume of NaOH. SEM exhibited the change of enamel surface of all specimens in all storage extracted solutions except distilled water. Therefore, the acidic foods and preserved fruits with lower pH than critical pH (pH 5.5) could effect on enamel surface in various degrees. Furthermore, the frequency of exposure has provided influences on erosive potential to enamel surface in the experimental condition.

Early childhood caries, which is caused by multifactorial etiologies, is the serious problem of oral health in children. The important factors are always related to their parents influenced by the basic of each family such as socioeconomic, education, occupation, child-rearing, knowledge, oral hygiene status, attitude and awareness in oral health. These factors also affect the caries incidence of their children. Thus caries prevention strategies require addressing parental roles.

Tooth wear is becoming more common in both children and adults. This is the final paper of a two-part series detailing clinical appearance, clinical problem and management of tooth wear. This article attempts to emphasize the increased concern over the need for prevention, early detection, control of tooth wear and proper restorative management.

Trigeminal neuralgia is a rare severe painful condition of face with sometimes unknown etiology. Mostly, in known cause cases, the trigeminal nerve root demyelination results from compression by an overlying artery and vein or tumor. The treatment is either medication with anticonvulsant drugs, e.g. carbamazepine, phenytoin, baclofen or neurosurgery. If the patient does not respond to medication or has severe side effects then surgery should be considered . Three cases of trigeminal neuralgia with various drugs use and their results were reported.

The purpose of this clinical study was to compare sealant retention between self-brushing alone and with additional prophylaxis. One hundred and twenty-three students were studied by split-mouth method. One hundred and eighty-eight pairs of first permanent molars of 7-8 year-old children were block-randomly-allocated; one tooth was cleaned only by self tooth-brushing, while additional professional prophylaxis was done on the opposite tooth. The sealant retention was evaluated at 6 and 12 months. The difference of sealant retention between the two cleaning method was analyzed by the Wilcoxon signed rank test at significant level .05. At 6 months, the self tooth-brushing group had retention rates of 90.9 % by tooth and 96.3 % by pit and fissure sites, less than that of the professional prophylaxis group of 95.1% and 98.1% respectively. However, there was not statistically significant difference. At 12 months, the self tooth-brushing group had retention rates of 79.7% by tooth and 92.1% by pit and fissure sites, while the retention rates of the professional prophylaxis group were 88.6% and 95.4% respectively. On the contrary, the difference was statistically significant (p = .020 and p = .035). In this study, the self tooth-brushing first permanent molar of 7-8 year-old children had retention rates less than professional prophylaxis-supplemented group by tooth or pit and fissure sites. The difference was statistically significant at 12 months.

The objective of this double blind randomized controlled trial was to evaluate the effectiveness of a recently developed local sealant (Prevocare) by comparing its retention on permanent molars with that of a standard imported sealant (ConciseTM). The study group comprised 145 pairs of contralateral lower first permanent molars of 6-9 year old children from Saraburi province. A matched pair experimental design was used in which Prevocare (Chulalongkorn University, Bangkok, Thailand) and ConciseTM (3M Dental Products, St. Paul, USA) were randomly allocated to one of the teeth within each pair. The sealed teeth were checked for retention and caries after 6 months. There were 138 children (276 teeth; 95.2%) remaining in the study. The mean retention rate at 6 months in the experimental group (Prevocare) was 98.6% with the 95% CI of 96.5 – 100%. The mean retention rate of the control group (ConciseTM) was 97.8% (95% CI 95.4,100%). The mean difference in retention rates between the two groups was 0.8% (95% CI –3.2, 4.6%). None of the sealant was completely loss and no carious lesions developed in the sealed teeth during the trial period. It was concluded that the experimental local sealant, Prevocare, was clinically equivalent to the standard imported sealant, ConciseTM, in terms of retention and caries prevention on first permanent molars at the follow up period of 6 months.

