Effect of trichloromethane on the bond strengths between acrylic teeth and different heat-cured denture bases: a...

This study is to evaluate the role of 1:1 v/v 30% trichloromethane and monomer solvent in enhancing the durability of bonding between cross-linked acrylic teeth and different heatcured denture bases with or without mechanical preparations made on ridge lap portion of the artificial teeth.

Two high impact denture base resin materials (Trevalon HI, DeTrey, UK, and DPI Tuff, Mumbai) and one nonhigh impact denture base resin material (DPI Quick Set, Mumbai) were selected to form three groups. Each group contains 30 specimens prepared by five different methods. A mixture of 30% trichloromethane and monomer, mixed in the ratio of 1:1 and applied for 1 minute on the ridge lap area of experimental specimens of methods--B, C, D and E (Specimens of method--A being control group, where no alterations were made at the ridge lap portion of acrylic teeth) before curing. Hounsfield universal testing machine is employed to evaluate the comparative bond strengths.

No significant difference was seen in bond strengths between specimens of experimental methods in all groups. When each group was assessed separately method B specimens in group 1 (739.2 N), group 2 (758 N) and method D specimens in group 3 (729 N) showed highest mean bond strengths. Control group specimens showed the least bond strength (400-460 N) in all groups with more adhesive failures.

Ridge lap portion of the specimens treated with chemical solvent as in method B showed increased bond strength in groups 1 and 2. Hence, this is a preferred method.

Evaluation of effect of different chemical and mechanical preparations at the ridge lap areas of acrylic teeth before acrylization helps the clinician and technician to overcome the problem of debonding of teeth from denture bases and in turn provides better quality prosthesis to the patient.