Evaluation of Diagnostic Values of a Gender Discrimination Function, Based on Mandibular Dimorphic Parameters in Iranian Population

Abstract Objective: To evaluate mandibular dimorphic parameters for sex determination by using panoramic radiographs and comparing the results with another equation. Material and Methods: In this analytical-descriptive study, the mandible variables, including the ramus height, the coronoid height, the mental height, and the distance between the right and left condyle, were measured in 326 panoramic radiographs. The discriminant function of the statistical method has previously been used to evaluate the diagnostic value of sex. The level of significance was considered 0.05. Results: The detection function obtained was statistically significant in quantitative correlation (p<0.001) with 99% agreement. Moreover, good sensitivity (81.72%), specify (80.25%), and moderate to good predictive values (PPV: 62.29 and NPV:91.6) were found. Among the mandibular parameters, chin height, ramus height, coronoid height, and distance between two condyles showed the highest gender dimorphism. Conclusion: Chin height, and ramus height have the most quality in gender dimorphism. A unique gender discrimination function has been obtained from the results.

Comparison of Diagnostic Quality of Multidetector Computed Tomography and Cone-Beam Computed Tomography in High and Low Resolution Modes for Assessment of the Nasal Cavity.

Background: We aimed to compare the diagnostic quality of multidetector computed tomography (MDCT) and cone-beam computed tomography (CBCT) in high (HR) and low (LR) resolution modes for assessment of the nasal cavity and paranasal sinuses. Methods: This in vitro study was conducted on 5 dry human skulls by using a CBCT and a MDCT scanner in HR and LR modes to assess their diagnostic quality for 21 anatomical landmarks of the nose. The quality of images was evaluated by two oral and maxillofacial radiologists and a dentist using a four-point Likert scale of (I) poor, (II) decreased, (III) good, and (IV) excellent. Data were analyzed by STATA at 95% confidence interval. The Chi-square test was applied to compare the quality of visualization of landmarks based on the type of scanner. Results: The diagnostic quality of HR CBCT and CT for the majority of landmarks was higher than that of LR CBCT and CT (P<0.05). The diagnostic quality of HR CBCT for agger nasi cells (P=0.010), olfactory cleft (P=0.032), sphenoethmoidal recess (P=0.032), and nasolacrimal duct (P=0.014) and LR CBCT for the middle turbinate (P=0.046) and middle meatus (P=0.031) was significantly higher than that of MDCT. Conclusion: The diagnostic quality of HR CBCT and CT for the majority of the landmarks in the nasal cavity and paranasal sinuses was higher than that of LR CBCT and CT. For the majority of landmarks, the diagnostic quality of CBCT and CT was the same; while for some landmarks, the diagnostic quality of HR and LR CBCT was higher than HR and LR CT. In general, CBCT has high efficacy for evaluation of the paranasal sinuses and the nasal cavity, and provides diagnostic information comparable to those provided by CT, but with a much lower radiation dose.

Effect of photobiomodulation therapy with different wavelengths on bone mineral density in osteoporotic rats.

Osteoporosis is associated with severe pain, bone deformity, fracture, and bone loss. It is important to find strategies to prevent bone resorption and treat osteoporosis. This study sought to assess the effect of photobiomodulation therapy (PBMT) with different wavelengths on bone mineral density (BMD) in osteoporotic rats. This animal study evaluated 63 adult female rats. The rats underwent ovariectomy to induce osteoporosis. Ovariectomized rats were randomly divided into 9 groups of control (OC), treatment with zoledronic acid alone (0.02 mg/kg), and treatment with 660 nm, 810 nm, and 940 nm PBMT alone (3 times a week for 6 weeks, energy density of 4 J/cm2), and combined with zoledronic acid. The healthy control group (HC) only underwent sham surgery. The rats underwent cone-beam computed tomography (CBCT) 52 days after the first treatment session to measure their BMD according to the gray value (GV) of images. To assess the biomechanical properties of bone, the resected bones were subjected to 3-point bending test (3-PBT). The experimental groups had significant differences with the OC group regarding radiographic and biomechanical properties of bone (P < 0.05), indicating a healing course. No significant difference was noted between the experimental groups treated with different laser wavelengths and those treated with zoledronic acid (P > 0.05). In the condition of this study, it was found that PBMT at a constant energy density of 4 J/cm2 with 660-, 810-, and 940-nm wavelengths is effective for enhancement of bone mineral density and biomechanical properties. No significant difference was noted between different wavelengths of diode laser regarding radiographic and biomechanical properties of bone.

