Abstract
We researched the masticatory functions among growing children whose deciduous molars were missing. We report on the follow-up study of the chewing patterns among these patients after the placement of the space maintainers.
Subjects used in this study consisted of 20 children. Ten of them were in deciduous/early mixed dentition and whose lower first primary molars were missing on one side. The age when they lost their primary molars ranged from 4Y0M to 6Y7M. A Cr-loop was placed at the extraction space as a space maintainer in each patient.
The mandibular movements when chewing gum and peanuts had been monitored longitudinally with the MKG-K6 analysing system (MYO-TRONICS INC. Seattle). The chewing patterns of the other 10 children with good dentition in the same dental stage were also observed as a control group.
During one year of observation Cr-loops were exchanged for removable space maintainers in three children for various clinical reasons. Two children from the missing group were analyzed separately since one wearing a removable space maintainer developed anterior cross-bite after the eruption of permanent incisors and the other wearing Cr-loop showed severe dental attrition.
The results were as follows: 1) Normal chewing patterns were generally observed in the control group and on the habitual side among the missing group.2) The incidence of abnormal patterns among the missing group was higher during peanut chewing than during gum chewing.3) Among some children wearing the space maintainers, the percentage of normal patterns had risen spontaneously during observation.4) At the final examination, some children were able to chew foods habitually at the both sides.5) Children who used removable space maintainers instead of Cr-loops showed good cooperation and stable chewing patterns. These results suggest that the removable space maintainers also contributed to the improvement of their masticatory functions.
