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OBJECTIVE: To evaluate the influence of metal artefact reduction (MAR) in the diagnosis of dental implant contact with the mandibular canal (MC) using cone beam computed tomography (CBCT).METHODS: Dental implants were installed with surgical guides in the posterior hemiarches of 10 dry human mandibles: 0.5 mm above to the MC cortex (G1/n = 8) and 0.5 mm inside the MC (G2/n = 10). The experimental set-up was scanned with two CBCT equipment using 85 kV and 90 kV, MAR ON or OFF, and different tube currents (4 mA, 8 mA and 10 mA). Two dentomaxillofacial radiologists (DMFRs) and two dentists (DDS) scored the relation between the dental implant and MC. Descriptive statistics were used to observe the absolute frequency of scores. Sensitivity, specificity and accuracy were calculated considering the known relation between the dental implant and the MC interior. McNemar's test (α = .05) was applied to compare the diagnostic efficacy of MAR ON versus MAR OFF.RESULTS: Overall specificity was higher than sensitivity for both DDS and DMFR (97% vs. 50% and 92.0% vs. 78.0% respectively). There was a significant effect of MAR (p = .031) for DMFR in the case of contact between the dental implant with the MC interior, in which sensitivity decreased with MAR activation from 90% to 40%. DMFR observers showed a better diagnostic performance compared with the DDS observers (accuracy of 84.0% and 71.0%, respectively).CONCLUSIONS: Due to the limited efficacy of MAR, it should not be used when conducting CBCT scans for the evaluation of contact between the implant and the mandibular canal.

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. Resumen 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.

Este estudo investigou se uma amostra de restaurações de resina composta em dentes anteriores poderia ser diferentemente avaliada em diferentes centros de avaliação por avaliadores clínicos e leigos. Fotografias digitais intraorais em alta qualidade de restaurações de resina composta em dentes anteriores foram avaliadas por meio do critério FDI (1-5 escores) por pares de avaliadores clínicos e leigos no Brasil (BR), França (FR), Peru (PE), e Estados Unidos da América (EUA). Os escores foram reunidos como manter (1, 2, 3), reparar (4), e trocar (5) na comparação dos avaliadores clínicos e, como aceitável (1, 2, 3) e inaceitável (4, 5) na comparação de clínicos vs. leigos, e leigos vs. leigos. O teste qui-quadradro comparou as frequências de escores entre os centros. As frequências de manter, reparar e trocar as restaurações de resina composta em dentes anteriores dadas pelos avaliadores clínicos variou dependendo do centro de avaliação. BR e PE mostraram maiores frequências de reparo e troca, enquanto FR e EUA apresentou maiores frequências em manter. A comparação da frequência de aceitável e inaceitável dada pelos clínicos vs. leigos de um mesmo centro mostrou uma frequência significativamente maior de restaurações aceitáveis pelos avaliadores clínicos. A comparação entre os leigos de diferentes centros mostrou uma diferença significativamente maior de restaurações inaceitáveis pelo BR comparado aos leigos dos outros centros. Na avaliação de restaurações de resina composta em dentes anteriores, a tendência em manter, reparar, e trocar pode variar entre os diferentes centros de avaliação. A taxa de restaurações inaceitáveis foi mais frequentemente dada por leigos quando comparada com os avaliadores clínicos. A avaliação entre os leigos de diferentes centros variou significativamente. This study investigated whether a sample of anterior resin composite restorations could be differently evaluated in different centers of evaluation by clinical and lay evaluators. Anterior resin composite restorations on high-quality intraoral digital photography were evaluated using FDI criteria (1-5 score) by pairs of clinical and lay evaluators in Brazil (BR), France (FR), Peru (PE), and the United States of America (USA). Scores were allocated as maintenance (1, 2, 3), repair (4) and replacement (5) when comparing clinical evaluators and, as acceptable (1, 2, 3) and unacceptable (4, 5) when comparing clinical vs. lay evaluators and lay vs. lay evaluators. The Chi-square test compared the frequencies of scores among the centers. The frequencies of maintaining, repairing, or replacing anterior resin composite restorations given by clinical evaluators varied depending on the evaluation center. BR and PE showed the highest frequencies for repair and replacement, while FR and USA showed the highest frequencies for maintenance. The comparison of frequencies of anterior resin composite restorations accepted or unaccepted by the clinical vs lay evaluators in the same centers showed a significantly higher frequency of acceptable dental restorations coming from clinical evaluators. Comparison between lay evaluators from different centers showed significant higher frequency of unacceptable dental restorations by BR, compared to other centers. In the evaluation of anterior resin composite restorations, the maintenance, repair, or replacement trends can vary among different centers. The unacceptable rate came more frequently from lay than from clinical evaluators. Lay evaluators from different centers differed significantly.

