The effect of inferior alveolar neurotomy on mandibular growth in the rat.
To assess the role of possible growth alterations on the mandible, an investigation was undertaken to analyze the effect of bilateral sectioning the inferior alveolar nerve on mandibular growth in 21 day-old Charles River strain rats. The experimental group (n = 26) was subjected to bilateral resection of the inferior alveolar nerve, while 34 animals of comparative age were sham operated and served as controls. At 111 days maturity, the following alterations in the size and shape of the mandible were observed in the experimental animals: 1) the coronoid process in the experimental group was longer, slightly thinner and more curved, 2) antegonial notching was more pronounced. Mandibular length increased from 14 mm to 20.9 mm in control animals, while in the experimental animals, the length of the mandible was 19.6 mm. Thus, the length of the mandible in experimental group was 1.3 mm on the average shorter than the control group (p < 0.0001) and the difference between the two groups was highly statistically significant. The average 1.6 mm difference between the mandibular height of control and experimental animals indicated that the experimental mandibular ramus was approximately 0.5 mm shorter than in control animals. The difference in ramus height between the groups was statistically significant (p < 0.003), but the difference in intercondylar width between control and experimental groups (p < 0.31) was not statistically significant. The corpus height between control and experimental groups was statistically significant (p < 0.0001). Incisor overjet increased from 1.3 mm in control group to 3.2 mm in experimental group (p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)
Ghassemi-Tary
B
B
Tufts University School of Dental Medicine, Boston, Massachusetts.
Cua-Benward
G B
GB
D000818:Animals; D003714:Denervation; D008334:Mandible / Q000254:growth & development* / Q000294:innervation*; D008340:Mandibular Nerve / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains