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Călin C, Focșăneanu AM, Paulsen F, Didilescu AC, Niță T. Shaping Efficiency of Rotary and Reciprocating Kinematics of Engine-driven Nickel-Titanium Instruments in Moderate and Severely curved Root Canals Using Microcomputed Tomography: A Systematic Review of Ex Vivo Studies. J Endod 2024; 50:907-924. [PMID: 38537784 DOI: 10.1016/j.joen.2024.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/29/2024] [Accepted: 03/18/2024] [Indexed: 04/20/2024]
Abstract
INTRODUCTION This systematic review aimed to compare reciprocating with continuous rotary instrumentation kinematics, by means of microcomputed tomography evaluations, in extracted human permanent teeth with moderate and severe canal curvatures. METHODS The research protocol was registered in the International Prospective Register of Systematic Reviews and given the reference number CRD42023404035. An electronic search was undertaken in MEDLINE (PubMed), EBSCO, Scopus, Web of Science databases until December 2021. Manual screening of issues in endodontic journals and references of relevant articles were assessed individually. The risk of bias (RoB) of the included articles was evaluated with the QUIN tool (Quality Assessment Tool for In Vitro Studies). RESULTS Among 1640 retrieved articles, 49 were included in the qualitative synthesis. Fifteen articles had low RoB, 33 articles had medium RoB, and only 1 study was at high RoB. Continuous rotary systems had better centering ability in both moderate and severe canal curvatures and resulted in less apical transportation in severely curved root canals. None of the kinematic systems was capable of instrumenting the entire canal surface area. Reciprocating kinematics systems tended to provide higher increase in surface area of severely curved canals and produced fewer dentinal microcracks in moderately curved canals. CONCLUSIONS The evidence presented in this review suggests that continuous rotary system seems to be better than reciprocating system in solving the major issues encountered during root canal instrumentation of extracted teeth with moderate and severe curvatures.
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Affiliation(s)
- Claudiu Călin
- Faculty of Dentistry, Department of Embryology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | | | - Friedrich Paulsen
- Institute of Functional and Clinical Anatomy, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Andreea C Didilescu
- Faculty of Dentistry, Department of Embryology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
| | - Tiberiu Niță
- Faculty of Dentistry, Department of Oral and Maxillofacial Surgery "Dan Theodorescu Hospital", Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
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Huang D, Wang X, Liang J, Ling J, Bian Z, Yu Q, Hou B, Chen X, Li J, Ye L, Cheng L, Xu X, Hu T, Wu H, Guo B, Su Q, Chen Z, Qiu L, Chen W, Wei X, Huang Z, Yu J, Lin Z, Zhang Q, Yang D, Zhao J, Pan S, Yang J, Wu J, Pan Y, Xie X, Deng S, Huang X, Zhang L, Yue L, Zhou X. Expert consensus on difficulty assessment of endodontic therapy. Int J Oral Sci 2024; 16:22. [PMID: 38429281 PMCID: PMC10907570 DOI: 10.1038/s41368-024-00285-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 01/19/2024] [Indexed: 03/03/2024] Open
Abstract
Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy (RCT). Recent research, encompassing bacterial etiology and advanced imaging techniques, contributes to our understanding of the root canal system's anatomy intricacies and the technique sensitivity of RCT. Success in RCT hinges on factors like patients, infection severity, root canal anatomy, and treatment techniques. Therefore, improving disease management is a key issue to combat endodontic diseases and cure periapical lesions. The clinical difficulty assessment system of RCT is established based on patient conditions, tooth conditions, root canal configuration, and root canal needing retreatment, and emphasizes pre-treatment risk assessment for optimal outcomes. The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT. These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics.
