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Background and Objective: Impacted molars teeth, especially third molar, are important in most branches of medical sciences. The angular position of molar teeth is in side effects and therapeutic regiment. This study was conducted to determine the angle of the impacted mandibular third molars. Materials and Methods: This descriptive study was carried out on 429 patients (269 men and 160 women) selected for surgery on impacted mandibular third molar in the oral and maxillofacial surgery clinic in Gorgan, Iran during 2010-11. Pre-operative diagnosis was done by physical examination and OPG radiography. Demographic characterstics including age, gender, ethnicity, impaction angle were recorded for each subject. Data were analyzed using SPSS-16, independent t-test and chi-square test. Results: Totally, 480 impacted third molars were studied. Mean age of patients was 26.06±6.21 years. Impaction of the third molar was more prevalent among men (62.7%) than women (38.30%). Impacted mandibular third molar of 189 people (44.1%) were in left side in 200 people (46.6%) were in right side and in 40 people (9.3%) were bilateral. According to impaction angle, mesioangular (41.7%) and distoangular (3.5%) types had the highest and the lowest frequency, respectively. In bilateral cases, the mesioangular-mesioangular type (48.8%) was the most prevalent. The mesioangular type was the most prevalent in all ethnic groups. The most prevalent angular position of the impacted third molar was the mesioangular type in both sexes. Conclusion: This study showed that the most prevalent angular position of impacted mandibular third molar is the mesioangular type.

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Background and Objective: Gum diseases and dental caries are the most prevalent diseases in societies with different cultures particularly among pregnant women. This study was done to evaluate the oral health status of pregnant women in Gonbad Kavous, northern Iran.

Methods: This descriptive - analytical study was conducted on 400 pregnant women aged 20 to 40 years old in Gonbad Kavous, northern Iran during 2010-11. Demographic and oral examination information was recorded in a chick list. The obtained data were evaluated by DMFT index (Decay, Missing, and Filling Teeth) and OHI-S index (Oral Hygiene Index-Simplified).

Results: The average of DMFT index was 3.29±6.21. There was a significant difference between the place of birth and place of residence of pregnant women with DMFT index (P<0.05). The average of OHI-S index in pregnant women was moderate (0.88±1.36). There was a significant difference between the location of residence and the level of education of pregnant women with OHI-S index (P<0.05). The most important factor to increase DMFT index was the high average of decayed teeth among pregnant women. Regarding the method and duration of observing oral hygiene, the most correct answers were related to method of cleaning teeth (toothbrush and toothpaste) and the least ones were related to the duration of cleaning (3-5 minutes).

Conclusion: DMFT index was high in pregnant women in northern Iran.

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Background and Objective: Maxillary sinus gradually extends laterally and inferiorly during pneumatization, and lamina dura of molar and premolar teeth can make a part of sinus floor. Knowledge about this anatomic relationship is essential to prevent complications paticularly iatrogenic perforation of sinus floor. Limitations of periapical and panoramic radiographs to visualization of this relationship led to the usage of cone-beam computed tomography (CBCT). This study was aimed to evaluate the vertical and horizontal relationship between roots of maxillary molars and sinus floor in CBCT images.
Methods: In this descriptive cross sectional study, ninety-five samples were selected of patients in Department of oral and maxillofacial radiology in Tabriz, Iran using simple randomization. Mean age of patients was 32.5 years old. Images were made by VGi cone beam Newtom and reconstructed by NNT viewer version 2.17. The vertical and horizontal relationship between roots of 139 maxillary first and 126 second molar teeth and floor of sinus evaluated.
Results: Type 2 was the most common relationship among the first and second molars, vertically (the inferior wall of the sinus located below the level connecting the buccal and palatal root apices,without an apical protrusion) and horizontally (the alveolar recess of the inferior wall of the sinus located between the buccal and palatal roots). There was a significant relationship between the type of tooth and sinus floor (P<0.05).
Conclusion: Most of the maxillary molar roots were in contact with sinus floor and sinus floor was extended mostly between buccal and palatal roots vertically and horizontally, respectively. Attention to sinus involvement possibility during interventions in maxillary molar region is important.