Retromolar canal diagnosed by cone-beam computed tomography and its influence in inferior alveolar nerve block / Canal retromolar diagnosticado por tomografía computarizada de haz cónico y su influencia en el bloqueo del nervio alveolar inferior

The aim of this study was to observed the anesthetic efficacy of the alveolar nerve block on nine patients that CBCT diagnosed unilateral retromolar canal on a double-blind, split-mouth approach. The assessments of patient response to thermal (pulp vitality test) and pressure (compression of soft tissue) stimuli were carried out before and 5 minutes after the inferior alveolar nerve block procedure, using both visual analog scale (VAS) and Mc Gill pain questionnaires (McG). The mean percentage of patient response decreased after alveolar nerve block, according to both VAS and McG, and was statistically similar among hemi mandibles with and without retromolar canal (Wilcoxon>0.05); however, those without retromolar canal presented greater reduction in patient response in 6 out of 9 cases. Therefore, the retromolar canal is not a determinant factor of inferior alveolar nerve block failure.

El objetivo de este estudio fue observar la eficacia anestésica del bloqueo del nervio alveolar en nueve pacientes que CBCT diagnosticó canal retromolar unilateral en un abordaje de boca dividida doble ciego. Las evaluaciones de la respuesta del paciente a los estímulos térmicos (prueba de vitalidad pulpar) y de presión (compresión de los tejidos blandos) se realizaron antes y 5 minutos después del procedimiento de bloqueo del nervio alveolar inferior, utilizando tanto la escala analógica visual (VAS) como los cuestionarios de dolor de Mc Gill ( McG). El porcentaje medio de respuesta de los pacientes disminuyó tras el bloqueo del nervio alveolar, según EVA y McG, y fue estadísticamente similar entre hemimandíbulas con y sin canal retromolar (Wilcoxon>0,05); sin embargo, aquellos sin canal retromolar presentaron mayor reducción en la respuesta del paciente en 6 de 9 casos. Por lo tanto, el canal retromolar no es un factor determinante del fracaso del bloqueo del nervio alveolar inferior.

Can the Incorporation of a Lead Foil on the Backside of Digital Receptors Produce a Better Endodontic Diagnosis?

ABSTRACT: This study evaluated influence of addition of lead foil coupled to different types of digital receptors on image noise and on diagnosis of fractured instruments in teeth without and with root filling. Twenty-six molars had their root canals (n=67) cleaned and shaped and were divided into groups with and without root filling and with and without fractured instruments. Images were acquired in PSP and CMOS sensor, with and without addition of a lead foil coupled to the digital receptors. Diagnostic values were obtained by the area under the ROC curve, and one-way ANOVA compared the groups. Noise in images was measured by the standard deviation of mean gray values in images with and without the lead foil, and compared by two-way ANOVA (a=0.05). Addition of lead foil did not interfere in the diagnostic accuracy for both digital systems (p>0.05) and did not decrease noise in the images (p>0.05). However, independently of the addition of the lead foil, the phosphor-storage plate presented higher noise compared to the sensor (p ?0.05). Addition of lead foil to the digital receptor did not interfere in image noise and with the diagnostic accuracy for detecting fracured endodontic instrument in ex-vivo conditions.

RESUMEN: Este estudio evaluó la influencia de láminas de plomo acopladas a diferentes tipos de receptores digitales sobre el ruido de la imagen y el diagnóstico de instrumentos fracturados en dientes sin y con obturación radicular. Se limpiaron y moldearon 26 molares (n = 67), se dividieron en grupos con y sin relleno radicular y con y sin instrumentos fracturados. Las imágenes se adquirieron en el sensor PSP y CMOS, con y sin adición de una lámina de plomo acoplada a los receptores digitales. Los valores diagnósticos se obtuvieron por el área bajo la curva ROC y con ANOVA de una vía comparó los grupos. El ruido en las imágenes se midió mediante la desviación estándar de los valores medios de gris en las imágenes con y sin la lámina de plomo, y se comparó mediante ANOVA bidireccional (a = 0,05). La adición de lámina de plomo no interfirió en la precisión diagnóstica de ambos sistemas digitales (p> 0,05) y no disminuyó el ruido en las imágenes (p> 0,05). Sin embargo, independientemente de la adición de la lámina de plomo, la placa de almacenamiento de fósforo presentó mayor ruido en comparación con el sensor (p?0,05). La adición de lámina de plomo al receptor digital no interfirió con el ruido de la imagen y con la precisión diagnóstica para detectar el instrumento endodóntico fracturado en condiciones ex vivo.

