J Korean Acad Prosthodont.  1998 Feb;36(1):81-103.

A STUDY ON MASTICATORY PERFORMANCE AND MUSCLE ACTIVITY IN REMOVABLE PARTIAL DENTURE WEARERS

• paik J
• Park NS

Abstract

The purpose of this study was to compare and evaluate the differences in masticatory performance, muscle activity, and patterns of occlusal contact between persons with natural dentition and removable partial denture wearers. Twenty healthy adult subjects with more than 28 teeth and thirteen removable partial denture wearers that classified Kennedy classification I was selected. The degree of pulverized rice and peanut was measured and analyzed by means of sieving method to compare the masticatory performance. For the muscle activity, EMG was recorded in selected muscles(Temporalis and masseter muscle)during mastication and resting state. The occlusal record in maximal intercuspation was taken with a silicone occlusal bite registration material for analysis of the patterns of occlusal contact. The obtained results were as follows: When chewed peanuts, masticatory performance ratio at 10-sieve size was 81.31% in natural dentition group. In removable partial denture wearer, 27.01% without RPD and 69.09% with RPD. When chewed rice, 42.04%, 11.87%, and 21.58%, respectively. The differences of masticatory performance ratio between groups were statistically significant at the 0.05 level. The mean EMG value in resting state was 1.06mV on temporal muscle, 0.98mV on masseter muscle in natural dentition group. In removable partial denture wearers, 1.13mV on temporal muscle, 1.05mV on masseter muscle without RPD and 1.11mV on temporal muscle, 1.04mV on masseter muscle with RPD. The mean EMG value during mastication was 45.64mV in natural dentition group, and in removable partial denture wearers, 22.06mV without RPD and 31.01mV with RPD when chewed peanuts. When chewed rice, 45.24mV, 25.53mV and 32.14mV, respectively. The differences of mean masticatory EMG value between groups were statistically significant at the 0.05 level. The number of posterior occlusal contact point was 20.15 in natural dentition group and 11.92 in removable partial denture wearers. The area of perforated surface was 16.50mm2in natural dentition group and 6.06mm2in removable partial denture wearers. The area of contact surface was 78.93mm2, 51.52mm2, respectively. The area of contact surface was effective to masticatory performance ratio in natural dentition group and removable partial denture wearers (P<0.05) From these results, it is concluded that in partially edentulous patient, masticatory efficiency can be improved by removable partial denture wearing, and for effcient mastication, tigth occtact surface shoud be maintained by maximum support that is provided from mucosa.

MeSH Terms

Adult
Arachis
Classification
Dentition
Denture, Partial, Removable*
Humans
Jaw Relation Record
Masseter Muscle
Mastication
Mucous Membrane
Silicones
Temporal Muscle
Tooth
Silicones