ABSTRACT Little is known about how Brazilian dentists’ treatment decisions for proximal carious lesions are compared to current evidence-based recommendations, so better understanding is needed to close any potential evidence-practice gap. Objectives: This cross-sectional study aimed to quantify the evidence-practice gap about proximal carious lesions treatment and identify dentist factors associated with this evidence-practice gap. Methods: Brazilian dentists (n=214) from Araraquara, São Paulo State, “completed a questionnaire about their dentist and practice characteristics and a translated version of the “Assessment of Caries Diagnosis and Caries Treatment” from the U.S. National Dental Practice-Based Research Network. Five radiographic images of proximal carious lesions in low-risk and high-risk patient scenarios were used. Associations between treatment recommendations and lesion, dentist, and practice characteristics were tested for statistical significance (p<0.05). Results: Lesions confined to the enamel would be restored by 35% and 71% of dentists in the low-risk and high-risk patient scenarios, respectively, suggesting a substantial evidence-practice gap given that surgical intervention of enamel lesions is not consistent with current evidence. The lesion depth threshold to recommend a permanent restoration differed between the low-risk and high-risk patient scenarios (p<0.001). Specific dentist/practice characteristics (dentist gender, graduate of a public dental school, postgraduate training, use of caries risk assessment) were significantly associated with the evidence-practice gap, but the magnitude of these differences was not major Conclusion: A substantial evidence-practice gap in treatment of proximal carious lesions was found for the sample overall, even when clinical scenarios presented low-risk patients. Global strategies are needed to close this substantial evidence-practice gap.

RESUMO Pouco se sabe se as decisões de tratamento dos dentistas brasileiros para lesões cariosas proximais são comparadas às recomendações atuais baseadas em evidências, portanto, é necessário um melhor entendimento para fechar qualquer potencial lacuna entre a evidência e a prática. Purpose: Este estudo transversal teve como objetivo quantificar a lacuna entre a evidência e a prática na decisão de tratamento das lesões cariosas proximais e identificar os fatores associados a essa lacuna entre a evidência e a prática. Methods: Cirurgiões-dentistas brasileiros (n=214) de Araraquara, Estado de São Paulo, preencheram um questionário sobre suas características odontológicas e clínicas e uma versão traduzida do “Assessment of Caries Diagnosis and Caries Treatment” da U.S. National Dental Practice-Based Research Network. Cinco imagens radiográficas de lesões cariosas proximais em cenários de pacientes de baixo risco e alto risco foram usadas. Associações entre recomendações de tratamento e lesão, dentista e características da prática foram testadas (p<0,05). Results: As lesões confinadas ao esmalte seriam restauradas por 35% e 71% dos dentistas nos cenários de pacientes de baixo risco e alto risco, respectivamente, sugerindo uma lacuna entre a evidência e a prática substancial, dado que a intervenção cirúrgica das lesões do esmalte não é consistente com as evidências atuais. O limiar de profundidade da lesão para recomendar uma restauração permanente diferiu entre os cenários de pacientes de baixo risco e alto risco (p<0,001). Características específicas do dentista/prática (sexo do dentista, graduado em uma faculdade pública, pós-graduação, uso da avaliação de risco de cárie) foram significativamente associadas à lacuna entre a evidência e a prática, mas a magnitude dessas diferenças não foi importante. Conclusions: uma lacuna entre a evidência e a prática substancial na decisão de tratamento de lesões cariosas proximais foi encontrada para a amostra como um todo, mesmo quando os cenários clínicos apresentavam pacientes de baixo risco. Estratégias globais são necessárias para fechar essa lacuna entre a evidência e a prática.

Abstract Data on dental practices related to caries risk assessment (CRA) are scarce among Brazilian dentists. This study aimed to determine the prevalence of CRA use by dentists and factors associated with its use, as well as to quantify dentists’ ratings of the importance of specific factors when treatment planning. Dentists registered at the Regional Council of Dentistry of São Paulo State – Araraquara region were sent two paper questionnaires that comprised: a) characteristics of dentists themselves, their practices, and their patients; and b) the translated version of the “Assessment of Caries Diagnosis and Caries Treatment” Questionnaire from the U.S. National Dental Practice-Based Research Network. Participants were 206 dentists who currently practiced in Araraquara and treated dental caries. Descriptive statistics and multiple logistic regression analyses were used for data analysis. Thirty-six percent of the dentists reported they perform CRA and, among them, 36% indicated they record the assessment on a special form that is kept in the patient chart. More years since dental school graduation (OR = 1.1, p = 0.002) and holding an advanced academic degree (OR=2.6, p=0.005) were associated with a higher likelihood of performing CRA, whereas exclusively using a private practice model (OR = 0.5, p = 0.016) was associated with a lower likelihood of performing CRA. The current oral hygiene and commitment to return for follow-up were the most important risk factors for treatment planning. In conclusion, CRA was not a routine procedure in daily practice among the majority of participating dentists. Specific demographic, practice and academic education characteristics were associated with performing CRA.

