Search

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 ± 14.6. 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° ± 3.5°. 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.

BackgroundThe 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.MethodsCBCT 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).Results413 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.ConclusionsIn 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.

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.

Background: Considering the late ossification potential of spheno-occipital synchondrosis (SOS), it can be used as a tool to estimate age in adolescents. The time of SOS fusion is known to vary in different populations. Objectives: This study aimed to assess the degree of SOS fusion in Iranian individuals, using cone-beam computed tomography (CBCT) scan. Patients and Methods: The CBCT images of 240 patients (126 females and 114 males), aged 6 - 25 years, were assessed regarding the degree of SOS fusion, based on a four-stage scoring system. Spearman’s correlation coefficient test and regression analysis were performed to assess the correlation between age and fusion stage. Mann-Whitney test was also applied to determine differences between males and females. Besides, Kruskal-Wallis test was used to assess differences in the median values. Results: The SOS was completely open at the mean age of 7.63 years in females and 8.85 years in males. The mean age of partially fused SOS (stage 1) was 8 years in females and 10 years in males. Besides, the mean age of completely fused SOS (stage 3) was 12 years in females and 16 years in males. The results of Spearman’s correlation coefficient test showed a significant positive relationship between age and the degree of SOS fusion in males and females (rs = 0.783, P < 0.001 in females and rs = 0.911, P < 0.001 in males). Conclusion: The SOS closure degree can be applied for age estimation in the Iranian population. This study presented a method which is highly accurate for age estimation.

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.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.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 (P0.001 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).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.

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.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.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.The first molar tooth showed an acceptable level of sex determination accuracy based on the odontometric measurements.

BackgroundThis study aimed to determine how successful reconstruction of the mandible can recover the symmetry.Materials and methodsAll 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.ResultsForty-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).ConclusionsOur study’s results showed that bilateral symmetry in mandibular reconstruction patients was satisfactory and similar to the normal individuals.

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).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.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.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.

Background: Injuries to the lingual and inferior alveolar nerves (IAN) through third molar surgery are common and complicated clinical problems. Juxta-apical radiolucency (JAR) is one of the new radiographic signs, suggestive of IAN damage. Objectives: This study aimed to assess the relationship between JAR and IAN and to determine its effects on the cortical plate. Methods: In this cross-sectional study, after evaluating an initial sample of 450 cases, the cone-beam computed tomography (CBCT) images of 20 patients with JAR were compared with those of 20 age-matched patients without JAR in the axial and multi-planar images. The relationship between JAR and IAN was evaluated, and thinning of the mandibular cortical plates was also investigated. Statistical analysis was performed using descriptive tests and chi-square test in SPSS version 23. Results: The relationship between JAR and IAN was statistically significant (P = 0.001). The cortical plates were perforated in 75% of cases with JAR as opposed to 45% of cases without JAR (P = 0.06). The relationship between the location of JAR and IAN was also significant (P = 0.004). Conclusions: Based on the present results, JAR was associated with IAN in most cases. Thinning of the cortical plates was observed in all cases of JAR.

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. Conclusion: 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.

We aimed to study the prevalence of orbital blowout fractures and evaluate the causes and the location of orbital cavity fractures. In this cross-sectional study, the medical records of all patients admitted with facial trauma were assessed, sociodemographic information as well as the aetiology of trauma extracted, and the computed tomographic images of the patients were reassessed. Location of orbital blowout fractures and the severity of orbital fractures were evaluated. A total of 203 cases had blowout fractures (175 male and 28 female patients with a mean (SD) age of 36 (16) years. Road traffic accidents (n=139, 69%) were the most common cause of orbital blowout fractures. Falls (n=29, 14%) and assault (n=20, 10%) were the other causes of trauma to the orbital structure, which resulted in blowout fractures. The medial wall was the most commonly involved location (n=81, 40%) followed by orbital floor (n=64, 32%), the combination of medial wall and floor (n=36, 18%), medial wall and maxilloethmoidal strut combination (n=13, 6%), and all the three locations altogether (n=9, 4%). Most of the blow-out fractures had mild severity (n=107, 53%). There was a significant relation between the severity and location of the blowout fractures (p

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.

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.

