Traumatic Occlusal Forces Flashcards
what is occlusal trauma
injury resulting in tissue changes within the attachment apparatus (PDL, cementum, and supporting bone) as a result of occlusal forces
what are the occlusal forces
teeth
where may occlusal trauma occur
on an intact periodontium or in a reduced periodontium affected by periodontal disease
what is a reduced periodontium
based on an in vitro study, reduced is loss of greater than 60% of bone support
what are the parts of the periodontium affectde by occlusal forces
- cementum
- PDL
- alveolar bone proper
are the gingiva and JE affected by occlusal forces
no
what are the classes of traumatic occlusal forces. on the periodontium
- primary occlusal trauma
- secondary occlusal trauma
- orthodontic forces
is occlusal truma called excessive or traumatic
traumatic
what are the variables affecting occlusal trauma
- direction of force
- magnitude of force
- duration of force
- frequency of occurence
trauma from occlusion is considered to be:
pathologic
describe trauma from occlusion
forces of occlusion exceed the adaptive capacity of the periodontium
what are the types of occlusal wear that are considered physiological
- hypofunction
- disuse atrophy
what are the types of occlusal wear are considered pathological
- occlusal trauma
- hyperfunction
what is primary occlusal trauma
- traumatic occlusal forces applied to a tooth or teeth with normal periodontal support
what is seen with primary occlusal trauma
may see adaptive mobility - does not progress
what is an example of primary occlusal trauma
a high restoration with mobility resolving following reduction
what is secondary occlusal trauma
injury resulting in tissue changes from normal or traumatic occlusal forces applied to a tooth or teeth with reduced periodontal support
what may secondary occlusal trauma be seen as
progressive mobility and/or pain
what are the forces in primary occlusal trauma
- points of rotation of tooth with horizontal force
- results from trauma from occlusion from non-vertical forces
- traumatic force on a normal system
what is seen with secondary occlusal trauma
reduced bone support
- normal or traumatic forces on reduced periodontal support
- results from normal or traumatic forces on a reduced periodontium
what happens from the compression from trauma from occlusion
- PDL space is reduced as fibers are compressed
- loss of fiber orientation
- increased capillary permeability, rupture of blood vessels and hemorhage into PDL perivascular spaces (edema)
- resorption of alveolar bone proper (root resorption if severe) then widening of PDL space
what is happening on the tension side from trauma from occlusion
- increase in PDL space
- rupture of PDL fiber bundles
- compression of PDL blood vessels and hemorrhage into perivascular spaces
- deposition of new alveolar bone and decrease in PDL space
what is happening in severe trauma from occlusion
- crushing pressure injury - necrosis at furca, alveolar crest
- extravasated RBCs, hematoma, necrosis, vascular damage
describe what happens in severe trauma from occlusion
- well. defined necrosis, including PDL, cementum, bone
- degenerative changes ( hyaline, mucoid, liquefaction)
- repair from PDL, endosteal cells, bone marrow, Haversian systems (rear resorption)
what is the definition and manifestation of primary occlusal traum
- traumatic occlusal forces applied to tooth or teeth with normal periodontal support
- adaptive mobility- not progressive or pathologic
what is the definition and manifestation of secondary occlusal trauma
- normal or traumatic occlusal forces applied to a tooth or teeth with reduced periodontal support
- progressive mobility - may exhibit mobility and/or pain on function. consider splinting
the lesion of occlusal trauma can only be confirmed:
histologically by block section biopsy, so must use other surrogate indicators such as clinical and radiographic
what are the proposed clinical and radiographic indicators of occlusal trauma
- fremitus
- mobility
- occlusal discrepancies
- wear facets
- tooth migration
- fractured tooth
- thermal sensitivity
- discomfort/pain on chewing
- widened PDL space
- root resorption
- cemental tear
what is fremitus
a palpable or visible movement of a tooth when subjected to occlusal forces
what are the clinical signs and symptoms of occlusal trauma
- mobility of affected teeth
- radiographic evidence of thickened PDL
- positive hx of clenching or bruxism
- missing or tilted teeth
- evidence of working and/or balancing side occlusal interferences
what are the classes of mobility index
- 1: first distinguishable sign of movement greater than normal ( physiologic)
