Effect of dentin pretreatment with mild acidic HOCl solution on microtensile bond strength and surface pH

Kunawarote, Sitthikorn; Nakajima, Masatoshi; Shida, Kanako; Kitasako, Yuichi; Foxton, Richard M.; Tagami, Junji

doi:10.1016/j.jdent.2009.11.006

« PreviousJournal of Dentistry
Volume 38, Issue 3 , Pages 261-268, March 2010

Effect of dentin pretreatment with mild acidic HOCl solution on microtensile bond strength and surface pH

Sitthikorn Kunawarote
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Diseases, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Corresponding author at: Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan. Tel.: +81 3 5803 5483; fax: +81 3 5803 0195.
Masatoshi Nakajima
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
Kanako Shida
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
Yuichi Kitasako
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
Richard M. Foxton
- Department of Conservative Dentistry, Guy's, King's and St. Thomas’ Dental Institute, King's College London, London SE1-9RT, UK
Junji Tagami
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Diseases, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan

Received 22 October 2009; received in revised form 20 November 2009; accepted 20 November 2009. published online 30 November 2009.

Abstract

Objectives

To evaluate the pretreatment effect of mild acidic HOCl solution on the microtensile bond strength (μTBS) of a two-step self-etch adhesive to dentin and the alteration of dentin surface pH.

Methods

Thirty-nine flat ground coronal dentin specimens were divided into one control group and 12 experimental groups, which were treated with 6% NaOCl or 50, 100 and 200ppm HOCl (Comfosy^®) solutions for 5, 15 and 30s. After rinsing with running water for 30s, all the dentin surfaces were bonded with Clearfil SE Bond according to the manufacturer's instructions. After 24h water storage, the bonded specimens were sectioned and trimmed to an hourglass shape with a cross-sectional area of approximately 1.0mm² and then subjected to the μTBS test. Thirty-six mid-coronal dentin discs were used for surface pH measurement. Dentin surface pH with or without pretreatment was examined using a pH-imaging microscope (SCHEM-100). The μTBS data were analyzed by one-way ANOVA (Dunnett's T3) and the surface pH data were analyzed by non-parametric statistics (Mann–Whitney U-test).

Results

Pretreatment with Comfosy^® at concentrations of 50, 100 and 200ppm did not significantly affect μTBS regardless of the application time compared with the control group, however the 100 and 200ppm Comfosy^® groups showed significantly lower surface pH values. For the NaOCl pretreatment groups, a longer application time significantly decreased the μTBS and increased the surface pH values compared to the control group.