The Course of the Mandibular Canal in the Growing Miniature Pig

Abstract

Summary: 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 interdentsdly.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 regardthe baccolingual 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.The form of the mandible as well as its internal architecture are the result of complex interactions of genetic and epigenetic factors (Enlow and Harris, 1964;van Limborgh, 1983;Sarnat, 1986). Among the epigenetic factors, the function of the jaw musculature and the developing teeth have a considerable influence on the mandible's morphology (Schumacher, 1968;Daegling et aL, 1992;Hylander, 1992;Atchley, 1993;Herring, 1993; Fanghdnel and Miehe, 1994). Teeth and their supporting tissues are of special importance, e.g. for the distribution of masticatory stress applied to the mandible (Daegling et aL, 1992). An unloading of the mandible such as in case of tooth loss leads to the well known changes of the mandible such as resorption of the alveolar process (Gabriel, 1958;Schumacher, 1991), changes of the external dimensions of the mandible (Morita et aL , 1993), reduction of the cortical bone mass (Klemetti et aL, 1993), and to an increase of the osteon number in the cortical bone (Matsuzaka, 1994).In comparison with the vast amount of literature on the growth pattern of the mandibles in humans and in different mammals, the k...

Effects of fibrin sealant protein concentrate with and without platelet‐released growth factors on bony healing of cortical mandibular defects

“…A drawback of our study was that the minipig mandible has a wide mandibular canal at the operative site (Koppe et al 1997). The bottom of the cavities was either bone marrow or the inferior lingual mandibular wall.…”

Refining experimental dental implant testing in the Göttingen Minipig using 3D computed tomography—A morphometric study of the mandibular canal

“…These were of 11 groups ranging from 3 days to 24 months. They found, that in contrast to the uniform diameter of the human mandibular canal that that of the minipig was enlarged in the molar and premolar regions [ 30 , 31 ]. Because the MINI-LEWE pigs are considerably larger than Göttingen Minipigs their morphological dimension cannot be compared readily with each other [ 32 ].…”