The objective of this study was to assess the protective effect and personal acceptance of closed-fitting mouth guard in prevention of dental erosion among swimming athletes. Twelve swimming athletes from an athletic school where trichloroisocyanuric acid (chlorine 90%) was used in the swimming pool were selected as samples. Each swimmer was provided with a vinyl closedfitting mouth guard to be used in every swimming occasion. Symptoms of tooth hypersensitivity, satisfaction and attitude towards the device were measured using a questionnaire developed by researchets before and during wearing the mouthguard (at 2, 4 and 6 weeks) Acidity of swimming pool was recorded using pH paper every day when the samples practiced in the pool. The study revealed that after using mouth guard, mean tooth hypersensitivity score was decreased with statistically difference from the beginning (p < .001). Assessment of satisfactory and attitude score indicated high scale with no statistically difference from the beginning. The average acidity of the pool was between 3-4. The result showed that closed-fitting mouth guard is an effective and satisfactory personal protection against dental erosion for swimming athletes who swam in low pH swimming pool.

The aim of this study was to evaluate the effectiveness of Atelo-collagen sponge in ridge preservation after tooth extraction. Ten patients requiring extractions of 2 molar teeth participated in the study (split-mouth design). Preoperative study models were taken for the preparation of 3 mm in diameter metal ball holing stents. Following extraction of the teeth, experimental sites were covered with Atelocollagen sponge and stay sutured with black silk; control sites were left to heal spontaneously. Patients were scheduled for 4 periodic appointments after extraction; 1 week, 1 month, 4 months and 6 months. Study models and periapical films were taken at each appointment. The buccolingual width of the alveolar ridge at cervical third and apical third were measured from the study models while the height of the alveolar ridge was measured from the films. Data were evaluated using Mann-Whitney U test, Friedman test, and Wilcoxon signed ranks test. The results revealed statistically significant difference at 4 and 6 months that control sockets had smaller size than study sockets. The radiographic pictures showed more opacity at the area of socket in study group at the beginning of 4-month-follow up. A white line was more remarkable at the top of the lesion and the outline of the socket could not be traced. This study indicated that Atelocollagen sponge is valuable in preserving alveolar bone in extraction sockets.

The quantities and qualities of proteins in extracts from eleven glove brands of four glove types, powdered latex examination gloves, powder-free latex examination gloves, powdered latex surgical gloves, and synthetic (vinyl) gloves, were determined and compared. All glove extracts were measured for protein concentrations by Bradford’s assay and molecular weights of proteins were identified by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The results showed various quantities and qualities of proteins in tested gloves. The powdered latex examination gloves had the highest median of protein concentration (128.84 μg/g), followed by powdered latex surgical gloves(31.48 μg/g), powder-free latex examination gloves (9.99 μg/g), and synthetic (vinyl) gloves (2.64 μg/g) respectively. Significant differences of protein concentration were found among the glove types. (p < .05) The qualitative study identified proteins at molecular weights of 11, 12, 26, 31, and 44 kD in latex gloves. The powdered latex examination gloves contained proteins at molecular weights of 11, 26, 31, and 44 kD, while powder-free latex examination gloves and powdered latex surgical gloves contained proteins at molecular weights of 11 and 12 kD. The most common protein had a molecular weight of 11 kD. All latex gloves in this study had proteins, which may induce allergic reactions. Therefore, individuals who are definitively diagnosed as latex protein hypersensitive should avoid using latex gloves.

In Thailand, porcelain fused to metal restoration is gaining high popularity. Ni-Cr alloy is most widely used due to its
superior mechanical properties and low cost. All alloys in dentistry have to be imported and there is no quality control. The purpose of this study was to evaluate mechanical properties of commercial Ni-Cr alloy used for ceramo-metal restoration based upon the ISO 9693 “Dental ceramic fused to metal restorative materials”. Eight brands of Ni-Cr alloy were selected and tested. To avoid any commercial conflict, all alloys were blindly named with letters A to H. The alloys were tested for surface hardness and tensile properties such as percentage elongation, 0.2% proof stress and ultimate tensile strength. All alloys showed large variation in properties. Two alloys (A and E) did not pass the ISO requirement for percentage elongation. Four alloys (A, B, C and D) showed higher surface hardness than the company’s indicated values. The result suggested that quality control should be conducted and a domestic testing house should be established to ensure quality control.

