Effects Of Orthodontic Tooth Movement Research Articles

Periodontal tissue response to orthodontic movement of teeth with infrabony pockets

The aim of this study was to evaluate the effect of orthodontic tooth movement on the level of the connective tissue attachment in sites with infrabony pockets. The experiment was carried out in four beagle dogs. The second and fourth premolars were extracted. After healing, angular bony defects were prepared at the mesial aspect of the third premolars. The exposed root surface was scaled and planed, and a notch was prepared at the bottom of the defect. Plaque-collecting cotton floss ligatures were placed around the neck of the teeth and maintained in situ for 3 weeks, followed by an additional 2 months of plaque accumulation before the orthodontic tooth movement was initiated. In each dog, one premolar was moved away from the angular bony defect and one premolar into and through the angular bony defect. The maxillary third premolars served as control teeth and were not subjected to orthodontic tooth movement. After orthodontic treatment (5 to 6 months), the teeth were stabilized for a period of 2 months before biopsy sampling. Clinical, radiographic, and histologic evaluations revealed that it was possible to establish and maintain an infrabony pocket with a subcrestal, plaque-induced inflammatory lesion during the entire course of the study. While the control teeth had maintained their attachment levels, all but one of the orthodontically moved teeth showed additional loss of attachment.(ABSTRACT TRUNCATED AT 250 WORDS)

Histomorphometric study of dental pulp during orthodontic tooth movement

Orthodontic tooth movement has been implicated in secondary changes to the dental pulp. The purpose of this study was to correlate the effects of orthodontic tooth movement on the dental pulp by histomorphometric parameters. Four groups, each consisting of 36 male adult Sprague-Dawley strain rats, were studied with differing force magnitudes. These included a sham group in addition to groups with bilaterally placed appliances activated to 20, 40, and 60 g of initial force designed to mesially tip the maxillary first molars. Six rats were killed at 1, 3, 5, 7, 10, and 14 days. Specimens were fixed, embedded, and stained with tetrachrome. Pulpal measurements were made with an image analyzer and included changes in predentin and vascularity. Findings indicated a significant increase (p < or = 0.05) relative to time and force magnitude in capillary number. An initial pulpal hyperemia was observed following activation of orthodontic force which was unrelated to force magnitude. A force-dependent increase in predentin width was measured at the peak of the tooth movement cycle.

Effects of orthodontic tooth movement on the distribution of glycosaminoglycans of the alveolar bone of the rat: A histochemical study: R. H. Martinez and R. B. JohnsonUniversity of Manitoba, Faculty of Dentistry, Winnipeg, Manitoba, Canada

Effects of orthodontic tooth movement on the distribution of glycosaminoglycans of the alveolar bone of the rat: A histochemical study: R. H. Martinez and R. B. JohnsonUniversity of Manitoba, Faculty of Dentistry, Winnipeg, Manitoba, Canada

The effect of orthodontic forces on pulp respiration in the rat incisor

Maxillary central incisors of Sprague-Dawley rats were orthodontically stressed for 72 hours. Radiorespirometry was used to determine the effects of orthodontic tooth movement on the pulp tissue. Results indicated that orthodontic stresses produced a statistically significant increase in the pulp respiration rate.

Tissue changes involved in tooth movement

Maxillary central incisors of Sprague-Dawley rats were orthodontically stressed for 72 hours. Radiorespirometry was used to determine the effects of orthodontic tooth movement on the pulp tissue. Results indicated that orthodontic stresses produced a statistically significant increase in the pulp respiration rate.