Potential of a New Cone-Beam CT Software for Blooming Artifact Reduction.

This study evaluated the dimensions of intraradicular posts using a new cone beam CT (CBCT) software, and verified the potential of blooming artifact reduction. Sixty-three single-rooted human teeth were shaped, obturated, prepared for intracanal post placement and distributed into three groups: G1: anatomically customized prefabricated glass fiber posts; G2: low-fusion alloy posts; G3: gold alloy posts. After post fabrication and luting with RelyX U200®, specimens were sectioned axially at 9 mm from the root apex, and markings were made on the root surfaces (X-, Y- and Z-axes). The dimensions of the original posts (control group) were measured using a digital micrometer. CBCT scans of the teeth were obtained using a PreXion 3D Elite® scanner. Posts were measured on CBCT scans using DICOM files and the e-Vol DX software. A specific filter, Blooming Artefact Reduction (BAR), was developed to analyze intracanal posts. Statistical data were evaluated using the Van de Waerden nonparametric analysis of variance and, after that, normalized data were analyzed using the Tukey test. The level of significance was set at α = 5%. The measures of the anatomical prefabricated, low-fusion alloy and gold alloy intracanal posts obtained using the e-Vol DX CBCT software and a micrometer were not significantly different (p>0.05). The use of the BAR filter of the e-Vol DX software application did not induce any dimensional differences on CBCT scans of intracanal posts when compared with measurements made with a micrometer on original posts. The use of the BAR filter eliminated blooming artifacts.

Potential of a new cone-beam ct software for blooming artifact reduction

Abstract This study evaluated the dimensions of intraradicular posts using a new cone beam CT (CBCT) software, and verified the potential of blooming artifact reduction. Sixty-three single-rooted human teeth were shaped, obturated, prepared for intracanal post placement and distributed into three groups: G1: anatomically customized prefabricated glass fiber posts; G2: low-fusion alloy posts; G3: gold alloy posts. After post fabrication and luting with RelyX U200®, specimens were sectioned axially at 9 mm from the root apex, and markings were made on the root surfaces (X-, Y- and Z-axes). The dimensions of the original posts (control group) were measured using a digital micrometer. CBCT scans of the teeth were obtained using a PreXion 3D Elite® scanner. Posts were measured on CBCT scans using DICOM files and the e-Vol DX software. A specific filter, Blooming Artefact Reduction (BAR), was developed to analyze intracanal posts. Statistical data were evaluated using the Van de Waerden nonparametric analysis of variance and, after that, normalized data were analyzed using the Tukey test. The level of significance was set at α = 5%. The measures of the anatomical prefabricated, low-fusion alloy and gold alloy intracanal posts obtained using the e-Vol DX CBCT software and a micrometer were not significantly different (p>0.05). The use of the BAR filter of the e-Vol DX software application did not induce any dimensional differences on CBCT scans of intracanal posts when compared with measurements made with a micrometer on original posts. The use of the BAR filter eliminated blooming artifacts.

Resumo Este estudo avaliou as dimensões de pinos intrarradiculares usando um novo software de tomografia computadorizada de feixe cônico (TCFC) e um micrômetro digital, e verificou o potencial da redução do artefato de contraste do branco. Sessenta e três dentes humanos unirradiculares foram modelados, obturados, preparados para colocação de pinos e distribuídos em três grupos: G1: pino de fibra de vidro pré-fabricado anatômico; G2: pino metálico de liga de baixa fusão; G3: pino metálico de liga de ouro. Após a confecção e cimentação dos pinos com RelyX U200®, os espécimes foram cortados no sentido axial a 9 mm do ápice radicular, sendo efetuadas marcações em suas superfícies radiculares (eixos X, Y e Z) para orientação das medidas e sincronizações das imagens. Foi utilizado um micrômetro digital para a mensuração das dimensões dos pinos originais (grupo controle) associado ao microscópio operatório. Posteriormente, as imagens em TCFC foram obtidas usando o PreXion 3D Elite®. Para a mensuração dos pinos nas imagens de TCFC utilizou-se o arquivo DICOM e a ferramenta de medida do software e-Vol DX, configurada para medidas milesimais, com o filtro BAR (Blooming Artifact Reduction). Os dados estatísticos foram avaliados com a análise de variância não-paramétrica de Van der Waerden, seguida pelo Teste de Tukey aplicado aos dados normalizados. O nível de significância foi de α = 5%. Os resultados mostraram que as medidas dos diâmetros dos pinos intrarradiculares (fibra de vidro anatômico, metálico liga de baixa fusão, e em liga de ouro) usando o software e-Vol DX e o micrômetro não mostram diferenças significativas entre si. O uso do filtro BAR do software e-Vol DX não induziu diferenças dimensionais nas imagens de TCFC dos pinos quando comparadas às medidas realizadas com o micrômetro sobre os pinos originais. O uso do filtro BAR eliminou artefatos de contraste do branco.

Could orthodontic fixed appliances and excess weight affect gingival health in adolescents?

INTRODUCTION: The aim of this study was to evaluate the impact of being overweight or obese while wearing orthodontic fixed appliances on the prevalence of gingivitis in adolescents. METHODS: A total of 334 adolescents, aged between 12 and 18 years, were recruited from 3 public schools in Cuiabá, Brazil. Participants were divided in dichotomized categories of body mass index (BMI) (under and normal weight or overweight and obesity) and fixed orthodontic appliance usage (yes or no). Gingival inflammation was evaluated by Löe & Silness index. Socioeconomic status was determined by the criteria of the Brazilian Association of Research Companies, and sugar consumption was assessed by a questionnaire of dietary habits. The statistical analysis was performed with P <0.05 considered significant. RESULTS: In a multivariate linear regression model, gingivitis was directly related to BMI (%) variation and orthodontic appliance use. In addition, excess weight seemed to be 2 times more relevant in predicting gingivitis than orthodontic fixed appliance usage. A strong positive correlation was observed between BMI (%) variation and gingival index (ρ = 0.97, P <0.001). CONCLUSIONS: Orthodontic fixed appliance usage and excess weight were associated with increased gingivitis in adolescents; BMI (%) variation was the most significant predictor of gingival inflammation.