This research project aimed to develop a light-activated pit and fissure sealant (Prevocare) for domestic uses. The first step was to compare physical properties of this material with an imported product (Concise, 3M Dental Products, USA). Prevocare was prepared from a mixture of Bis-GMA and TEGDMA monomers, an initiator system, and opaquer (titanium dioxide). The properties tested were depth of cure and uncured film thickness according to ISO 6874:1988, water sorption and solubility according to ISO 4049:2000, degree of conversion using FTIR and Vickers hardness. The difference between Prevocare and Concise was analyzed with t-test at a 0.05 significance level. There was no significant difference between uncured film thickness and degree of conversion of Prevocare and Concise. Prevocare showed significantly higher water sorption, water solubility, depth of cure and hardness than Concise. Properties tested following ISO 6874:1988 and ISO 4049:2000 for Prevocare and Concise were within the ISO requirements.

The purpose of this study was to determine biological properties, cytotoxicity and tissue biocompatibility of Prevocare in comparison with an imported product (Concise, 3M Dental Products, USA). Cytotoxicity was assessed in human epithelial cell line HaCat with MTT assay. The assay was carried out directly (cells in contact with sealant specimen), and indirectly (culture broth in contact with specimen 24 hours). The difference between groups was analyzed with t-test at a significant level of .05. Percentages of cell viability (direct contact) were 96.74 ± 1.78 and 94.14 ± 3.67 for Prevocare and Concise, respectively. Percentages
of cell viability (indirect contact) were 99.25 ± 1.48 and 98.39 ± 13.48 for Prevocare and Concise, respectively. Both sealants were not cytotoxic to HaCat cell culture. Biocompatibility was evaluated by embedding the specimens in dorsal area of Wista rat. Tissue response was examined histologically at 1 month and 3 months. Tissue response to both sealants was similar, e.g., fibrous capsule with infiltration of mononuclear cells was found. Biological properties of Prevocare were similar to the imported product. Both materials were not cytotoxic and showed tissue compatibility. Prevocare is safe to be used for clinical
evaluation.

Phosphoric acid is used routinely for bonding sealant to enamel. This research project aimed to develop a phosphoric acid gel “Prevocare Etchant” and to compare shear bond strength between sealant and enamel treated with Prevocare Etchant withan imported phosphoric acid gel (3M Etchant, 3M Dental Products, USA). Enamel surface of extracted human molars was ground flat, conditioned with either Prevocare Etchant or 3M Etchant for 15 seconds, rinsed with water, and blown dry. Cylindrical specimen was prepared from either Prevocare Sealant or Concise on etched enamel surface (n=10). The specimens were kept 24 hours before being fractured under shear load using a Universal testing machine. Shear bond strengths of both groups were calculated and compared using t-test at a 0.05 significant level. Shear bond strengths of enamel treated with Prevocare Etchant / Prevocare Sealant and 3M Etchant / Concise were 14.5 ± 3.3 MPa and 13.6 ± 2.7 MPa, respectively. Both values were not significantly different (t-test, p > .05). Scanning electron micrographs of acid-conditioned enamel in both groups revealed honeycomb appearance which is an effective pattern for bonding. Prevocare Etchant when used with Prevocare Sealant provides bonding performance comparable to an imported product.

