The Course of the Mandibular Canal in the Growing Miniature Pig

Miniature pigs are extensively used as laboratory animals in studies concerning craniofacial growth and adaptation. However, in contrast to the vast amount of literature regarding the overall growth pattern of the pig's mandible, little is known about the internal structures of the mandible such as the mandibular canal. In order to investigate the position of the mandibular canal (MC) and the thickness of its buccal and lingual walls, a cross-sectional study was performed on female miniature pigs MINI-LEWE covering the period from newborn to adult. The position of the MC was analyzed at bony segments that were obtained by cutting the drys mandibles interdentally. At each segment a central point of the MC was defined and its relation to the buccal and lingual margin of the mandible was measured. Located at the lower part of the mandibular corpus, the MC runs in the form of an arch within the sagittal plane in anterior direction, getting enlarged into the form of an ampulla in the molar and premolar region. Whereas during the primary dentition the biggest size of the MC was found behind the third deciduous molar, during the secondary dentition the biggest size of the MC was seen in the region of the first and second permanent molar. With regard the buccolingual aspect, the central point of the MC was found mainly in the center of the mandibular corpus. Between the 2nd and 5th month as well as at the beginning of the 18th month the thickest canal wall existed on the buccal side. In the period of the eruption of the succedaneous teeth, however, the lingual wall was thicker than the buccal wall. Results suggest that the definite course of the MC achieves relatively early in the miniature pig with the completion of the primary dentition. There were no major changes of the position of the MC in the postnatal period suggesting that the age factor has only a minor effect on the location of the MC.