Periodontal Considerations in Restorative Dentistry Flashcards
What is the function of the periodontium?
Attach teeth to the jaws
Dissipate occlusal forces
Determine biting force
What is excessive occlusal force?
Occlusal force that exceeds the reparative capacity of the periodontal attachment apparatus, which results in occlusal trauma and/or causes excessive toothwear.
What is occlusal trauma?
Describes injury resulting in tissue changes within the attachment apparatus, including periodontal ligament, supporting alveolar bone and cementum, as a result of occlusal force.
What factors influence tooth mobility?
Width of PDL
Height of PDL
Inflammation
Number, shape and length of roots
Describe how occlusal forces influence the PDL?
As occlusal force is applied to the tooth, there is tension within the PDL, due to the tooth being pushed down into the socket.
In areas of compression- the bone is resorbed.
In areas of tension- bone is deposited.
In teeth with bone loss, the same force is applied but the fulcrum around which the tooth rotates is much more apical compared to a tooth that does not have bone loss
- results in more movement of the crown.
Tooth mobility may be accepted, unless….?
Mobility is becoming progressively greater
It gives rise to symptoms
It creates difficulty with restorative treatment
What therapy can be done to reduce tooth mobility?
Splint
Control of plaque-induced inflammation
Correction of occlusal relations
What is primary occlusal trauma?
Injury resulting in tissue changes from excessive occlusal forces applied to a tooth or teeth with normal periodontal support.
Occurs in the presence of normal clinical attachment levels, normal bone levels and excessive occlusal forces.
How does the PDL respond to primary occlusal trauma?
PDL width increases until forces are adequately dissipated and the width then stabilises.
Tooth mobility will increase as a result.
If demand is reduced- PDL width will return to normal.
If demand of occlusal forces is too great or adaptive capacity of the PDL reduced- PDL may continue to increase.
PDL width and tooth mobility fail to reach a stable phase
- This failure of adaptation is pathological.
Describe the histological changes in the PDL after primary occlusal trauma?
On the pressure side of the PDL
- increased vascularisation and permeability, hyalinisation/necrosis of the PDL, bone resorption.
On the tension side of the PDL
- elongation of the PSL fibres and apposition of alveolar bone and cementum.
Due to sustained occlusal trauma- the density of alveolar bone decreases while the width of the PDL space increases
- leading to increased tooth mobility.
What is secondary occlusal trauma?
Injury resulting in tissue changes from normal or excessive occlusal forces applied to a tooth or teeth with reduced periodontal support.
It occurs in the presence of attachment loss, bone loss and normal excessive occlusal forces.
What signs and symptoms would suggest occlusal trauma?
Progressive tooth mobility- that is increasing
Fremitus- palpable or visible movement of a tooth when subjected to occlusal forces.
Occlusal discrepancies/disharmonies
Wear facets
Tooth migration
Tooth fracture
Thermal sensitivity
Root resorption
Cemental tear
Widening of the PDL space on radiographic examination
How would you manage tooth migration caused by dental trauma?
Treat periodontitis
Correct occlusal relations
Either
- Accept position of the teeth and stabilise or move the teeth orthodontically and stabilise.
What is the effect of occlusal trauma on periodontal therapy?
Decreased CAL gain post HPT.
Increased CAL over time
Mobile teeth treated with regeneration do not respond as well as non-mobile teeth
Teeth with occlusal discrepancies have……
Deeper initial probing depths
More mobility
Poorer prognosis than those teeth without occlusal discrepancies
