مجله تحقیق در علوم دندانپزشکی
سال نهم شماره 2 (پیاپی 32، تابستان 1391)

Background and Aime: This research was launched in 2011 considering the bacterial contamination of surgery tools and unknown consequences due to this and lack of interventions to find out the answer for the question “How we can control bacterial contamination? The study was performed action research method on single packed and surgery sets sterilized in Islamic Azad University on random basis.First, the washing method was changed using eight samples of surgery tools but there was no significant difference contamination of tools with debri or without debri after sterilization (half of each group were contaminated). then we reduced the autoclave loading. During each level we prepared some samples from hemostate pans and elevator periosets after completion of sterilization process and the cultures were transferred to microbiology faculty of Shahid Beheshti Medical university within one hour. In the levels that bacterial contamination was zero percent after microbe culture if the same finding was proved for three times, we would have been able to control contamination. Resulte: The study indicated that changing quality of washing may not be influential factor in contamination control but reducing the sets and single packs inside the 300 liter autoclave from 82 sets to 65 sets and 38 single packs and in 150 liter to 48 sets and 37 single packs, we can control contamination. It seems by said loading in the autoclave can control the bacterial contamination but since this is the first research experience, more research should be done.

Pain and dry socket are the most common problems following the removal of third molars. This severe and sudden pain usually occurs 3 days after tooth extraction and its prevalence is about 68.4%. The undelaying etiology is not known so far. The aim of this study was to assess the effectiveness of chlorhexidine gel (0.2%) in prevention of dry socket and pain following mandibular third molar surgery. This study was performed as a sequential split machted randomized double blind clinical trial. All subjects were 18-45 years of age and they were indicated to extract impacted lower third molars bilaterally with difficulty degree of 7-10 according to Pederson scale. The Patients were randomly assigned into case and control groups. 0.2% chlorhexidine gel was applied by gel foam in the sockets. The incidence of dry socket was measured by Blum scale and VAS scale was used to evaluate the pain level. The results were analysed by chi-square, Mann-u-whiteney and McNemar Tests. This study was performed on 80 patients (160 samples), with average age of 21.58±2.49. The incidence of dry socket in the control group was 32.5% and 11.2% in the experimental group (p<0.005). The pain on the third day was 3.38±1.14 in the control group and 2.32±1.15 in the case group which indicated a 31% elevation in the control group (p<0.01). 0.2% chlorhexidine gel can reduce the incidence of dry socket and pain after the extraction of the Impacted lower third molar teeth.

Topical NSAIDs have been shown to be effective in treatment of recurrent aphtous stomititis. Therefore, the purpose of the study was to compare the effect of Triamecinolone asetonide and diclofenac in patients with recurrent aphtous stomititis referred to Shahed dental school in 2011. In this clinical trial Study 25 patients were divided in two groups (12 persons in control-triamcilonone group and 13 persons in case- diclofenac group). All patients were asked to apply the drug 3 times daily and the effect of therapy was assessed in 0, 2 and 6 days after start of the therapy. Pain level, disease period and ulcer size were compared with in each group and also between case and control groups. Patients in both groups were matched according to the personal and disease specifications. Pain level in day 6 in diclofenac group was 1/6±2/6 and in triamcinolone group was 1/5±2/8 (p<0/9). Ulcer size and treatment results were similar in both groups (p<0/7). It seems that both drugs have similar effects. However, considering the corticosteroid side effects, we recommend topical diclofenac therapy in patients with recurrent aphtous stomititis. Moreover, additional research is suggested to compare the effectiveness of the two drug.

Radiography is important as a paraclinical guide for choosing a proper surgical method and avoiding root fracture during surgery. The aim of the present study was to determine the accuracy of Dental panoramic radiography in assessment of third molars, in patients referred to oral radiology department of Islamic Azad university, dental branch, Tehran In 2010. This diagnostic clinical trial study was performed on 80 third molars. Impaction status, number of roots, fusion and root curvature was assessed on radiographs before surgery by two observers, and compared with surgical findings after operation. Acceptable range for root curvature was considered ±10 degrees difference between radiographic and clinical observation. Statistical analysis was performed using ratio tests. 133 roots were assessed. The root curvature was 154 ±21.9 degree and 81.2% were in acceptable range. Radiographic predictive value for diagnosing impaction, root's fusion and having single root was 100%, 79% and 73.3% respectively and for tooth eruption, root separation and multiple roots was 98%, 86.6% and 98% respectively. Highest and lowest predictive values were found to be for the diagnosis of tooth impaction (100%) and single root tooth (73.3%) respectively. Our results showed that dental panoramic radiographs have relatively high diagnostic precision for assessment of third molar status and morphology

Due to ecologic alterations, white spot lesions in orthodontic patients have a high prevalence. The aim of this study was to determine the prevalence of white spot lesions in orthodontic patients and possible related factors.

The study was designed as a cross- sectional investigation. 200 patients were recruited and demographic data including gender, age, time of brushing, use of dental floss, parents’ educational level and use of fluoride were collected in a questionnaire. The labial surface of incisors, canines and premolars were next inspected for white spots and their frequency calculated. The possible association between the frequency of white spots and aforementioned factors was analyzed via the binary logistic regression test.

90.5% of patients had at least one tooth with white spot. The highest prevalence of white spots was found in upper laterals, and lower first premolars. The duration of orthodontic treatment had the highest association with the development of white spot (P<0.0001). Frequency of brushing and application of fluoride significantly decrease the incidence of white spots (P=0.008), (P=0.003) Respectively. Type of brush and flossing and sex and age of patients showed no statistically significant contribution. Patients with high parents', educational level had more prevalence of white spot (P<0.006).

