Frontal Sinus Fractures: An Evaluation of Patient Demographics, Mechanisms of Injury, Classification, and Management Strategies in Patients Referred to a Trauma Center, From 2014 to 2019.

This retrospective study aimed to present demographic data, mechanisms of injury, anatomical locations, and management strategies in patients with frontal sinus fractures. The study included 91 patients with frontal sinus fractures attending the Rajaee Hospital of Shiraz between 2014 and 2019. The data recorded for each patient included age, sex, injury mechanism, fracture classification, associated craniofacial fractures, nasofrontal duct injury, cerebrospinal fluid leak, and treatment approach. The mean age of patients was 31.0±14.0 years, with male predominance (95.6%). Car crashes represented the most frequent mechanism of frontal sinus fracture, involving 31 subjects (34%). Isolated anterior and posterior table fractures were seen in 32 (35.2%) and 5 (5.5%) patients. Fifty-four patients (59.3%) presented both tables' involvement. Frontal sinus injuries occurred frequently (74.7%) with other facial fractures. Nasofrontal duct injury was found in 7 patients (7.7%), and 13 (14.3%) exhibited cerebrospinal fluid leakage. Fifty patients (55%) were treated with observation alone; 16 (17.5%) underwent sinus preservation, 12 (13.2%) experienced sinus obliteration, and 13 (14.3%) endured cranialization. Fisher's exact test revealed no significant association between the classification of fracture and the mechanism of injury (P=0.591). However, a significant association was observed between the fracture classification and the treatment applied (P=0.023). Frontal sinus fractures were most often caused by car crashes in young adults. Combined anterior and posterior table fractures were more commonly found than isolated anterior or posterior table involvement. Most frontal sinus fractures were treated conservatively without DDS surgical operation.

Mandibular Canal Branching Assessed With Cone-Beam Computed Tomography.

This study aimed to evaluate the prevalence and type of mandibular canal branching in a sample of the Iranian population through cone-beam computed tomography (CBCT) images. This cross-sectional study was performed on CBCT records of 300 patients (112 males and 188 females; mean age 30.14 ± 10.96 y). The presence of mandibular canal branch (MCB) was evaluated by reconstructing multiple panoramic views and buccolingual cross-sections, according to Naitoh's classification. The prevalence of MCB, the type of MCB, and the demographic information of all patients were recorded. The maximum number of branching and the maximum type of branching were also registered for each patient. Mandibular canal branching was observed in 131(43.7%) of 300 CBCT images without side or sex differences ( P > 0.05). The most frequent type was dental, followed by the retromolar, forward, and buccolingual types, respectively. There was a statistically higher frequency of retromolar canal in females than in males (odds ratio: 1.14 ± 4.25; P = 0.013). About 46% of patients with MCB had more than one accessory canal and 29% displayed more than one type of MCB. The coincidence of dental and retromolar canals in a patient was the most prevalent combination. Considering the relatively high prevalence of MCB (43.7%), it is recommended to keep in mind the possibility of anatomical variations of the inferior alveolar nerve during dental procedures to avoid postsurgical complications. The high possibility of observing multiple numbers and types of branching in the patients should also be considered during preoperative assessments.

Determining the existence of the foramen of Huschke in patients with temporomandibular joint disorders using cone beam computed tomography: retrospective cohort study.

BACKGROUND: Foramen of Huschke has been presented as an unusual developmental defect in anteroinferior aspect of external auditory canal. It can be associated with significant otologic complications. The purpose of this study was to determine the association between existence of foramen of Huschke and temporomandibular joint disorders in Cone Beam Computed Tomography (CBCT) images. METHODS: Of an initial sample of 465 patients, we retrospectively evaluated the CBCT images of 118 individuals with clinical signs and symptoms of temporomandibular joint disorders as case group and 256 individuals as control group. The presence, size and localization of foramen of Huschke were assessed in the axial and corrected sagittal images. The sex and age distribution were determined. Fisher's exact test, T-test and Pearson's Chi-square were applied to assess the relationship between foramen of Huschke and temporomandibular joint disorders in the case and control groups considering age and sex. RESULTS: The foramen of Huschke prevalence was slightly higher in patients with temporomandibular joint disorders (3.4%) than patients without temporomandibular joint disorders (0.8%). However, the difference was not statistically significant (P = 0.082). foramen of Huschke was found in five females and one male. There was no significant difference between case and control groups considering the age of patients with foramen of Huschke (P = 0.683). There was no significant difference between the case and control groups, considering the right and left ears in distribution of foramen of Huschke (P = 0.099) (P = 0.183). CONCLUSIONS: Higher prevalence of foramen of Huschke in patients with temporomandibular joint disorders may suggest possible mechanism for temporomandibular joint disorders development that can be affected by presence of foramen of Huschke.