This study aimed to investigate the bone healing capacity of using chitosan-gelatin sponge as bone substitute material in rabbit calvarial bone defects and to compare with autogenous bone grafting. Six New Zealand white rabbits were included in the study. Two identical 8 mm diameter cranial bone defects were prepared in each rabbit and grafting was done with autogenous bone from defect preparation and chitosan-gelatin sponge. After 12 weeks, bone defects of the two groups were evaluated qualitatively and quantitatively by means of radiography (step-wedge calibration, imaging densitometry) and histology (histomorphometry, digital imaging analysis). Results showed that chitosan-gelatin sponge promoted bone healing in part by its osteoconductive property. Up to 40-45% of areas of new bone formation were found in the specimens from chitosan-gelatin sponge group. There was statistical difference in both radiographic optical density and histomorphometric percentage bone area when comparing between the two groups (p < .05). To conclude, the use of only chitosan-gelatin sponge could not replace autogenous bone graft with regard to bone healing capacity. However, further studies of other modifications of chitosan-gelatin sponge grafting are indicated.

Several studies have shown that hyaluronan in gingival crevicular fluid (GCF) is a potential marker for gingival inflammation. Whole saliva is an alternative specimen to determine hyaluronan concentration. However, only a few studies have been done on the correlation between hyaluronan profiles in whole saliva and the inflammation of periodontal tissue. The present study was undertaken to determine the differences in the hyaluronan profiles of saliva collected from volunteers with 5 different stages of inflammatory periodontal tissue diagnosed by using the Periodontal Screening and Recording (PSR) index. Whole saliva was collected from 133 volunteers. By using Enzyme-Linked Immunosorbent Assay, the concentration of hyaluronan in
each sample was determined. Hyaluronan levels from each group were statistically compared using non-parametric analysis. We found that the concentrations of hyaluronan in all saliva samples were in the range of 4.5-14,037 ng/ml. The distribution of hyaluronan was not a normal probability plot; therefore, data in each PSR group was presented in median instead of mean values. The median values of hyaluronan in saliva among 5 PSR groups were not significantly different (p = .93, Kruskal-Wallis Test). While hyaluronan in GCF is a potential marker for the inflammatory process, hyaluronan in whole saliva from this crosssectional study could not be used as an indicator for inflammation of the periodontium.

The objective of this study was to compare the oral health status of asthmatic children with different levels of disease severity with their healthy peers. One hundred asthmatic children, aged 3 to 12 years(7.3 ± 2.6), and healthy controls whose ages, sexes and socioeconomic status were comparable were studies. All children were examined and evaluated for dental caries status and gingival condition. The Mann-Whitney U test and Kruskal-Wallis test were used for statistical analysis. Asthmatic children had significantly higher caries scores in their permanent teeth than those of healthy children’s (p = .000) while there were no difference in primary teeth. Caries scores in patients with different levels of asthmatic status were not different. In
addition, asthmatic children had significantly higher gingival index scores than healthy children (p = .000) but no difference was found in patients with different levels of asthmatic status. It was concluded that asthmatic children have higher caries in their permanent teeth and higher gingivitis than healthy children.

Glandular odontogenic cyst is a rare developmental cyst of the jaw, recognized as a distinct entity in the latest WHO’s histological typing of odontogenic tumors. We report here one additional case of glandular odontogenic cyst, presenting at the anterior part of mandible of an 80-year-old man. Clinically, the patient showed no observable intraoral swelling and had no other related symptom. Radiographically, the lesion was a well-defined unilocular radiolucency, extending from the area of lower left canine (#33) to lower right central incisor (#41). Histopathologically, the lesion revealed a cystic wall with the lining epithelium exhibiting characteristic features of glandular odontogenic cyst. The total enucleation was performed with normal healing of surgical wound.

The Universal Coverage policy introduces major changes in Thailand’s dental profession. The aim of this research was to assess the impact of Universal Coverage (UC) Program on dental practice profiles among Thai active practicing dentists. A systematic random sample of 3,876 dentists in Thailand was surveyed by mailed questionnaires. Data were collected on their participation in the UC Program and on practice profiles. After two rounds of mailing, 1,712 dentists returned questionnaires (response rate = 49.7%). The number of active practicing dentists was 1,260. The results showed that UC dentists accounted for 55.8% of dental workforce in 2002, mostly in district hospitals. Several significant differences in practice profiles were identified between UC and non-UC dentists. UC dentists were more likely to treat larger number of patients, deliver more extractions and restorations, and deliver more sealants, as compared to non – UC dentists. UC dentists also reported a significantly higher level of job stress than non – UC dentists (62.7% vs. 21.0%, p < .001). In conclusion, this study elucidates the impact of UC Program on Thai dentists’ practice profiles,
which were not in accord with the oral health promotion paradigm.

