J Buchgreitz1, M Buchgreitz1, D Mortensen2, L Bjørndal2. 1. Private practice, Allerød, Denmark. 2. Section of Cariology & Endodontics, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Abstract
AIM: To evaluate ex vivo, the accuracy of a preparation procedure planned for teeth with pulp canal obliteration (PCO) using a guide rail concept based on a cone-beam computed tomography (CBCT) scan merged with an optical surface scan. METHODOLOGY: A total of 48 teeth were mounted in acrylic blocks. An apical canal preparation was created to simulate remnants of an apical root canal that acted as the target for a drill path. The test blocks were surface scanned, and merged with a CBCT scan, and a guide rail was made. A pathway for the bur was created through a metal sleeve within the guide rail into dentine. The distance was measured between the centres of the performed drill path and the apical target by two examiners. A maximum distance of 0.7 mm was defined based on the radius of the bur (0.6 mm) and the radius of a root canal just visible on a radiograph (0.1 mm). The t-test was used for evaluation, and intra- and inter-examiner reproducibility was expressed by intraclass correlation coefficients. RESULTS: The mean distance between the drill path and the target was significantly lower than 0.7 mm, and null hypothesis H0 : μ = 0.7 was rejected (CI 95%: 0.31;0.49, P < 0.001). Intra- and inter-examiner agreements reached excellent levels. CONCLUSIONS: The combined use of CBCT and optical scans for the precise construction of a guide rail led to a drill path with a precision below a risk threshold. The present technique may be a valuable tool for the negotiation of partial or complete pulp canal obliteration.
AIM: To evaluate ex vivo, the accuracy of a preparation procedure planned for teeth with pulp canal obliteration (PCO) using a guide rail concept based on a cone-beam computed tomography (CBCT) scan merged with an optical surface scan. METHODOLOGY: A total of 48 teeth were mounted in acrylic blocks. An apical canal preparation was created to simulate remnants of an apical root canal that acted as the target for a drill path. The test blocks were surface scanned, and merged with a CBCT scan, and a guide rail was made. A pathway for the bur was created through a metal sleeve within the guide rail into dentine. The distance was measured between the centres of the performed drill path and the apical target by two examiners. A maximum distance of 0.7 mm was defined based on the radius of the bur (0.6 mm) and the radius of a root canal just visible on a radiograph (0.1 mm). The t-test was used for evaluation, and intra- and inter-examiner reproducibility was expressed by intraclass correlation coefficients. RESULTS: The mean distance between the drill path and the target was significantly lower than 0.7 mm, and null hypothesis H0 : μ = 0.7 was rejected (CI 95%: 0.31;0.49, P < 0.001). Intra- and inter-examiner agreements reached excellent levels. CONCLUSIONS: The combined use of CBCT and optical scans for the precise construction of a guide rail led to a drill path with a precision below a risk threshold. The present technique may be a valuable tool for the negotiation of partial or complete pulp canal obliteration.
Authors: Ralf Krug; Julian Volland; Sebastian Reich; Sebastian Soliman; Thomas Connert; Gabriel Krastl Journal: Head Face Med Date: 2020-11-17 Impact factor: 2.246
Authors: Álvaro Zubizarreta-Macho; Ana de Pedro Muñoz; Elena Riad Deglow; Rubén Agustín-Panadero; Jesús Mena Álvarez Journal: J Clin Med Date: 2020-01-02 Impact factor: 4.241