تأثير العضة المعكوسة الخلفية أحادية الجانب الوظيفية في الفعالية العضلية الماضغة و الصدغية عند الأطفال : دراسة مقارنة

Abstract EN

Background: The forced bite causes alterations in the activity of the jaw muscles and may lead to skeletal changes with asymmetry of the face in the course of facial growth.

Aim of the study: This research aims to compare the electromyoactivity of the masseter and temporal muscles and the preferred chewing side in children with functional unilateral posterior cross bite in those with normal occlusion.

Materials and methods: The sample of the research consists of 20 children aged between 7- 10 years with mean age of (8.5 ± 1.15).

They were divided into two groups, the first group consists of 10 children with functional unilateral posterior cross bite (study group), and the second group consists of 10 children with normal occlusion (control group).

After the clinical and functional examination, surface EMG of the masseter and the temporal muscles were recorded after blindness in all the children in two positions, chewing in the right side and chewing in the left side; the preferred chewing side was determined by using Kristenson technique.

Results & Conclusion: The results showed a statistically significant difference in the EMG of the masseter and temporal muscles in children with normal occlusion (NO) and those with functional unilateral cross bite (FUCB) in the cross bite side (p< 0.05 in 95% confidence level).

A decrease in the EMG of the two muscles-of the children with FUCB compared to those with NO-was observed.

Results showed a statistically significant increase in the EMG of the masseter and temporal muscles in the side of cross bite compared to the side with normal bite in children with FUCB ( p< 0.05 in 95% confidence level ).

Results showed a statistically significant difference in the frequency of the chewing between normal bite side and the cross bite side in patient with FUCB ( p< 0.05 in 95% confidence level ).

The increase in the chewing frequency in the normal side compared to cross bite side indicates that the normal side is the preferred chewing side in children with FUCB, who were involved in this study