Objetivo. El objetivo de este estudio fue evaluar la adaptación marginal de coronas de disilicato de litio obtenidas mediante técnicas de escaneo (CAD/CAM), antes y después de la cristalización, a través de análisis in vitro con microscopía confocal (MC). Métodos. Fueron confeccionadas 16 réplicas en poliuretano a partir de la pieza 1.4, de modelo typodont, tallada para corona total. Las réplicas fueron divididas en dos grupos, de acuerdo a la técnica de escaneo: Técnica Indirecta (Grupo IND, n=08), donde modelos de yeso fueron escaneados con escáner de laboratorio (inEos X5, Sirona Dental Systems) y Técnica Directa (Grupo DIR, n=08), donde modelos typodont fueron escaneados con escáner intraoral (CEREC BlueCam, Sirona Dental Systems). A seguir, se fresaron (inLab MC XL, Sirona Dental Systems) coronas en disilicato de litio (IPS e.max CAD, Ivoclar Vivadent) y se adaptaron a las réplicas. Se evaluó la adaptación marginal con análisis de MC en dos momentos, antes y después de la cristalización del disilicato de litio. Los datos fueron analizados con la prueba de Mann-Whitney, t de Student y Wilcoxon (α= 0,05). Resultados. Hubo una diferencia estadísticamente significativa en la adaptación marginal horizontal entre los grupos IND y DIR después de la cristalización (p=0,05). En el grupo IND, la comparación de la adaptación marginal vertical antes y después de la cristalización mostró una diferencia estadísticamente significativa (p=0,038). Conclusiones. Las coronas de disilicato de litio obtenidas mediante escaneo directo (CAD/CAM) presentaron menor desajuste marginal vertical. La etapa de cristalización afectó la adaptación marginal de las coronas.

Objective Evaluate the effects of the scanning techniques and the crystallization in the internal and marginal adaptation of milled lithium disilicate crowns by two techniques computer microtomography analysis. Materials and methods Sixteen polyurethane teeth prepared for a complete crown were divided into two groups according to the scanner method (n = 8): indirect (IND), dental stone models were scanned with laser-surface scanner, and direct (DIR), digital typodont creates with an intraoral scanner. Internal and marginal gap were evaluated by micro-computed tomography (microCT). The replica technique (RT) was applied for analysis of total volume (TV) and marginal volume (MV) gap in microCT. The data showed normal distribution (Shapiro-Wilk test). One-way ANOVA (scanner techniques) with repeated measures (crystallization) was performed. Multiple comparisons were performed with Bonferroni adjustment (α = .05). Results The axial gap showed a significant difference between the times (P = .017) for lower values after crystallization. The vertical marginal gap presented a significant difference in times for higher value after crystallization (P = .001). The marginal horizontal gap IND was greater than DIR after crystallization (P = .001) and IND before lower than after crystallization. For TV was not significant difference and MV in DIR was reduction (P = .002) after crystallization. Conclusion Crystallization changes the relationship between the crown and tooth, reducing internal gap and preventing the adequate fit in indirect and direct scanning. Clinical significance The measure gap under technological methodology is useful for adjust clinical parameters prosthetic in the CAD/CAM and the applicability of the new possibilities of analysis.