The prevalence of white spots in patients undergoing fixed orthodontic treatment is high. Administration of fluoride products and increasing brushing sessions could possibly reduce the incidence of white spots

Diabetes Mellitus (DM) is a complex metabolic disorder. The determination of saliva components in these patients may be useful in further understanding the oral finding in this condition. The aim of this study was to evaluate the salivary Alpha- Amylase level in type II diabetic patients.

In this case- control study, 40 patients with type II DM and 40 healthy subjects were selected. All participants were matched for age and sex. Dental and oral status was assessed for all subjects. Whole unstimulated saliva samples were collected during 5 minute to determine salivary flow rate and amylase concentration. The data was analyzed using t-test.

Salivary alpha- amylase rate was significantly higher in patients with type II DM (106217.5±77661.24 Vs. 68257.5±29276.12IU/dl), (P= 0.05), Salivary flow rate was significantly lower in type II diabetic patients than control group (0.32±0.14 Vs. 0.39±0.17),(P=0.001). Dry mouth, burning sensation and DMFT index were significantly higher in type II DM patients (P=0.003).

Salivary alpha amylase level was significantly higher in type II diabetic patients

Temporomandibular Disorder (TMD) was generally Presumed to be a condition affecting only adults. However, epidemiological studies have reported incidences of TMD to be just as high in children. The purpose of this study was to assess the prevalence of signs and symptoms of TMD in children aged 7-9 years in schools of Tehran in 2010. In this descriptive study 400 subjects (Male195- Female205), 7-9 years of age in schools of Tehran were (sampling multi stage) randomly selected. The questionaire was completed by all the individuals and clinical examination was carried out with Research Diagnostic criteria. Prevalence of TMD in samples were determined and the relationship between relevant factors like bruxism, posterior crossbite, anterior open bite, deep bite, Trauma gender and occlusal problem was evaluated by chi Square analysis. our study indicated that at least one sign and symptom was present in 65.2% of Children. Bruxism, Class III, deep bite were significantly related with TMD (P<0.05). There is a high prevalence of TMD in pediatric patient due to: lack of parental attention, misdiagnosis by medical professional, and inability of pediatric patients to properly explain and identify their symptoms.

Tongue lesions are considered as an important part of oral lesions. The aim of this study was to determine the prevalence of tongue lesions in Qazvin high school students in 2010. This cross-sectional study was performed on 2000 high school students in 2010. Direct observations were done by dental mirror, explorer, tongue blade and torch. Lingual lesions (Fissured tongue, Geographic tongue, Hairy tongue, Ankyloglossia, Median rhomboid glossitis, Microglossia, Macroglossia) were diagnosed clinically. Prevalence of the lesions was stated by the 95 percent probability and the role of related factors was evaluated by x2 analyses. The prevalence of tongue lesions was determined as follow: fissured tongue (11.8%) the highest prevalence, Geographic tongue (7.4%), Macroglossia(6.2%),Ankyloglossia(4.2%), Hairy tongue (2%), Median Rhomboid glossitis(0.8%), Microglossia(0%). The total number of subjects with tongue lesions was 592(30.3%) with 54% males and 46% females. Comparison between the sexes, revealed statistical significances.(Pvalue<0.05) Incidence of tongue lesions among Qazvin students is considerably high and these lesions were more prevalent in male students

The thickness of healthy gingiva varies from subject to subject. This variation is not only influenced by genetic factors, but also by tooth size, shape, position and biological phenomena such as natural growth, geneder and age. The purpose of present study was to determine the thickness of facial gingiva among periodontally healthy patients in association with age, gender, tooth type and dental arch. In this descriptive study, 80 individuals (40 male and 40 female), 16-34 years of age with healthy periodontium were chosen. Gingival thickness was assessed in the maxillary and mandibular teeth by Transgingival probing at 2 sites per tooth: Midbuccal and Inter dental papilla. Data were analyzed with Paired-t-test and Anova Test. The thickness of gingiva was found to be significantly higher in the younger age group (16-24) compared to the older age group (24-38) (p=0.005). Male subjects had significantly thicker gingiva compared to female subjects in MB area (p= 0.007).The thickness of facial gingiva in the mandible (1.46± 0.38) was significantly thicker than maxilla (1.23± 0.27). The molars had the thickest and canines had the thinnest gingival thickness. (P=0.005). The results of the present study showed that the facial gingival thickness in the male is more than female, in the mandible more than maxilla and in the Molar region has the most and the canive region has the least thickness.

Diverse prevalence of oral mucosal lesions has been reported among different populations. There are few researches about the prevalence of oral mucosal lesions in Iran. The aim of the current study was to investigate the prevalence of oral mucosal lesions and associated factors in pathology department of Tehran Cancer Institute of Imam Khomeini Hospital from 2000 to 2010. This research was conducted on existing data. The patients’ age, gender, site of the lesion, type of the lesion and microscopic diagnosis were recorded. Prevalence of lesions were evaluated with (CI=%95) all data were analyzed by x2 Test under spss (16). Oral mucosal lesions were present in 784 cases out of 40092 cases (1.96%). Epithelial lesions were found to be the most prevalent oral mucosal lesions of all (90%). The most common location reported for the lesions was the lips (26.8%).The mean age for the patients was 43±17 years of age and there was no association found between the type of the lesion and the sex of the subjects (p<0.09). Squamous Cell Carcinoma was the most prevalent mucosal lesion which is a malignant epithelial tumor and its early detection is essential.