Comparison of Impact Strength and Fracture Morphology of Different Heat Cure Denture Acrylic Resins: An In vitro Study.
BACKGROUND
The fracture of acrylic resin denture is rather common occurrence and causes inconvenience to the patients. This study was carried out to evaluate and compare the impact strength and fracture morphology of four different heat cure acrylic materials.


METHODS
Acrylic resin specimens were prepared using preformed metal die of dimension 65 × 10 × 3 mm. The specimens were finished, polished and subjected to impact strength evaluation using impact testing machine. The loads at which the specimens fracture are recorded and subjected to statistical analysis. Fracture surface analysis was done. Macroscopic analysis was performed by visual inspection of the fractured surfaces using a stereoscopic microscope. About 5 mm sections of all the fragments were subjected to scanning electron microscopy for microscopic analysis to verify fracture morphology.


RESULTS
Mean values of the impact strength were compared by statistical methods. The impact strength data were subjected to variance homogeneity tests. Fracture surface analysis data was analyzed by statistical methods. The mean impact strength of Lucitone 199 was higher than Acrylyn-H, DPI Heat cure & Trevalon.


CONCLUSIONS
Within the limitations of this study, it was concluded that the impact strength of the acrylic resins is affected by the reinforcement of fibers. Increased intermediate fractures increased impact strength. Brittle fractures morphology showed fewer undercuts and clearer surface. Intermediate fractures morphology showed more undercuts than clear surfaces.
Assistant Professor, Department of Prosthodontics, College of Dental Sciences, Davangere, Karnataka, India.
B
B
Praveen
Assistant Professor, Department of Oral and Maxillofacial Surgery, College of Dental Sciences, Davangere, Karnataka, India.
Harsha V
HV
Babaji
Reader, Department of Prosthodontics, College of Dental Sciences, Davangere, Karnataka, India.
B G
BG
Prasanna
Reader, Department of Prosthodontics, AME's Dental College, Raichur, Karnataka, India.
Santosh Kumar
SK
Rajalbandi
Reader, Department of Prosthodontics, College of Dental Sciences, Davangere, Karnataka, India.
T V
TV
Shreeharsha
Reader, Department of Public Health Dentistry, College of Dental Sciences, Davangere, Karnataka, India.
G M
GM
Prashant
Denture base resin; fractographic analysis; fracture morphology; impact strength; polymethyl methacrylate