1 143 Radiology Pharyngeal Airway: An Analysis Using 2D vs. 3D Images in Different Malocclusions Bronoosh Pegah b Khojastepour Leila c Charlie Mohammad Shabnam d b Department of Oral and Maxillofacial Radiology, Dental School, Shiraz University of Medical Science, Shiraz, Iran c Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Shiraz University of Medial Science, Shiraz, Iran. d Dental school, International Branch, Shiraz University of Medical Science, Shiraz, Iran 1 12 2014 3 4 1 6 04 07 2015 04 07 2015 Introdouction: The aim of this study was to compare information regarding pharyngeal airway sizes in adolescent subjects with different malocclusion classes obtained from lateral cephalograms and 3–dimensional (3D) cone-beam computed tomography (CBCT) scans. Materials and methods: In this prospective cross-sectional study, CBCT scans and lateral cephalograms of 35 subjects, taken within one week, were included. Measurements of the pharyngeal airway area from the lateral cephalograms and airway volume from the CBCT scans were analyzed using one-way ANOVA post-hoc tests were used for comparison of the airway area and volume in different malocclusion classes. A linear regression of the airway area to volume was performed to discern associations and determine correlation coefficients. Descriptive statistics for airway dimensions were determined. Results: No significant differences were detected between the sexes for any measurement therefore, all data were combined. Regression analysis showed that for every mm2 increase in airway area, there was a corresponding 11.94- mm3 increase in mean airway volume. One-way ANOVA and post-hoc tests demonstrated significant differences in airway area and volume between the three malocclusion classes (p < 0.001). The highest mean airway area and volume was observed in class III malocclusion, followed by classes I and II malocclusion. Conclusion: Pharyngeal airway area, as measured on the lateral cephalogram, concurs with volumetric data. However, accurate determination of airway volume and shape is achieved by 3D imaging, owing to great variability in the shape of the pharyngeal air space.
144 Radiology Developmental Stages of Third Molars in 16- to 22-year-old Patients Referred to a Clinic in Rafsanjan, Iran using Demirjian and Modified Gleiser and Hunt Methods Tafakhori Zahra e Kamali Ali f Nemati Somayeh g e Department of Oral and Maxillofacial Radiology, School of Dentistry and Dental Research Centre, Rafsanjan University of Medical Sciences, Rafsanjan, Iran f School of Dentistry and Dental Research Centre, Rafsanjan University of medical sciences, Rafsanjan, Iran. g Department of Maxillofacial Radiology, Faculty of Dentistry, Guilan University of Medical Sciences, Rasht, Iran 1 12 2014 3 4 7 14 04 07 2015 04 07 2015 Introdouction: Age estimation is an important issue in forensics, particularly for treatment planning and determining patients’ rights. Radiographic evaluation of the third molar developmental stage is a significant criterion for age estimation. The pattern of tooth development is largely heritable and varies from race to race. The objective of this study was to radiographically examine and compare the developmental stages of the third molars with the chronological age of Rafsanjan’s young individuals. Materials and methods: This cross-sectional study was performed on 215 patients aging 16–22 years that presented to a private oral and maxillofacial radiology clinic in Rafsanjan, Iran for panoramic radiography. Using the panoramic radiographs, the developmental stages of the third molars were determined and recorded using two methods: the Demirjian and Modified Gleiser and Hunt methods. The data thus obtained were statistically analyzed mean age of each developmental stage for each sex was determined and regression equations for age estimation were calculated. Results: In both developmental classification methods, males preceded females in terms of dental development (P < 0.001). Furthermore, there were strong correlations between teeth 18 and 28 and between teeth 38 and 48 in both males and females by either method (P < 0.001). Chronological age was acceptably predicted on the basis of the gender and developmental stages of the teeth 28 and 48 using both methods (R2 = 45.4%, Demirjian method R2 = 42.5%, Modified Gleiser and Hunt method). Conclusion: The results suggest that third molar developmental stages studied using panoramic radiographs could be suitable for estimating chronological age. 145 Radiology Eruption time of the first Primary Tooth and its Relationship with Growth Parameters in Children Vejdani Javaneh h Heidarzade Abtin i Darkhaneh Seyed Mohammad j h Department of Pediatric Dentistry, Guilan University of Medical Sciences, Dental School, Rasht, Iran i Guilan University of Medical Sciences, Rasht, Iran j Guilan University of Medical Sciences, Dental School, Rasht, Iran 1 12 2014 3 4 15 19 04 07 2015 04 07 2015 Introdouction:Tooth eruption is recognized as an important aspect of human growth and development. It can be influenced by a number of factors, and it may reflect the general development of a child’s body. The purpose of this study was to determine the age at which the first primary tooth erupted and its relationship with height, weight and head circumference in 3-15-month children in the city of Rasht,Iran. Materials and methods: This descriptive, cross-sectional study was conducted on 648 children (288 girls and 360 boys) aged between 3–15 months, which were randomly selected from all health care centers in Rasht (the children visit these centers regularly for vaccinations). Height, weight, and head circumference were measured on the same day. From the obtained data, descriptive statistical indices were calculated for the eruption time of the primary central incisors. Cox regression analysis was used to determine the relationship between tooth eruption and the three growth parameters. Results: The timing of the eruption of the first primary tooth ranged from 5 to 14 months. The first erupted tooth was the mandibular central incisor, with the mean age of eruption of 9.93 ± 0.11 months in girls and 10.13 ± 0.1 months in boys. There was a significant association between the eruption time of the first primary tooth and weight-for-age in both girls and boys. The relationships of first primary tooth eruption with head circumference-for-age and height-for-age were significant only in boys. Conclusion: The first primary tooth erupted earlier in girls than in boys, and primary tooth eruption was significantly related to the measured growth parameters, i.e., height, weight, and head circumference. 