A Radio-Odontometric Analysis of Sexual Dimorphism in First Molars Using Cone-Beam Computed Tomography.

OBJECTIVE: Different techniques for sex prediction are developed and used in the forensic medicine field. One of these methods is based on the teeth morphometry. The aim of the present study was to evaluate the degree of sex determination of the maxillary and mandibular first molar teeth in cone beam computed tomography images. METHOD AND MATERIALS: This study was carried out on cone beam computed tomography images of 100 men and 100 women with a mean age of 21.28 ± 2.47 years. The roof, floor and height of pulp chamber, as well as marginal enamel thickness and dentin thickness at the height of contour, tooth width, and crown length were measured. Student t test and discriminant analysis were applied to assess the differences in the measured parameters between men and women. RESULTS: According to the present study, the maxillary first molar was more dimorphic than the mandibular teeth. The accuracy of sex identification of mandibular and maxillary first molar tooth was 84% and 77%, respectively. The mesiodistal measured variables were more accurate in sexual differentiation than the buccolingual ones. For sex differentiation, the most dominant variables for maxillary and mandibular first molar teeth were crown height and dentin thickness, respectively. CONCLUSIONS: The first molar tooth showed an acceptable level of sex determination accuracy based on the odontometric measurements.

Evaluation of Zygomaticosphenoidal Angle in Patients With Unilateral Zygomaticomaxillary Complex Fracture.

ABSTRACT: This study aimed to assess the zygomaticosphenoidal (ZS) angle in patients with reducted unilateral zygomatico-maxillary complex (ZMC) fracture and compare it with the normal control group. This study was performed on CT images of 60 cases and 60 controls with a mean age of 35.1 ±â€Š14.6. The ZS angle was measured on axial images containing the equator of the eyeball. Moreover, the mean absolute difference value and asymmetry index were calculated. Chi-square test, independent-sample t test, 1-way ANOVA, paired-sample t test, and ROC curve analysis were applied. The mean ZS angle in the control group was 46.6°â€Š±â€Š3.5°. Considering laterality, the mean of ZS was not significant in the control group. However, after reduction of unilateral ZMC fracture, there was a significant difference between the mean ZS angle in right and left sides. The mean absolute difference between right and left ZS angles was significantly higher in the case group. A threshold number of 0.9° is established in the mean absolute difference value which is the difference between the right and left ZS angles in an individual for detecting asymmetry. The ZS angle can be a useful anatomical aid to guide surgeons in achieving facial symmetry in ZMC fractures.

Evaluation of Maxillary Sinus Characteristics in Patients With Cleft Lip and Palate Using Cone Beam Computed Tomography.

OBJECTIVES: The detection of anatomical variation impairments in patients with cleft lip and palate (CLP) is crucial in combined orthodontic and maxillofacial surgical treatments. Therefore, this study aimed at evaluating the anatomical maxillary sinus characteristics, nasal septum deviation (NSD), and mucosal thickening of the maxillary sinus in patients with CLP using cone beam computed tomography (CBCT). DESIGN: The CBCT images were classified into 3 groups of unilateral cleft lip and palate (UCLP; n = 40), bilateral cleft lip and palate (BCLP; n=14), and noncleft (control; n = 54). Subsequently, the maxillary sinus linear dimensions were assessed. Height, width, depth, infundibulum height, and ostium width were assessed as quantitative measures, whereas nasal septum deviation and mucosal thickening were assessed as qualitative measures. One-way analysis of variance and χ2 tests were utilized to identify any significant differences among the groups regarding the aforementioned variables. RESULTS: Significant differences were observed among the groups regarding maxillary sinus height and depth, NSD, and mucosal thickening. Moreover, UCLP and BCLP groups showed higher incidence of NSD and mucosal thickening. However, the size of maxillary sinus height and depth was lower in the UCLP and BCLP groups. CONCLUSION: The results showed that BCLP and UCLP groups obtained lower maxillary sinus height and depth compared to the control group. On the other hand, incidence of the NSD and mucosal thickening was significantly higher in UCLP and BCLP groups than those in the control group.

