Perioral Muscle Pressure Distribution In Patients With Complete Unilateral Cleft Lip And Palate In Mixed Dentition Period

Objective:The aim of this study wasto analyze the difference between the unilateral cleft lip and palate(UCLP)and non-cleft lip and palate patients in mixed dentition period in perioral muscle pressure distribution during rest position and swallowing.To study the symmetry of perioral muscle pressure in UCLP patients,locate the abnormal position and figure out the possible reasons.Providing theoretical basis on muscle function training for patients with UCLP.Methods: A total of 31 patients were selected in this study.16 patients in UCLP group(11males,5females,8.52 ±0.72 years of age),15 non-cleft crossbite patients were allocated in control group(9males,6females,8.36±0.83 years of age).Perioral force were measured before the start of orthodontic treatment.Molar area,premolar or deciduous molar area,cleft area and the canine area,central incisor was choosed as the test area.Application of SPSS 22.0 software package was used for analysis of all measured data.T-test was applied to analyze cleft vs non-cleft side of UCLP patients,left vs right sides of the non CLP group lateral vs lingual force,and so on.The peripheral force of the inner and outer orifice of the arch are not balanced,and the lateral strength of the lips is greater than that of the tongue.To analyze the difference between the UCLP group and the control group.Results:1.Perioral force was not at a balance condition between the cheek and lingual side of the dental arch,and force from cheek and lip was more powerful than the tongue(P<0.05);2.The perioral force distribution was asymmetry between the cleft side and the non-cleft side,especially at lateral area(P<0.05).The pressure distribution in lingual side was basically symmetric(P>0.05);3.The maximum force was located on the buccal side of the cleft premolars or primary molars;4.In the mouth of the patients with UCLP,perioral force was greater than the CLPpatients maxillary differences mainly reflects in the cleft zone,premolar area and the labial side of middle incisor area,mainly reflected in mandible incisors in swallowing exercise in labial side;5.The pressure between upper and lower dental arch were also unevenly distributed,force excerted on upper arch was more powerful than the lower arch.Conclusion:1.The distribution of perioral force in UCLP patients is imbalanced between cleft side and non-cleft side;upper dental arch and lower dental arch;buccal side and lingual side.The upper buccal cleft side scored much higher than other area.2.UCLP patients scored higher perioral force than NCLP patients in the cleft side of upper buccal dental arch.3.The large muscle force exerted on the cleft side of upper buccal dental arch may contributes to the growth restriction of maxillary.