Prevalence of permanent numeric dental anomalies in panoramic radiography in an Iranian population

Aim: Dental number anomalies are a group of congenital developmental disorders divided into two groups supernumerary and missing teeth. This study was conducted to investigate the prevalence of numeric dental anomalies using panoramic images in patients referred to the Hamadan Dental Faculty. Methods: In this cross-sectional study, 2,197 panoramic radiographs of patients aged 6-49 years were evaluated. These anomalies are divided into two groups: 1) Supernumerary teeth, including Mesiodens, Distodens, and Peridens, and 2) Missing teeth, including Hypodontia, Oligodontia, and Anodontia. A Chi-square test was performed to assess the relationship between the anomalies. Data analysis was performed using SPSS 16, in which P-value < 0.05 was considered the statistical significance level. Results: Of 736 males (32.2%) and 1548 females (67.8%) in this study, 32 (4.3%) and 55 cases (3.8%) had supernumerary teeth, respectively. The prevalence of supernumerary teeth was 0.3%, 0.5%, and 0.6% in males and 0.2%, 1% and 1.2% in females for mesiodens, distodens, and peridens, respectively. Also, 243 males (10.6%) and 655 females (28.6%) had missing teeth anomalies. Hypodontia in the maxilla was the most common anomaly in both genders, while mesiodens was the least common. Conclusion: Hypodontia was the most common anomaly, followed by peridens; the least common anomaly was mesiodens. The prevalence of supernumerary teeth was greater in males, though the difference was not statistically significant. In comparison, females had a greater prevalence of missing teeth

Complementarity of surgical therapy, photobiomodulation, A-PRF and L-PRF for management of medication-related osteonecrosis of the jaw (MRONJ): an animal study.

BACKGROUND: This study aimed to evaluate the complementarity of surgical therapy, photobiomodulation (PBM), advanced platelet-rich fibrin (A-PRF), and Leukocyte and platelet-rich fibrin (L-PRF) for the management of medication-related osteonecrosis of the jaw (MRONJ). METHODS: Sixty rats underwent injection of zoledronate followed by left mandibular first and second molar extractions to induce MRONJ lesions. All rats were examined for the signs of MRONJ 8 weeks post-dental extraction. Forty-nine rats with positive signs of MRONJ were appointed to seven different groups as follows: control (Ctrl); surgery alone (Surg); surgery and PBM (Surg + PBM); surgery and A-PRF insertion (Surg + APRF); surgery and L-PRF insertion (Surg + LPRF); surgery, A-PRF insertion, and PBM (Surg + APRF + PBM); surgery, L-PRF insertion, and PBM (Surg + LPRF + PBM). Euthanasia was carried out 30 days after the last treatment session. The lesions' healing was evaluated clinically, histologically, and radiographically. Data were analyzed using STATA software version 14, and the statistical significance level was set at 5% for all cases. RESULTS: According to the present study, A-PRF and L-PRF treatment resulted in significant improvements in clinical, histological, and radiographical parameters compared to the Ctrl group (P < 0.05). The PBM also decreased wound dimensions and the number of empty lacunae compared to the Ctrl group (P < 0.05). Surg + APRF + PBM and Surg + LPRF + PBM were the only groups that presented a significantly higher mean number of osteocytes (P < 0.05). No significant differences were observed between A-PRF and L-PRF treatment groups (P > 0.05). CONCLUSIONS: Surgical resection followed by applying A-PRF or L-PRF reinforced by PBM showed optimal wound healing and bone regeneration in MRONJ lesions.

Magnetic resonance imaging study of incidental findings in the paranasal sinuses and ostiomeatal complex.

Purpose: This study aimed to assess incidental abnormal findings in the paranasal sinuses and anatomical variations of the ostiomeatal complex (OMC) on magnetic resonance imaging (MRI) scans. Materials and Methods: MRI scans of 616 patients (mean age, 44.0±19.4 years) were evaluated. Prior to obtaining the MRI scans, a checklist of patients' clinical symptoms was filled out after obtaining their consent. The Lund-Mackay classification was used to assess the paranasal sinuses and OMC. The prevalence of abnormal findings and their associations with patients' age, sex, and subjective symptoms were analyzed by the chi-square test, independent-sample t-test, and analysis of variance. The level of significance was set at 0.05. Results: Abnormal findings in the paranasal sinuses were detected in 32.0% of patients, with a significantly higher prevalence in males (P<0.05), but no significant association with age (P>0.05). Epithelial thickening and retention cyst were the most common abnormal findings in the paranasal sinuses. According to the Lund-Mackay classification, 93% of the study population had normal sinuses (score<4). Concha bullosa and paradoxical concha were detected in 15.3% and 3.4%, respectively, with no significant association with the presence of septal deviation or Lund-Mackay classification (P>0.05). Conclusion: Considering the relatively high prevalence of abnormal findings in the paranasal sinuses, it appears that clinical symptoms alone are not sufficient to diagnose sinusitis. A more accurate strategy would be to assess radiographic images of the paranasal sinuses and use a classification system. Sinusitis should be suspected in patients receiving a high score in this classification.