Assessment of the relationship between the maxillary sinus and the canine root tip using cone beam computed tomography.

BACKGROUND: The purpose of the present study is to investigate the relationship between the maxillary sinus and the canine root apices in cone beam computed tomographic images (CBCT) and to assess the amount of extension of the maxillary sinus to the anterior region of the jaw in different sexes and age groups. METHODS: CBCT of 300 individuals (154 males and 146 females) over 20 years (with a mean age of 35.12 ± 8.40 years) were evaluated. The subjects were categorized into three age groups (20-30, 30-40, and 40-50 years). When the maxillary sinus extended to the canine area, the vertical distance between them was measured, and their relationship was classified into three types: I (more than 2 mm distance), II (less than 2 mm distance or in-contact), and III (interlock). RESULTS: 413 out of 600 maxillary sinuses (68.8%) were extended into the canine area or beyond. Among them, 15 maxillary sinuses pneumatized into the incisor area (2.5%). The prevalence of the maxillary sinuses extended to the anterior region of the jaw was not significantly different between genders. However, it was significantly less frequent in the older age group and more frequent on the left side. In addition, the mean amount of anterior extension of the maxillary sinus (mm) was significantly lower in the older age group. Type I was the most frequent vertical relationship between the maxillary sinuses and canine apices with no significant difference in gender, side, and age groups. CONCLUSIONS: In most cases, the maxillary sinus extended to the canine area and sometimes reached the incisor region. This necessitates paying more attention to the maxillary anterior sextant during surgical procedures.

Does the Winter or Pell and Gregory Classification System Indicate the Apical Position of Impacted Mandibular Third Molars?

PURPOSE: The present study investigated the relationship of impacted mandibular third molars to the cortical plates and inferior alveolar canal (IAC) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: The present study included CBCT images of 386 lower third molars in 226 patients, for whom the initial panoramic radiographs had revealed a close relationship between the third molars and IAC. The coronal images were prepared to determine the position of apex about the buccal and lingual cortexes and IAC. The impacted third molars were categorized using the Winter and the Pell and Gregory classifications. The relationship between the third molars and buccal/lingual cortexes and IAC was determined in the different classes of the Winter and the Pell and Gregory systems. RESULTS: The mesioangular position was more prevalent in the present sample. Most teeth were Class I concerning the ascending ramus and level C in depth. Generally, the impacted mandibular third molars showed a lingual position and were in contact or intersecting into the IAC. A significant association was found between the type of tooth impaction using the Winter and the Pell and Gregory classifications and the position of the third molar teeth concerning the cortical plates and IAC. CONCLUSIONS: The possibility of the buccal position of the tooth and the chance of an intersection of the apex into the IAC was greater in teeth that were mesioangular and were Class III concerning the ascending ramus and level C in depth. These data should be considered during the preoperative assessment of third molars to reduce postoperative complications.

Analysis of Facial Symmetry After Zygomatic Bone Fracture Management.

PURPOSE: The location of the zygomatic bone plays an important role in facial symmetry and esthetics. The aim of this study was to determine and compare the frequency of facial asymmetry in a sample of patients who had undergone treatment of unilateral zygomaticomaxillary complex (ZMC) fractures (study group) and a sample of patients without ZMC fracture (control group). MATERIALS AND METHODS: This was a retrospective controlled cross-sectional study. The primary predictor variable was the type of ZMC fracture (linear or comminuted). The primary outcome variable was facial asymmetry characterized by the bilateral difference in the position of the malar eminence (ME) in 3 dimensions based on computed tomographic images. The other variables for this study were classified as demographic (age and gender) and anatomic (side of ZMC fracture). Descriptive and bivariate statistics were computed. Statistical significance was set at a P value less than .05 with 95% reliability. RESULTS: The entire sample consisted of 134 patients (n = 67 per group). The mean bilateral difference of the ME position in the study group was markedly greater than in the control group. More than half the study patients had facial symmetry and almost 10% of them had marked asymmetry, whereas none of the control patients had marked asymmetry. All patients with marked asymmetry and approximately 70% of them with greater than maximum normal asymmetry had a comminuted fracture. CONCLUSIONS: The results of this study show that although the frequency of facial asymmetry in patients with ZMC fracture was higher than in the control patients, it was found in all patients to a certain extent. Patients' awareness of this fact can decrease their dissatisfaction.

