THE BIOLOGY OF TOOTH MOVEMENT

THE BIOLOGY OF TOOTH MOVEMENTBYQIRA ZIA, M SHARIQ, TOOBA QAISAR, ANUM ZAIDI, HALIMA CHAKRANI.

PRESENTATION OUTLINE 1)Introduction to orthodontic tooth movement.2)Periodontal and bone response to normal function.3)Theories of tooth movement.4)Phases of tooth movement.5)Types of orthodontic forces.6)Types of orthodontic tooth movement.7)Definitions.8)Deleterious effects of orthodontic forces.9)Methods of enhancement orthodontic tooth movement.

INTRODUCTION TO ORTHODONTIC TOOTH MOVEMENT ORTHODONTIC TOOTH MOVEMENT:It is a biological response to interference in the physiological equilibirium of the dentofacial complex by an externally applied force.

STIMULUS: Force applied to teeth for purpose of causing tooth movement.

OPTIMUM ORTHODONTIC FORCE: 1)Produces rapid tooth movement 2)minimal patient discomfort 3)The lag phase is minimum 4)No marked mobility should be seen. 5)The vitality of PDL and other structures should be maintained 6)Initiates maximum cellular response. 7)Produces frontal resorption.

Orthodontic force mild24/7 ; orthopeadic forcehigh magnitude 12-16 hours.

Optimal orthodontic forcemechanical input= maximum rate of tooth movement and minimal irreversible tissue damage.

Optimum orthodonti force: Produces rapid tooth movement, minimal pateint discomfort, the lag phase is minimum, no marked mobiltiy of teeth should be there histo : the vitality of pdl and other strcutures is maintained, initiates maximum cellular response, produces direct or frontal resorption

levelling, space closure/molar correction,finishing

Metabolic activity in PDL: Formation, cross linkage, and maturation shortening of collagen fibers3

PERIODONTAL AND BONE RESPONSE TO NORMAL FUNCTION 1)Normal periodontal ligament space 0.25- 0.5mm

2)Component of PDL includes . a)PDL fibers(resists the diplacement of tooth) b)The cellular elements( fibroblasts and osteoblasts) C)The tissue fluids.

3)Tooth movement during mastication: a)