to evaluate trueness and precision of digital casts from intraoral scanning (IOS) and cone beam computed tomography (CBCT); trueness and precision of 3D-printed casts using digital light processing (DLP) and fused deposition modeling (FDM); the influence of digitizing method in the 3D-printed casts and, to compare STL data after DICOM segmentation and conversion.a reference cast was digitized with IOS and CBCT, and 3D-printed using FDM and DLP. Linear measurements of occlusocervical (OC), interarch (IEA), and mesiodistal (MD) dimensions were taken on reference, digital and 3D-printed casts. Trueness was observed as the distortion, and precision was observed as the variation of measurements. One and Two-way ANOVA, Student t-test, and Chi-Square were applied to analyze data.distortion varied between digital casts for all dimensions; at OC, both showed expanded dimensions with IOS being significantly greater; in turn, CBCT digital casts showed higher distortion at IEA and MD. Dimensions of 3D-printed casts showed a predominance of shrinkage, DLP presented higher distortion compared to FDM for both digitizing methods. Digitizing methods influenced the 3D-printing of casts, especially for DLP. Regarding precision, no statistical difference was found. STL converted from DICOM showed statistical difference in IEA (p 0.001).digital casts showed distortion depending on the digitizing method. IOS was better in IEA and MD, and CBCT in OC dimensions. Overall, DLP casts presented higher distortion compared to FDM. The digitizing method influences trueness on 3D-printed casts. File conversion from DICOM to STL per se could change the dimension.This investigation showed that digital casts from IOS and CBCT as well 3D-printed casts from FDM and DLP can show different trueness. It is clinically relevant as clinicians have various workflows available in Digital Dentistry which involve these digitizing and manufacturing methods.

This study evaluated the vertical misfit, passivity, and stress distribution after tightening the screws of different prosthesis. Two implants were used to simulate the rehabilitation of partially edentulous mandible space from the second premolar to the second molar. 40 three-element screw-retained fixed dental prosthesis with distal cantilever were fabricated and divided into four groups according to the method of production of framework (n = 10): G1 = conventional casting one-piece framework, G2 = conventional casting sectioned and laser welding, G3 = conventional casting sectioned and tungsten inert gas (TIG) welding and G4 = framework obtained by CAD/CAM (computer-aided design/computer-aided manufacturing) system. The vertical misfits (both screws tightened) and the passive fit (one screw tightened) were measured under a comparator optical microscope. The data was submitted to Shapiro-Wilk test to enable comparison with ANOVA followed by Tukey with Bonferroni adjust (α = .05). The qualitative analysis of the stress distribution was performed by the photoelastic method. The vertical misfit (both screws tightened) of the G2 (24 μm) and G3 (27 μm) were significantly higher than G4 (10 μm) (p = 0,006). The passive fit (for the non-tightened) of the G1(64 μm) and G3 (61 μm) were significantly higher than the G4 (32 μm) (p=0,009). G1 showed high stress between the implants in the photoelastic analysis and G4 presented lower stress. In conclusion, CAD/CAM method results in less vertical misfit, more passivity, and consequently better stress distribution to the bone. Resumo Neste estudo foi avaliado desajuste vertical, a passividade e a distribuição de tensões após o aperto dos parafusos de diferentes próteses. Dois implantes foram usados para simular a reabilitação do espaço edêntulo da mandíbula do segundo pré-molar ao segundo molar. Quarenta próteses dentárias fixas parafusadas de três elementos com cantilever distal foram confeccionadas e separadas em quatro grupos de acordo com o método de obtenção da infraestrutura (n = 10): G1 = fundição convencional estrutura monobloco, G2 = fundição convencional seccionada e soldagem a laser, G3 = fundição convencional seccionada e soldagem com gás inerte de tungstênio (TIG) e G4 = infraestrutura obtida pelo sistema CAD / CAM (computer-aided design/computer-aided manufacturing). Os desajustes verticais com ambos os parafusos apertados e os desajustes relativos à avaliação de passividade com um parafuso apertado foram medidos com microscópio comparador óptico. Os dados foram submetidos ao teste de Shapiro-Wilk para comparação com ANOVA seguida de ajuste de Tukey com Bonferroni (α = 0,05). A análise qualitativa da distribuição de tensões foi realizada pelo método fotoelástico. G2 (24 μm) e G3 (27 μm) apresentaram valores significativamente maiores que G4 (10 μm) (p = 0,006) de desajuste vertical (ambos os parafusos apertados). Os valores de desajustes nos G1 (64 μm) e G3 (61 μm), do lado não apertado, foram significativamente maiores que no G4 (32 μm) (p = 0,009). G1 apresentou maior tensão entre os implantes na análise fotoelástica e G4 apresentou menor tensão. O método CAD/CAM resultou em menor desajuste, maior passividade e melhor distribuição de tensões no osso.

