Tooth Movement Flashcards
What is the correct way of applying forces for tooth movement?
Gentle and continuous
Applying continuous force to a tooth results in:
•Remodelling of Alveolar Bone
•Reorganisation of the PDL
•Changes in the Periodontium
What is the PDL made up of
•cells,blood vessels, collagen fibres
•Alveolar Bone
•Cementum
What is Alveolar bone capable of
•Remodelling
•Repair
•Regeneration
What are the two types of forces?
Light Forces - optimum
Heavy forces - Excessive
What are the two theories of tooth movement?
Piezoelectric Theory
Pressure Tension Theory
What is the Piezolelectric Theory
•Electric Signals
•Bone bending due to force
How is a Piezoelectric Current formed?
•Collagen fibres slip past each other
• helps regeneration and repair
• Collagen in Piezoelectric
What type of response is the Pressure/Tension Theory?
A chemical response
What is the Pressure/Tension Theory
•Alters blood flow by
-chemical messenger
-hormones
- cellular activity
What is the hormone released in the pressure/tension theory?
Prostagladin E
What do Heavy Forces create?
Undermining Resorption
What happens in the Tension side of the tooth?
• Bone is deposited
• Blood Increases
• Osteoblasts - deposit bone
What happens on the Pressure side of the tooth?
• Bone Resorbed
• Blood descreases
• Osteoclasts - Bone removed
What happens with Frontal Resorption?
• occurs with optimum force
• Front of the tooth
• Gradual Movement
• Bone remodelled
What happens with Undermining Resorption
•occurs with excessive force
•Necrosis
• Damage
• Dental Lamina gets attacked further down
•.Pain and teeth jumps after a few days
What are Osteoblasts?
New bone formation
What are Osteoclasts?
Resorb bone
What is Optimum force?
•Light Force
•Blood flows
• capillary pressure isn’t occluded
With Optimum Force, On the tension side what is found?
Osteoblasts
With Optimum Force, what is found on the pressure side?
Osteoclasts
What timeframe do Osteoclasts/ osteoblasts occur
48 hours
What happens when Excessive Force is applied?
•Occludes capillary pressure
• blood doesn’t flow
•cells die
What happens in the Periodontal ligament with Excessive force?
•Sterile necrosis and cell death occurs
•hyalinization
With Excessive Force what do the Osteoclasts do?
•Resorb the bone beneath area of Necrosis and adjacent to hyalinization
•happens few days after the force
What are Osteocytes?
• used to be osteoblasts
• change in mineralised bone
•detect mechanical load on the bone
How long is tooth movement delayed by in Excessive force?
7-14 days
What are Fibroblasts?
•They help remodel the PDL
•they remove old fibres and form bew fibers
• destroy old collagen fibres and produce new collagen fibres
What are cementoblasts?
•cells that form part of the cementum
•bone is deposited around the cementum
What are Cementoclasts?
•resorb necrotic tissue and cementum
• occur in undermining resorption
Clinical Sides of Frontal resorption?
• No prolonged discomfort for the patient
•Gradual movement of teeth
•no excessive mobility
Clinical signs of Undermining resorption?
•prolonged discomfort
•mobility
• delayed tooth movement and sudden jumps of movement
• Root resorption
What is Hyalinisation?
• Capillaries are occluded=
- necrosis and damage
