Effect of food consistency on the shape of the articular eminence and the mandible. An experimental study on the rabbit.
The aim of this investigation was to ascertain what changes masticatory function could elicit in the shape of the articulating surface and the growth of the mandible in a growing rabbit. Forty-seven rabbits were divided into two groups, a control group fed whole pellets and a 'soft' group fed softened pellets and having their incisors shortened once a week. All the rabbits were killed at the age of 50 days and roentgenographed, after which the heads were freed of soft tissues, and the shape of the articulating eminence, the dimensions of the mandible and the maxilla, and intermaxillary relations were measured. The articulating surface of the glenoid fossa was steeper in the soft group, the lower border of the articulating eminence was located more inferiorly, and the mandible was more retrognathic. It is concluded that the difference in functional stress affects the shape of the articular eminence and the intermaxillary relationship. When the condyle is functioning more on the eminence, the latter becomes flatter, and the mandible moves forwards.
Tuominen
M
M
Department of Oral Development and Orthodontics, University of Oulu, Finland.
Kantomaa
T
T
Pirttiniemi
P
P
D000821:Animal Feed; D000818:Animals; D001696:Biomechanical Phenomena; D001732:Bite Force; D003766:Dental Occlusion; D005260:Female; D008297:Male; D008334:Mandible / Q000033:anatomy & histology / Q000254:growth & development*; D008335:Mandibular Condyle / Q000033:anatomy & histology / Q000254:growth & development; D008409:Mastication; D011817:Rabbits; D063173:Retrognathia; D013704:Temporomandibular Joint / Q000033:anatomy & histology / Q000254:growth & development* / Q000502:physiology