This study aimed to compare the safety and the efficiency of the soft, slim-bristled toothbrush and the round-ended toothbrush in plaque removal. Additionally, the efficiency of these 2 types of toothbrushes in preventing gingivitis was also compared. Ninety eight volunteers were divided into clusters based on their mean plaque and gingival indices. Volunteers in each cluster were randomly assigned to use the soft, slim-bristled (test group) or the round-ended toothbrushes (control group). At the preparatory stage, they received scaling, root planing and polishing and were instructed to brush with the modified Bass technique. Two days before the experimental period started, volunteers received re-scaling and polishing before refraining from any oral hygiene practice. At the baseline examination, the parameters including plaque index, gingival index, bleeding index and gingival traumatic index were measured. Volunteers were allowed to brush using the assigned toothbrushes and toothpaste twice daily without other oral hygiene aids. Plaque and gingival traumatic indices were recorded immediately after the subjects finished their brushing. GI and PI2 were assessed at the end of the 2nd and 4th week while bleeding index and gingival traumatic index were assessed at the end of 4 th week. The results showed that both types of toothbrushes could remove plaque and cause gingival trauma without significant differences between them. However, the signs of gingivitis gradually progressed in both groups due to the presence of residual plaque.

The purposes of this study were to determine the parents’ knowledge of fluoride, the fluoride uses in young children, and the relationship between the age, educational level and income of parents and their knowledge of fluoride. A total of 282 parents completed a self-administered questionnaire enquiring about their knowledge of fluoride. Parents were mother or father of the 1- to 6-year-old children who attending pediatric dental clinic, Faculty of Dentistry, Mahidol University, Bangkok, Thailand. The average age of parents was 37.45+6.11 years. Most of parents received Bachelor’s degree (48.6%). The average score of their fluoride knowledge was 52.29+19.93 percent. Although most of them (97.9%) knew that fluoride could prevent caries, only 55% knew that using improper amount of fluoride might cause dental fluorosis. Only 39.0% of parents knew that children under 6 years old should use only a small pea-sized amount of paste, and 13.5% knew the recommended level of fluoride in toothpaste for children. Thirty-eight percent of parents knew that toothpaste swallowing was dangerous. Children’s sources of fluoride were fluoride toothpaste (95.7%), fluoride tablet (36.9%) and fluoride mouthrinse (7.1%). Fifty-three percent of parents reported that their children applied fluoride toothpaste by themselves and only 30.1% of parents reported used a small pea-sized amount of paste. There was a significant association between their educational level and knowledge of fluoride (p = .001). There was no significant association between the age or household income and the parents’ knowledge of fluoride. It was concluded that knowledge of fluoride among Thai parents in this study was moderate. Dental health care professional should emphasize parents more on the important of appropriate use of fluoride, especially on the proper amount of fluoride toothpaste used, the adverse effect of fluoride toothpaste swallowing and excessive fluoride exposure in young children, the instruction if children intake excessive fluoride, and the proper fluoride concentration in children’s toothpaste.

Surgical removal of cancer in the soft palate often leaves a defect that causes an oronasal communication. As a result,daily life of the patient is inevitably affected especially in swallowing and speech intelligibility. Therefore, the construction ofspeech-aid prosthesis should be initiated as early as possible. Existing complete denture that patient used prior to surgery canbe modified into speech-aid prosthesis by incorporating the wire-extension speech bulb. This article presents in detail a step-bystepprocedure, including the method of molding speech bulb with the intention for practical application. 

