Effect on the dentofacial complex of Macaca irus of functional tongue forces imparted on a palatal bar

I determined the effect tongue forces imparted on a palatal bar has on the growth and development of the dentofacial complex of the Macaca irus. Ten female Macaca irus monkeys with mixed dentition were used in this experiment. The animals were divided into four groups, two animals were treated for 30 days, two for 90 days, and four for 180 days, with the remaining two animals serving as controls. The following results were obtained. 1. There was disocclusion on the maxillary and mandibular first molars. 2. Elongation of the mandibular first molars resulted from intrusion of the maxillary first molars. 3. The maxillary complex displayed a positional change with slight clockwise rotation. 4. Growth of the frontozygomatic site in the anteroinferior direction was inhibited. 5. There was no anterosuperior mandibular growth. 6. Changes in the maxillary suture and positioning of the teeth were mainly due to the effects of the tongue function imparted on the palatal bar. With enough control of the vertical growth of the maxilla can be validated. This is one of many methods of treating Class II malocclusion.