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Affiliation(s)
- Dingming Huang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xiaoyan Wang
- Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health & NMPA Key Laboratory for Dental Materials, Beijing, China
| | - Jingping Liang
- Department of Endodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Clinical Research Center for Oral Diseases, National Center for Stomatology, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Junqi Ling
- Department of Operative Dentistry and Endodontics, Hospital of Stomatology, Guanghua, School of Stomatology, Sun Yat-Sen University & Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Zhuan Bian
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Qing Yu
- Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, China
| | - Benxiang Hou
- Department of Endodontics, Beijing Stomatological Hospital, School of Stomatology, Capital Medical University, Beijing, China
| | - Xinmei Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiyao Li
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ling Ye
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xin Xu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Tao Hu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Hongkun Wu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Geriatric dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Bin Guo
- Department of Stomatology, First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Qin Su
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Zhi Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Lihong Qiu
- Department of Endodontics, School of Stomatology, China Medical University, Shenyang, China
| | - Wenxia Chen
- College of Stomatology, Hospital of Stomatology, Guangxi Medical University, Nanning, China
| | - Xi Wei
- Department of Operative Dentistry and Endodontics, Hospital of Stomatology, Guanghua, School of Stomatology, Sun Yat-Sen University & Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Zhengwei Huang
- Department of Endodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Clinical Research Center for Oral Diseases, National Center for Stomatology, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Jinhua Yu
- Department of Endodontics, School and Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Zhengmei Lin
- Department of Operative Dentistry and Endodontics, Hospital of Stomatology, Guanghua, School of Stomatology, Sun Yat-Sen University & Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Qi Zhang
- Department of Endodontics, Stomatological Hospital and Dental School of Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
| | - Deqin Yang
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
| | - Jin Zhao
- Department of Endodontics, First Affiliated Hospital of Xinjiang Medical University, and College of Stomatology of Xinjiang Medical University, Urumqi, China
| | - Shuang Pan
- Department of Endodontics, Schoolof Stomatology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jian Yang
- Department of Endodontics, The Affiliated Stomatological Hospital of Nanchang University, Nanchang, China
| | - Jiayuan Wu
- Key Laboratory of Oral Disease Research, School of Stomatology, Zunyi Medical University, Zunyi, China
| | - Yihuai Pan
- Department of Endodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Xiaoli Xie
- Department of Cariology and Endodontics, Xiangya Stomatological School, Central South University, Changsha, China
| | - Shuli Deng
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, China
| | - Xiaojing Huang
- School and Hospital of Stomatology, Fujian Medical University, Fuzhou, China
| | - Lan Zhang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lin Yue
- Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health & NMPA Key Laboratory for Dental Materials, Beijing, China.
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
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Aarthi S, Sivakumar JS, Sivakumar AA, Soundappan JS, Chittrarasu M, Jayanthi G. Comparative evaluation of incidence of dentinal defects after root canal preparation using three different endodontic retreatment systems - An in vitro study. JOURNAL OF CONSERVATIVE DENTISTRY AND ENDODONTICS 2024; 27:262-267. [PMID: 38634037 PMCID: PMC11019810 DOI: 10.4103/jcde.jcde_266_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/27/2023] [Accepted: 01/02/2024] [Indexed: 04/19/2024]
Abstract
Context Safe and efficient removal of all root filling materials from the root canal system without compromising radicular dentin structure is essential for optimal nonsurgical retreatment. Aims The aim of this study was to evaluate and compare the incidence of dentinal defects caused during root canal filling removal using conventional, rotary, and reciprocating retreatment file systems. Settings and Design A detailed protocol explaining purpose and procedures of the study was submitted to the Institutional Ethics Committee and ethical clearance obtained. Subjects and Methods Sixty human maxillary permanent central incisors were collected and decoronated to 12-mm standardized length. The canals prepared up to a master apical file size F3 with Protaper hand files, obturated using AH plus sealer, examined under the stereomicroscope (×40 magnification): Group I: Control (n = 15), Group II: Conventional (n = 15), Group III: Protaper Universal Retreatment Files (n = 15), and Group IV: Reciproc Blue (n = 15). After instrumentation, teeth were sectioned at 3, 6, and 9 mm from the apex to evaluate the presence of dentinal defects under the stereomicroscope. Statistical Analysis Used Statistics were performed using the SPSS, version, 25 (SPSS Inc., Chicago, IL, USA). Initially, normality test was done using the Shapiro-Wilk test and data were not normally distributed followed by Kruskal-Wallis test. P < 0.05 is considered statistically significant. Results Maximum percentage increase in dentinal defects was observed in Protaper Universal Retreatment Files followed by Conventional method and Reciproc Blue. Conclusions Significantly Reciproc Blue reduced the incidence of dentinal defects after root canal preparation.
