مجله دانشکده دندانپزشکی مشهد
سال سی و پنجم شماره 1 (پیاپی 76، بهار 1390)

Numerous studies report the prevalence of tooth absence, extra tooth, and double tooth (fusion & gemination) in anterior primary teeth as being just less than 1%. Due to low prevalence of such anomalies, little attention is paid to them. There are concrete effects on corresponding permanent teeth and developing occlusion in about 50% of these cases. The aim of the present study was to determine the frequency of such problems in 113 cases, and to discuss the effect of these anomalies on the permanent successors A total of 113 cases of the different 4 types of anomalies (39 cases of fusion, 14 cases of gemination, 39 cases of missing, and 21 cases of supernumerary teeth) were studied. The cases were among the patients referring to the author’s private clinic during the past 20 years for whom an appropriate radiography had been performed. The cases with tooth absence due to extraction or trauma were excluded. The results of the study were descriptively analyzed and reported. In the present study, the distribution of the anomalies including 39 cases of fusion, 14 cases of gemination, 39 cases of issing, and 21 cases of supernumerary teeth based on sex, maxillary and mandibular arches, tooth type, being unilateral or bilateral, as well as the impact of each on the succeeding permanent teeth were reported. The results show that the highest prevalence of fusions was seen in the central and lateral mandibular teeth, while in gemination, the cases were higher on maxillary teeth. All supernumerary teeth were seen in the maxillary arch, while there was a good balance for the missing tooth in both arches. In almost 50% of the cases, the presence of fusion in primary teeth was accompanied with a missing of permanent tooth; yet in gemination, the number of permanent teeth was normal. Finally, in almost half of the cases with supernumerary tooth, there was supernumerary tooth in permanent dentition. The results in this study is valuable indicating that tooth radiograph is helpful in evaluating the number of anterior permanent teeth in case such anomalies exist; Thereby, suitable treatment plans for the future could be established.

Age estimation of the children usually is assessed using tooth developmental stages in radiographs. The Demirjian’s method is one of them. This study was done with the aim of assessment of the Demirjian’s developmental age stages of the permanent mandibular teeth in panoramic radiographs of 6-13 years old patients attended to Radiology Department of Mashhad dental school. In this descriptive cross-sectional study, a sample of 310 orthopantomographs taken from 169 girls and 141 boys between 6 and 13 years old referred to Mashhad dental school was selected. The chronological age of each child was calculated by subtracting her or his birth date from the date on which the radiograph had been obtained and the developmental stages of each of the seven left mandibular permanent teeth were recorded using the Demirjian method. Independent-sample t test was applied for comparison of the mean age of different developmental stages in both genders. The mean chronological age of stage G of teeth 32 and 33, stage F of tooth 34 and stages D and F of tooth 35 was different between the two genders (P<0.05). The mean chronological age of teeth 31, 36 and 37 in both sexes and in different developmental stages showed no statistically significant difference (P>0.05). The mean ages of different developmental stages of permanent mandibular teeth using the Demirjian method were similar to former studies. Also, the stage of mandibular teeth development was higher in girls than boys with similar chronological ages. Key words:

Management of postoperative bleeding in patients receiving warfarin, has always been one of the most challenges for dentists. Cessation in using warfarin 2-3 days before tooth extraction is one of the methods for preventing bleeding in these patients, but it may increase the risk of thromboembolism. The aim of this study was to use localized haemostatic drugs instead including gelatin sponge and tranexamic acid mouthwash. In this clinical trial study, 22 patients who were currently receiving warfarin with INR range of 2-4 were selected. For each patient 3 teeth were extracted in several times. After extraction of each tooth, Gelatin sponge, Tranexamic acid 4/8% mouth wash and sterile gauze (without any haemostatic drug) were used.Tendency of bleeding in 66 teeth, 2 and 24 hours after extraction was checked. No suture was used for any patient. Data were analyzed with descriptive statistics (frequency and average) and Chi-square and Fisher's exact tests. Rate of bleeding in three groups were measured: Gelatin sponge: 9.1%, Tranexamic acid 4.8% mouthwash: zero and sterile gauze (without any haemostatic drug): 27.3%. In patients treated with warfarin, interruption in use of warfarin for tooth extraction is not needed. Local haemostasis with tranexamic acid 4.8% mouthwash without any suture is sufficient.