Upper Airway Changes Following Different Orthognathic Surgeries, Evaluated by Cone Beam Computed Tomography: A Systematic Review and Meta-analysis.

PURPOSE: This study sought to assess the upper airway changes following different orthognathic surgeries using cone-beam computed tomography. METHODS: An electronic search of the literature was conducted in major electronic databases including Medline (PubMed), Web of Science, Scopus, and Open Grey for articles published up to January 20, 2018. Human studies that evaluated the changes in the volume and minimum cross-sectional area of the upper airway or its subdivisions in patients who had undergone orthognathic surgery by use of cone-beam computed tomography were included. Manual search of the bibliographies of the included articles was also conducted. The included studies underwent risk of bias assessment. RESULTS: A total of 1330 articles were retrieved. After excluding the duplicates and irrelevant articles, 41 studies fulfilled the eligibility criteria for this systematic review; out of which, 30 entered the meta-analysis. The majority of studies had a medium risk of bias. Mandibular setback, and maxillary advancement + mandibular setback decreased the volume of the upper airway (-6042.87 mm3 and -1498.78 mm3, respectively) and all its subdivisions in long-term (>3 months), except for the nasopharynx, the volume of which increased following maxillary advancement + mandibular setback. Mandibular advancement and maxillomandibular advancement both increased the upper airway volume in long-term (7559.38 mm3 and 7967.06 mm3, respectively); however, only the changes after the former procedure were significant. The minimum cross-sectional area increased after maxillomandibular advancement (161.43 mm2), and decreased following maxillary advancement + mandibular setback (-23.79 mm2) in long-term. CONCLUSION: There is moderate evidence to suggest that mandibular advancement is the only orthognathic movement that provides a statistically significant change in long-term upper airway volume.

Anatomical characteristics of mandibular bone in skeletal class I, II and III patients by using cone beam computed tomography images in an iranian population / Características anatômicas do osso mandibular em pacientes Classe I, II e III esquelética usando imagens de Tomografia Computadorizada de Feixe Cônico: em uma População Iraniana

Objetive: This study aimed to compare the anatomical characteristics of the mandible in patients with skeletal class I, II and class III disorders using cone beam computed tomography (CBCT). Material and Methods: CBCT scans of patients between 17 to 40 years taken with NewTom 3G CBCT system with 12-inch field of view (FOV) were selected from the archive. Lateral cephalograms were obtained from CBCT scans of patients, and type of skeletal malocclusion was determined (Class I, II or III). All CBCT scans were evaluated in the sagittal, coronal and axial planes using the N.N.T viewer software. Results: The ramus height and distance from the mandibular foramen to the sigmoid notch in class II patients were significantly different from those in skeletal class I (P < 0.005). Distance from the mandibular canal to the anterior border of ramus in class III individuals was significantly different from that in skeletal class I individuals (P < .005). Conclusion: Length of the body of mandible in skeletal class I was significantly different from that in skeletal class II and III patients. Also, ramus height in skeletal class I was significantly different from that in skeletal class II patients. CBCT had high efficacy for accurate identification of anatomical landmarks. (AU)

Objetivo: Este estudo teve como objetivo comparar as características anatômicas da mandíbula em pacientes com desordem esquelética Classe I, II e III usando imagens de tomografia computadorizada de feixe cônico (TCFC). Material e Métodos: Foram selecionadas de arquivo, imagens de TCFC (Sistema NewTon 3G) com FOV (campo de visão) 12 polegadas e incluindo pacientes entre 17 a 40 anos. Cefalometrias laterais foram obtidas a partir das imagens de TCFC e o tipo de maloclusão esquelética foi determinada (Classe I, II ou III). Todas as imagens de TCFC foram avaliadas nos planos sagital, coronal e axial usando o software de visualização N.N.T. Resultados: A altura do ramo e distância do forame mandibular para a incisura da mandíbula em pacientes Classe II foi significativamente diferente daqueles Classe I esquelética (p< 0.005). A distância do canal mandibular até a borda anterior do ramo em indivíduos Classe III foi significativamente diferente daqueles indivíduos Classe I esquelética (p<0.005). Conclusão: O comprimento do corpo da mandíbula na Classe I esquelética foi diferente significativamente daqueles pacientes em Classe II e III esquelética. Além disso, a altura do ramo na Classe I esquelética foi significativamente diferente daqueles pacientes Classe II esquelética. A TCFC apresentou alta eficácia para a identificação precisa de marcos anatômicos. (AU)

