Observations on the Microcirculation in the Gingiva of Hamsters and Other Laboratory Animals

Abstract

By using the teeth for immobilisation and employing incident light microscopy at magnifications up to 240x, entire capillary beds could be observed in the labial gingiva in small laboratory animals. In the mandibular incisor region, simple capillary loops, as found in the human gingiva and nail bed, were absent in all species examined except in some guinea pigs. In the hamster, where the topography of the gingival capillary bed was studied in greatest detail, blood flow was regulated by changes in caliber of arterioles; by opening and closing of exits from main capillary channels into networks apparently devoid of vasomotor activity; and by opening and closing of arteriovenous anastomoses. Under certain conditions, settling of blood cells and blood cell clumps to the lower side of gingival veins, together with gravitationally layered flow, was observed.

The organisation of the gingival vasculature

“…In the past, identification of vessels in a gingival vasculature has been mainly based on results from one technique (Staple & Copley 1959, Kindlova & Matena 1962, Castelli & Dempster 1965, Kindlova 1965, Kindlova & Trnkova 1972. The current study indicates that a combination of vital microscopy, perfusion and histological techniques facilitates the identification of the types of vessel present, their spatial orientation and their morphology.…”

Changes in gingival blood flow during orthodontic treatment

“…So a noninvasive and continuous technique was needed for measurement of gingival blood flow in human subjects. Studies on the changes in gingival blood flow due to gingivitis or changes in pulp circulation were published earlier [13][14][15][16][17]. In these studies many factors were measured: the effects of temperature, pressure, occlusal force, inflammation, administration of local anaesthetic containing vasoconstrictor and sympathetic stimulant agents.…”

“…In dental diagnostics a further advantage of LDF is that blood flow can be measured not only in directly accessible soft tissues (e.g. : gingiva), but in dental pulp as well, in permanent and primary, unharmed and traumatized teeth also, and in healthy and cleft palate patients as well [7,[12][13][14][15][16][17][21][22][23][24][25]. There are also data on changes in the blood flow of oral tissues of orthodontic patients.…”

The blood vessels of the dento‐gingival junction

“…Previous investigations concet-ning the arrangement of blood vessels iti the gingiva have been principally concerned with the capillaiy loops situated itnmediately deep to the oral epithelium. These vessels have been studied by means of vital mict-oscopy (see review by Forsslund 1959, and recent studies by Staple and Copley 1959, Wakano 1961, Ftanke 1964a, 1964b, Kamijo et al 1964. India ink perfusion (Keller and Cohen 1955, Goldman 1956, Castelli and Dempster 1965 and latex casts (Kindlova and Matena 1959, Kindlova 1965a, 1965b have also been used to study various aspects ofthe periodontal vasculature.…”