Additional intraoral radiographs may change the judgment regarding the final position of orthodontic mini-implants

ABSTRACT Objective: This study aimed to assess if additional vertical bitewing (VBW) and/or occlusal (OC) radiographs may change initial judgment based only on periapical radiograph (PAR) about the final position of orthodontic mini-implants (OMI). Methods: Subjective and objective analyses were performed. Radiographic images of 26 OMI were divided into four groups: PAR, PAR+VBW, PAR+OC and ALL (PAR+VBW+OC). For subjective analysis, five observers were asked to assess if the position of OMI was favorable to its success, using questionnaires with a four-point scale for responses: 1= definitely not favorable, 2= probably not favorable, 3= probably favorable, or 4= definitely favorable. Each group containing sets of images was presented to them in four different viewing sessions. Objective evaluation compared horizontal distances between OMI tip and the root nearest to the device in PAR and VBW. Results: Most of observers (3 out of 5) changed their initial judgment based on PAR about OMI position when additional radiographs were analyzed. Differences between groups (i.e. PAR vs. PAR+VBW; PAR vs. PAR+OC; and, PARvs.ALL) were statistically significant for these observers. For those that changed their judgment about OMI position, confidence level could significantly increase, decrease or even be maintained, not indicating a pattern. There was no agreement for distances between OMI tip and the root nearest to the device in PAR and VBW. Conclusion: Considering the limitations of the study, it is concluded that additional radiographic images may change the judgement about OMI final position without necessarily increasing the degree of certainty of such judgment.

RESUMO Objetivo: avaliar se a adição de radiografias interproximais verticais (IV) e/ou oclusais (OC) pode alterar o julgamento inicial sobre a posição final dos mini-implantes ortodônticos (MI) baseado somente na radiografia periapical (PA). Métodos: foram realizadas análises subjetivas e objetivas. Imagens radiográficas de 26 regiões contendo MI foram divididas em quatro grupos: PA, PA+IV, PA+OC e TODAS (PA+IV+OC). Na análise subjetiva, cinco observadores foram convidados a avaliar se a posição do MI era favorável para o seu sucesso, utilizando questionários com uma escala de quatro pontos para respostas: 1 = definitivamente não favorável; 2 = provavelmente não favorável; 3 = provavelmente favorável; ou 4 = definitivamente favorável. Cada grupo contendo conjuntos de imagens foi apresentado aos observadores em quatro sessões diferentes. Adicionalmente, uma avaliação objetiva comparou as distâncias horizontais entre a ponta do MI e a raiz dentária mais próxima ao dispositivo na PA e IV. Resultados: a maioria dos observadores (3 de 5) mudou seu julgamento inicial sobre a posição do MI baseado na PA quando radiografias adicionais foram analisadas. Diferenças entre os grupos (ou seja, PA vs PA+IV; PA vs PA+OC; e PAvsTODAS) foram estatisticamente significativas para esses observadores. Para aqueles que mudaram seu julgamento sobre a posição do MI, o nível de confiança das respostas aumentou, diminuiu ou foi mantido, não indicando um padrão. Houve diferença estatisticamente significante entre as distâncias da ponta do MI para a raiz mais próxima ao dispositivo na PA e IV. Conclusão: considerando-se as limitações desse estudo, concluiu-se que imagens radiográficas adicionais podem alterar o julgamento sobre a posição final de MI sem, necessariamente, aumentar o grau de certeza de tal julgamento.

