Unprepared surface areas, accumulated hard tissue debris, and dentinal crack formation after preparation using reciprocating or rotary instruments: a study in human cadavers

Campello, Andréa F.; Marceliano-Alves, Marília Fagury Videira; Siqueira, José F.; Fonseca, Simone C. L.; Lopes, Ricardo Tadeu; Alves, Flávio R.F.

doi:10.1007/s00784-021-03922-8

Cited by 18 publications

(18 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The tunnel tapers apically and must closely follow the shape of the original canal [35]. There are unprepared areas with modern cleaning and shaping systems, though to a varying degree with each [16,17,36]. They prevent complete obturation regardless of the technique by hindering adaptation of gutta-percha to the canal walls [37].…”

Section: Literature Reviewmentioning

confidence: 99%

“…Root canals also have a complex anatomy with the occurrence of oval shaped canals in more than 90% teeth in some samples [15]. Therefore, even standard protocols for cleaning and shaping-be it using rotary, reciprocating or the self-adjusting files-can leave areas of the root canal untouched [16,17]. These areas are dependent on the action of irrigants to eliminate bacteria.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Complete Obturation—Cold Lateral Condensation vs. Thermoplastic Techniques: A Systematic Review of Micro-CT Studies

et al. 2021

View full text Add to dashboard Cite

To prevent re-infection and provide a hermetic seal of the root canal system, an endodontist must aim to produce a void-free obturation. This review aimed to compare the completeness of root canal obturation between the two most prevalent methods—cold lateral condensation and warm gutta-percha techniques—using micro-CT (PROSPERO reg no. 249815). Materials and Methods: A search of Scopus, Embase, PubMed (Medline via PubMed), and Web of Science databases was done without any time restriction according to the PRISMA protocol. Articles that compared both techniques and were published in English were included. Data was extracted and the risk of bias was assessed using an adapted tool based on previous studies. Results: A total of 141 studies were identified by the search. Following the screening and selection of articles, 9 studies were included for review. Data was extracted manually and tabulated. Most studies had a moderate risk of bias. None determined operator skill in both methods before comparison. The data extracted from the included studies suggests that both techniques produce voids in the obturation. The thermoplasticized gutta-percha techniques may result in fewer voids compared to cold lateral condensation. Conclusion: Considering the limitations of the included studies, it was concluded that neither technique could completely obturate the root canal. Thermoplasticized gutta-percha techniques showed better outcomes despite a possible learning bias in favor of cold lateral condensation. Establishing operator skills before comparison may help reduce this bias.

show abstract

Section: Literature Reviewmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Complete Obturation—Cold Lateral Condensation vs. Thermoplastic Techniques: A Systematic Review of Micro-CT Studies

et al. 2021

View full text Add to dashboard Cite

show abstract

“…It was revealed that none of the tested instruments was able to completely shape the canals, and left certain amount of untouched canal wall (UCW) after canal shaping [ 7 ]. The UCW area ranged from 3.9 ± 1.8% to 58.8 ± 8.5% among previous studies [ 7 – 18 ]. In the study of Siqueira Junior et al, the microscope examination found that UCW was covered with bacteria and/or tissue debris in the majority of specimens [ 6 ].…”

Section: Introductionmentioning

confidence: 75%

“…Mandibular incisors have been used to evaluate the efficacy of preparation files in a number of studies [ 7 – 12 , 14 , 18 ]. To the best of our knowledge, there have been no studies comparing the different preparation outcome of oval and round canals of mandibular incisors, as well as including a separate investigation of each canal third.…”

Section: Discussionmentioning

confidence: 99%

Shaping outcome of ProTaper NEXT for root canal preparation in mandibular incisors: a micro-CT study

