<i>In Vitro</i> Evaluation of the Staining Effects of Two Intracanal Medicaments over a 3-Month Period

Abstract

Aim: The aim of this study was to evaluate in vitro the tooth color alterations associated with two intracanal medicaments, calcium hydroxide and calcium hydroxide combined with aquatic solution of chlorexidine, for up to three months post-treatment. Materials & Methods: Thirty-one intact human anterior mature teeth were used. Black adhesive tape with a 4-mm diameter window was used to standardize the enamel surface intended for color analysis. After access cavity preparation, cleaning and shaping were completed with rotary nickel-titanium files. The teeth were randomly divided into two groups (n = 15), each according to the intracanal medicament used: (A) calcium hydroxide paste (UltraCal™ XS™ Ultradent Products, Inc., USA); (B) 2% chlorhexidine aquatic solution combined with pure calcium hydroxide powder. In one tooth, no medicament was placed (pilot). The enamel surfaces were colormetrically evaluated at the following time intervals: before placing the medicaments, immediately after placement, after 1 week as well as after 1, 2 and 3 months post-treatment. The CIE color parameters (L*, a*, b*) were recorded for each material and the corresponding color differences (ΔΕ) were calculated and statistically analyzed. Results: The most significant factor in tooth discoloration was the time intervals. The most important changes of the ΔΕ values were recorded after the 1st week and after the 3rd month. L* presented an overall increase in both groups, resulting in a higher lightness of the crown color. Only L* did show significant alterations during specific time intervals. Conclusions: There is no statistically significant relationship between the type of intracanal medicament and tooth color alteration. Time is statistically the most important factor affecting the discoloration ability of Ca(OH)2, either combined with chlorexidine or not. Consequently, the clinician should always take this into account before using such medicaments for a long-term treatment.