Cone Beam Computed Tomographic Evaluation of Mandibular Asymmetry in Patients with Cleft Lip and Palate.

OBJECTIVE: The purpose of the present study was to compare mandibular vertical asymmetry in patients with unilateral and bilateral cleft lip and palate and subjects with normal occlusion. MATERIALS AND METHODS: Cone beam computed tomography scans of three groups consisting of 20 patients with unilateral cleft lip and palate, 20 patients affected by bilateral cleft lip and palate, and a control group of 20 subjects with normal occlusion were analyzed for this study. Condylar, ramal, and condylar plus ramal asymmetry indices were measured for all subjects using the method of Habets et al. Kruskal-Wallis and Mann-Whitney tests were used to determine any significant differences between the groups for all indices at the 95% level of confidence. RESULTS: There were no significant differences regarding sex for all mandibular asymmetry indices in all three groups. All Asymmetry indices (condylar, ramal, and condylar plus ramal asymmetry) were significantly higher in the unilateral cleft group compared with the other two groups. CONCLUSION: Cone beam computed tomography images showed that patients with cleft lip and palate suffered from mandibular asymmetry. Subjects with unilateral cleft lip and palate had a more asymmetric mandible compared with the bilateral cleft lip and palate and control groups. Therefore, the mandible appears to be the leading factor in facial asymmetry in subjects with unilateral cleft lip and palate.

Evaluation of the Course of the Inferior Alveolar Canal: The First CBCT Study in an Iranian Population.

BACKROUND: The frequent anatomical variations of the inferior alveolar nerve (IAN) course should be considered prior to any treatment in this area. The aim of this study was to evaluate the course of the inferior alveolar canal (IAC) as it appears in the archived CBCT images of the mandible. MATERIAL/METHOD: This cross- sectional study evaluated a sample of 156 CBCT examinations. The pattern of the IAC was evaluated and the prevalence of different patterns according to age and gender were recorded. In order to find the frequency of mandibular canal type among different ages, the patients were put into the three age groups (20-29, 30-44 and 45-59).The data were analyzed using Chi-square test and the significance level was set as p≤.05. RESULTS: Out of 156 patients, 52 canals was straight type, 52 had Catenary type and 52 of them were presented with Progressive descending type. There was not statistically significant difference between two genders (Pv=0.092). According to the type of the IAC course, there was a not statistically significant difference between the three age groups (Pv=0.32). CONCLUSIONS: Cone beam computed tomography is a useful method for precise assessment of the IAC course.

Evaluation of Extension Type of Canalis Sinuosus in the Maxillary Anterior Region: a CBCT Study.

OBJECTIVE: To evaluate the extension of canalis sinuosus (CS) into the alveolar crest for surgical reference in the anterior maxilla. METHODS: In this cross-sectional study, 485 CBCT images were evaluated in three orthogonal planes (axial, coronal and sagittal). The type of extension of CS into the alveolar ridge in the anterior maxilla was evaluated. The alveolar ridge was divided into four equal parts in a vertical and horizontal direction. In a vertical direction from apical to incisal and in a horizontal direction from labial to palatal, the four parts were designated as types 0, I, II and III, respectively. The extension of CS into the alveolar ridge was then traced. RESULTS: CS was present in 380 subjects (78.35%), and the extension type was unilateral in 217 of them (57.11%) and bilateral in 163 of them (42.89%). There was no significant relationship between incidence of CS and sex. Regarding the distribution of vertical and horizontal types, type II (the third quadrant of the ridge from apical to incisal and from labial to palatal, respectively) was significantly more prevalent than other types. CONCLUSION: The most common location of CS into the alveolar ridge in both horizontal and vertical directions was type II (which is not close to the cortex). Awareness about the presence and possible locations of CS helps to reduce the risk of unjustifiable postoperative complications.

Association between Condylar Bone Changes and Eichner Index in Patients with Temporomandibular Dysfunction: A Cone Beam Computed Tomography Study.

