Physiologic timing of orthodontic treatment
Related Experiment Video
Updated: Aug 12, 2026

3D Imaging of PDL Collagen Fibers during Orthodontic Tooth Movement in Mandibular Murine Model
Published on: April 15, 2021
Abstract:
1. With the knowledge that certain facial bones respond in growth similarly to the growth of long bones, the hand-wrist film can be used as an indicator of the maturational status of the orthodontic patient. 2. Six stages of hand-wrist development have been advocated as guides in the timing of treatment with the stages geared to the individual patient rather than to statistical tables. 3. Stage 2 represented the important early prepubertal period when much growth was ignored but during which Class II correction could be effectively achieved without prolonged periods of mechanotherapy. 4. It was emphasized that the puberal growth spurt could be overlooked by the clinician. In addition, puberal spurt in the female may be of such a short duration that much growth may have already elapsed by the time this stage was recognized. 5. Stage 5 represented the period of residual growth during which posttreatment changes could occur. At the present state of the art these changes seem to be unpredictable but some warning may be possible with the use of the hand-wrist film taken prior to the termination of treatment. 6. The clinician is encouraged to utilize the hand-wrist film as another diagnostic aid. A few easily recognizable events can indicate the individual's maturational status.
Related Concept Videos
Fractures: Bone Repair
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the procedure...
Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
Tooth Anatomy
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...