PURPOSE: The temporal bone represents a variety of pneumatization patterns with clinical significance for planning surgical procedures in this area. The purpose of the present study was to assess the prevalence and characteristics of the glenoid fossa and articular eminence pneumatization and to classify the pattern of pneumatization using CBCT images. METHODS: CBCT images of 327 patients (654 temporal bones) were evaluated to determine pneumatized articular eminence prevalence and characteristics. Gender, age, laterality, type and grade of pneumatization were recorded for the left and right sides. Chi-square test was used to evaluate the relationship between pneumatized articular tubercle and gender, grade and type. RESULTS: PAT was identified in 251 (76.7%) patients of whom 139 (55.4%) were male and 112 (44.6%) were female with a mean age of 30.31 ± 10.32 years. Bilateral PAT occurred in 175 (69.7%) patients. Three hundred and ninety-six (93%) of areas were multilacunar, and 30 (7%) were unilacunar. Of 654 areas, 228 (34.8%) had grade 0, 299 (45.7%), grade 1, 92 (14.1%), grade 2 and 35 (5.4%), grade 3. No statistically significant correlation was found between prevalence of pneumatization, gender, type and grade. CONCLUSION: The present study emphasized the need to assess PAT before surgical intervention of TMJ. CBCT provides reliable and accurate information to determine the characteristics, the exact extension of pneumatization and its relationship to the adjacent structures. The preoperative temporal bone CBCT is a crucial component of the evaluation of PAT in patients candidate for surgical intervention of TMJ.

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.

Introduction: Temporomandibular disorders (TMDs) are the main source of orofacial pain of nondental origin. Density changes in mandibular condyles of patients with TMD have not been well documented. The aim of this study was to compare condylar head bone density values in patient with and without TMD in cone-beam computed tomographic (CBCT) images. Materials and Methods: CBCT images of 70 patients with TMD and 70 age- and sex-controlled individuals were studied. Density of the cancellous bone in the left and right condylar heads was measured on a CBCT slice with the widest mediolateral dimension. Moreover, absence of at least one maxillary or mandibular posterior tooth (except for third molars) was recorded. Interclass correlation, t test, and Chi-squared test were used for statistical analysis. Results: Bone density in the condylar head significantly increased in patients with TMD compared with the non-TMD group (P < 0.001). The difference between males and females in each group was not significant (P = 0.182). Condylar head bone density in patients with TMD with posterior missing teeth was significantly less than individuals without missing teeth (P = 0.002). Conclusion: Increased density of condylar head must be regarded as a potential diagnostic tool for TMD when interpreting CBCT images of the joints.

BACKGROUND: 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 AND METHODS: 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.

Context: Better understanding of the anatomical location and course of the mandibular canal is necessary to avoid damaging inferior alveolar nerve. Aims: The aim of this study was to investigate the buccolingual course of the inferior alveolar canal (IAC) in different mental foramen locations, using cone beam computed tomography. Materials and Methods: Three hundred and twelve hemimandibular images were evaluated in this study. The location of mental foramen in relation to the apices of mandibular premolar and molar teeth were recorded. Nine measurements (in millimeters) were taken at the level of the IAC and posterior mandibular premolar and molar root apices. Relative distances of IAC to buccal and lingual mandibular cortex were calculated for different mental foramen types. Statistical Analysis Used: Data were analyzed by one-way analysis of variance and P < 0.05 was considered to be statistically significant. Results: The distribution of subjects according to the type of mental foramen includes: Type 1 = 50.3% (at the level of second premolar apex), Type 2 = 33% (between the apices of first and second premolars), and Type 3 = 16.7% (between the apices of second premolars and first molars). The buccolingual ratio of the IAC position was statistically significant in different mental foramen types (P = 0.00). Conclusion: The position of IAC was affected by the location of the mental foramen. The direction of IAC gradually changed from lingual to buccal and from posterior to anterior.

Purpose Temporomandibular disorder (TMD) is a common problem in modern societies. Causes of TMD, as a consequence of condylar asymmetry index (CAI), are still a subject of controversy. The aim of the present study was to determine the possible correlations between the degree of condylar asymmetry and clinical dysfunction indices. Materials and methods In this cross-sectional study, we used the Habets method to measure the CAI in 42 TMD patients. The participants' age and sex were matched in the control group. Patients were divided into mild, moderate and severe dysfunction groups based on Helkimo's clinical Di. The data were analyzed using Mann–Whitney U and Kruskal–Wallis tests. Also, the study attempted to assess the possibility of correlation between age and CAI. Results The CAI values of TMD patients were significantly higher than those of the control group (P = 0.001). However, CAI was not significantly different among TMD patients with different dysfunction index. There was no significant correlation between CAI and age (Spearman r = 0.655, P = 0.23). Conclusion Based on the findings of the present study, patients with condylar asymmetry index are more susceptible to TMD. However, degree of the condylar asymmetry is not a criterion for TMD signs and symptoms.

