Effects of an intravenous infusion of Ringer's solution on eruption rates of incisor teeth in anesthetized rats.

Objective: The vasculature within the socket is reportedly involved in determining the position of continuously erupting teeth. Thus, loss of body fluid in anesthetized rats, which would affect the vascular physiology, should influence tooth movement. We investigated the effects of an infusion of Ringer's solution on the systemic arterial blood pressure, regional blood flow at the base of the incisor, and axial tooth movement in anesthetized rats to determine the cause of tooth displacement.

Effects of local injections of vasoactive drugs on eruption rate of incisor teeth in anaesthetized rats.

Objectives: Previous studies have suggested that the vasculature in the dental pulp and periodontal tissues plays an important role in producing the eruptive force in continuously erupting incisors. The aim of the present study was to investigate the effects of local injections of vasoactive drugs on regional blood flow within the socket in association with axial tooth movements to clarify the role of the local vascular system on tooth eruption.

Design: Twenty-two male Wistar rats, weighing 309+/-21 g (S.

Restoration of mechanical strength and morphological features of the periodontal ligament following orthodontic retention in the rat mandibular first molar.

Biomechanical properties and morphological features of the periodontal ligament (PDL) in the rat mandibular molars were examined during orthodontic retention. Seventy-three male rats of the Wistar strain, 8 weeks of age, were used for biomechanical analysis and six rats for morphological analysis. An elastic band was inserted between the mandibular first and second molars for 4 days; after removal of the elastic band the interdental space was filled with resin for 4 and 8 days.

Polarized light microscopic analyses of collagen fibers in the rat incisor periodontal ligament in relation to areas, regions, and ages.

We prepared decalcified sagittal sections (20 microm thick) from the incisal, middle, and basal regions of the mandibular incisor of male Wistar rats aged 2, 6, 12, and 24 months, and examined the sections using polarized light microscopy. Most of the birefringent fibers appeared to run obliquely across the periodontal ligament. Birefringent fibers running parallel to the long axis of the incisor were also found in the intermediate area of the ligament.