Objective This study investigated whether a sample of anterior resin composite restorations could be differently evaluated in different centers of evaluation by clinical and lay evaluators. Methods Anterior resin composite restorations on high-quality intraoral digital photography were evaluated using FDI criteria (1-5 score) by pairs of clinical and lay evaluators in Brazil (BR), France (FR), Peru (PE), and the United States of America (USA). Scores were allocated as maintenance (1, 2, 3), repair (4) and replacement (5) when comparing clinical evaluators and, as acceptable (1, 2, 3) and unacceptable (4, 5) when comparing clinical vs. lay evaluators and lay vs. lay evaluators. The Chi-square test compared the frequencies of scores among the centers. Results The frequencies of maintaining, repairing, or replacing anterior resin composite restorations given by clinical evaluators varied depending on the evaluation center. BR and PE showed the highest frequencies for repair and replacement, while FR and USA showed the highest frequencies for maintenance. The comparison of frequencies of anterior resin composite restorations accepted or unaccepted by the clinical vs lay evaluators in the same centers showed a significantly higher frequency of acceptable dental restorations coming from clinical evaluators. Comparison between lay evaluators from different centers showed significant higher frequency of unacceptable dental restorations by BR, compared to other centers. Conclusions In the evaluation of anterior resin composite restorations, the maintenance, repair, or replacement trends can vary among different centers. The unacceptable rate came more frequently from lay than from clinical evaluators. Lay evaluators from different centers differed significantly. Clinical Significance Clinical and lay evaluators in distant evaluation centers can present different trends when assessing anterior resin composite restoration. Multicenter evaluations can help to understand such differences and it is important because clinical decision-making based on scientific evidence comes from clinical studies done in different research centers.

EditorialNo decorrer da história do Programa de Pós Graduação em Odontologia (Reabilitação Oral), o Curso de Verão vem promovendo as pesquisas desenvolvidas no Departamento de Materiais Dentários e Prótese, com o intuito de convidar a comunidade odontológica a fazer parte desse ambiente acadêmico. Sendo assim a comissão organizadora da XII Edição do Curso de Verão do Programa de Pós Graduação em Reabilitação Oral ofereceu aos seus participantes de diversos estados do país e de outros países uma gama de oportunidades dentro da Faculdade de Odontologia de Ribeirão Preto, com a sua grade cientifica voltada para pesquisas laboratoriais e clínicas, das quais diversos docentes da unidade expuseram as suas linhas de pesquisa.Essa edição do curso atingiu proporções inimagináveis, com altos números de inscrições, nunca obtido nas versões anteriores. Além disso o engajamento da comissão organizadora juntamente com a qualidade de material apresentado pelos palestrantes proporcionaram uma experiencia que tem sido avaliada pelos participantes como única e imensurável, concretizando ainda mais a existência do curso dentro do programa e aumentando a abrangência das nossas feitorias para a população.Assim, damos início a série de Anais do Curso de Verão, da qual essa é a segunda edição que possibilitou aos seus participantes apresentarem seus trabalhos, garantindo a troca de experiencias entre as diversas universidades. Além de agradecermos a participação de todos no evento, com muita responsabilidade, dedicação e carinho. Comissão OrganizadoraXII Curso de Verão do Programa de Pós Graduação em Reabilitação OralEdição 2020