No question exists about the diagnostic utility of radiographic examinations in detection of disease and in monitoring the progression of the disease. Although the diagnostic information provided by radiographs is valuable, practitioners must be aware of the harmful effects of ionizing radiation and familiar with the principles of radiation protection. The aim of this study was to evaluate the knowledge of general dentists about radiation protection in oral radiographic examination in the city of Rasht. This descriptive cross-sectional study was done on 110 general dentists in Rasht. Information about demographic and individual characteristic of the dentists, and their knowledge related to the radiation protection in oral radiographic examinations were obtained by a questionnaire. Then statistical analysis of the data was performed by ANOVA. 68.2% of dentists were male and 31.8% were female. 53.6% had more than10 years in practice. Only 12.7% of them worked in group practice and 73.6% had not had attendance in any education course in oral radiology since graduation. The mean score of total dentist's knowledge was 13.66±4.09 out of 27. Gender, working in group practice or private practice, years in practice and attendance at educational courses in oral radiology had no significant association with knowledge (P>0.05). in the present study, the results indicated that knowledge level of Rasht general dentists concerning the radiation protection is moderate and attempts should be made to improve knowledge of dentists about radiation protection.

Ameloblastoma is a benign epithelial odontogenic tumor that exhibits a more aggressive behavior than follicular cyst and keratocystic odontogenic tumor. The purpose of the current study was detection and evaluation of microvessel density (MVD) effect on growth and clinical behavior of above odontogenic lesions with immunohistochemistry. In this descriptive-analytic cross-sectional study, 45 paraffin blocks of mentioned lesions were selected and stained immunohistochemically with CD34. The mean MVD of each lesion in three microscopic fields was calculated separately and was evaluated in the two areas, adjacent and far from odontogenic epithelium and then were compared with one another. Mann-Whiteny and Kruskal Wallis tests were used for the statistical analysis. Mean microvessl density was 40.8±15.9, 25.4±5.3, and 9.4±3.52 in ameloblastoma, keratocystic odontogenic tumor, and follicular cyst, respectively.Mean microvessl density difference between the above mentioned lesions was statistically significant (P<0.001). In all the odontogenic lesions, the microvessel density adjacent to odontogenic epithelium was higher than the areas far from the epithelium (P=0.001). The increase in microvessel density in ameloblastoma compared to keratocystic odontogenic tumor and follicular cyst can be one of the main factors in ameloblastoma aggressive behavior. Angiogenesis adjacent to odontogenic epithelium has a more prominent role in growth of follicular cyst and progression and aggressive behavior of odontogenic tumors.

Mandibular prognathism is one of the most common skeletal disorders in Iranian population and so mandibular setback surgery is one of the most common surgeries in Oral & Maxilllofacial area. Ramus Sagittal Osteotomy is one of the surgeries which is done for the purpose of mandibular setback or advancement. The purpose of this study was to evaluate the progress of maximum mouth opening (MMO) after bilateral sagittal split osteotomy (BSSO) surgery in patients with mandibular prognathism. In this study, 36 patient's undergone BSSO surgery with Hunsck technique in order to correct mandibular prognathism, were taken into consideration. In all patients, fixation was done with three titanium screw in each side. Maximum mouth opening was measured before surgery and within 1, 3, 6 months after surgery. Repeated measurement was performed for data analysis (=0.05). In the patients 81.32% of maximum mouth opening was gained after one mouth, 92.1% after three months and nearly total recovery (98.94%) after 6 months of surgery. The results confirm the concept that limitation in MMO is not a long lasting complication in bilateral sagittal split osteotomy surgery in patients with mandibular prognathism and it would approximately be as same as before surgery after six months.

Chondrosarcoma is a malignant tumor of cartilaginous origin. The most common type in the jaw is mesenchymal. Chondrosarcoma in maxillofacial region is an uncommon tumor and maxilla is more commonly affected than mandible. The aim of this paper is case report of a rare chondrosarcoma of the mandible. Case report: A 65-year-old woman was referred to Oral Medicine Department of Mashhad dental school with swelling over the buccal and lingual aspect of the anterior mandible. Swelling had been present for 1 year and had increased gradually in size over time. The patient did not have any systemic disase and was not currently taking any medications. Extraoral examination did not reveal any obvious facial swelling, asymmetry or cervical lymphadenopathy. Intraoral examination revealed an exophitic nodular and tendered lesion with smooth and purple surface. It was firm to rubbery in buccal aspect and bony in lingual surface with 3×3.5 diameters. Occlusal and panoramic radiographs revealed the multilocunar well defined and mixed radiolucent-redioopaque lesion from right mandibular first premolar to left mandibular first premolar. Subperiosteal ossification is revealed in the occlusal cross sectional radiography. Histopathological examination revealed chondrosarcoma (grade I). The patient was advised to undergo surgery, and the tumor was resected by segmental mandibulectomy. Clinical and radiographic feature at chondrosarcoma are varied, the incidence of this lesion in unusuall location like anterior of jaw with a well-delined feature and ossification could lead to clinican error and delaying treatment. Considering age, course and invasion could be helpful in diagnosis.