Prevalence and morphometric analysis of three-rooted mandibular first molars in a Brazilian subpopulation

ABSTRACT The knowledge of the internal anatomy of three-rooted mandibular molars may help clinicians to diagnose and plan the root canal treatment in order to provide adequate therapy when this variation is present. Objectives: To determine the prevalence of three-rooted mandibular molars in a Brazilian population using cone beam computed tomography (CBCT) and to analyze the anatomy of mandibular first molars with three roots through micro-CT. Material and Methods: CBCT images of 116 patients were reviewed to determine the prevalence of three-rooted first mandibular molars in a Brazilian subpopulation. Furthermore, with the use of micro-CT, 55 extracted three-rooted mandibular first molars were scanned and reconstructed to assess root length, distance between canal orifices, apical diameter, Vertucci's classification, presence of apical delta, number of foramina and furcations, lateral and accessory canals. The distance between the orifice on the pulp chamber floor and the beginning of the curvature and the angle of canal curvature were analyzed in the distolingual root. Data were compared using the Kruskal-Wallis test (α=0.05). Results: The prevalence of three-rooted mandibular first molars was of 2.58%. Mesial roots showed complex distribution of the root canal system in comparison to the distal roots. The median of major diameters of mesiobuccal, mesiolingual and single mesial canals were: 0.34, 0.41 and 0.60 mm, respectively. The higher values of major diameters were found in the distobuccal canals (0.56 mm) and the lower diameters in the distolingual canals (0.29 mm). The lowest orifice distance was found between the mesial canals (MB-ML) and the highest distance between the distal root canals (DB-DL). Almost all distal roots had one root canal and one apical foramen with few accessory canals. Conclusions: Distolingual root generally has short length, severe curvature and a single root canal with low apical diameter.

Quantitative ultrasound at the hand phalanges in patients with bisphosphonate-related osteonecrosis of the jaws

Patients with bisphosphonate-related osteonecrosis of the jaws (BRONJ) who received intravenous or oral bisphosphonates (BP) were selected for determination of their bone microarchitecture as a risk predictor of BRONJ development. The diagnosis of BRONJ was made based on clinical and radiographic findings. The control group consisted of healthy patients. All patients underwent quantitative and qualitative ultrasound measurements of bone at the hand phalanges carried out using the DBM Sonic BP. Ultrasound bone profile index (UBPI), amplitude-dependent speed of sound (AD-SoS), bone biophysics profile (BBP), and bone transmission time (BTT) were measured. The BRONJ group consisted of 17 patients (62 ± 4.24; range: 45-82); 10 (58.8%) were male and seven (41.1%) were female, of whom 11 (64.7%) suffered from multiple myeloma, three (17.6%) from osteoporosis, one (5.8%) from prostate cancer, one (5.8%) from kidney cancer, and one (5.8%) from leukemia. Fourteen (82.3%) of them received intravenous BP whereas three (17.6%) received oral BP. Nine (9/17; 52.9%) patients developed bone exposure: two in the maxilla and seven in the mandible. Regarding quantitative parameters, Ad-SoS was low in the BRONJ group, but not significant. The UBPI score was significantly reduced in BRONJ patients with exposed bone when compared to controls (0.47 ± 0.12 vs. 0.70 ± 0.15; p = 0.004). The present study demonstrated that quantitative ultrasound was able to show bone microarchitecture alterations in BRONJ patients, and suggests that these analyses may be an important tool for early detection of bone degeneration associated with BRONJ.

Avaliação da alça anterior do nervo mentual por meio de tomografia computadorizada de feixe cônico / Evaluation of anterior loop of mental nerve by means of cone beam computed tomography

O forâmen mentual é um importante ponto de referência cirúrgico, sua localização e a possibilidade da existência de uma alça anterior do nervo mentual deve ser levada em consideração no planejamento cirúrgico para evitar traumas ao nervo. Nesse trabalho, avaliamos a presença da alça anterior do nervo mentual em 70 pacientes por meio de tomografia computadorizada de feixe cônico (TCFC). Os resultados revelaram uma prevalência de 32,8% da alça anterior. Nossos resultados e os encontrados na literatura atentam para uma imprevisibilidade das variações anatômicas na região do forâmen mentual. Assim, um planejamento individualizado para cada paciente deveria ser feito para minimizar os riscos de complicações pós-operatórias. A TCFC poderia ser indicada para os pacientes nos quais a anatomia da região do forâmen mentual não possa ser claramente visualizada em outros exames