Statement of the Problem: Eichner index is a dental index, which is based on the occlusal contacts between naturally existing teeth in premolar and molar regions. One controversial topic is the association between occlusal status and temporomandibular joint dysfunction (TMD) and its associated degenerative bony changes. Purpose: Through the use of cone-beam computer tomography (CBCT), the current study sought to ascertain the relationship between the Eichner index and condylar bone alterations in TMD patients. Materials and Method: In this retrospective study, the CBCT images of bilateral temporomandibular joints (TMJs) of 107 patients with TMD were evaluated. The patients' dentition was classified into three groups of A (71%), B (18.7%), and C (10.3%), according to the Eichner index. Radiographic indicators of condylar bone alterations, including as flattening, erosion, osteophytes, marginal sclerosis, subchondral sclerosis, and joint mice, were either present or absent and registered as 1 or 0, respectively. Chi-square test was used to evaluate the link between the condylar bony changes and the Eichner groups. Results: According to the Eichner index, the most prevalent group was group "A". The most prevalent radiographic finding was "flattening of the condyles" (58%). Condylar bony changes were found to be statistically related to age (p= 0.00). However, no significant relationship was found between sex and condylar bony changes (p= 0.80). There was a significant relationship between the Eichner index and condylar bony changes (p= 0.05). Conclusion: Patients with greater loss of tooth supporting zones have more condylar bony changes.

Are of Osteomeatal Complex Variations Related to Nasolacrimal Canal Morphometry.

INTRODUCTION: Due to the close anatomic relationship between paranasal structures and NLC, the morphometric measure of the nasolacrimal canal (NLC) could be affected by the osteomeatal complex (OMC) anatomical variations. The present study aimed to assess the effect of OMC variations on the NLC morphometric features using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This cross-sectional study consisted of CBCT images of 150 subjects in the case group with at least one OMC variation and 40 cases in the control group without any OMC variation within the age range of 18-50 years. The presence of the OMC variations, including agger nasi, nasal septum deviation, concha bullosa, Haller cells, paradoxical middle turbinate, and pneumatization of the uncinate process, was evaluated in each patient. The NLC morphometric measurements were performed and compared between the case and control groups. RESULTS: The middle anteroposterior diameter and middle sectional area of NCL were significantly higher in patients with OMC variations, as compared to that in the control group. The NLC volume was significantly higher in patients with agger nasi, nasal septum deviation, concha bullosa, and pneumatization of the uncinate process, as compared to that in the control group. Nonetheless, no significant difference in NLC angulation with the nasal floor or Frankfurt horizontal plane was observed in the presence of each OMC variation. CONCLUSIONS: As evidenced by the obtained results, a higher volume of the canal was revealed in the presence of some of the OMC variations. Therefore, it can be suggested that OMC variations cannot be a predisposing factor in cases with primary acquired nasolacrimal duct obstruction.

Symphysis morphology and mandibular alveolar bone thickness in patients with ß-thalassemia major and different growth patterns.

OBJECTIVE: The present study aimed to assess the morphology of symphysis and alveolar bone thickness (ABT) surrounding mandibular incisors in thalassemic patients, as compared to unaffected individuals. METHODS: This case-control study was conducted on lateral cephalograms of 60 thalassemic and 60 unaffected patients with Class II malocclusion seeking orthodontic treatment at Dental School, Shiraz University of Medical Sciences. The sample was divided into three subgroups including hyperdivergent, normodivergent, and hypodivergent, according to the Jarabak index. Symphysis dimensions and alveolar bone thickness surrounding mandibular incisors were measured using AutoCad software. Finally, the correlation between alveolar bone thickness and symphysis morphology was assessed. RESULTS: In general, chin dimensions and bone thickness at different levels of mandibular incisor roots (cervical, middle, apical) were smaller in thalassemic adolescents than controls. Concerning the total sample as well as the normodivergent subgroup, significantly lower values were observed in thalassemic patients for symphysis width, total ABT at the cervical, and lingual ABT at the apical root area compared to controls (p < 0.05). The hypodivergent growth pattern was not associated with any statistical differences between the groups (p> 0.05). In both thalassemic and control subjects, symphysis width showed a weak to moderate positive correlation with ABT of lower incisors (p< 0.05), whereas symphysis height showed a moderate positive correlation with cervical ABT in only ß-thalassemia patients (p< 0.05). CONCLUSIONS: Compared to controls, ß-thalassemia patients showed thinner alveolar bone at different levels of lower incisor roots and smaller symphysis dimensions. There were significant correlations between symphysis dimensions and alveolar bone thickness of mandibular incisors in the sample.