et al. 2022

View full text Add to dashboard Cite

Background Relatively high incidence of single canals with oval or round shape were observed in human mandibular incisors. In order to investigate the influence of the root canal morphology on root canal preparation, the shaping outcome of ProTaper NEXT in oval and round canals of mandibular incisors were evaluated by using micro-computed tomography (micro-CT) analysis. Methods This experiment was approved by the School Medical Ethics Committee. The sample size calculation was conducted using G*Power software. Intact mandibular incisors with a single canal were selected. Oval canals (2 < aspect ratio (AR) ≤ 4) and round canals (AR ≤ 2) were pair-matched according to canal length, and assigned to two experimental groups (13 per group). ProTaper NEXT was used for root canal preparation for both groups. Untouched canal wall (UCW), root canal morphological parameters and three-dimensional (3D) dentin thickness were evaluated in the entire root canal and each canal third after micro-CT scanning. Statistical analysis: Data were collected and analyzed with Mann–Whitney test and Friedman test using SPSS statistics software 25 (P < 0.05). Additionally, correlations of UCW area with canal morphological parameters were also investigated. Results After root canal preparation, no significant difference was observed in all analyzed parameters in the apical third between oval and round canal groups (P > 0.05). In the coronal two thirds of the canal, the post-operative structure model index (SMI), form factor and roundness were significantly increased, while the AR was significantly decreased in both groups (P < 0.05). In addition, in the coronal two thirds, significantly more UCW and higher UCWΔ% was observed in oval canal group (P < 0.05). Furthermore, UCW correlated very strongly to canal major diameter (0.924) and initial volume (0.938), and strongly to canal form factor (− 0.724), minor diameter (0.799) and canal area (0.882). Proximal dentin wall was associated with significantly thinner pre-operative dentin thickness and higher amount of dentin removal after root canal preparation in both oval and round canal groups. Conclusions (1) Both types of canals were more conical after root canal preparation, but oval root canals tend to leave more UCW area than round canals in the coronal two thirds of mandibular incisors, which contributes to the challenge for endodontic infection control. (2) Root canal preparation usually results in excessive dentin removal in the proximal dentin wall comparing with buccal and lingual walls in both types of canals of mandibular incisors.

show abstract

“…In the present study, an artificial periodontal ligament was produced to simulate these functions, but, certainly, it is not able to reflect the natural periodontal apparatus. New approaches for microcrack evaluation included fresh or embalmed cadaveric dento-alveolar bone-blocks, as these models represent the closest to real-life condition by preserving the viscoelastic properties of the periodontal ligament and the surrounding bone, absorbing the forces applied to dental tissues during root canal procedures [39,40]. However, even if the use of cadaveric models in combination with micro-CT imaging presents the gold standard, sample acquisition is still challenging and might result in small sample sizes and inhomogeneous experimental groups regarding tooth type, root canal volume, or surface area.…”

Section: Discussionmentioning

confidence: 99%

Effectiveness of different fiber post removal techniques and their influence on dentinal microcrack formation

et al. 2021

View full text Add to dashboard Cite

Objectives The aim of this study was to evaluate the effectiveness of different fiber post removal techniques and to correlate dentinal loss with microcrack formation. Materials and methods Forty-five extracted single-rooted teeth were root canal treated and fiber posts were adhesively luted. Specimens were divided into three groups (n = 15) according to the removal technique: long-shaft round bur (EndoTracer #08, Komet, Lemgo, Germany), SonicFlex Endo (KaVo, Biberach, Germany), DT Post Removal Kit (VDW, Munich, Germany). Roots were scanned before post cementation and after post removal using micro-computed tomography. Dentin loss, residual luting material, working time, and the induction of microcracks were assessed. Statistical analysis was performed by using multiple contrast tests (max-t tests, α = 0.05). Correlations between parameters dentin loss/new microcracks and dentin loss/residual material were calculated using Kendall’s tau. Results Post removal with SonicFlex Endo resulted in the highest amount of removed dentin with significant differences to the round bur and the DT Post Removal Kit. No technique was found to completely remove the post and luting material. All techniques induced microcracks with the DT Post Removal Kit presenting the highest number of new defects. No correlation between dentin loss and new microcracks was observed. Deviations from the original root canal occurred in all groups, but no perforation was observed. Conclusions All techniques resulted in dentin loss, residual luting material, and the formation of microcracks. However, no correlation between dentin loss and the induction of microcracks was observed. Clinical relevance As all techniques resulted in microcrack formation and dentin loss, this study emphasizes the risk of iatrogenic damage due to post removal procedures.

show abstract

Unprepared surface areas, accumulated hard tissue debris, and dentinal crack formation after preparation using reciprocating or rotary instruments: a study in human cadavers

Cited by 18 publications

References 35 publications

Complete Obturation—Cold Lateral Condensation vs. Thermoplastic Techniques: A Systematic Review of Micro-CT Studies

Complete Obturation—Cold Lateral Condensation vs. Thermoplastic Techniques: A Systematic Review of Micro-CT Studies

Shaping outcome of ProTaper NEXT for root canal preparation in mandibular incisors: a micro-CT study

Effectiveness of different fiber post removal techniques and their influence on dentinal microcrack formation

Contact Info

Product

Resources

About