Effects of color incorporation into bite rising material: an in-vitro study

Objectives: The purpose of this an in-vitro study is to estimate the compressive and shear bond strengths of bite riser material after color incorporation at different percentages.
Materials and methods: Fifty, freshly extracted, human premolars with an intact buccal surface, free of caries, cracks, restorations, fluorosis, fissures, or extraction-related damage, as well as not having undergone any type of endodontic or orthodontic treatment, are collected in this study. All these teeth have been extracted for orthodontic reasons, then the extracted human premolars have been distributed into five groups: (n = 10): Control (Ortho Bite), Experimental 1 (Beautiful II), Experimental 2 (Beautiful II with blue stain 5%), Experimental 3 (Beautiful II with blue stain 10%) and Experimental 4 (Beautiful II with blue stain 15%). The teeth of all groups are mounted in the center of a plastic (PVC) rings with dimensions of 19 mm external diameter, 17 mm inner diameter and 20 mm in height. The teeth are placed in a parallel manner to the analyzing rode of dental surveyor.  A small circular plastic mold (4mm diameter/3mm height) is used to attach the study materials of all groups, approximately, to the central area of the teeth’s buccal surface in an O-ring shape. A universal testing machine (GESTER International Co., LTD, Quanzhou, China) with a cross head speed of 0.5mm/min has been used for shear bond strength measurement in megapascal unit (MPa), while in compressive strength measuring, a plastic mold 6 mm height and 4 mm diameter is used to prepare 50 cylindrical specimens in a distribution similar to that of the five groups then the universal testing machine is also used to test the compressive strength in MPa at a cross head speed of 0.5mm/min.
Results: The results have been analyzed by one-way ANOVA test being followed by Scheffe test. The level of significance is set at (p <0.05). Experimental 1 group has shown the highest shear bond strength’s value, whereas Experimental 3 group have shown the highest compressive strength’s value. The one-way analysis of variance and post-hock test has shown significant difference between the control group in one hand, and the other investigational groups on the other.
Conclusions: The study has concluded that incorporating colored resin into Beautiful material particularly 10% can produce acceptable bite riser with regards to shear bond and compressive strength.
Clinical implications: The prepared bite riser, which gives more strength, could be more preferable clinically as it is less subjected to wear and fracture during treatment period. So, it decreases the time needed to re-apply which affects the enamel in addition to the expected reduction in chair time. Also, a stronger bite riser gives us confidence that there is less frequency to bracket failure during the period of treatment. In addition to that, the presence of bite riser with a different degree of color offers good chances for the dentist to rise the bite without any effects on enamel and with minimum appearance of color.