Knowledge level of Iranian dental practitioners towards digital radiography and cone-beam computed tomography / Nível de conhecimento de dentistas Iranianos sobre Radiografia Digital e Tomografia Computadorizada de Feixe Cônico

Objective: TThis study aimed to assess the knowledge level of Iranian dental practitioners about digital radiography (DR) and cone-beam computed tomography (CBCT). Material and Methods: In this cross-sectional study, a researcher-designed questionnaire was administered among 180 general dentists and specialists. The questionnaire had three main domains of demographic information, fifteen questions about knowledge of DR (advantages, disadvantages, physical properties) and twenty six questions about knowledge of CBCT (indications, applications, advantages, route of knowledge acquisition). Data were analyzed using descriptive statistics, t-test and Pearson's correlation coefficient. Results: Of 180 participants, 76 (42.2%) were females. The minimum, maximum and mean± standard deviation scores obtained in DR were 4, 14, and 9.031 ± 1.85 and in CBCT were 0,26 and 18.56 ± 4.81, respectively. In the CBCT domain, the participants had maximum knowledge about "low radiation dose" (72.8%) and minimum knowledge about the "role of CBCT in determination of bone density" (45%). In DR domain, the participants had maximum knowledge about "no need for radiographic films" (75.6%) and minimum knowledge about "not requiring manual processing" (15.6%). Overall, participants had higher level of knowledge about CBCT than DR. An inverse correlation was noted between age and work experience with the number of correct answers. However, no significant difference was noted in the knowledge level of males and females regarding CBCT or DR (p = 0.233 and p = 0.227, respectively). Conclusions: further education seem imperative for dentists in this respect for more efficient diagnosis and treatment planning, minimize patient radiation dose and save time and cost. (AU)

Objetivos: Avaliar o nível de conhecimento de dentistas iranianos sobre radiografia digital (RD) e tomografia computadorizada de feixe cônico (TCFC). Materiais e métodos: Neste estudo transversal, um questionário, elaborado por pesquisadores, foi aplicado a 180 dentistas clínicos geral e especialistas. O questionário tinha três domínios principais de informação demográfica, quinze questões sobre conhecimento de RD (vantagens, desvantagens, propriedades físicas) e vinte e seis questões sobre conhecimento de CBCT (indicações, aplicações, vantagens, protocolo de aquisição). Os dados foram analisados por meio de estatística descritiva, teste t e coeficiente de correlação de Pearson. Resultados: Dos 180 participantes, 76 (42,2%) eram do sexo feminino. Os escores mínimo, máximo e média ± desvio padrão obtidos na RD foram 4, 14 e 9,031 ± 1,85 e na CBCT foram 0, 26 e 18,56 ± 4,81, respectivamente. No domínio CBCT, os participantes tinham conhecimento máximo sobre "baixa dose de radiação" (72,8%) e conhecimento mínimo sobre o "papel da CBCT na determinação da densidade óssea" (45%). No domínio RD, os participantes possuíam conhecimento máximo sobre "não há necessidade de filmes radiográficos" (75,6%) e conhecimento mínimo sobre "não requer processamento manual" (15,6%). No geral, os participantes tinham maior nível de conhecimento sobre CBCT do que RD. Foi observado correlação inversa entre idade e experiência de trabalho com o número de acertos. No entanto, nenhuma diferença significativa foi observada no nível de conhecimento de homens e mulheres sobre TCFC ou RD (p = 0,233 e p = 0,227 respectivamente). Conclusão: Parece imperativo para os dentistas iranianos, mais educação nesse aspecto para diagnóstico e planejamento de tratamento mais eficientes, minimizar a dose de radiação para paciente, economizar tempo e custos. (AU)

Sex determination by osteometric assessment of the mastoid process using Cone Beam Computed Tomography / Determinação do sexo em uma população Iraniana por avaliação osteométrica do processo mastóide em imagens de TCFC

