Statement of Problem: Nasopharyngeal obstruction by adenoid enlargement is one of the main causes of mouth breathing. Diagnostic indices of nasopharyngeal obstruction by lateral cephalometric radiography are controversial. Purpose: The purpose of this study was to diagnose the nasopharyngeal obstruction by means of lateral cephalometric radiography. Materials and Methods: In this research two groups, (study and control), of 6 to15 years old were studied. In the study group, 46 mouth breathers were clinically examined by an orthodontist and an Otolaryngologist to confirm the nasopharyngeal obstruction. Control group was also comprised of 46 nasal breathers within the same age groups. A lateral cephalogram in centric occlusion was obtained for each patient. After tracing, following 7 nasopharyngeal variables were measured: 1- pp (palatopharyngeal depth). 2- Ad.Pmp (nasopharyngeal airway depth). 3- Air area (nasopharyngeal airway area). 4- NP area (bony area of nasopharynx). 5- Ba.Pmp (bony depth of nasopharynx). 6- d (bony depth of nasopharynx). 7- h (bony height of nasopharynx). Statistical t-test was conducted following calculating the mean, standard deviation and p-value of parameters. Discriminant function analysis was employed subsequent to the t-test for the significant variables, in order to find a method by which the values for several variables could be used simultaneously to determine whether obstruction exists. Qualitative variables of sex and age groups (6-10, 11-12, and 13-15 years old) were also used in discriminant analysis. Results: In the study group, mean value of pp, Ad.pmp, air area, Np area and Ba.pmp were significantly decreased, whereas mean of d and h variables were not considerably lessened. After performing analysis stage, the following discriminant function equation with critical point of 3.88 and correct classification of 94.57% was determined: D=0.345 (pp) +0.064 (Ad.pmp)-0.001(NP area) + 0.03(Air area) +0.505(Age1). If a person’s age is between 6 and 10 years old, we use one instead of Age 1 and if the age is between 11 and 15 years old, we consider zero in place of Age 1. Conclusion: If discriminant score is less than 3.88, the patient has nasopharyngeal obstruction with 94.57% probability.

Background and Aim: Due to the widespread use of lateral cephalometric radiography especially in orthodontic therapy and orthognathic surgery, obtaining radiographs of high quality with the least amount of radiation exposure is of utmost importance. The aim of this study was to compare the absorbed dose of head and neck target organs in conventional and digital lateral cephalometric radiography.Materials and Methods: In this experimental study, RANDO phantom was used for absorbed dose estimation in thyroid, parotid, pituitary and submandibular glands, bone marrow and ocular lens. The phantom was exposed 60 times: 30 times with CRANEX Tome, Soredex and 30 times with CRANEX D, Soredex with standard exposure settings. TLD (GR-200) dosimeters were used to measure organ doses. A total of 69 TLDs were used with 9 TLDs for background radiation. T -test was used for statistical analysis.Results: The mean absorbed dose of target organs was 0.04±0.005 mSv for conventional and 0.01±0.002 mSv for digital technique. The difference in absorbed dose in all target organs except for the thyroid gland (P=0.08) between the two techniques of conventional and digital was statistically significant. (P=0.01).Conclusion: Use of digital lateral cephalometric system causes a significant reduction in absorbed dose compared to the conventional film-screen system.

Introduction: The size and shape of sella turcica might be affected by pathological conditions.Clinicians should be familiar with the normal radiographic anatomy and morphologic variations of this area. The aim of this study was to evaluate the relationship between the shape and size of the sella turcica in subjects over 18 years of age with different skeletal malocclusions.Materials and Methods: In this descriptive-analytical study, at first pre-treatment lateral cephalograms of 246 patients (over 18 years of age) were divided equally into three groups of skeletal malocclusions of class I, II and III (82 patients in each group), with equal distribution of male and female subjects in each group. Then, the shape of sella turcica was determined according to standard references and its size was calculated using a software program. Data were analyzed with one-way ANOVA, chi-squared test and independent t-test using SPSS 18 (a = 0.05).Results: The majority of subjects (57.7%) had normal sella turcica shape. There were no significant differences in the shape (p value = 0.515) and size of sella turcica between the three skeletal malocclusions (p values of length, depth and diameter were 0.577, 0.881 and 0.575, respectively) and between genders (p values of shape, length, depth and diameter were 0.274, 0.22, 0.113 and 0.694, respectively).Conclusion: Under the limitations of the present study, there was no relationship between the shape and size of sella turcica and different skeletal malocclusions and gender of subjects over 18 years of age.