Impurities in mercury from different purification methods may deteriorate physical properties of dental amalgam. Faculty of Dentistry, Mahidol University (Thailand) purified contaminated mercury from by-product of natural gas refining process for dental application by three different methods. The methods were detergent (Teepol®) washing, detergent washing followed by nitric acid cleaning, and detergent washing plus triple distillation. Therefore, the objective of this study was to evaluate physical properties of dental amalgam mixed with the purified mercury, compared with commercial mercury. Three different types of purified mercury and
commercial mercury (Shofu spherical D capsule®, Shofu, Japan) were mixed with commercial dental amalgam alloy (Shofu spherical D capsule®, Shofu, Japan) to prepare dental amalgam specimens. The specimens were tested for compressive strength, dimensional change, and creep following ISO 1559 “alloys for dental amalgam”. The results revealed that the mercury purified from various methods in this study did not affect the properties of dental amalgam, and the properties were not different from the control (p >.05). All
of dental amalgam specimens in this study passed the ISO 1559 requirements.

The aim of this study was to evaluate the association of head form and dental arch form in pediatric subjects. Eighty eight children (47 males and 41 females) with no premature loss and no proximal caries which could affect arch length participated in this study. Maximum cranial width and maximum cranial length were measured using the Spreading caliper round point No. 106 of GMP. Cephalic index was calculated. The results showed that the majority of head form were brachycephaly (84.21 ± 4.75). Dental arch form was classified by a measurement of transitional angle from study models. Eighty nine percent of subjects had ovoid arch form, the rest (11%) were square. No tapered arch form was found in this study. Data were statistically analyzed using Spearman Rank Order Correlation at significant level .05. There was no statistically significant association between head forms and dental arch forms. (p > .05)

This in vitro study compared the efficacy of smear layer removal by Largal Ultra‚ and 5 formulated EDTA solutions; they were 15% and 17% EDTA mixed with cetyltrimethyl ammonium bromide (formula 1 and 2, respectively), 15% and 17% EDTA mixed with ethylene diamine (ED, formula 3 and 4, respectively), and four parts of 17% EDTA mixed with three parts of 5% ED (formula 5). Twenty orthodontically extracted human teeth were splitted in bucco-lingual direction into two equal parts after canal instrumentation. The canal wall was irrigated with each experimental solution for 1 or 5 min (n = 3 each), and then irrigated with 2.5% NaOCl for 1 min. Teeth in control group were only irrigated with 2.5 % NaOCl for 1 min. The smear layer removal and the amount of opened dentinal tubules were evaluated under SEM. The result revealed less smear layer in groups treated with formula 1, 2, 3 and 4 than those treated with formula 5 and Largal Ultra. At 1 min irrigation, the teeth treated with formula 1, 3 and 4 had higher amount of opened dentinal tubules than those treated with formula 2,5 and Largal Ultra (p < .05). At 5 min irrigation, the amount of opened dentinal tubules in teeth treated with each of the five formulated EDTA solutions did not differ
from each other, but they were higher than Largal Ultra (p < .05).

The purpose of this study was to identify associated risk factors of early childhood caries (ECC) in a sample of Thai children 6-30 months of age. Samples were children who came for vaccination at well baby clinics in 296 MOPH hospitals from 24 provinces (12 regions: 2 provinces per region) during August - September, 2003. Data were collected from children’s oral examination and caregivers interviews, using a 30-question form developed by the research team. Analyses were performed by Chi–square test, analysis of variance (ANOVA) and forward stepwise logistic regression. A total of 3,790 complete interviews and dental examination cases (73.1 %) were analyzed. The results revealed that the majority of the caregivers were mothers (58.9%) residing in rural area (70%) with an income of < 10,000 bahts per month (80.1 %) and with an education at the primary school level (57.9 %). The prevalence of ECC were 1.4 % in 6-12 month-old children, 16.6 % in 13-24 month-old children and 45.4 % in 25-30 month-old children. Associated risk factors of children’s caries experience included age (OR= 19.3, 95% CI, 7.9- 47.2, p = .000), oral hygiene (OR= 9.2, 95% CI, 6.9-12.1, p = .000), prolonged rice keeping in the mouth (OR = 1.8, 95% CI, 1.4-2.6, p = .000), frequent consumption of high-risk snacks (OR = 1.5, 95%CI, 1.2-1.9, p = .001), sleeping with bottle (OR = 1.4, 95%CI, 1.1-1.8, p = .013), and no-vegetable consumption behavior (OR=0.683, 95%CI, 0.5-0.9, p = .003).