Objective: Sex determination is one of the most important parameters to identify in forensic science. Because the mastoid process is the most resistant to damage due to its position in the skull base, it can be used for sex determination. The purpose of this study was to measure the dimensions and convexity and internal angles of the mastoid process to present a model of sex determination in Iranian population. Material and methods: This study was performed on three-dimensional images of 190 Cone Beam Computed Tomography (CBCT) of 105 women and 85 men. On each CBCT the distance between the porion and the mastoid (PM), mastoid length (ML), the distance between the mastoidale and the mastoid incision (M-I), the mastoid height (MH), the mastoid width (MW), intermastoidale distance (IMD) the lateral surfaces of the left and right mastoids (IMLSD) and the Mastoid medial convergence angle (MMCA) was measured on both the right and the left. The data were analyzed by descriptive statistics, t-test, and discriminant function analysis. Results: Significant differences were found for all variables except MMCA and MF in both sex. All measured variables except MW were greater for men than women. The discriminant model achieved a total accuracy of 93.7%. Among the measured factors IMD and IMSLD had the most influence on sex determination. Conclusion: Measuring the dimensions of the mastoid process is a very good method for sex determination with high accuracy of 90% (AU)

Objetivo: A determinação do sexo é um dos parâmetros mais importantes para identificação na ciência forense. Por ser o processo mastóide resistente a danos, devido a sua posição na base do crânio, este poderia ser usado na determinação do sexo. O objetivo deste estudo foi mensurar as dimensões, convexidade e ângulos internos do processo mastóide para apresentar um modelo de determinação do sexo em uma população Iraniana. Material e métodos: Este estudo foi realizado em 190 imagens de tomografia computadorizada de feixe cônico (TCFC), sendo 105 mulheres e 85 homens. Em cada TCFC foram realizadas medidas no processo mastóide em comprimento (ML), altura (MH), largura (MW) em ambos os lados direito e esquerdo, também foi medida a distância entre o Pórion e o processo mastóide (PM), distância até incisura mastoidea (M-I), distância entre as superfícies mediais (IMD) distância entre as superfícies laterais dos processos direito e esquerdo (IMLSD) e o ângulo de convergência medial (MMCA). Os dados foram analisados por estatística descritiva, teste t e análise de função discriminante. Resultados: Diferenças significativas foram encontradas para todas as variáveis, exceto MMCA e MF em ambos os sexos. Todas as variáveis medidas, exceto MW, foram maiores para os homens do que para as mulheres. O modelo de análise de função discriminante alcançou uma precisão total de 93,7%. Entre os fatores medidos, o IMD e o IMSLD tiveram a maior influência na determinação do sexo. Conclusão: Podemos concluir que as dimensões do processo mastóide constituem um método para determinação do sexo, em população Iraniana, com precisão de 90% (AU)

Position of the hyoid bone and its correlation with airway dimensions in different classes of skeletal malocclusion using cone-beam computed tomography.

PURPOSE: This study investigated the position of the hyoid bone and its relationship with airway dimensions in different skeletal malocclusion classes using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT scans of 180 participants were categorized based on the A point-nasion-B point angle into class I, class II, and class III malocclusions. Eight linear and 2 angular hyoid parameters (H-C3, H-EB, H-PNS, H-Me, H-X, H-Y, H-[C3-Me], C3-Me, H-S-Ba, and H-N-S) were measured. A 3-dimensional airway model was designed to measure the minimum cross-sectional area, volume, and total and upper airway length. The mean cross-sectional area, morphology, and location of the airway were also evaluated. Data were analyzed using analysis of variance and the Pearson correlation test, with P values <0.05 indicating statistical significance. RESULTS: The mean airway volume differed significantly among the malocclusion classes (P<0.05). The smallest and largest volumes were noted in class II (2107.8±844.7 mm3) and class III (2826.6±2505.3 mm3), respectively. The means of most hyoid parameters (C3-Me, C3-H, H-Eb, H-Me, H-S-Ba, H-N-S, and H-PNS) differed significantly among the malocclusion classes. In all classes, H-Eb was correlated with the minimum cross-sectional area and airway morphology, and H-PNS was correlated with total airway length. A significant correlation was also noted between H-Y and total airway length in class II and III malocclusions and between H-Y and upper airway length in class I malocclusions. CONCLUSION: The position of the hyoid bone was associated with airway dimensions and should be considered during orthognathic surgery due to the risk of airway obstruction.

