AIM: To verify the influence of a functional space maintainer (FSM) in muscle strength in children with premature loss of primary molars in early mixed dentition (5.5-6.5 years old) with normal occlusion, considering the facial pattern. METHODS: The sample was distributed in: FSM Group (n = 15), with premature loss of at least one primary molar and a Control Group (n = 16). It was determined the maximal bite force (BF) with a pressurized transmitter tube, connected to a analogic/digital electronic circuit, before (t0), 1 month (t1) and 6 months (t6) after the maintainer installation. The facial pattern was determined by the Jarabak's index (FHR). Data was analyzed by descriptive statistics, variance analysis with repeated measures, t test and Pearson's correlation. RESULTS: The BF was significantly lower in t0 and t6 for FSM Group than Control Group. There was no difference in t6. Both groups presented significantly higher BF at t6 in relation to t0, but the percentage of variation was higher for FSM Group. FHR values did not correlated with the BF, and there was no difference among facial pattern intragroups. The dolichofacial children in FSM Group had values significantly lower than their matched controls in t0 and t1, but not in t6. CONCLUSION: It was concluded that the higher increase in the FM values for SFM Group after 6 month was due to the number of occlusal contacts allowed by the artificial teeth, improving the function and catching up the muscle strength.
Muscle force; Space maintainer; Mixed dentition
