Designs and Applications of Intraoral Appliances in Class III Malocclusion
Pp. 306-314 (9)
Nobuyuki Ishii and Ryuzo Kanomi
Class III malocclusion results from skeletal disharmony and unfavorable
incisor inclination. Early use of intraoral appliances in Class III malocclusion would
improve the inclination of retroclined upper incisors and proclined lower incisors.
Intraoral appliances used in the upper dental arch include the posterior bite plate
containing an anterior spring and the Yanagisawa Class III (YC3) Shield. When using
the posterior bite plate, the upper anterior teeth are pushed forward by the force of the
spring. The YC3 Shield, developed by M. Yanagisawa, results in forward movement of
the upper anterior teeth by tongue pressure. Intraoral appliances used for the lower arch
are the inclined bite plate and 2x4 utility archwire. The upper anterior teeth are
protracted by the inclined plane of the bite plate, and the lower anterior teeth are
retracted by the force of a 2x4 utility archwire. Since the early use of intraoral
appliances only improves the inclination and position of the anterior teeth, they are
usually used in combination with extraoral protractors in treating early Class III
malocclusion. Bone-anchored maxillary protraction (BAMP) was recently developed by
H.J. DeClerck and coworkers. BAMP works as an extraoral protractor and provides
orthopedic correction. It consists of Class III elastics and two pairs of temporary
anchorage devices (TADs). BAMP is a novel intraoral treatment modality for growing
patients with Class III malocclusion.
Intraoral appliance, Bite plate, YC3 Shield, 2x4 utility arch, BAMP.
Kanomi Orthodontic Office, 30 Minamiekimae-cho, Himeji 670-0962, Japan.