Comparison of Conventional, Rotary, and Ultrasonic Preparation, Different Final Irrigation Regimens, and 2 Sealers in Primary Molar Root Canal Therapy

Meghan Sullivan Walsh October 12, 2010

Literature Review - St. Joseph/LMC Pediatric Dentistry

Comparison of Conventional, Rotary, and Ultrasonic Preparation, Different Final Irrigation Regimens, and 2 Sealers in Primary Molar Root Canal Therapy

Resident: Meghan Sullivan Walsh

Program: Lutheran Medical Center- Providence

Article Title: Comparison of Conventional, Rotary, and Ultrasonic Preparation, Different Final Irrigation Regimens, and 2 Sealers in Primary Molar Root Canal Therapy

Authors: Harun Canoglu, DDS, PhD; Meryem U. Tekcicek, DDS, PhD; Zafer C. Cehreli, DDS, PhD

Journal: Pediatric Dentistry

Volume (number), Year, Page #’s; 28:6, 2006, pages 518-523

Major Topic: Comparison and success of three types of file systems used for preparation of a primary molar for RCT. Comparison of irrigation systems as well as sealer penetration used for RCT on a primary molar.

Overview of Method of Research:

Instrumentation assessment: Distal roots of extracted primary mandibular second molars were gathered. (Number of teeth used for this portion of the study not mentioned) The teeth were selected with non resorbed, curved distal roots. Working length determined 1 mm short of apex and the teeth were prepared using one of the three techniques. Group 1: Mechanical hand filing using a step back techniques, k-files, up to a size 30 and irrigated with NaOCL. Group 2: Crown down technique with a nickel titanium rotary Profile up to a .04/30 file. Irrigation then performed with NaOCL. Group 3: A piezzo ultrasonic instrument with K-files up to a size 30 and lastly irrigated with NaOCL. Removed dentin was measured using reference points. Zipping, the transportation of the outer wall of the apical foramen from an overextended file, was also measured.

Sealer assessment: Distal roots of 56 extracted primary mandibular molars were selected and prepared using mechanical hand filing and irrigated with NaOCL. The roots were then divided up into four groups to receive the final irrigation: Group 1: 10 ml 2.5% NaOCL. Group 2: 10 ml 10% EDTA. Group 3: 10 ml 17% EDTA. Group 4: 10 ml distilled water. Each irrigation group was then divided into two subgroups for sealer. Group one: AH PLUS Group 2: ZOE- based Sealit-Ulta. Final obturation was done with gutta percha.

Findings:

Intrumentation: No significant difference was noted between the three techniques of Intrumentation. Ultrasonic files however did show a decrease in working length as well as the incidence of zip formation. Profile instrumentation showed the best maintenance of root curvature.

Irrigation and Sealer: Final irrigation of NaOCL and distilled water failed to remove the smear layer. The removal of smear plugs by EDTA produced better tubular penetration of sealer. The best tubular penetration was noticed in Group three with 17% EDTA and AH plus as a sealer.

Key Points: Summary: Profile .04 ISO nickel titanium produced the best results and can be a good alternative to hand filing in intrumentation of primary molars. AH plus shows good tubular penetration when used with NaOCL irrigation and 17% EDTA flush. ZOE sealer following irrigation of 10%EDTA showed insufficient tubular penetration and is not recommended as a gutta percha sealer for primary molars.

Assessment of the Article: This article was a good look into the different techniques and materials used for RCT of a primary molar. However, I found that the authors had too many studies being done and too many variables. They were looking at obturation and sealers and irrigation techniques! Would have preferred them to focus on one aspect and give more detailed information regarding their findings (particularly the number of teeth used and compared in the obturation study.)