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Affiliation(s)
- S. Aarthi
- Department of Conservative Dentistry, Vivekanandha Dental College for Women, Namakkal, Tamil Nadu, India
| | - J. S. Sivakumar
- Department of Conservative Dentistry, Vivekanandha Dental College for Women, Namakkal, Tamil Nadu, India
| | - A. Andamuthu Sivakumar
- Department of Conservative Dentistry, Vivekanandha Dental College for Women, Namakkal, Tamil Nadu, India
| | | | - M. Chittrarasu
- Department of Conservative Dentistry, Vivekanandha Dental College for Women, Namakkal, Tamil Nadu, India
| | - G. Jayanthi
- Department of Conservative Dentistry, Vivekanandha Dental College for Women, Namakkal, Tamil Nadu, India
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Barakat RM, Almohareb RA, Alsayyar A, Almalki F, Alharbi H. Evaluation of Dentinal Microcracks following Diode Laser- and Ultrasonic-Activated Removal of Bioceramic Material during Root Canal Retreatment. SCANNING 2022; 2022:6319743. [PMID: 36570434 PMCID: PMC9705085 DOI: 10.1155/2022/6319743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/20/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
This study is aimed at evaluating the use of microcomputed tomography (micro-CT) analysis and the dentinal microcrack formation following retreatment of bioceramic sealer employing adjunct laser-activated irrigation and ultrasonic-activated irrigation. Thirty sound human single-canal teeth (n = 30) obturated using the single-cone technique with bioceramic sealer were retreated using nickel-titanium (NiTi) rotary files. The sample was randomly divided into three equal groups: group 1, the control group, was not subjected to further treatment; group 2 underwent ultrasonic activation of irrigants; group 3 underwent active irrigation with a diode laser (980 nm wavelength). Using micro-CT, the teeth were scanned before and after retreatment protocols. Two calibrated experienced observers viewed the cross-sectional images and calculated the number of dentinal defects. The presence of any crack or craze line on the external root surface or internal canal wall was counted. Data were analyzed using Friedman's two-way analysis of variance and Fisher's exact test. Statistical significance was set at p < 0.05. A significant increase occurred in the number of cracks post retreatment protocols, specifically in the coronal and middle canal thirds, compared to pre- and postinstrumentation (p = 0.0001). However, ultrasonic- or laser-activated irrigation did not result in a significant increase in the number of cracks (p = 0.345). NiTi rotary root canal retreatment was associated with a significant increase in dentinal microcracks. However, employing ultrasonic- or laser-activated irrigation as adjunct retreatment techniques did not reveal a significant increase in dentinal microcracks within the roots.
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Affiliation(s)
- Reem M. Barakat
- Department of Clinical Dental Sciences, College of Dentistry, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Rahaf A. Almohareb
- Department of Clinical Dental Sciences, College of Dentistry, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Aljuharh Alsayyar
- Dental Intern, College of Dentistry, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Fayruz Almalki
- Dental Intern, College of Dentistry, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Hissah Alharbi
- Dental Intern, College of Dentistry, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
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Barbosa AFA, de Lima CO, Sarmento EB, Gonçalves da Cunha G, Sassone LM, Lopes RT, da Silva EJNL. Impact of minimally invasive endodontics procedures on the development of dentinal microcracks. J Endod 2022; 48:1146-1151. [PMID: 35697303 DOI: 10.1016/j.joen.2022.05.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 04/29/2022] [Accepted: 05/26/2022] [Indexed: 10/18/2022]
Abstract
INTRODUCTION To evaluate the impact of root canal preparation in teeth with ultraconservative access cavities (UltraAC) on the development of dentinal microcracks using a non-destructive longitudinal micro-CT imaging experimental model. Root canal preparation in teeth with traditional access cavities (TradAC) was used as control. METHODS Forty mandibular molars were scanned in a micro-CT device, anatomically matched, and distributed into 4 groups according to the type of access cavity and instrumentation system: traditional/Reciproc (TradAC/RC); traditional/XP-endo Shaper (TradAC/XP); ultraconservative/Reciproc (UltraAC/RC) and ultraconservative/XP-endo Shaper (UltraAC/XP). After root canal preparation, the teeth were rescanned. After reconstruction and co-registration procedures, the images were screened from the furcation level to the apex to identify the presence of dentinal microcracks. RESULTS From a total of 15340 cross-section images, 19.65% (3014 slices) had some dentinal microcrack. The qualitative analysis demonstrated the presence of some dentinal microcrack in 11%, 33%, 19%, and 15% of the images of cross-sections in TradAC/RC, TradAC/XP, UltraAC/RC, and UltraAC/XP groups, respectively. All dentinal microcracks observed after root canal preparation were already present in the corresponding images before canal instrumentation. Therefore, no new microcracks were detected, regardless of the access cavity and root canal instrumentation system. CONCLUSIONS Root canal preparation with Reciproc or XP-Endo Shaper under traditional or ultraconservative access cavities did not create dentinal microcracks in extracted mandibular molars.
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Affiliation(s)
| | | | - Estéfano Borgo Sarmento
- Departament of Endodontics, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Nuclear Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | - Luciana Moura Sassone
- Departament of Endodontics, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Ricardo Tadeu Lopes
- Department of Dentistry, Federal University of Juiz de Fora, Governador Valadares, MG, Brasil
| | - Emmanuel João Nogueira Leal da Silva
- Departament of Endodontics, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Departament of Endodontics, Grande Rio University (UNIGRANRIO), Rio de Janeiro, RJ, Brazil.
