Apical Displacement and Residual Root Canal Filling with Single-Cone After Post Space Preparation: A Micro-CT Analysis

Abstract

The purpose of this study was to evaluate the presence of residues after post space preparation (PSP) and establish whether the apical displacement of the gutta-percha was affected by the moments and methods of PSP in teeth filled by the single-cone technique. The root canals of 20 bovine incisor teeth were instrumented with Reciproc and filled with single-cone and AH Plus. The specimens were divided into 4 groups according to the moment and method of PSP (n=5): immediate with drill, immediate with thermoplasticizer, delayed with drill and delayed with thermoplasticizer. Micro-CT scans were performed before and after the PSP for residues of the root canal filling (1) and analysis of apical displacement (2). Data were analyzed by using 2-way repeated measurement ANOVA (1) and 2-way ANOVA (2) followed by the Tukey’s test (a=0.05). Significance effect on the residues percentage remaining for methods (p=0.044), for moments (p=0.006), for thirds repetition (p<0.001), and for interaction between methods and thirds (p<0.001), and moments and thirds (p=0.044). Significance effect on the apical displacement of root canal filing was detected for methods (p=0.008), however no difference was found between moments (p=0.617). In general, PSP using drill resulted in more homogeneous root canal preparation, mainly when made immediately. For all other combinations between methods and moments for PSP, the middle and apical thirds presented significant higher residues remaining. Thermo method performed in both moments and the drill method performed immediately had displacement in the apical direction, representing extrusion of the root filling material.

Biological parameters, discolouration and radiopacity of calcium silicate‐based materials in a simulated model of partial pulpotomy

“…A sample size of 64 teeth ( n = 16 per group) was established to have a 90% chance of detection, significant at the 5% level (two‐sided test), with a minimum detectable difference of 4.96, with an expected standard deviation of 3.47. Approximately 300 central incisors from zebu cattle aged 30–36 months were initially obtained from a local abattoir (Real, Uberlândia, MG, Brazil), cleaned with a scaler, inspected and selected in four stages according to the method described by Rosatto et al (2020). A dental operating microscope (D. F. Vasconcellos, Valença, RJ, Brazil) at ×3.0 magnification was used to verify cracks or defects and the presence of open apex, followed by determination of buccolingual and mesiodistal dimensions using a digital calliper (Mitutoyo Sul Americana Ltda., Suzano, SP, Brazil).…”

Immediate and Delayed Post Space Preparations in Endodontically Treated Teeth: A Scoping Review

“…For the in vitro category, 67 studies were included (Tables 1 , 2 , 3 , 4 , 5 and 6 ). Regarding the timing of PSP, the immediate preparation times were 8 min and 22 min [ 19 ], 30 min [ 9 ], 40 min [ 8 ] in one study each, and 24 hours in four studies [ 1 , 20 – 22 ]. The exact time of immediate PSP was not reported in other included studies [ 2 , 6 , 7 , 10 , 23 – 61 ].…”

“…It is recommended that the same clinician who has performed the endodontic treatment perform PSP with a rubber dam to avoid contamination [ 9 ]. The immediate PSP allows the prepared root canal to receive the post in a unique session and to, assess the condensation of the remaining gutta-percha, and if necessary, some modifications can be considered.…”

“…However there are disagreements regarding the time interval between the root canal filling and the PSP [ 7 ]. The time of PSP may influence some outcomes in endodontically treated teeth such as void formation [ 10 ], displacement of filling material [ 9 ], the bond strength of the post [ 5 ], and post-operative pain [ 11 ]. Nevertheless, there are no consensus on the post-operative pain induced by post-endodontic restorations after single- or two-visit root canal treatments [ 11 ].…”

Effect of irrigation protocols on root canal wall after post preparation: a micro-CT and microhardness study

“…The effects of PSP on the roots filled using the single-cone technique have been previously evaluated regarding apical displacement and residual filling material. 22,23 The assessment of residual filling material using micro-CT 9,22 provides a three-dimensional view of the root canal without damaging the samples. 9 This assessment made it possible to use the same roots in the microhardness test.…”