ABSTRACT Objective: To describe the dental practice patterns related to caries prevention in children aged 6-18 years and associated factors. Material and Methods: Dentists (n=162) from Araraquara, Brazil, completed two paper questionnaires: (1) one about characteristics of their practice and their patient population; and (2) a translated version of the “Assessment of Caries Diagnosis and Caries Treatment” Questionnaire from the National Dental Practice-Based Research Network. Regression analyses were used for data analysis (p<0.05). Results: Dentists reported using in-office fluoride (IOF) and dental sealants (DS) in 74.2% and 45.1% of their pediatric patients, respectively. Regression analysis showed that female dentists (p=0.035 for DS; p=0.044 for IOF; p=0.011 for non-prescription fluoride rinse), those with advanced degrees (p=0.032 for prescription of fluoride), those who graduated from a private dental school (p=0.018 for chlorhexidine rinse), those who provided caries prevention regimens (p<0.001 for DS; p=0.004 for IOF; p=0.013 for non-prescription fluoride rinse), those with a greater percentage of patients interested in a caries prevention regimen (p=0.007 for non-prescription fluoride rinse), those working in a private practice model (p=0.047 for prescription of fluoride) were more likely to recommend some type of preventive methods to their pediatric patients. Conclusion: Dentists reported recommending IOF to most of their pediatric patients. Certain dentists’, practices’, and patients’ characteristics were associated to some caries prevention regimens recommended by dentists.

Este estudo avaliou a resistência de união de materiais retrobturadores a cavidades retrógradas, usando uma nova metodologia. Vinte incisivos centrais superiores foram submetidos ao preparo biomecânico (lima manual #80) e seccionadas transversalmente a 2 mm do ápice e a 4 mm do primeiro corte. Os cilindros de raízes foram incluídos em resina acrílica e posicionado a 45° em relação ao plano horizontal para confecção das retrocavidades com ponta ultrassônica diamantada. Dois grupos (n = 10) foram formados de acordo com os cimentos utilizados: MTA e Super EBA. Um cone de guta-percha (#80) foi travado no limite da retrocavidade com o canal radicular. A retrocavidade foi preenchida e, após o tempo de endurecimento do cimento utilizado, o cone de guta-percha foi removido. Os espécimes foram fixados na máquina universal de ensaios Instron com a retrobturação voltada para baixo. A haste empregada para pressionar o cimento retrobturador no teste de push-out foi inserida no espaço anteriormente ocupado pela guta-percha e acionada com velocidade de cruzeta de 1,0 mm/min, para extrusão do material retroburador. Os dados foram analisados por meio do teste ANOVA (α=5%). O cimento Super EBA (6,03 ± 1,31) apresentou maior resistência de união (MPa) comparado ao cimento MTA (1,81 ± 0,45) (p> 0,05). Houve predomínio de falhas coesivas para o cimento Super EBA e falhas mistas para o MTA. O protocolo de preparação das amostras é eficaz e apresenta uma metodologia específica para avaliação da resistência de união de materiais retrobturadores à dentina. Dentre os materiais testados, o cimento Super EBA apresentou a maior resistência de união.

