An analysis of the effect of tooth intrusion on the microvascular bed and fenestrae in the apical periodontal ligament of the rat molar.
An analysis of the rat apical periodontal ligament (PDL) microvascular bed and fenestrae was conducted to evaluate the effect of a continuous 1.0 N intrusive tooth load for 30 minutes. The microvascular bed consisted of postcapillary-sized venules, venous and arterial capillaries, and terminal arterioles. Intrusion produced significant increases (p less than 0.01) in vascular volume for postcapillary-sized venules and venous capillaries in three of the four animals. Arterial capillaries, overall, showed a statistically significant increase (p less than 0.01). The endothelial surface area (micron2 x 10(6)) per cubic millimeter of PDL responded variably in postcapillary-sized venules and venous capillaries but showed a strong trend to increase in arterial capillaries. After tooth intrusion a significant reduction (p less than 0.01) occurred in the number of fenestrae per square micrometer of endothelium in postcapillary-sized venules and venous capillaries. Fenestrae in the control PDL had a mean diameter of 51.5 nm +/- 0.6 (SE), whereas those on the intrusion side were smaller (p less than 0.05), measuring 49.9 nm +/- 0.4 (SE).
Clark
A B
AB
Department of Dentistry, University of Adelaide, Australia.
Sims
M R
MR
Leppard
P I
PI
D000818:Animals; D001160:Arterioles / Q000033:anatomy & histology / Q000502:physiology; D001810:Blood Volume; D002196:Capillaries / Q000033:anatomy & histology / Q000502:physiology / Q000648:ultrastructure; D002199:Capillary Permeability; D003799:Dental Stress Analysis; D004730:Endothelium, Vascular / Q000033:anatomy & histology*; D008297:Male; D008833:Microcirculation; D008963:Molar; D010513:Periodontal Ligament / Q000098:blood supply*; D051381:Rats; D014092:Tooth Root / Q000098:blood supply; D014651:Vasa Vasorum / Q000033:anatomy & histology; D014699:Venules / Q000033:anatomy & histology / Q000502:physiology