Application of Continuous Light Force

In brief, when a continuous light force is applied to a tooth, a series of physiologic events occur which are later followed by metabolic and cell signalling events. The signalling recruits specialized cells and induce their differentiation to begin the process of orthodontic tooth movement.

Minutes:  Blood flow altered and oxygen tension begins to change. Prostaglandins and cytokines are released.

Hours: Metabolic changes occur. Chemical messengers affect cellular activity. Enzyme level changes.

4 Hours: Increased cyclic AMP (adenosine monophosphate; a cellular messenger molecule) levels are detectable & cellular differentiation begins within the periodontal ligament.

2 Days: Tooth movement begins as osteoclasts & osteoblasts remodel the bony socket.

Result of continuous Light Force

Continuous light forces do not occlude the periodontal ligament and allow for:

• Osteoclasts initiate resorption of lamina dura from the side of the periodontal ligament.
• The osteoclasts arrive in 2 waves.
• 1st wave is derived from the periodontal ligament itself.
• 2nd wave (larger) from distant areas via blood flow.
• All these events lead to FRONTAL RESORPTION.