Radiotherapy for head and neck cancers has long been known to complicate the dental and oral health of patients. The objective of the present study was to investigate oral health status of patients with head and neck cancers in northern Thai patients who were undergoing the radiotherapy. Seventy-six patients with head and neck cancers undergoing the radiotherapy with or without chemotherapy were recruited for oral examinations including DMFT, periodontal, mucosal, and oral hygiene conditions. In addition, candida infection, salivary flow rate, and maximum jaw opening were evaluated. The results showed that
the mean DMFT and mean plaque index were 3.0 and 1.38, respectively. Of all patients, 48.7% had mucositis, 23.7% had xerostomia, 32.9% had restricted mouth opening and 36.8% had oral candidiasis. C. albicans was the most common species isolated. Concerning dental treatment required, 45.6 % of the patients needed fillings at least one or more teeth, 38.2% needed extraction of at least one or more teeth, and 51.5% needed periodontal treatment. In conclusion, these findings indicate that dental and periodontal prophylaxis prior to radiotherapy in this group of patients was inadequate.

The aim of mandibular reconstruction, after trauma or ablative tumor surgery, is to restore masticatory function, deglutition, phonation, and facial esthetics. Nowadays, free vascularized bone grafts with microvascular reconstructive surgery have become the preferred method for mandibular reconstruction.
This is the first case report of the Faculty of Dentistry, Chulalongkorn University that used the osteomyocutaneous fibular free flap with the microvascular surgery reconstruction for the large intraoral soft tissue and mandibular bone defects after resection of recurrent ameloblastoma in which a reconstruction with non-vascularized bone graft was not possible. At one-year follow up, the patient was free of disease with normal facial contour, demonstrated normal mandibular function and proper oral mucosa for denture substitution.

Radiotherapy for head and neck cancers has long been known to complicate the dental and oral health of patients. The objective of the present study was to investigate oral health status of patients with head and neck cancers in northern Thai patients who were undergoing the radiotherapy. Seventy-six patients with head and neck cancers undergoing the radiotherapy with or without chemotherapy were recruited for oral examinations including DMFT, periodontal, mucosal, and oral hygiene conditions. In addition, candida infection, salivary flow rate, and maximum jaw opening were evaluated. The results showed that
the mean DMFT and mean plaque index were 3.0 and 1.38, respectively. Of all patients, 48.7% had mucositis, 23.7% had xerostomia, 32.9% had restricted mouth opening and 36.8% had oral candidiasis. C. albicans was the most common species isolated. Concerning dental treatment required, 45.6 % of the patients needed fillings at least one or more teeth, 38.2% needed extraction of at least one or more teeth, and 51.5% needed periodontal treatment. In conclusion, these findings indicate that dental and periodontal prophylaxis prior to radiotherapy in this group of patients was inadequate.

The Universal Coverage policy introduces major changes in Thailand’s dental profession. The aim of this research was to assess the impact of Universal Coverage (UC) Program on dental practice profiles among Thai active practicing dentists. A systematic random sample of 3,876 dentists in Thailand was surveyed by mailed questionnaires. Data were collected on their participation in the UC Program and on practice profiles. After two rounds of mailing, 1,712 dentists returned questionnaires (response rate = 49.7%). The number of active practicing dentists was 1,260. The results showed that UC dentists accounted for 55.8% of dental workforce in 2002, mostly in district hospitals. Several significant differences in practice profiles were identified between UC and non-UC dentists. UC dentists were more likely to treat larger number of patients, deliver more extractions and restorations, and deliver more sealants, as compared to non – UC dentists. UC dentists also reported a significantly higher level of job stress than non – UC dentists (62.7% vs. 21.0%, p < .001). In conclusion, this study elucidates the impact of UC Program on Thai dentists’ practice profiles,
which were not in accord with the oral health promotion paradigm.

