[Effect of translucency and opacity of fiber reinforced posts on fracture resistance of compromised teeth]

Severely damaged teeth with no support at the coronal portion of root canal are very difficult to restore. The aim of this invitro study was to evaluate intraradicular reinforcement by dual cure composite resin and two different types of fiber reinforced composite [FRC] posts [translucent and opaque] in structurally compromised roots. Root canal therapy was performed for 48 maxillary central incisors. The teeth were divided into four groups, and specimens from three groups were prepared to simulate the teeth with flared canals. In the 1[st] group, no weakening was done. In the 2[nd] group, the compromised area of the root canal was filled with gutta percha. In the 3[rd] and 4[th] groups, universal DT light and DT white posts were used respectively in the root canal to 8 mm below the margin of the palatal wall. The posts were cemented with dual-cure composite. In all groups, the access cavity was restored with light-cure compo-site resin. After being mounted, all specimens were pressed at an angle of 45? relative to the long axis of the teeth. The amount of force at fracture was recorded. Results of fracture load were evaluated by one-way ANOVA and LSD post hoc test and the results of mode of fracture were evaluated by chisquare test. The mean fracture load for the four groups was 170.12, 71.40, 125.8 and 148.59 kgf, respectively. There was a significant difference between the mean fracture load of 1[st] and 2[nd] groups and that of other groups [P=0.001]. The mean fracture load of the 4[th] group was significantly [P=0.002] higher than that of the 3[rd] group. The frequency of restorable fractures was significantly different between these two groups [P<0.001]. Using dual cure composite resin and FRC posts in roots with thin walls will reinforce the compromised teeth but the type of post will affect the outcome

Abnormal temporomandibular joint radiographic findings in patients referred to department of oral and maxillofacial radiology, dental school, Shahid Beheshti University of Medical Sciences

Temporomandibular Joint disorders are relatively frequent in different societies. The purpose of the present study was to determine abnormal Temporomandibular Joint radiographic findings in patients referred to Dental School, Shahid Beheshti University. This descriptive cross-sectional study was done on 400 patients with no marked symptoms of temporomandibular joint disorders who met criteria of the study. Mean age of patient was 38.38. The data was collected by taking patients history, clinical evaluation while the panoramic radiographies were taken in standard conditions viewing by means of black-colored sheets .for statistical evaluation data was analyzed by chi- square and exact fisher tests. Flattening was the most observed abnormal finding with 16.3% incidence. Erosion, condylar hyperplasia, concavity, Bifid condyle,condylar hypoplasia and sclerosis respected were the most common abnormal findings in this study. There were no significant differences in the incidence of abnormal findings regarding the patient's gender, dental status and occlusion, but the prevalence of abnormal radiographic findings was significantly uprising as the age of the patients increased [P< 0.002]. The results demonstrated the incidence of abnormal radiographic findings in 34.4% of the patients referring to the studied center which shows a relatively high prevalence

[Comparison of cytological findings of the buccal mucosa between smokers and non smokers]

In the past few years an alarming rise in the occurence of oral and oropharyngeal squamous cell carcinoma which now comprises 3% of all cancers in men and 2% of all cancers in women has been seen. Tobacco smoking is a single most well-known and important risk factor for squamous cell carcinoma in oral cavity. However, the pathogenesis, especially the initial changes brought about by smoking is not fully understood. The aim of this study is to compare cytological findings of apparently normal buccal mucosa among smokers and nonsmokers based on samples obtained by brush biopsy. Thirty-eight smokers and 42 nonsmokers, who did not show any conspicuous oral lesions were evaluated in a cross-sectional study. The specimens were taken from healthy and apparently normal buccal mucosa by a commercial cytobrush. Cytologic evaluation of biopsy specimens in terms of frequency of dysplasia/neoplasia, granular cells, binuclear cells, coarse chromatin, clear nucleus, apoptotic cells, pleomorphism in nuclear and cytoplasmic morphology was performed. Chi square test was used for comparison and analysis. Studied samples included 80 men [mean age, 40 years] in both groups. There was no dysplastic or neoplastic changes in any of the groups. Cytologic studies demonstrated that clear nucleus, coarse chromatin and the frequency of nuclear pleomorphism showed statistically significant differences between the two groups [P<01, P<001 and P<01 respectively]. Buccal mucosa of smokers showed some differences compared to samples from nonsmokers. However, the clinical significance of these changes is uncertain