Preservation in the liquid media produces alterations in enamel surface properties

Anjum, Atia; Otsuki, Masayuki; Matin, Khairul; Tagami, Junji

doi:10.1016/j.jdent.2009.07.001

« Previous Next »Journal of Dentistry
Volume 37, Issue 11 , Pages 884-890, November 2009

Preservation in the liquid media produces alterations in enamel surface properties

Atia Anjum
- Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Corresponding author. Tel.: +81 03 5803 5483; fax: +81 03 5803 0195.
Masayuki Otsuki
- Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
Khairul Matin
- Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Center of Excellence (COE) Program for Frontier Research on Molecular Destruction and Reconstruction of Tooth and Bone at Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
Junji Tagami
- Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Center of Excellence (COE) Program for Frontier Research on Molecular Destruction and Reconstruction of Tooth and Bone at Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan

Received 2 March 2009; received in revised form 30 June 2009; accepted 1 July 2009. published online 10 July 2009.

Abstract

Objective

The aim of the study was to elucidate any alterations in nanomechanical properties and structural integrity of enamel surfaces after preservation in different liquid media.

Methods

The nanohardness and modulus of elasticity of bovine enamel blocks were measured before (control) and after storage in all of the following liquid media: human pooled saliva, physiological saline (NaCl), Deionized water (Milli-Q water) and phosphate buffered saline (PBS) for 1, 7, 14 and 30 days. Control and the 30 days preserved samples were examined by scanning electron microscopy (SEM). Data were analysed by one-way ANOVA and Dunnett T³ test.

Results

Hardness and modulus of elasticity of enamel in saliva up to 14 days showed no significant decrease compared to controls. In the case of PBS, both hardness and modulus did not change up to 30 days. The hardness values of Milli-Q water (12.06%) and NaCl (14.19%) samples were reduced significantly after just for 1 day and after 30 days were reduced to 55.59% and 61.18%, respectively. The Young's modulus of NaCl samples showed significant reduction (8.35%) after 1 day, but not for Milli-Q water samples. From 7 to 30 days, significant reductions for both samples were detected. SEM photomicrographs of samples in saliva showed widening of the inter-prismal space, while in PBS samples the structural damage was less. In the Milli-Q water group, prominent structural damage was observed and in case of NaCl, the enamel prisms were eroded.