The mental foramen is a surgical strategically landmark its location and the possibility of an anterior loop of the mental nerve exists mesial to the mental foramen needs to be take in consideration before implant placement to avoid nerve injury. We studied the presence of the anterior loop of mental nerve by means of CBCT in 70 patients. The results revealed a prevalence of 32,8%. Our findings together with the literature reviewed draw attention to the unpredictability of anatomical variations. Therefore, individualized anatomic assessment for each patient should be performed to minimized surgical complications. CBCT can be indicated in the cases where the anatomy of the mental foramen region is not clearly depicted in other exams

Prevalence of Supernumerary Teeth in Orthodontic Patients from Southwestern Brazil / Prevalencia de Dientes Supernumerarios en Pacientes de Ortodoncia del Suroeste de Brasil

The aim of this study was to investigate the prevalence of supernumerary teeth in a Brazilian pediatric population. One examiner evaluated the presence of supernumerary teeth in panoramic radiographs of 1719 subjects (762 male and 957 female), with ages ranging from 4 to 14.5 years (mean 8.4 years old), from the archive of the Preventive Orthodontic Course of the Rehabilitation Hospital of Bauru, São Paulo. Supernumerary teeth were present in thirty subjects (1.7 percent, 16 males and 14 females). Difference between sexes was not statistically significant. Twenty-nine supernumerary teeth (96.7 percent) were located in the maxilla, and only 1 (3.3 percent) located in mandible. Seventeen supernumerary teeth (56.7 percent) located in maxilla were mesiodens. The early diagnosis of supernumerary teeth is essential to prevent malocclusion and malposition of permanent teeth demonstrating the importance of panoramic radiographs in their detection.

El objetivo de este estudio fue investigar la prevalencia de dientes supernumerarios en una población pediátrica de Brasil. Un examinador evaluó la presencia de dientes supernumerarios en radiografías panorámicas de 1719 sujetos (762 hombres y 957 mujeres), con edades comprendidas entre 4 y 14,5 años (media 8,4 años de edad), del archivo del Curso de Ortodoncia Preventiva del Hospital de Rehabilitación de Bauru, São Paulo. Los dientes supernumerarios se presentaron en treinta sujetos (1,7 por ciento, 16 hombres y 14 mujeres). La diferencia entre sexos no fue estadísticamente significativa. Veintinueve dientes supernumerarios (96,7 por ciento) se ubicaron en el maxilar, y sólo 1 (3,3 por ciento) se ubicó en la mandíbula. Diecisiete dientes supernumerarios (56,7 por ciento) ubicados en el maxilar eran mesiodens. El diagnóstico precoz de los dientes supernumerarios es esencial para prevenir la maloclusión y malposición de los dientes permanentes, lo que demuestra la importancia de la radiografía panorámica en su detección.

Visibility of the mandibular canal on CBCT crosssectional images

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. OBJECTIVES: The aim of this study was to assess the visibility of the MC in different regions on CBCT cross-sectional images. MATERIAL AND METHODS: CBCT cross-sectional images of 58 patients (116 hemi-mandibles) were analyzed, and the visibility of the MC in different regions was assessed. RESULTS: The MC was clearly visible in 53 percent of the hemi-mandibles. Difficult and very difficult visualizations were registered in 25 percent and 22 percent 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. CONCLUSIONS: The 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.

Granuloma piogênico em paciente do sexo feminino: relato de caso clínico / Pyogenic granuloma in a female pacient: case report

O granuloma piogênico consiste em uma lesão hiperplástica inflamatória relativament comum da cavidade bucal. (...) Relatamos o caso de uma paciente adolescente do gênero feminino com uma lesão de 3 meses de evolução. O exame radiográfico revelou uma reabsorção óssea entre os dentes 15 e 16...

Pyogenic granuloma consists of a relatively common inflammatory hyperplasia in the oral cavity. (...) Our case refers to a female teenager patient with a lesion of 3 months duration. Radiographic examination reveled a hard tissue resorption between teeth 15 and 16...