Current Challenges and Concepts in the Preparation of Root Canal Systems: A Review

doi:10.1097/01.DON.0000129039.59003.9D

Journal of Endodontics

Volume 30, Issue 8, August 2004, Pages 559-567

https://doi.org/10.1097/01.DON.0000129039.59003.9D Get rights and content

Nickel-titanium rotary instruments are important adjuncts in endodontic therapy. This review attempts to identify factors that influence shaping outcomes with these files, such as preoperative root-canal anatomy and instrument tip design. Other, less significant factors include operator experience, rotational speed, and specific instrument sequence. Implications of various working length definitions and desired apical widths are correlated with clinical results.

Despite the existence of one ever-present risk factor, dental anatomy, shaping outcomes with nickel-titanium rotary instruments are mostly predictable. Current evidence indicates that wider apical preparations are feasible. Nickel-titanium rotary instruments require a preclinical training period to minimize separation risks and should be used to case-related working lengths and apical widths. However, and despite superior in vitro results, randomized, clinical trials are required to evaluate outcomes when using nickel-titanium instruments.

Section snippets

Determination and Maintenance of Working Lengths

Some additional considerations are required for the successful clinical use of NiTi rotary instruments. One of these is the effect of rotary instrumentation techniques on apical tissues, e.g., the amount of extruded debris. Filing techniques lead to more extruded debris compared with the balanced force technique (123, 124). Similarly, Lightspeed and ProFile Series 29 both forced significantly less debris apically compared to step-back instrumentation with K-Files (125, 126) and extruded similar

Conclusions

Clinically, it is important to envisage the specific purpose of canal shaping extending beyond antimicrobial efficacy. During the last four decades, several authors have reported that canal preparation has a great influence on the outcome of obturation procedures (151, 152, 153). Although common sense suggests this to be true, there is surprisingly little evidence for that proposition. In fact, although clinicians and researchers agree that canals must be obturated to the end point of the

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This study aimed to evaluate the effects from the memory-triple (MT) heat treatment on the fatigue resistance of the Reciproc by comparison with the file systems of same geometry.
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The author thanks Drs. C. I. Peters and M. Zehnder for helpful criticisms and cand med dent E. Radzik for technical assistance.

Address requests for reprints to Dr. Ove Peters, Clinic for Preventive Dentistry, Periodontology and Cariology, Center of Dental and Oral Medicine and Cranio-Maxillofacial Surgery, University of Zürich, Plattenstr. 11, CH-8028 Zurich, Switzerland. e-mail: [email protected].

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Review ArticleCurrent Challenges and Concepts in the Preparation of Root Canal Systems: A Review

Section snippets

Determination and Maintenance of Working Lengths

Conclusions

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Oral Surg Oral Med Oral Pathol

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Oral Surg Oral Med Oral Path Oral Radiol Endod

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J Am Dent Assoc

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Oral Surg Oral Med Oral Path Oral Radiol Endod

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Comparison of six files to prepare simulated root canals. Part 2

Int Endod J

The effect of root canal morphology on canal shape following instrumentation using different techniques

Int Endod J

Review Article
Current Challenges and Concepts in the Preparation of Root Canal Systems: A Review