Assessing the efficacy of a modified crushing technique for the management of concha bullosa: a cone beam computer tomography study.

INTRODUCTION: Although many surgical techniques exist to manage obstructive concha bullosa, there continues to be a drive to find the least invasive technique with the fewest complications and best results. OBJECTIVES: The purpose of this study is to describe and assess the short- and long-term efficacy of a modified crushing technique for concha bullosa management. METHODS: Patients who met inclusion criteria underwent a detailed nasal examination and cone beam computed tomography imaging prior to and after septoplasty with crushing surgery for obstructive concha bullosa. Patients were divided into short- and long-term groups based on their followup period such that the short-term group had a mean followup of 15.14 months (range 6-22 months) and the long-term group had a mean followup of 56.66 (range 29-80) months. RESULTS: Twenty-four cases of obstructive concha bullosa were included in this study with 13 short-term and 11 long-term follow-ups. All patients showed a significantly decreased postoperative CB size (p < 0.001). There was no correlation between age and postoperative CB change in area (p = 0.39) and no significant difference in the amount of postoperative CB area reduction between the short-term and long-term groups (p = 0.35). No patients experienced bleeding, synechia, conchal destruction, or olfactory dysfunction on followup evaluations. CONCLUSIONS: Our modified crushing technique is a simple, effective, and lasting treatment option for concha bullosa. From our experience, there have been no complications and no instances of concha bullosa reformation during the follow-up period.

Evaluation of the association between osteoporosis and periodontitis in postmenopausal women: A clinical and radiographic study.

Background: This study aimed to assess the relationship between the osteoporotic condition and periodontitis in postmenopausal women. Materials and Methods: Ninety-four women aged 50-80 years were studied in this cross-sectional study. Bone mineral density (BMD) of lumbar vertebra BMD (LBMD), total hip BMD (HBMD), and neck of femur BMD (NBMD) was assessed using standardized dual-energy X-ray absorptiometry (DXA) (normal: T-score ≥-1, osteopenic: -2.5 ≤ t-score <-1, osteoporotic: T-score <-2.5). Bleeding point index (BI), O'Leary plaque index (PI), and clinical attachment loss (CAL) were recorded. Cementoenamel junction, alveolar-crest distance (CEJ-AC) was measured from cone-beam computed tomography images. Periodontitis severity was represented by CAL and CEJ-AC distance. One-way analysis of variance followed by Post hoc Tukey was performed for examining differences among the groups for different variables. Pearson correlation coefficient® and backward regression analysis were used to investigate the effect of confounding variables on CEJ-AC as the dependent variable. Significance was considered at P < 0.05. Results: Mean CEJ-AC was significantly higher in the osteoporotic and osteopenic groups compared to the normal group (P = 0.001). There was a significant positive correlation between CEJ-AC and NBMD and LBMD (P < 0.001). The associations between LBMD and CEJ-AC existed even after adjusting for confounding factors (P = 0.002). The differences in BI, PI, and CAL were not statistically different between the groups (P > 0.05). Conclusion: Although osteoporosis is not the main cause of periodontitis, it can indirectly affect periodontal status by increasing CEJ-AC. Early diagnosis of osteoporosis followed by early referral to a dentist for the treatment of potential existing periodontal diseases is important to avoid complications among postmenopausal women.

Analysis of hard tissue facial symmetry after unilateral mandibular reconstruction.