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Patel S, Bhuva B, Bose R. Vertical root fractures in root treated teeth-current status and future trends. Int Endod J 2022; 55 Suppl 3:804-826. [PMID: 35338655 PMCID: PMC9324143 DOI: 10.1111/iej.13737] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 11/28/2022]
Abstract
Vertical root fracture (VRF) is a common reason for the extraction of root filled teeth. The accurate diagnosis of VRF may be challenging due to the absence of clinical signs, whilst conventional radiographic assessment is often inconclusive. However, an understanding of the aetiology of VRFs, and more importantly, the key predisposing factors, is crucial in identifying teeth that may be susceptible. Thorough clinical examination with magnification and co-axial lighting is essential in identifying VRFs, and although CBCT is unable to reliably detect VRFs per se, the pattern of bone loss typically associated with VRF can be fully appreciated, and therefore, increases the probability of correct diagnosis and management. The prevalence of VRFs in root filled teeth is significantly greater than in teeth with vital pulps, demonstrating that the combination of loss of structural integrity, presence of pre-existing fractures and biochemical effects of loss of vitality, are highly relevant. Careful assessment of the occlusal scheme, presence of deflective contacts and identification of parafunctional habits is imperative in both preventing and managing VRFs. Furthermore, anatomical factors such as root canal morphology, may predispose certain teeth to VRF. The influence of access cavity design and root canal instrumentation protocols should be considered although the impact of these on the fracture resistance of root filled teeth is not clearly validated. The post-endodontic restoration of root filled teeth should be expedient and considerate to the residual tooth structure. Posts should be placed 'passively' and excessive 'post-space' preparation should be avoided. This narrative review aims to present the aetiology, potential predisposing factors, histopathology, diagnosis and management of VRF and present perspectives for future research. Currently, there are limited options other than extraction for the management of VRF, although root resection may be considered in multi-rooted teeth. Innovative techniques to 'repair' VRFs using both orthograde and surgical approaches require further research and validation. The prevention of VRFs is critical; identifying susceptible teeth, utilizing conservative endodontic procedures, together with expedient and appropriate post-endodontic restorative procedures is paramount to reducing the incidence of terminal VRFs.
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Affiliation(s)
- Shanon Patel
- Department of Endodontology, King's College London Dental Institute, London, UK.,Specialist Practice, London, UK
| | - Bhavin Bhuva
- Department of Endodontology, King's College London Dental Institute, London, UK
| | - Raul Bose
- Department of Endodontology, King's College London Dental Institute, London, UK
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Versiani MA, Cavalcante DM, Belladonna FG, Silva EJNL, Souza EM, De-Deus G. A critical analysis of research methods and experimental models to study dentinal microcracks. Int Endod J 2021; 55 Suppl 1:178-226. [PMID: 34743355 DOI: 10.1111/iej.13660] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 12/30/2022]
Abstract
The purpose of this narrative review was to discuss the scientific milestones that led to the current understanding of the root dentinal microcrack phenomenon based on the interplay between the usage of micro-computed tomography (micro-CT) as an analytical tool alongside a close-to-mouth experimental model. In 2009, reports on the development of dentinal microcracks in extracted teeth after root canal preparation triggered an awareness of the potential for vertical root fractures (VRFs) of endodontically treated teeth could be developed from defects created by the mechanical stress of nickel-titanium preparation systems on dentine. This assumption was taken for granted, even though no cause-effect relationship had been scientifically demonstrated. Since then, several studies using the sectioning method with extracted teeth have been published and the large discrepancy amongst their outcomes soon become evident. Moreover, the high frequency of reported dentinal microcracks largely contrasted with the clinical incidence of VRFs, raising doubts on their methodological reliability. Using micro-CT technology, it was demonstrated by several studies that, in extracted teeth, dentinal defects already existed before the endodontic procedures, indicating that the initial reports framed a non-existing cause-effect relationship between canal preparation and dentinal microcracks. Although these new findings contributed to a better comprehension of this phenomenon, the misconception that microcracks were the starting point for VRFs was only surpassed with a new in situ approach using fresh cadavers. Surprisingly, microcracks were not identified in sound teeth. As a conclusion, dentinal microcracks in extracted teeth can be considered a non-natural occurrence observed only in a laboratory set-up as a consequence of dehydration and storage conditions. Thus, dentinal microcracks shall not be considered as the starting point for VRFs as they do not manifest in non-extracted teeth. Identifying dentinal microcracks as a laboratory phenomenon highlights the impact of recent scientific developments to disclaim the clinical relevance of laboratory-obtained outcomes.
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Affiliation(s)
| | | | | | - Emmanuel João Nogueira Leal Silva
- Department of Endodontics, Fluminense Federal University, Niterói, Brazil.,Department of Endodontics, School of Dentistry, Grande Rio University (UNIGRANRIO), Duque de Caxias, Brazil
| | - Erick Miranda Souza
- Department of Dentistry II, Federal University of Maranhão, São Luís, Brazil
| | - Gustavo De-Deus
- Department of Endodontics, Fluminense Federal University, Niterói, Brazil
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