The uvuloglossopharyngeal dimensions (UGPDs) are assumed to be affected by thalassemia major (TM). Because thalassemia intermedia (TI) is a milder form without need for blood transfusions, this study aimed to evaluate whether the UGPDs in thalassemic patients are equally affected by the two forms. The study sample comprised 52 lateral cephalograms from thalassemic patients (31 TM; 21 TI) aged 12.98 ± 1.66 years. The control group comprised 25 lateral cephalograms from non-thalassemic subjects aged 13.64 ± 1.55 years with ANB > 3°. Linear measurements including tongue length (TGL), tongue height (TGH), soft palate length, uvula thickness (UT), superior airway space, middle airway space, inferior airway space, and mandibular plane to hyoid (MP–H) were recorded using AutoCAD 2007 software. Mean TGL, TGH, and MP–H in the thalassemic patient group were significantly smaller than those in the control group (all P

Background : As the basic biological relationship of form and function, changes in the normal pattern of nasopharyngeal space can profoundly affect the development of the craniofacial growth. The lateral cephalogram, part of the patient’s normal records for orthodontic treatment, may show some of these changes either at the initial examination or later during treatment. The validity of the information the lateral cephalogram may present, have been questioned previously. The aim of this study was to assess correlation between the area and the volume measurements of pharyngeal airway size in a lateral cephalogram and a 3-dimensional (3D) cone-beam computed tomography (CBCT) scan in adolescent subjects. Materials and Methods : CBCT scan and a lateral cephalogram of 35 subjects which were taken within 1 week were included in this study. Airway area of the region of interest from the lateral cephalogram and airway volume over the same of region of interest from the CBCT scan were assessed for all patients. The correlation between the area and the volume measurements were evaluated statistically by Pearson’s correlation coefficient test. Mann Whitney U Test was used for comparing the area and the volume measurements in different sex. Results : Strong correlation was found between lateral cephalogram and CBCT measurements of pharyngeal airway. (r=0.831). Conclusion : Pharyngeal airway area on a lateral cephalogram is correlated strongly with volumetric data on CBCT images. Henceforth the use of CBCT images for volume measurements in orthodontic patients can aid in the better evaluation of airways and acted as a diagnostic instrument in this area.

Corresponding Author: Leila Khojastepour Address: No. 232, between Molasadra and Felestin Avenue, Moadel Avenue, Shiraz,Iran Telephone: +989173158331 E-mail: khojastl@sums.ac.ir 1Assistant Professor, Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Shiraz University of Medial Science, Shiraz, Iran 2 Dental Practitioner The study aimed to compare the accuracy of proximal caries detection by dental practitioners using two different systems, direct digital system and conventional films, under routine environmental conditions. Materials and methods: Eleven extracted human posterior teeth were mounted on wax frames and were exposed using the direct digital system and conventional films. Seventy-four dental practitioners evaluated these images for proximal caries. No environmental conditions were dictated. The dental practitioners’ evaluations were compared with histopathological sections that were used as the gold standard. Results: There were no statistically significant differences in the dental practitioners’ ability to detect caries using the direct digital and conventional systems (P=0.548).No significant differences were found between groups based on the level of the dental practitioners’ work experience (P=0.167). Conclusion: Dental practitioners work well with both direct digital and conventional systems in the diagnosis of proximal caries, although the routine environmental condition is not the ideal one. Further, this ability is so basic that it is not influenced by the level of the dental practitioner’s experience. Therefore, we recommend that digital systems be considered for use in dental offices.