The objective of this study was to compare the efficiency of the dental diagnostic and procedural coding systems between general public health database (ICD-10/ICD-9-CM), the dental public health database (CDT), and ICD-10-TM. The study was performed in 3 aspects, i.e. coverage, discrimination ability, and accuracy. For the coverage, the manuals were compared to the dental procedural checklists and patients’ records from the Dental Department, Thammasat University Hospital. For the discrimination ability, the manuals were compared to the checklists, and the unclear codes were identified and analyzed. For accuracy, coders who want to ICD workshops performed the 40 diagnostic and procedural code tests. The coverage of the procedural codes of ICD-9-CM, CDT, and ICD-10-TM was 72.7%, 92.1%, and 92.6% respectively, while the percentage of unclear codes was 9.6, 4.4, and 3.2 respectively. The accuracy of diagnostic code in ICD-10 was 69.3%, and ICD-10-TM was 78.4%. The accuracy of procedural code in ICD-9-CM was 37.2%, CDT was 40.5%, and ICD-10-TM is 41.3%. It can be concluded that ICD- 10-TM provides more accuracy than ICD-10 for diagnosis, with more details. For procedural coding system, ICD-10-TM was
comparable to the dental public health database CDT, in terms of its properties. However, its coverage and discrimination ability are clearly better than ICD-9-CM.

The purpose of this descriptive study was to identify village people’s explanatory model regarding early childhood caries by Klienman’s explanatory model conceptual framework. Different qualitative data collection techniques were used including records, a participant observation, informal interviews, in-depth interviews and pile sorting that collected from 36 key informants, and oral examination of 38 children. The results show that some of the village people’s explanatory pattern agrees with professional knowledge, while some do not, due to different reality backgrounds. The village people’s conceptions are based upon accepted natural phenomena. Most oral health practices aim for emergent pain relief. The understanding from the present study should help health care providers administer appropriate dental interventions that are culturally suitable to popular thoughts, beliefs, and lifestyles to improve public child oral health goals.

The purpose of this study was to compare the antibacterial effectiveness of 2.5 % Sodium hypochlorite and 2 % Chlorhexidine on Enterococcus faecalis (ATCC 29212). Sixty-five extracted human single-rooted teeth were used. These teeth were divided into 4 experimental groups (n=15), a positive control group (n=4) and a negative control group (n=1). The crown of each tooth was sectioned to obtain the root of 12 mm long and sterilized. The 64 sectioned roots (the experimental and the positive control group) were infected with Enterococcus faecalis incubating in Todd-Hewitt broth for 2 weeks. Canals were instrumented using
stepback technique until master apical file was size 40. Group 1, canals were irrigated with 2.5 % NaOCl 20 ml with smear layer removed using 17 % EDTA 10 ml and 5.25 % NaOCl 10 ml. Group 2, canals were irrigated using 2.5 % NaOCl 20 ml and 0.9 % normal saline 20 ml. Group 3, canals were irrigated with 2 % Chlorhexidine 20 ml and 0.9 % normal saline 20 ml. Group 4, canals were irrigated with 2.5 % NaOCl 10 ml and 2 % Chlorhexidine 10 ml and 0.9 % normal saline 20 ml. In the positive control group, canals were irrigated with 0.9 % normal saline 40 ml. In the negative control group, canal was not infected, no instrumentation and no irrigation. The dentin chips from a sterilized round bur size ISO 012 were cultured for 24 hr to determine the presence of the colonies of Enterococcus faecalis. The colony was confirmed using the biochemistry method. The results of Chi-square test indicated no statistically significant differences (p >.05) between the experimental groups. However, the irrigating solutions from all experimental groups can eradicate microorganisms better than a positive control group (p <.05). Smear layer has no statistical
significant difference (p >.05) in eradicating microorganisms whether it was removed or intact.