Facial Patterns and Masticatory Symmetries
The purpose of this study is to evaluate chewing side preference, and lateral asymmetry of occlusal contact area and bite force of individuals with different craniofacial patterns
|Study Design:||Time Perspective: Cross-Sectional|
|Official Title:||Preferred Chewing Side, Symmetry of Bite Force and Occlusal Contact Area of Subjects With Different Craniofacial Vertical Dimensions|
- Masticatory movements during mastication [ Time Frame: 2 hours ] [ Designated as safety issue: Yes ]A jaw tracking device was positioned on subjects face, who were asked to chew an artificial material in their habitual way. Tracings of jaw lateral movements during mastication were analyzed to classify in which side each chewing stroke was taken. If 80 percent or more chewing cycles were classified as left or right, the subjects were considered as unilateral chewer.
- Bite force and occlusal contact area [ Time Frame: 2 hours ] [ Designated as safety issue: Yes ]
A strain gauge was positioned on subject's first molar region unilaterally to measure the symmetry of bite force. The individual was asked to bite as hard as possible. The procedure was repeated to the other side, and the bite symmetry of sides was analyzed.
To evaluate symmetry of occlusal contact area, a registration of posterior teeth was performed with the subjects in maximal intercuspal position. The registration was digitalized, discolored, color inverted and adjusted for size to evaluate thickness of registration material using a software.
|Study Start Date:||September 2006|
|Study Completion Date:||December 2008|
|Primary Completion Date:||June 2007 (Final data collection date for primary outcome measure)|
Subjects with a horizontal facial growth pattern
Subjects with a balanced facial growth pattern
Subjects with a vertical facial growth pattern
Dolichofacial subjects presents poorer mechanical advantage, less efficiency in masticatory muscles during mastication and in generating bite force, smaller occlusal contact area and masticatory capacity when compared to brachyfacial individuals.
Wide, bilateral chewing cycles were related to better masticatory performance, however, unilateral chewing was reported to be very common in population, and it has been associated to lateral asymmetry on bite force and occlusal contact area.
It has been reported that dolichofacial subjects need greater muscular effort during mastication when compared to meso and brachyfacial subjects. This may cause functional overloading of weaker masticatory muscles, and may lead to functional asymmetries.
|Piracicaba Dental School|
|Piracicaba, São Paulo, Brazil, 13414-903|
|Principal Investigator:||Simone G Farias Gomes, PhD||Federal University of Pernambuco|
|Study Chair:||William Custodio, MS||Piracicaba Denal School, State University of Campinas|
|Study Chair:||Fernanda Faot, PhD||Federal University of Pelotas|
|Study Director:||Altair A Del Bel Cury, PhD||Piracicaba Dental School, State University of Campinas|
|Study Director:||Renata CM Rodrigues Garcia, PhD||Piracicaba Dental School, State University of Campinas|