Distraction osteogenesis: Clinical applications and biologic principles for orthodontics and dentofacial orthopaedics

Abstract

Dentofacial Distraction Osteogenesis is the gradual and incremental traction force/ tension to surgically separated bony segments of the stomatognathic system to produce additional bone with regeneration of attendant soft tissue. Distraction Osteogenesis/Histogenesis is a primary example of surgically induced tissue engineering. The distraction causes a cascade of biological factors to generate tissue (bone and soft tissue). It has become a substitute for current techniques of bone grafting and alloplastic materials in Dentofacial surgery. The principles of distraction osteogenesis can be simplified into 4 periods: 1. Creation of a distraction zone; 2. Latency period; 3. Activation period; 4. Consolidation period. The primary purpose of these principles is to shift the bony segment into the defect with regeneration of hard and soft tissues around the space of transported segment. There are 3 common types of distraction osteogenesis: unifocal, bifocal and trifocal depending upon number and direction of distraction devices employed and number of transport segments created. The process by which mechanical forces are converted to cellular signals is termed mechanical transduction. Through the conversion of mechanical (tension stress) signals to biological cascades, the DH method can activate a number of regulatory processes and restart the vigorous regenerating capacity of musculoskeletal tissues. The molecular mechanisms of DH are still expanding as a result of new technologies like next-generation sequencing, proteomics, and metabolomics, despite the fact that, any research have concentrated on them and the surgical concepts of DH have been better defined and perfected. This article explores types, histological stages, cellular and molecular mechanisms & indications.