Maxillary osteosarcoma: a case report and review of maxillary sinus space-occupying lesions / Osteossarcoma maxilar: um relato de caso e análise de lesões que ocupam o espaço do seio maxilar

Osteosarcoma is a relatively rare lesion in the maxillary bone. The proximity of the lesion to the maxillary sinus provides a null space with the minimum resistance to progress prior to manifest clinically, which makes the early diagnosis more critical. We report a case of maxillary osteosarcoma in a 21-year old male patient who was presented with the chief complaint of the pain and swelling on the left side of palate since 2 months earlier. A cone-beam computed tomography of the maxilla revealed a diffuse hyper-intense entity at the left side of the maxilla. Totally-occupied maxillary sinus space, asymmetric periodontal ligament widening of the involved teeth and spiculated and sunray periosteal reaction were recognized. The diagnosis of osteosarcoma was established and confirmed by histopathology. This article reviews the sinus-occupying lesion in the following and describes the lesions originate within the maxillary sinus or arise from the adjacent odontogenic components. (AU)

O osteossarcoma é uma lesão relativamente rara no osso maxilar. A proximidade da lesão ao seio maxilar proporciona um espaço vazio com resistência mínima ao progresso da lesão antes de se manifestar clinicamente, o que torna o diagnóstico precoce mais crítico. Relatamos um caso de osteossarcoma maxilar em um paciente do sexo masculino de 21 anos que se apresentou com queixa principal de dor e inchaço do lado esquerdo do palato desde 2 meses antes. Uma tomografia computadorizada Cone Beam da maxila revelou uma entidade hiperintensa difusa do lado esquerdo da maxila. Seio maxilar totalmente ocupado, alargamento assimétrico do ligamento periodontal dos dentes envolvidos e reação periosteal espiculada e em raios de sol foi reconhecida. O diagnóstico de osteossarcoma foi estabelecido e confirmado por histopatologia. Este artigo analisa a lesão que ocupa o seio maxilar e descreve as lesões originadas dentro do seio maxilar ou que surgem de componentes odontogênicos adjacentes (AU)

Relationship of gray values in cone beam computed tomography and bone mineral density obtained by dual energy X-ray absorptiometry.

OBJECTIVES: The aim of this study was to assess the correlation between bone mineral density (BMD) determined with cone beam computed tomography (CBCT) gray values and BMD determined by dual energy X-ray absorptiometry (DEXA). STUDY DESIGN: Women age greater than 50 years requiring CBCT for implant treatment were included in the study. BMD was determined by calculating the mean gray value of CBCT cross-sectional images of anterior, premolar, retromolar, and tuberosity areas of the mandible and maxilla. Patients were then subjected to DEXA of the femoral neck and lumbar spine. Independent t tests, analysis of variance (ANOVA), Pearson's correlation tests, and receiver operating characteristic (ROC) evaluation were used for data analysis. RESULTS: Of 61 asymptomatic patients (mean age 64 years), 47.5% and 55.7% had abnormal BMD, based on the T-scores of the femoral neck and lumbar spine, respectively. Significant correlations were noted between the T-scores of the femoral neck and lumbar spine and the gray values of the maxillary incisor and tuberosity areas. CONCLUSIONS: A strong correlation exists between the CBCT gray values at different sites in the maxilla and the results of DEXA. A gray value less than 298 at the maxillary tuberosity can help distinguish patients with osteoporosis from normal individuals, with 66% to 67% accuracy and suggests the need for DEXA analysis.

Root morphology and number of canals in mandibular central and lateral incisors using cone beam computed tomography

Abstract Most failures in endodontic treatment of mandibular incisors are due to the presence of a missed canal specifically the lingual. This investigation aimed to examine the root morphology and number of canals in mandibular incisors using cone beam computed tomography (CBCT). Two hundred and seven patients were assessed in terms of their mandibular central and lateral incisors of CBCT. The inclusion criteria were absence of root resorption, coronal restoration or root filling and clarity and optimal resolution of images. According to the Vertucci's classification, number of roots and canals and type of canal were evaluated by two oral and maxillofacial radiologists. In order to data analysis SPSS version 16 and descriptive statistics were implemented. All mandibular incisors had one root. Most central (84.5%) and lateral (78.2%) incisors had a single canal (p= 0.065). The majority of central (54.5%) and lateral (56.5%) incisors were Vertucci's type I (p= 0.102). Prevalence of one canal in males: central (84.8%), lateral (77.9%) and in females: central (84.2%), lateral (78.5%) (p= 0.518). Prevalence of Vertucci's type I in males: central (52.3%), lateral (45.3%) and in females: central (56.1%), lateral (64.4%) (p=0.188). The prevalence of two canals was 15.5% (central) and 21.8% (lateral) in mandibular incisors. The Vertucci's type I was the most typical kinds of mandibular incisors. Considering the limitations of periapical radiography in determining canal morphology, CBCT can be helpful in case of any concern regarding root canal morphology.

