EVALUATION OF DIFFERENT TECHNIQUES TO ENHANCE DETURE BASE ADAPTATION IN POSTERIOR PALATAL SEAL REGION- AN IN VITRO STUDY

Dr. Vivek V. Nair; Dr Prasanth. V; Dr. K .N .Velayudhan Nair; Dr.Sheela Virginia Rodrigues; Dr.K.R.Vijayanand

Volume : VI, Issue : VIII, August - 2017

EVALUATION OF DIFFERENT TECHNIQUES TO ENHANCE DETURE BASE ADAPTATION IN POSTERIOR PALATAL SEAL REGION- AN IN VITRO STUDY

Dr. Vivek V. Nair, Dr Prasanth. V, Dr. K . N . Velayudhan Nair, Dr. Sheela Virginia Rodrigues, Dr. K. R. Vijayanand

Abstract :

Me SH words:

Dental acrylic resin, maxillary complete dentures, denture processing, curing shrinkage, acrylic resin-fiber reinforcement, posterior palatal seal.

Purpose

The study investigated the efficacy of three different laboratory techniques viz,

Posterior palatal strap
Polyaramid fiber reinforcement, and
Glass fiber reinforcement, in decreasing the posterior palatal shrinkage of denture bases that occur during processing.

Materials and methods

Forty identical maxillary edentulous casts were made from high strength dental stone using a standard flexible rubber mold. An undersized wax occlusal rim was made which was duplicated in heat cure acrylic resin to be used as a standard jig throughout the study to regulate the volume of resin. Forty casts were divided into 4 groups; Group I – Control, Group II- posterior palatal strap , Group III- Kevlar 49 fiber reinforcement, and Group IV- Glass fiber reinforcement. The casts for posterior palatal strap were altered by addition of box at the base of the cast which served as a mechanical lock. In case of Kevlar fiber and Glass fiber reinforcement, pre-pregs were incorporated in the base during the packing stage. Twenty-four hours after polymerization the bases on their casts were sectioned at the posterior border at pre-designated points and evaluated for degree of adaptation using a high resolution microscope.

Results and Conclusion

Statistical analysis was performed using analysis of variance followed by 95% confidence interval test. The maximum gap was noted in mid palatine region (0.132mm) followed by maxillary tuberosity region (0.005mm) in control group. There was no measurable gap between the cast and denture base in any of the three different laboratory techniques compared. The study concluded that the fiber reinforcement technique was simply the best and most efficient when compared with the other techniques.