BACKGROUND: This study aimed to determine how successful reconstruction of the mandible can recover the symmetry. MATERIALS AND METHODS: All patients who underwent surgical treatment for unilateral mandibular reconstruction in 4 years were retrospectively examined. Bilateral differences of gonion (GO) positions were measured in 3 dimensions based on immediate postoperative computed tomography. The data collected was analyzed in 3 ways: First, the comparison of bilateral differences of GO in 3 dimensions. Second, the mean Asymmetry Index in control subjects was used to divide all cases into three groups: "Symmetry," "Asymmetry," and "Marked asymmetry." Third, "maximum normal asymmetry" was calculated, and all cases were categorized as below and above maximum normal asymmetry. The difference between two gonial angles was used to determine the amount of asymmetry. RESULTS: Forty-seven patients and 47 normal adults were enrolled. The mean bilateral GO difference in the control group was higher than in the study group patients, but it was not statistically significant. The mean Asymmetry Index for the control group was not also significantly higher than the study cases. The study group was "Symmetric" in 78.7% of the cases whereas the control group in 91.4%, 19.1% of the study group and 8.5% of controls were "Asymmetric," and 2.1% of study cases and 0% of controls were "Markedly Asymmetric." Maximum normal asymmetry was 82.9% in the study group and 97.8% in the control group. The mean differences between the right and left gonial angles were higher in the study group, but it was not significant (P = 0.1). CONCLUSIONS: Our study's results showed that bilateral symmetry in mandibular reconstruction patients was satisfactory and similar to the normal individuals.

Assessment of mandibular characteristics in patients affected with ß-thalassaemia major: A retrospective case-control study.

OBJECTIVE: Thalassemia is the most common hereditary blood disorder across the world. This study aimed to identify some mandibular features of thalassaemic patients and compare them with unaffected counterparts. MATERIAL AND METHODS: This retrospective case-control study was carried out on lateral cephalograms of 60 subjects (26 males, 34 females) with class II malocclusion and age range of 11 to 15 years. The control group consisted of 60 non-thalassaemic subjects with class II malocclusion and similar chronological age, gender and vertical facial dimension. Based on the Jarabak index, the case and control subjects were classified into hyperdivergent, normodivergent and hypodivergent growth patterns. Four linear (ramus height, ramus width, mandibular depth, and antegonial notch depth) and 3 angular (symphyseal angle, gonial angle, and mandibular arc angle) cephalometric parameters were measured to represent mandibular morphology. The data were analysed using Chi-square test and Student's t-test. RESULTS: No significant difference was found in linear measurements between thalassaemic patients and controls. The symphysis angle was significantly greater and the mandibular arc angle was significantly smaller in the total thalassaemic sample than the control individuals (P<0.001 and P=0.004, respectively). The difference in symphysis angle was significant in both hyperdivergent and normodivergent subjects (P=0.004 and P=0.002, respectively), whereas the difference in mandibular arc angle was only significant in the normodivergent subgroup P=0.001). CONCLUSIONS: The smaller mandibular arc angle in the thalassaemic sample suggests a more superior than posterior growth direction of condyles compared with healthy individuals. The difference in symphyseal angle represents inherent differences in chin morphology between thalassaemic subjects and controls.

Comparison between Glenoid Fossa Roof Thickness in TMD and non-TMD Patients, a CBCT Study.

STATEMENT OF THE PROBLEM: Various pathologic conditions can affect the thickness of the roof of glenoid fossa (RGF). The relationship between the RGF thickness and temporomandibular joint disorder (TMD) is not explicitly investigated. Considering the changes in RGF thickness, as a radiographic sign for TMD diagnosis, the phenomenon may necessitate specific treatment and may influence the treatment course and results. PURPOSE: This research was designed to examine the relationship between TMD and RGF thickness changes compared to non-TMD group. MATERIALS AND METHOD: In this cross sectional analytic research CBCT images of 70 TMD patients (140 joints) and 70 non-TMD individuals (140 joints) as control group were evaluated for thickness of RGF and presence of discontinuity in RGF. The distance between superior and inferior cortex of glenoid fossa was measured as RGF thickness. Inability to follow the course of cortex in any given image was considered as discontinuity. T-test, Chi-square and odds ratio (OR) were used for statistical analysis. In this study, p< 0.05 was considered meaningful. RESULTS: The mean thickness of RGF in our non-TMD samples was 1.12 mm. RGF thickness was significantly increased in TMD patients compared non-TMD group (p= 0.00). This value was also greater in males. On the other hand, TMD patient showed a higher incidence of discontinuity in RGF, in comparison with non-TMD patients (p= 0.006). CONCLUSION: The increased thickness of RGF can be considered as a sign of TMD, which may help in diagnosis of TMD. It seems that there is a direct relationship between TMD and discontinuity of RGF.