This study evaluated the bond strength of root-end filling materials to root-end cavities using a new methodology. Twenty maxillary central incisors were subjected to biomechanical preparation (#80 hand file) and sectioned transversally 2 mm short of the apex and 4 mm coronally to this point. The root cylinders were embedded in acrylic resin and positioned at 45° to the horizontal plane for preparation of root-end cavities with a diamond ultrasonic retrotip. Two groups (n=10) were formed according to the root-end filling material: MTA and Super EBA. A gutta-percha cone (#80) was tug-backed at the limit between the canal and the root-end cavity. The cavity was filled and the gutta-percha cone was removed after complete setting of the sealer. The specimens were placed in an Instron machine with the root-end filling turned downwards. The push-out shaft was inserted in the space previously occupied by the gutta-percha cone and run at a crosshead speed of 1.0 mm/min for pushing out the root-end filling material. Data were analyzed by ANOVA (α=5%). Super EBA (6.03±1.31) presented higher bond strength (MPa) than MTA (1.81±0.45) (p>0.05). There was a predominance of cohesive failures for Super EBA and mixed for MTA. The protocol of specimen preparation is effective and introduces a specific methodology for assessing bond strength of root-end filling materials to dentin. Among the materials, Super EBA presented the highest bond strength.

The cleaning capacity of Hero 642 nickel-titanium files, complemented by the Hero Apical instruments in flattened roots, was determined by histological analysis, considering the area of action of the instruments on the coronal walls and the presence of remaining debris. Twenty-four single-canal, human mandibular incisors were divided into three groups and prepared as follows: GI, instrumented with Hero 642 NiTi files 30/.06, 25/.06, 20/.06, 25/.06, and 30/.06; GII, instrumented as GI followed by Hero Apical size 30/.06; GIII, instrumented as GI followed by Hero Apical sizes 30/.06 and 30/.08, then returning to 30/.06 with pendulum movements. The apical thirds were prepared for histological processing, analyzed at 40× magnification and the images were examined morphometrically. Statistical analysis showed that GIII presented the best results for removing debris (5.22% ± 4.13), with more contact between the instruments and the root canal walls (19.31% ± 0.15). This differed statistically from GI (14.04% ± 4.96 debris removal, with 42.96% ± 7.11 instrument contact) and GII (12.62% ± 5.76 debris removal, with 35.01% ± 0.15 instrument contact). Root canal preparation with Hero 642, complemented by Hero Apical instruments (30/.06 and 30/.08, then re-instrumented with Hero Apical 30/.06 using pendulum movements), was more efficient for debris removal and allowed more contact of the instruments with the root canal walls. GII presented the worst results.

Este estudo availou por meio de tomografia computadorizada volumétrica de feixe cônico (cone-beam), o transporte e a capacidade de centralização de diferentes sistemas automatizados. Raízes mésio-vestibulares de primeiros molares superiores foram distribuídas em quatro grupos (n=10) de acordo com os sistemas automatizados utilizados: GI - oscilatório com lima K-Flexofile, GII - oscilatório com lima NiTiflex, GIII - rotatório com limas do sistema K3 e GIV - rotatório com limas do sistema RaCe. Realizaram-se exames tomográficos antes e após o preparo biomecânico com batente apical estabelecido em 40.02. O transporte foi mensurado a partir das menores distâncias entre a parede interna do canal e os lados mesial e distal das raízes e a capacidade de centralização pela relação entre as diferenças das mensurações obtidas na avaliação do transporte, por meio do método de análise linear voxel a voxel. O transporte foi, em média, de 0,06±0,14 mm, sendo a tendência do desvio para mesial (n=22), porém sem diferença estatística entre os grupos (p=0,4153). O índice de centralização foi, em média, de 0,15±0,65, sem diferença estatística entre os grupos (p=0,0881). Concluiu-se que o transporte e a capacidade de centralização não foram influenciados pelo tipo de movimento mecânico e instrumentos utilizados.

The present study evaluated by cone-beam computed tomography (CBCT) the apical canal transportation and centralizing ability of different automated systems after root canal preparation. The mesiobuccal canals of maxillary first molars (n=10 per group) were prepared with: GI - reciprocating system with K-Flexofile; GII - reciprocating system with NiTiFlex files; GIII - rotary system with K3 instruments; GIV - rotary system with RaCe instruments. CBCT scans were taken before and after biomechanical preparation up to a #40.02 diameter. Canal transportation was determined by measuring the smallest distance between the inner canal walls and the mesial and distal sides of the root. The centralization ability corresponded to the difference between the measurements from transportation evaluation, using the linear voxel to voxel method of analysis. The mean transportation was 0.06 ± 0.14 mm, with a tendency to deviate to the mesial side of the root (n=22), with no statistically significant difference among the groups (p=0.4153). The mean centralization index was 0.15 ± 0.65 also without statistically significant difference among the groups (p=0.0881). It may be concluded that apical canal transportation and centralization ability were not influenced by the type of mechanical movement and instruments used.