Avicenna Journal of Dental Research
Volume:3 Issue: 1, Jan 2011

Statement of the Problem: Periodontal disease is a periodontal tissue inflammation caused by gram-negative and other bacteria. The release of various cytokins and mediators, including nitric oxide, in the inflammation area usually has determental effects on the periodontium, potentiating the inflammatory process. In order to prevent this side effect, investigatiors have used anti-oxidants such as green tea or nitric oxide synthase inhibitors as a remedy. In this study the effect of green tea on salivary nitric oxide radical was investigated in patients with chronic periodontitis. Two groups of patients (n=10), sufferring from chronic periodontitis as control and case groups, were evaluated. The case group used green tea for a period of four weeks. The control group received no intervention. At the end of this period the salivary total nitrite concentration as an indicator of nitric oxide was measured by ELISA technique based on Griess reaction. The results were compared statistically by paired-t-test at P<0.05. Green tea reduced the salivary concentrations of nitric oxide significantly (P=0.000) in the case group in comparison with the control group which recieved no treatment. The results indicated that green tea may be considered a useful herb for treatment of chronic periodontitis.

Statement of the Problem: When root perforation occurs in the middle third of the root, considerable canal length that would normally be available for post placement must be filled by the repair material, which necessitates placement of a considerably shorter post, leading to poor retention. The aim of this study was to compare retention of titanium ParaPost luted with MTA and four different cements. One hundred recently extracted human sound mandibular premolars were selected and coronal portion of each tooth was removed. The roots were endodontically instrumented and assigned to 5 groups (n=20). In five groups, the specimens were obturated with gutta-percha/AH26 sealer and the post was cemented into the roots with one of the five luting agents: zinc phosphate Harvard (group ZP), glass-ionomer GC (group GI), resin cement Panavia F2.0 (group PF2), self-adhesive cement RelyX Unicem (group RU) and mineral trioxide aggregate White ProRoot (group MTA). In each specimen, a parallel-sided titanium ParaPost was seated to a depth of 10 mm in the post space prepared with the corresponding drill size. The debonding force (Newton) was measured using a universal testing machine and the failure mode was evaluated by a stereomicroscope. Statistical analysis was performed by ANOVA and Tukey test (α=0.05). The means and standard deviations of post retention in different groups were: ZP (311.3±41.0), GI (289.2±35.5), PF2 (285.0±29.5), RU (191.3±21.8) and MTA (185.0±24.4). One-way ANOVA showed significant differences in retention values between the groups (P=0.000). Tukey test showed that although there were no significant differences in the retention of posts luted with ZP, GI and PF2, they were significantly (P<0.05) higher than those luted with MTA and RU. The results of this study showed that retention of posts luted with mineral trioxide aggregate was lower in comparison with other common luting agents.

Statement of the Problem: In Iran and most countries temporomandibular disorders (TMDs) are part of the education curriculum of general dentistry. Most patients with these disorders are first referred to dentists. Therefore, awareness of general dentists’ knowledge in this field is very important. The aim of this study was to evaluate knowledge and beliefs of general dental practitioners regarding temporomandibular disorders in Sanandaj, Iran. A questionnaire, containing 20 questions about TMD (diagnosis and classification, treatment and prognosis, chronic pain and pain behavior) was given to 80 randomly selected general dental practitioners in Sanandaj as well as to 10 TMD experts (oral and maxillofacial surgeons and prosthodontists) in Hamadan. An overall response rate of 80% was achieved among the participants. The knowledge of general dental practitioners about TMD was similar to that of TMD experts in over half of the questions. Most of the agreements between the two groups were in the treatment domain and most disagreements were in chronic pain and pain behavior. According to the results, there is a need to develop and strengthen undergraduate dental course curriculum and continuous education programs in TMD and orofacial pain