146 Radiology Associations between Impaction Depth of the Mandibular Third Molar and Pathological Conditions Mokhtar Ali k Bronoosh Pegah l Haghnegahdar Abdolaziz m k Islamic Azad University, Dental Faculty , Tehran ,Iran l Alborz Radiology Center , Karaj, Iran m Shiraz University of Medical Sciences, Oral and Maxillofacial Radiology Department, Shiraz, Iran 1 12 2014 3 4 20 25 04 07 2015 04 07 2015 Introdouction: Impacted and partially erupted third molars can cause various symptoms and pathologies. The aim of this study was to determine the association between commonly observed pathological conditions and the impaction depth of lower third molar teeth. Materials and methods: In this retrospective study, 370 panoramic radiographs including 724 lower third molars were evaluated to assess several pathologies according to impaction depth. The patients were also examined clinically for pericoronitis. Impaction depth was defined according to horizontal indices in class I, II, or III, where none, less than half, or more than half of the crown was in the ramus of the mandible, respectively. The vertical indices for teeth, classes A, B, and C, were defined by the highest portion of the tooth being on a level with or above the occlusal plane, below the occlusal plane but above the cervical line of the second mandibular molar, or below the cervical line of the second mandibular molar, respectively. The data were analyzed using Chi-squared tests. Results: Of the teeth analyzed, 57%, 28.4%, and 14.6% were at vertical level A, B, and C, respectively. Of the 605 mandibular third molars, 363 (60%) were in horizontal class I, 212 (35%) were in class II, and 31 (5%) were in class III. Incidence of pericoronitis was significantly associated with partially erupted third molars and impactions of class AII (P = 0.028). Class A impaction showed a stronger association than classes B or C with all conditions (P = 0.04) except for bone loss and root resorption of second molars (P = 0.07). Conclusion: Class A impaction depth, where the highest portion of the tooth was on a level with or above the occlusal plane, was associated with more pathological conditions than classes B or C. 147 Radiology Evaluation of the Elongation and Calcification Patterns of the Styloid Process with Digital Panoramic Radiography Khojastepour Leila n Dastan Farivar o Ezoddini Ardakani Fatemeh p n Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Shiraz University of Medial Science, Shiraz, Iran o Department of Oral and Maxillofacial Radiology Faculty of Dentisty, Shiraz University of Medical Sciences, Shiraz, Iran p Department of Oral and Maxillofacial Radiology Faculty of Dentisty, Shahid Sadough University of Medical Sciences Yazd, Iran 1 12 2014 3 4 26 31 04 07 2015 04 07 2015 Introdouction:The styloid process(SP) has the potential for calcification and ossification. The aim of this study was to investigate the prevalence of different patterns of elongation and calcification of the SP. Materials and methods: In this cross-sectional study, 400 digital panoramic radiographs taken for routine dental examination in the dental school of Shiraz University were evaluated for the radiographic features of an elongated styloid process (ESP). The apparent length of SP was measured with Scanora software on panoramic of 350 patient who met the study criteria, ( 204 females and 146 males). Lengths greater than 30mm were consider as ESP. ESP were also classified into three types based on Langlais classification (elongated, pseudo articulated and segmented ). Data were analyzed by the Chi squared tests and Student’s t-tests . Results: ESP was confirmed in 153 patients including 78 males and 75 females (43.7%). The prevalence of ESP was significantly higher in males. 53.8% of males and 36.8% of female patients has ESP (P value < 0.05 ). ESP was also significantly more common in the older age group (p < 0.05). There was no statistically significant difference between the occurrence of unilateral and bilateral ESP (p > 0.05).Type I and Type II ossification pattern had almost equal frequency ( 42.5% and 43.8% respectively) Conclusion: ESP and calcification of stylohyoid ligament can be easily detected in panoramic radiograghs and is more common in older patients. 148 So on Endodontic Retreatment of a Maxillary First Molar with Unusual Palatal Root Canal Morphology: A Case Report Ghotbi Rad Seyed Faroogh Havaei Seyed Roholla Mousavi Elnaz Kazemian Reza Department of Endodontics, Zahedan University of Medical Sciences, Zahedan, Iran Department of Endodontics, Zahedan University of Medical Sciences, Zahedan, Iran Department of Endodontics, Guilan University of Medical Sciences, Guilan, Iran Department of Endodontics, Zahedan University of Medical Sciences, Zahedan, Iran 1 12 2014 3 4 32 35 04 07 2015 04 07 2015 Introdouction: Variations in root canal morphology pose a challenge for successful endodontic treatment. The root canal anatomy of the maxillary first molar has been often described as three roots with four canals (two mesiobuccal, one distobuccal, and one palatal). The occurrence of two palatal canals in one palatal root is quite rare. This report represents the case of a maxillary first molar with unusual canal morphology in the palatal root and highlights the importance of thorough root canal exploration for successful endodontic treatment.