Measurement of Perioral Pressures at Rest and its Correlation with Dental Parameters in Orthodontic Patients with Different Occlusions

Abstract

Introduction: Forces exerted by lips, cheeks and tongue in resting state is believed to be more important in affecting the position of teeth and malocclusion than during any activity. Muscles play the primary morphogenetic role to final size and shape of skeletal components. Hence there may be a probable relationship between the muscular pressure and structural configuration in Class I, Class II and Class III malocclusions. Aim: To evaluate perioral pressure in various malocclusions and their correlation with incisor inclination and arch width. Materials and Methods: This descriptive cross-sectional study was conducted in Department of Orthodontics, Faculty of Dental Sciences, SGT University, Budhera, Haryana with the aim of establishing a correlation between developing malocclusion and encompassing musculature which consisted of evaluation of lip and cheek pressure in different malocclusions for six months duration from April 2016 to September 2016. Out of 86 subjects who reported for orthodontic consultation in three months duration in department’s OPD; 50 subjects (32 females and 18 males) with age group range from 12 to 20 years; were advised for fixed orthodontic therapy. Before starting the treatment, they were selected for the present study and were divided into three groups based on their occlusal status; Group I (20 subjects) as Angle’s Class I; Group II (20 subjects) as Angle’s Class II division 1 (Class II/1) malocclusion and Group III (10 subjects) as Angle’s Class II division 2 (Class II/2) malocclusion. A force-sensing resistor device with a transducer thickness of less than 1 mm was used for measurements. The sensor was positioned intraorally at different sites with a thin layer of soft wax for stabilisation. Labial and buccal pressure measurements were made with lips and cheek at rest. Pressure values, cephalometric parameters, gender and arch width of all subjects were recorded. Intergroup comparison of pressure values was done using independent t-tests; where p-value <0.05 were considered as statistically significant. Correlations between upper and lower lip pressure, buccal pressure, arch width, upper and lower incisor angulation were carried out using Pearson’s correlation test. Results: Lower lip pressure was greater than upper lip pressure in all the subjects. Buccal pressure showed inverse relationship with maxillary arch width however the relationship was not significant. Maximum upper and lower lip pressure was observed in subjects with Angle’s Class II division 2 malocclusion. Conclusion: Lower lip and buccal pressure showed significant difference and hence are two chief causative factors associated with different malocclusions with minimal role of upper lip pressure. There was a moderately significant positive correlation between the upper lip pressure and the lower incisor angulation in Group III. There was no significant correlation between upper lip pressure and upper incisor angulation, lower lip pressure and upper and lower incisor angulation and buccal pressure and maxillary arch width.

Keywords

• buccal pressure
• class ii division 2 malocclusion
• force sensor
• incisor position
• lip pressure
• oral musculature