Reciprocating instrumentation in a maxillary primary central incisor: A protocol tested in a 3D printed prototype

Abstract

Summary Background Efficient endodontic instrumentation of primary teeth is a challenge for paediatric dentists. Aim To evaluate biomechanical outcomes of endodontic instrumentation with a reciprocating system in a polymer‐prototyped primary maxillary central incisor. Design The specimen was systematically instrumented and micro‐CT scanned before and after each file. The amount of debris, percentage of non‐instrumented areas, removed dentin volume, and lower dentin thickness at specific points along the root canal were analyzed. Results A 10% increase in removed dentin volume was observed when R40 was compared to R25 (14.5% vs 4.2%). When comparing R50 with R40, this increase was only 3.4% (17.9% vs 14.5%). In the root cervical third, there was substantial reduction in dentin thickness with R50 (48.8%), followed by R40 (39.5%) and R25 (18.6%). There was no difference between R25 and R40 in the removal of dentin at the apical third (15.8%), while R50 resulted in 39.8% reduction in dentin thickness. Percentage of non‐instrumented areas were the same for all files. Accumulated debris with R40 and R50 was the same (0.19 mm³) while for R25 was 0.11 mm³. Conclusions The Reciproc® system was effective for instrumentation of a prototyped primary maxillary central incisor. The most suitable file for apical preparation was R40.

Root canal obturation materials and filling techniques for primary teeth: In vitro evaluation in polymer‐based prototyped incisors

“…The low % FC obtained at the pilot study (~50%, Table ) was probably resulted from the low quality of the root canal anatomy of the commercially available prototypes (Figure ). In fact, the use of the previously validated 3D polymer‐prototyped specimen resulted in a substantial increase in the mean % FC (~90%). This methodology provided more reproducibility of the real root canal particularities and a material density more similar to dentine, resulting in more conclusive results.…”

“…A previously validated 3D‐printed, polymer prototype of an upper central incisor was used as an experimental model, which provided a much more detailed root canal internal anatomy. Sample size calculation was undertaken using data from the pilot study, being minimal difference between means (7.12%), standard deviation of the experimental error (3.43%), number of treatments (5), power of the test (0.8), and alfa error (0.05), resulting in 7 specimens per group (BioEstat v.5.3, Instituto Mamirauá).…”

Microrobotics for Precision Biofilm Diagnostics and Treatment

“…Functioning as a dynamic collective unit under the magnetic field control, aggregated microswarms can perform complex tasks and can reconfigure and adapt to the confined space (Dong et al 2021). Using 3D printed teeth replicas generated based on micro–computed tomography (CT) scans of natural human teeth (Moraes et al 2019), our data show that the aggregated microswarms can be moved and directed by the magnetic field and adapt to the variable canal geometry to reach the apical region. The size of the aggregates between the canal walls had a wide range of sizes (from 154.5 to 844.4 µm).…”

Sistema Reciproc® em Endodontia: Revisão da Literatura /

“…Reciproc® (RC) (VDW, Munique, Alemanha) e WaveOne (WO) (Dentsply-Maillefer, Ballaigues, Suíça), são caracterizados por diferentes características geométricas e projetados para trabalhar em movimento reciprocante(ARSLAN et al, 2016;MORAES et al, 2019; VILAS-BOAS et al, 2011).Por esse movimento, o instrumento gira em uma direção e depois inverte a direção antes de completar um ciclo rotativo completo(ESTEFANÍA et al, 2019). A capacidade de corte de um instrumento de canal radicular depende de um complexo inter-relacionamento entre diferentes parâmetros, como desenho transversal, ângulos helicoidais e de inclinação,propriedades metalúrgicas e tratamentos de superfície dos instrumentos(ALENAZY et al, 2018;HA et al, 2019).…”

“…No entanto, apresentaram caso clínico, bemsucedido, no qual foi utilizado o sistema Reciproc, justiçando-se pela à baixa incidência de fraturas e deformações, superiores aos instrumentos rotatórios.A proposta de técnica reciprocante em sessão única simplifica os protocolos de instrumentação e reduz a curva de aprendizado para estudantes e profissionais(DE-DEUS et al, 2015). Essa técnica mostrou desempenho favorável em relação à preparação e redução bacteriana, enquanto diminuíram consideravelmente o risco de infecção cruzada(MORAES et al, 2019).…”