-2: movement which allows crown to move 1mm from its normal position in any direct - 3: tooth may be rotated or depressed in alveoli
how do you test mobility
using 2 rigid instruments
- not fingers
what are the occlusal discrepancies
- working and/or balancing interferences
- evidence of occlusal slide in CR or CO
- evidence of occlusal interferences in protrusive mandibular movement
- extremely steep cuspal inclines
- wear facets- but may be a normal part of aging
what is bruxism and what can it cause
- grinding, clenching, or clamping of the teeth
- the force may damage tooth or attachment apparatus
what are the signs and symptoms of bruxism
- increased mobility
- pulpal sensitivity/bite tenderness
- non- masticatory/ excessive occlusal wear
- dull percussion sound
- muscle tenderness/spasm/ hypertrophy/tiredness (am)
- TMJ pain/jawlock
- audible sounds
what are the other manifestations of traumatic occlusal force
- malocclusions
- tooth migration
- fractured teeth
what are the radiographic signs of occlusal trauma
- widened PDL space
- thickening of lamina dura
- vertical (angular) bone loss
- furcal bone loss
- alveolar radiolucency and/or condensation
what are the PDL dimensions
- PDL thickest at apices and alveolar crest ( 0.2 mm)
- less at mid root (0.15mm)- varies with functional/force status of tooth
what are the problems with surrogate indicators
- existing loss of attachment may contribute to mobility
- wear facets may be due to normal function rather than parafunctional habits ( bruxism, clenching, grinding)
- altered vitality of teeth may be due to other factors
what are the indications for occlusal adjustment
- traumatic injuries/soft tissue injury; food impaction
- increasing mobility or fremitus
- parafunctional habits
- in conjugation with orthodontic/orthognathic therapy
what are the contraindications to occlusal adjustment
- absence of a pre treatment diagnosis
- as prophylactic therapy or only treatment for periodontal disease
- as primary therapy of bruxism
- severe extrusion or malpositioned teeth
- when periodontal inflammation has not been controlled
what are the effects of periodontal treatment on mobility
- tooth mobility negatively affects outcomes of periodontal therapy and maintenance
- tooth mobility generally will decrease once inflammation is controlled
if signs and symptoms of occlusal trauma and patients comfort and function are impacted then:
- perform occlusal adjustment in conjunction with periodontal therapy
- evaluate and record occlusion before, during, and after treatment
- treatment of occlusal truama may slow the progression of periodontitis and improve the prognosis
what is occlusal hyperfunction
slight increase in occlusal force
occlusal hyperfunction is considered to be a ____ adaptation
physiologic
what are the clinical symptoms of occlusal hyperfunction
- increase in number and diameter of collagen fiber bundles in PDL
- increased width of PDL
- increased density and thickness of alveolar bone proper (lamina dura)
- radiographic evidence of osteosclerosis
- slight or undetectable tooth mobility
how can occlusal hypofunction be diagnosed
only by histology
describe the features of occlusal hypofunction
- decrease in number of PDL fiber bundles but normal orientation
- decreased physiologic turnover and remodeling of alveolar bone
- narrowing of PDL space
- no change in tooth mobility
what is disuse atrophy
total removal of occlusal forces resulting in lack of the level of physiological stimulation required to maintain normal form and function
disuse atrophy is considered _____ adaptation
physiologic
what are the clinical symptoms of disuse atrophy
- radiographic evidence of decreased width of PDL space
- increased tooth mobility is always present
- absence of occlusal antagonist
what are the features of disuse atrophy
- loss of orientation of the principle fiber bundles of the PDL
- narrowed PDL width
- significant decrease in number of bony trabeculae such as localized osteoporosis
trauma from occlusion in the absence of inflammation, does not cause:
- gingivitis
- periodontitis
- pocket formation
is there evidence that traumatic occlusal forces cause periodontal attachment loss in humans
no
is there evidence that traumatic occlusal forces cause inflammation in the periodontal ligament
limited evidence
are traumatic occlusal forces associated with severity of periodontitis
no
truamatic occlusal forces have a relationship with:
- non carious cerival lesions/abfraction
- recession
is there evidence that traumatic occlusal forces cause non carious servical lesions
no
non carious cervical lesions may result from:
abrasion, erosion, corrosion
does traumatic occlusal forces cause gingival recession
no