Background:Several anatomical variations can lead to the inflammation of the paranasal sinuses; therefore, surgeons should be familiar with these variations and their impacts on the status of the paranasal sinuses.Objectives:The present study aimed to determine the prevalence of Haller cells and its association with patients’ sex and age. Furthermore, the relationships between the presence and size of Haller cells, deviation of the uncinate process and size of the maxillary sinus ostium with the occurrence of maxillary sinusitis were investigated.Materials/ Patients and Methods:120 coronal CBCT images were retrieved and analyzed. Statistical analysis of the data was performed by means of Mann - Whitney, χ2and T tests.Results:There were statistically significant associations between the presence and surface area of Haller cells and the occurrence of ipsilateral maxillary sinusitis. Neither the angulation of the uncinate process nor the size of the maxillary sinus ostium significantly correlates with the formation of maxillary sinusitis.Conclusion:Haller cells can interfere with the normal drainage of the maxillary sinus and result in sinusitis. In contrast, diameter of the sinus ostium and deviation of the uncinate process do not influence the inflammatory status of the maxillary sinus significantly.

Background. Usefulness of ultrasound (US) in detection of intrabony lesions has been showed. A cortical bone perforation or a very thin and intact cortical bone is prerequisite for this purpose.Objective. The current in vitro study was aimed at measuring the cut-off thickness of the overlying cortical bone which allows ultrasonic assessment of bony defects.Materials and Methods. 20 bovine scapula blocks were obtained. Samples were numbered from 1 to 20. In each sample, 5 artificial lesions were made. The lesions were made in order to increase the overlying bone thickness, from 0.1 mm in the first sample to 2 mm in the last one (with 0.1 mm interval). After that, the samples underwent ultrasound examinations by two practicing radiologists.Results. All five lesions in samples numbered 1 to 11 were detected as hypoechoic area. Cortical bone thickness more than 1.1 mm resulted in a failure in the detection of central lesions.Conclusion. We can conclude that neither bony perforation nor very thin cortical bones are needed to consider US to be an effective imaging technique in the evaluation of bony lesion.

Statement of the Problem Anatomic variation can potentially impact the surgical safety. Purpose The purpose of this cross-sectional study was to assess the prevalence of ostiomeatal complex variations based on cone beam computed tomography (CBCT) images of the patients seeking rhinoplasty. Materials and Method In this cross-sectional study, CBCT images of 281 patients including 153 female and 128 male with Mean±SD age of 26.97±7.38 were retrieved and analyzed for presence of variations of ostiomeatal complex and mucosal thickening. All CBCT images were acquired by NewTom VGi scanner with 15×15 field of view, as a part of preoperative recording of patients seeking rhinoplasty in an otolaryngology clinic. Chi- square test and Odds ratio were used for statistical analysis of the obtained data and p< 0.05 was considered to be statistically significant. Results Agger nasi cells which were seen in 93.2% of the cases were the most common anatomic variation. It was followed by Haller cells (68%), concha bullosa (67.3%), uncinate process variations (54.8%), nasal sepal deviation (49.5%) and paradoxical curvature of middle turbinate (10%). Mucosal thickening were detected in 60.7% of the studied cases. Conclusion Ostiomeatal complex variations and mucosal thickening are considerably prevalent among the patients seeking rhinoplasty. This study also revealed that CBCT evaluation of paranasal sinuses has comparable result in delineation of the sinonasal anatomy.

Introduction Internal root resorption lesions may perforate external root surfaces, which may not be detectable on conventional radiographic images. The purpose of this study was to evaluate the accuracy of cone-beam computed tomographic (CBCT) imaging in the detection of small perforations within simulated internal resorption cavities. Methods Artificial internal root resorption cavities with minimal (0.1–0.2 mm) wall thickness were prepared at 64 sites on buccal and lingual halves of 32 single-rooted mandibular teeth that had been split mesiodistally. Perforations with 0.5-mm diameters were produced using a #40 K-file in half of the specimens. All teeth were placed in dry sheep mandibles and imaged using a NewTomVGi CBCT scanner (6 × 6 cm field of view, 0.1-mm resolution; NewTomQR srl, Verona, Italy). Two observers evaluated the images. Interexaminer and intraexaminer agreement were assessed using the kappa statistic. Sensitivity, specificity, and predictive values were used to assess diagnostic accuracy. Results Intra- and interobserver agreement on perforation detection were high. The sensitivity and specificity of CBCT-based detection of perforation in internal root resorption were 81.3% and 84.4%, respectively. Conclusions CBCT imaging is useful for perforation detection in internal root resorption defects.