Abstract
IntroductionTo compare the lip closing force of patients with mandibular prognathism to that of patients without dentofacial anomalies.MethodsThe subject group included 62 female patients of Class III relationship with mandibular prognathism. The control group been comprised of 71 patients of Class I relationships without skeletal deformities. Maximum lip closing force and average lip closing force were measured using a Y-meter. Student’s t-test was carried out to analyse the differences between the groups. Correlation and stepwise multiple linear regression analyses were performed to analyse the relationship between lip closing force and craniofacial morphology.ResultsThe lower lip closing force of subjects with mandibular prognathism was significantly greater than that of patients in the control group (P < 0.001), while the upper lip closing force showed no difference (P > 0.05). The lower lip closing force of patients with mandibular prognathism was strongly correlated with IMPA (Lower Incisor - Mandibular Plane angle, P < 0.001) and FMA (Frankfort Plane-Mandibular Plane angle, P < 0.001). Multiple regression equations: (MaxLL) = 12.192 - 0.125 * (IMPA) + 0.082 (FMA); (AveLL) = 9.112 - 0.091 * (IMPA) + 0.054 (FMA).ConclusionsThe lower lip closing force was markedly increased in Class III patients with mandibular prognathism and was strongly correlated with lower incisor position and mandibular plane angle.
Highlights
To compare the lip closing force of patients with mandibular prognathism to that of patients without dentofacial anomalies
Studies have indicated that 63–73% of Class III malocclusions are of the skeletal type [3], while in the research of Mackay [4], those patients who required surgical correction of Class III conditions all had some degree of mandibular prognathism, which has long been viewed as one of the most severe maxillofacial deformities [5]
Mandibular prognathism, which is commonly related to Class III malocclusion, is a facial disharmony for which patients frequently seek treatments [6]
Summary
To compare the lip closing force of patients with mandibular prognathism to that of patients without dentofacial anomalies. High prevalence of Class III malocclusions has been found in Asian populations. Kitai [1] reported that 5-20% of the Japanese population possessed the characteristics of Class III malocclusion. Studies have indicated that 63–73% of Class III malocclusions are of the skeletal type [3], while in the research of Mackay [4], those patients who required surgical correction of Class III conditions all had some degree of mandibular prognathism, which has long been viewed as one of the most severe maxillofacial deformities [5]. Mandibular prognathism, which is commonly related to Class III malocclusion, is a facial disharmony for which patients frequently seek treatments [6]. Class III malocclusion is not a distinct clinical entity, and it can exist in with any number of combinations of skeletal and dental components. Muscular factors could constitute a vital component, based on commonly held perspectives
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
