CAD/CAM produces dentures with improved fit
Abstract
Objectives
Resin
polymerisation shrinkage reduces the congruence of the denture base
with denture-bearing tissues and thereby decreases the retention of
conventionally fabricated dentures. CAD/CAM denture manufacturing is a
subtractive process, and polymerisation shrinkage is not an issue
anymore. Therefore, CAD/CAM dentures are assumed to show a higher
denture base congruence than conventionally fabricated dentures. It has
been the aim of this study to test this hypothesis.
Materials and methods
CAD/CAM
dentures provided by four different manufacturers (AvaDent, Merz
Dental, Whole You, Wieland/Ivoclar) were generated from ten different
master casts. Ten conventional dentures (pack and press, long-term heat
polymerisation) made from the same master casts served as control group.
The master casts and all denture bases were scanned and matched
digitally. The absolute incongruences were measured using a 2-mm mesh.
Results
Conventionally fabricated dentures showed a mean deviation of 0.105 mm, SD = 0.019
from the master cast. All CAD/CAM dentures showed lower mean
incongruences. From all CAD/CAM dentures, AvaDent Digital Dentures
showed the highest congruence with the master cast surface with a mean
deviation of 0.058 mm, SD = 0.005. Wieland Digital Dentures showed a mean deviation of 0.068 mm, SD = 0.005, Whole You Nexteeth prostheses showed a mean deviation of 0.074 mm, SD = 0.011 and Baltic Denture System prostheses showed a mean deviation of 0.086 mm, SD = 0.012.
Conclusions
CAD/CAM produces dentures with better fit than conventional dentures.
Clinical Relevance
The present study explains the clinically observed enhanced retention and lower traumatic ulcer-frequency in CAD/CAM dentures.
Comments