Resumo A maioria das falhas no tratamento endodôntico dos incisivos mandibulares é devida à presença de um canal perdido, especificamente do lingual. Esta investigação teve como objetivo analisar a morfologia radicular e o número de canais nos incisivos inferiores utilizando a tomografia computadorizada de feixe cônico (TCFC). Duzentos e sete pacientes foram avaliados em termos de seus incisivos centrais e laterais mandibulares de TCFC. Os critérios de inclusão foram ausência de reabsorção radicular, restauração coronária ou preenchimento radicular e clareza e resolução ótima das imagens. De acordo com a classificação de Vertucci, o número de raízes e canais e o tipo de canal foram avaliados por dois radiologistas orais e maxilo-faciais. Para análise dos dados, o SPSS versão 16 e análise estatística descritiva foram implementados. Todos os incisivos inferiores tinham uma raiz. A maioria dos incisivos centrais (84,5%) e laterais (78,2%) apresentava um único canal (valor de P: 0,065). A maioria dos incisivos centrais (54,5%) e laterais (56,5%) eram do tipo I de Vertucci (valor de P: 0,102). Prevalência de um canal no sexo masculino: central (84,8%), lateral (77,9%) e no feminino: central (84,2%), lateral (78,5%) (valor de P: 0,518). Prevalência de Vertucci tipo I em homens: central (52,3%), lateral (45,3%) e feminina: central (56,1%), lateral (64,4%) (valor de P: 0,188). A prevalência de dois canais foi de 15,5% (central) e 21,8% (lateral) nos incisivos inferiores. O tipo I de Vertucci era dos tipos mais comuns de incisivos inferiores. Considerando as limitações da radiografia periapical na determinação da morfologia do canal, a TCFC pode ser útil em caso de qualquer preocupação com relação à morfologia do canal radicular.

Comparison of Cone-Beam Computed Tomography and Intraoral Radiography in Detection of Recurrent Caries under Composite Restorations

Abstract Secondary caries is the most common cause of dental restoration failures. This study aimed to compare the diagnostic accuracy of conventional and digital intraoral radiography and cone beam computed tomography (CBCT) for detection of recurrent caries around composite restorations. mesio-occluso-distal (MOD) cavities were prepared using bur on 45 extracted sound human molar teeth. The teeth were divided into 3 groups. In the control group, cavities were restored with composite resin after etching and bonding (n=15). In Group 2, 500-μm thick wax was placed over the buccal, lingual and gingival walls and the cavities were restored with composite resin. Group 3 specimens were subjected to pH cycling and artificial caries were created on the buccal, lingual and gingival walls. The cavities were restored with composite. Conventional and digital photo-stimulable phosphor (PSP; Optime) radiographs and two CBCTs images (NewTom 3G and Cranex 3D) were obtained from them. Presence or absence of caries in the cavity walls was assessed on these images. Data were analyzed using Kappa statistic. The diagnostic accuracy of CBCT was significantly higher than that of digital and conventional intraoral radiography (p<0.05). The accuracy was 0.83, 0.78, 0.55 and 0.49 for CBCT Cranex 3D, CBCT NewTom 3G, conventional and digital intraoral radiography, respectively. CBCT has a higher diagnostic accuracy than digital and conventional intraoral radiography for detection of secondary caries around composite restorations.

Resumo A causa mais comum de falha das cáries dentais são as cáries secundárias. Este estudo objetivou comparar a acurácia diagnóstica da radiografia intraoral digital e convencional com a tomografia computadorizada de feixe cônico (TCFC) para a detecção de cáries recorrentes em torno restaurações com compósitos. Cavidades mésio-oclusais-distais (MOD) foram produzidas com broca em 45 molares hígidos humanos extraídos. Os dentes foram dividdos em 3 grupos. No grupo controle, as cavidades foram restauradas com compósito após condicionamento e colagem (n=15). No Grupo 2, foi aplicada uma camada de cera de 500 µm de espessura sobre as paredes bucais, linguais e gengivais; as cavidades foram então restauradas com resina composta. No Grupos 3, as amostras foram submetidas a ciclagem de pH e criação artificial de cáries sobre as paredes bucais, linguais e gengivais; as cavidades foram então restauradas com resina composta. Radiografias convencional e digital com fósforo foto-estimulável (PSP, Optima) e duas imagens em TCFC (NewTom 3G e Granex 3D) foram obtidas de cada amostra. A presença ou não de cáries foi avaliada nestas imagens. Os dados foram analisados por estatística Kappa. A acurácia diagnóstica da TCFC foi significantemente (p<0,05) maior que na radiografia intraoral convencional e digital. A acurácia foi de 0,83, 0,78, 0,55 e 0,49, respectivamente para TCFC Cranex 3D, TCFC NewTom 3G, a radiografia intraoral convencional e digital. A TCFC tem maior acurácia diagnóstica que a radiografia intraoral convencional e digital para detecção de cáries secundárias em torno de restaurações com compósito.