To compare direct clinical and indirect digital photographic assessment of resin composite restorations. Ninety-two posterior resin composite restorations were classified using World Dental Federation (FDI) criteria by two different clinical examiners (C1 and C2). In the same appointment of clinical assessment, intraoral high-quality digital photographs were taken and posteriorly two different digital examiners (D1 and D2) classified the images of each restoration. Restorations of each patient were assessed once by C1 and C2 independently. D1 and D2 assessed the digital images from different locations and in different time. Data were analyzed using the Cohen’s kappa coefficient, Kruskal–Wallis non-parametric test and Dunn's multiple shared test, with 95% confidence. Agreement levels varied from very good (0.81–1.00) to fair (0.21–0.40). Statistically significant differences (p

O objetivo desse estudo foi avaliar a adaptação interna e marginal de coroas de dissilicato de lítio obtida por duas técnicas disponíveis pelo sistema CAD/CAM, o escaneamento direto e indireto. As análises foram realizadas por meio do microtomógrafo computadorizado (&microCT), microscópio confocal a laser (CL) e técnica da replica (TR), em dois momentos: antes e após a cristalização do material. O dente 14 de manequim foi preparado e duplicado em silicone, obtendo 20 réplicas em resina de poliuretano. Para a formação do Grupo 1 (IND/n=08), o manequim foi moldado com moldeira de estoque e silicone de adição com técnica de moldagem simultânea e modelagem com gesso pedra tipo III e IV, totalizando oito modelos em gesso. Os modelos foram escaneados com escâner indireto. Foram fresadas oito coroas de dissilicato de lítio. Para formação do Grupo 2 (DIR/n=08), o manequim foi escaneado com escâner direto. Oito imagens foram obtidas e enviadas ao laboratório pelo programa do sistema. Da mesma forma, foram fresadas oito coroas de dissilicato de lítio. As leituras da adaptação marginal das coroas foram realizadas com as mesmas adaptadas sobre a respectiva réplica em poliuretano, no &microCT, CL, e TR. As leituras da adaptação interna foram realizadas no &microCT e TR. As análises foram realizadas antes e após a cristalização das coroas. Os dados que apresentaram distribuição normal foram analisados por ANOVA dois fatores e os dados que não apresentaram distribuição normal foram analisados por teste U de Mann-Whitey para comparação entre os Grupos e pelo teste de Wilcoxon para comparação antes e após a cristalização. Em relação à adaptação axial, foi verificada diferença significante apenas para os Tempos (p=0,017), com menores valores após a cristalização. Para a adaptação interna não foi observada diferença entre os Grupos (p>0,05) ou Tempos estudados (p>0,05). Para a adaptação marginal vertical houve diferença para o Grupo IND, com maiores valores após a cristalização independente da metodologia de análise (&microCT - p=0,001; confocal - p=0,038). Já a medida marginal horizontal apresentou resultados divergentes de acordo com a metodologia utilizada. No &microCT, IND foi maior que DIR (p=0,003) e antes maior que após a cristalização (p 0.05) or Times studied (p > 0.05). For the vertical marginal adaptation difference to the IND group, with higher values after the crystallization analysis methodology-independent (&microCT p = 0.001;-p = 0.038 confocal). Already the measure presented divergent results horizontal marginal according to the methodology used. In &microCT, IND was greater than DIR (p = 0.003) and greater than after the crystallization (p < 0.001). In confocal IND less than DIR after the crystallization (p = 0.05), and DIR, before less than after the crystallization (p = 0.005). In total volume and marginal volume of space for cementation significant difference only to the DIR, with higher values after the crystallization (total volume - p = 0.025; marginal volume - p = 0.002). The results obtained can be concluded that there is contraction of the material after the crystallization, resulting in higher leakage evidenced by the increase of the total volume of the cementing space as a result of the settling difficulty the dissilicate Crown.