Stimulating effect of tongue on craniofacial growth.

The influence of the tongue on craniofacial growth was studied in 96 Mini-Lewe miniature pigs. The animals were partially glossectomized at different ages and slaughtered at various intervals after operation. The skulls were macerated for biometric analysis. Mandibular growth was significantly reduced lengthwise in animals glossectomized at age 12 weeks. The role played by the tongue in orofacial growth was also indicated by the reduced width of the lower jaw. In pigs partially glossectomized at age 12 weeks, lateral growth of the entire lower jaw was reduced after eight weeks. In animals glossectomized at age six weeks, lateral growth of the lower jaw was reduced in the region of the 1st deciduous molars and the canines after glossectomy. Partial glossectomy had no significant effects on vertical growth of the lower jaw, growth of the upper jaw or overall skull growth. Shortening of the tongue in miniature pigs six weeks old resulted in no measurable jaw changes 23 weeks after surgery.