Background: Malocclusion, as a worldwide issue, can cause a lot of problems for patients. Panoramic (PR) and lateral cephalometric (LCR) radiographs are both usually indicated for orthodontic treatments. The aim of this study was to analyze vertical and sagittal parameters of both jaws on PRs and to compare them on LCRs. Materials and Methods: In this cross sectional study, 61 samples from all patients referring to the Department of Orthodontics of Shiraz Dental School were selected by simple randomized sampling method, meeting specific inclusion and exclusion criteria. Correlations between variables on PRs and LCRs were assessed. Results: Vertical angular variables on PR such as H-line/Lower1-Lower6 and Condylar plane/Corpus line were related to some vertical variables on LCR including Anterior nasal spine (ANS) -Menton (Me), Orbitale-Me, ANS-Posterior nasal spine (PNS) /Gonion (Go) -Me, Frankfort Horizontal (FH) /ANS-PNS, Gonial angle, Go-Gnathion (Gn) /Sella-Nasion and FH/Occlusal plane (P˂0.05).Sagittal variables of maxilla on PR such as Pterygomaxillare (Pm) -Pm, Pm-Ht, Pm-Ht-Pm, and ANS-Pm were related to sagittal variables of maxilla on LCR including Maxillary length, Sella/Nasion/Point A, Point A/Nasion/Point B (P˂0.05). Conclusion: Our results revealed that PRs can provide information on vertical and sagittal dimensions of both jaws. This may help choosing a proper imaging protocol for the patients.

Background: This study aimed to compare the gonial angle and alveolar bone height changes between panoramic and lateral cephalometry radiographic images in class II malocclusion patients before and after orthodontic treatment. Methods: The obtained radiographic images were selected from among 120 class 2 malocclusion cases. The gonial angle and alveolar bone height were measured in the midline and molar regions of panoramic and lateral cephalometric radiographs using the software tools before and after the treatment of patients. Study data were analyzed by SPSS statistical software (version 21. 0), and a significance level was set to 0. 05 for all statistical tests. Results: Based on the results, no significant difference was found regarding the gonial angle before and after treatment on the right and left sides in panoramic radiography and the gonial angle changes before and after treatment in cephalometric radiography (P > 0. 05). However, the obtained results for posterior and anterior alveolar ridge height were significant in panoramic and cephalometric radiographs (P < 0. 05). Moreover, the comparison of the measured gonial angle values before treatment in panoramic and cephalometric radiography represented a significant level (P < 0. 05). Eventually, the statistical results suggested that the alveolar bone height differences between panoramic and cephalometry radiography were significantly different in both anterior and posterior regions after treatment (P < 0. 05). Conclusions: The findings indicated that only measurements obtained from the panoramic radiography were valid for the gonial angle. However, panoramic and cephalometry radiography procedures cannot be replaced for assessing the anterior and posterior alveolar bone height.

Background and purpose: Digital radiography has led to many improvements in radiology. Despite many advantages there are different ideas in determining anatomical landmarks which results in some errors in cephalometric analyses. The aim of this study was to determine the degree of identification differences of anatomical landmarks by conventional and digital lateral cephalometric techniques using manual tracing of human skulls.Material and Methods: This descriptive-analytical study was conducted in 17 cases of human skulls in which metal radiopaque markers were attached to 9 landmarks as follows: N, S, ANS, PNS, A, B, Pog, the most inferior point of lower mandibular border, and Go. Conventional and digital lateral cephalograms were obtained from each skull with and without markers. The two cephalograms without markers were traced for landmarks by three orthodontists. Any difference between these landmarks and those of cephalograms with markers, were recorded and analyzed by student t-test.Results: The level of differences in S point was not statistically significant along both x and y coordinates. The measurement differences for the ANS and PNS points obtained by both radiographic methods were significant along the x coordinate but not significant along the y coordinate. Also, the measurement differences for the most inferior point of lower mandibular border, A, B, and Go points along both x and y coordinates were observed to be statistically significant. The measurement difference obtained for the Pog point was significant along the y coordinate and non-significant along the x coordinate.Conclusion: The difference in landmark identification between the two digital and conventional lateral cephalometric techniques was statistically significant for some points on both dimensions, however, the difference was not clinically significant.

Schizophrenia is a sever psychological disorder. Because of intricacy and obscurity of the disease, various methods including cephalometry, have been suggested for its diagnosis. The diagnostic value of cephalometry is not well established. Therefore a case-control analytic study was performed to compare some cephalometric parameters (head form, face form and head circumference) between a sample of schizophrenic patients (n=196) and a normal control group (n=198). Two groups were matched in height, weight, sex, age and social level. The control group consisted of nonschizoprenic men and women with no family history of schizophrenia. Our results showed that there was no significant difference in face from between two groups. But the head circumference mean in case group was significantly less than that of the control group. Also hyperbrachiocephaly was more frequent in case group. Our results indicated that genetic factors may play a role in incidences of this differences. Also, these findings, might be used as a rough screening method.