The identification of the mandibular canal (MC) is an important prerequisite for surgical procedures involving the posterior mandible. Cone beam computed tomography (CBCT) represents an advance in imaging technology, but distinguishing the MC from surrounding structures may remain a delicate task.ObjectivesThe aim of this study was to assess the visibility of the MC in different regions on CBCT cross-sectional images.Material and methodsCBCT cross-sectional images of 58 patients (116 hemi-mandibles) were analyzed, and the visibility of the MC in different regions was assessed.ResultsThe MC was clearly visible in 53% of the hemi-mandibles. Difficult and very difficult visualizations were registered in 25% and 22% of the hemi-mandibles, respectively. The visibility of the MC on distal regions was superior when compared to regions closer to the mental foramen. No differences were found between edentulous and tooth-bearing areas.ConclusionsThe MC presents an overall satisfactory visibility on CBCT cross-sectional images in most cases. However, the discrimination of the canal from its surrounds becomes less obvious towards the mental foramen region when cross-sectional images are individually analyzed.

No abstract

No abstract

Objectives: The aim of this study was to identify the type and frequency of incidental findings (IFs) in the maxillofacial region of CBCT scans with different sizes of field of view (FOV), and the clinical relevance of the findings was classified as requirement or not of monitoring, treatment or referral to a specialist. Methods: We analyzed 150 CBCT examinations, divided according to the size of the FOV into 3 groups: 6-cm maxilla, 6-cm mandible and 13-cm maxilla/mandible. The IFs were categorized into six areas: airway, temporomandibular joint (TMJ), bone, lesions of the jaws, teeth and soft-tissue calcifications. Results:The results showed 560 IFs that were found in 92% of the samples studied. A total of 225 IFs were found in examinations of the maxilla group, 99 findings in the mandible group and 236 findings in the maxilla/mandible group. The IFs were most frequent in the tooth zone (27.32%), followed by airways, soft-tissue calcifications, TMJ, bone, lesions of the jaw and other findings. We also found that 43.46% of the IFs did not need treatment or referral to another professional, 28.97% findings required the acquisition of new images for monitoring and 27.55% findings needed treatment or referral. Conclusions: The present study confirmed the high frequency of IFs in CBCT scans. It was concluded that it is necessary to interpret and report the total volume obtained in CBCT examinations and not only the purpose of the examination region.

Objectives: The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database. Methods: CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the x 2 test were used for statistical analysis. Results: AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60-to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p , 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%). Conclusions: AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population.

Based on the results, we can suggest that CBCT images are more suitable to differentiate tonsilloliths and SCO than panoramic images. The guideline was more important to diagnosis SCO than tonsilloliths. SCO was misclassified in 34% without the guideline.

No abstract

INTRODUÇÃO: a deficiência transversal da maxila é caracterizada pela atresia maxilar, palato ogival, apinhamento e rotação dos dentes, além da mordida cruzada posterior (uni ou bilateral). O tratamento dos pacientes com esta deficiência consiste no alargamento das bases ósseas maxilares. Nos pacientes com maturidade esquelética, a expansão da maxila é obtida através de procedimentos ortocirúrgicos (conhecidos como expansão de maxila cirurgicamente assistida - EMCA) que podem gerar efeitos sobre a cavidade e sobre o septo nasal. OBJETIVO: avaliar o comportamento do septo nasal frente aos procedimentos de EMCA. METODOLOGIA: foram avaliadas radiografias cefalométricas em norma póstero-anterior e radiografias oclusais totais de maxila, obtidas pela técnica convencional e posteriormente digitalizadas, de 16 pacientes submetidos à EMCA pela técnica de osteotomia Le Fort I subtotal. As radiografias foram obtidas no período pré-operatório (inicial) e pós-operatório mediato ou ao final da expansão e foram digitalizadas e mensuradas utilizando o programa DIGORA. Foram medidas, ainda, as distâncias entre os dentes (caninos, primeiro pré-molares, segundo pré-molares, primeiros molares e segundos molares). RESULTADOS: após a análise estatística pode-se constatar o aumento das distâncias interdentárias e intermaxilares, além do aumento da largura da porção basal da abertura piriforme e das distâncias entre a parede lateral da porção basal da abertura piriforme e o septo nasal. CONCLUSÃO: a EMCA é um procedimento eficaz, capaz de alargar a porção basal da abertura piriforme, que parece não influenciar no posicionamento do septo nasal.