Statement of the Problem: Malocclusion is a developmental problem, which results in social, psychological and functional problems for patients. The aim of this study was to evaluate the need for orthodontic treatment using the Index of Orthodontic Treatment Need (IOTN) among the 11?14-year-old students of Hamadan schools in 2010 and to find the correlation between Dental Health Component (DHC) and Aesthetic Component (AC). A cross-sectional descriptive study was conducted on 721 students who had not undergone orthodontic treatment. The subjects were randomly selected (361 males and 360 females). DHC was assessed by a calibrated examiner. AC was determined using 10 standard photographs shown to students. Data were analyzed using chi-squared test to determine differences in treatment needs between subgroups of the subjects. The two components were evaluated using Spearman's correlation and kappa tests. According to DHC, of 721 cases surveyed, 48.7% had mild need for treatment; 25.1% had moderate need; and 26.2% had definite need. The most frequently observed malocclusion was contact point displacement. According to AC, 88.1% of students had mild need for treatment; 7.8% had moderate need and 4.2% had definite need. Comparison of DHC and AC showed no agreement between them (kappa value=0.069). According to DHC of the IOTN, approximately one-third of the population had a definite need for orthodontic treatment, and contact point displacement was the most prevalent malocclusion. Although IOTN is a valid screening tool, patient's perception of orthodontic treatment does not always correlate with professional assessment. According to the result of this study, it is advisable not to use AC instead of DHC in epidemiological studies.

Statement of the Problems: Assessment of tooth caries rate, especially in high-risk portion of the society, is important in order to plan appropriate preventive protocols. The aim of the present study was to determine dental caries prevalence in 13?19-year-old Iranian students using two different caries indicators, including DMFT and SiC index. A total of 398 students, including 196 boys and 202 girls, participated in the present study; the subjects were selected through stratified cluster sampling method. For each student, decayed (D), missing (M), and filled teeth were detected and DMFT was calculated. After calculating DMFT, the participants were sorted according to their DMFT values. The mean DMFT of one-third of the participants with the highest DMFT values was considered SiC (Significant Caries) index. Independent t-test and one-way ANOVA were used to analysis data with SPSS 13. Mean DMFT values and SiC indexes of all the participants were 3.35±2.22 and 6.62±1.92, respectively. Mean DMFT values in relation to age were as follows: 13-16-year olds: 3.04±2.49; 16?19-year-olds: 3.66±2.95. The mean DMFT was 3.56±2.58 for boys and 3.15±2.63 for girls. According to the sex, SiC index was 6.11±1.98 for girls and 7.11±1.73 for boys; however, Sic index of 13?16- and 16?19-year-old students were 5.88±1.78 and 7.32±1.81, respectively. Age, fluoride therapy, tooth brushing, parents’ education and number of children may influence the prevalence of dental caries among 13?19-year-old students.

Congenital granular cell tumor (CGCT) is a unique benign tumor of soft tissue in newborns, which usually occurs on the anterior alveolar mucosa of the jaws. It is 8 to 10 times more prevalent in females than males. We present a case report of a 3-month-old female infant, who had a solitary mass on the anterior mandibular alveolar ridge. The lesion, which was histologically a congenital granular cell tumor, was removed completely by simple excision.

Statement of the Problem: Generally, the main source of fluoride intake is drinking water. Excessive consumption of bottled water as a substitute or in addition to the tap water supply may have implications for safe fluoride supplementation. In this study, fluoride contents in six commercial brands of bottled water were measured. Six different brands of bottled drinking water available in Hamadan, Iran, were selected. The fluoride concentration was determined in the laboratory by using a HACH spectrophotometer. The standard SPANDS method was used to determine fluoride ion concentration. The range of fluoride content of various bottled water products was 0.09?0.7 mg/L. In all the samples the fluoride contents on the labels were different from the measurements in the laboratory. The manufacturers’ labeling of fluoride concentrations in Iran may be inaccurate. When prescribing fluoride supplements, dentists should be aware of the fluoride content of bottled water products used by pediatric patients.