%0 Journal Article
%T Overjet and Overbite Influence on Cyclic Masticatory Movements: A CT Study
%A Ingrid Tonni
%A Massimo Pregarz
%A Giulio Ciampalini
%A Fulvia Costantinides
%A Christiane Bodin
%J ISRN Radiology
%D 2013
%R 10.5402/2013/932805
%X Aim. To determine whether a relationship exists between the linear measurements of overjet and overbite and the interincisal space delimited by the morphology of the upper and lower incisors. Method and Materials. 30 subjects (age range from 14.1 to 34.8 years, with a median age of 23.5 years and sex ratio F/M: 5/10) with overjet and overbite equal to 2£¿mm were selected from a group of 381 individuals with a full and well-aligned dentition, no previous dental treatment, and no signs or symptoms indicative of temporomandibular disorder. Computed Tomography images of vinyl polysiloxane impressions of the 30 subjects¡¯ anterior teeth were acquired. The interincisal space was defined as Immediate Overjet Angle and was calculated on the Computed Tomography images. Results. Although the 30 subjects presented overlapping measures of overjet and overbite, the values of the Immediate Overjet Angles were different in a range of a minimum value of 12¡ã and a maximum value of 54¡ã. Conclusion. This study reveals that (1) only 30 (7.9%) of the 381 individuals considered have values of overjet and overbite equal to 2£¿mm and (2) the Immediate Overjet Angle values of the 30 subjects are not related to the values of overjet and overbite. 1. Introduction The cyclic pattern of masticatory movements is regulated by a continuous interaction between [1] (i)peripheral inputs generated by the mastication muscles, the temporomandibular joint, and the occlusion, (ii)central nervous system. Several individual occlusal factors, which affect masticatory function influencing the cyclic pattern of masticatory movements, are described in the literature: the presence or absence of dental restorations [2], the overbite (OB) [3], the overjet (OJ) [4], the inclination of the occlusal plane [5¨C8], the occlusal guidance [9¨C13], and occlusal interferences [14¨C16]. Many studies show that the pattern of masticatory movements reflects the individual pattern of the occlusal guidance [9¨C13]. Shupe et al. [17] highlighted the relationship between the anterior guidance and muscle activity. Jemt et al. [18], Ehrlich et al. [19], and Yamashita et al. [20] confirmed the influence of the upper teeth lingual morphology and inclination on muscle activity and the chewing cycle. Kimoto et al. [21] demonstrated the role of the occlusal guidance, which is strictly dependent on the occlusal morphology, as a factor which influences the masticatory function and thus the activity of masticatory muscles. Ogawa et al. [8] added that the inclination of the occlusal guidance affects the masticatory function near the
%U http://www.hindawi.com/journals/isrn.radiology/2013/932805/