Cone Beam Computed Tomography Findings of Desmoplastic Ameloblastoma of Maxilla.

Desmoplastic ameloblastoma (DA) is one of 6 subtypes and also a rare variant of ameloblastoma. It is not recognized perfectly up to now. Although most of the conventional ameloblastomas can be diagnosed in posterior of the mandible, DA more transpires in anterior of the jaws. Our patient was a 57-year-old man with swelling in the right side of the anterior maxilla. In the medical examination bone expansion was detected with a normal covering mucosa and no discoloration. This paper provides more information about cone beam computed tomography image features of DA.

Effect of Head Position on Maxillofacial Transverse Measurements Made on the Skull and Cone Beam Computed Tomography Scans

Article Incorrect patient positioning and the resultant image distortion occur in many radiographic examinations. This study aimed to assess the effect of tilting, rotation and tipping of the head on the accuracy of maxillofacial transverse measurements made on cone beam computed tomography (CBCT) scans. The CBCT scans were obtained in central position of 10 dry human skulls. Using three-dimensional (3D) Dolphin software, six positions namely 10° and 20° tilts, rotations and tips were reconstructed of central position. Transverse distances between landmarks were measured on 3D scans and the skulls. The intraclass correlation coefficient (ICC) and the Bland-Altman plot were used to compare the mean values measured by the two observers. For most landmarks, no significant differences were noted between the mean transverse distances measured in the six positions and those measured in central position on 3D scans (p>0.005). In conclusion, all measurements of transverse distances made on 3D scans in different positions were underestimated compared to the actual values measured on the skull.

Cherubism: An Unusual Study With Long-Term Follow-Up.

Cherubism is an uncommon hereditary benign fibro-osseous disorder characterized by bilateral enlargement of the mandible and the maxilla that presents with varying degrees of involvement and a tendency toward spontaneous remission.The first visit was in 2002. A 16-year-old female was referred to an orthodontist for correction of her dental crowding. In the radiographic examination that was taken for her treatment the first time in 2002, a jaw bone lesion was discovered accidentally. X-ray panoramic imaging revealed well-defined multilocular radiolucencies involving the posterior body of the mandible and ascending rami with displaced teeth. This lesion had no effect on inferior alveolar canal and maxilla.There was no significant past medical history, and there was no family history suggestive of a similar complaint. On extraoral examination, there was no swelling in both rami of the mandible and face. Histopathological examination of the biopsy specimen showed proliferating fibrous connective tissue interspersed by multinucleated giant cells. It was diagnosed as a case nonfamilial cherubism. An extensive long-term follow-up till 12 years was maintained. In 2014, after 12-years follow-up for this lesion, panoramic imaging examination showed progress of this lesion in mandible and maxilla.

Effect of Field of View on Detection of Condyle Bone Defects Using Cone Beam Computed Tomography.

In maxillofacial imaging, cone beam computed tomography (CBCT) is currently the modality of choice for assessment of bony structures of the temporomandibular joint (TMJ). Factors affecting the quality of CBCT images can change its diagnostic accuracy. This study aimed to assess the effect of field of view (FOV) and defect size on the accuracy of CBCT scans for detection of bone defects of the TMJs. This study was conducted on 12 sound TMJs of 6 human dry skulls. Erosions and osteophytes were artificially induced in 0.5, 1, and 1.5-mm sizes on the anterior-superior part of the condyle; CBCT scans were obtained with 6, 9, and 12-inch FOVs by NewTom 3G CBCT system. Two maxillofacial radiologists evaluated the presence/absence and type of defects on CBCT scans. The Cohen kappa was calculated to assess intra- and interobserver reliability. The Mann-Whitney U test was applied to compare the diagnostic accuracy of different FOVs.In comparison of 6- and 12-inch, 9- and 12-inch FOVs in detection of different sizes of erosive lesions, difference was significant (P <0.05), whereas difference between 6- and 9 inch just in 0.5-mm erosive lesion was significant (P = 0.04). In comparison of 6- and 12-inch FOVs in detection of different sizes of osteophyte lesion, difference was significant (P < 0.05), whereas between 6- and 9-inch FOVs statistically significant difference was not observed (P > 0.05). The highest and the lowest diagnostic accuracy of CBCT scans for condyle defects were obtained with 6-inch and 12-inch FOVs, respectively. Diagnostic accuracy of CBCT scans increased with an increase in size of bone defects.