Traumatic Occlusal Forces Flashcards
What conditions affect the periodontium?
- systemic disease
- periodontal abscess or periodontal/endodontic lesion
- mucogingival deformities and conditions
- traumatic occlusal forces
- tooth and prosthesis related factors
What is the etiology of occlusal trauma (OT)?
Injury resulting in tissue changes within the attachment apparatus (periodontal ligament, cementum and supporting bone) as a result of occlusal forces
What type of periodontium can occlusal trauma (OT) occur in?
May occur in an intact periodontium or in a reduced periodontium affected by periodontal disease
cannot happen in a patient without teeth
What is a reduced periodontium?
- reduced is loss of >60% of bone support
- any attachment loss = reduced periodontium
definition is a little confusing
Over 100s of years of studies on many types of animals it was discovered that occlusal trauma does or does not have an effect on pocket formation or loss of connective tissue?
DOES NOT
What are the parts of the periodontium affected by occlusal forces?
- Cementum
- PDL
- Alveolar Bone Proper
The gingiva and junctional epithelium are or are not affected by occlusal forces
are not
What are the classifications of traumatic occlusal forces on the periodontium (2017)?
A. Primary occlusal trauma
B. Secondary occlusal trauma
C. Orthodontic forces
What are the variables of occlusal trauma?
- Direction of force
- Magnitude of force
- Duration of force
- Frequency of occurrence
Trauma from occlusion is considered to be…
pathologic
Trauma from occlusion happens when forces of occlusion ________ the adaptive capacity of the periodontium
exceed
Is hyperfunction (high occlusion) pathologic, normal, or physiological?
moving towards pathologic
Is hypofunction (tooth not in occlusion) pathologic, normal, or physiological?
moving towards physiological
Is disues/atrophy pathologic, normal, or physiological?
physiological
A tooth opposing an implant will likely experience…
hypofunction
A tooth opposing a high restoration will likely experience…
hyperfunction
What are examples primary occlusal trauma?
- With Primary occlusal trauma, clinically may see adaptive mobility (does not progress)
- Example is ‘high’ restoration with mobility resolving following reduction
What is primary occlusal trauma?
Traumatic occlusal forces applied to a tooth or teeth with normal periodontal support
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 are the signs/symptoms of secondary occlusal trauma?
May be seen as progressive mobility &/or pain
What happens on the compression side of a tooth moving?
area that the teeth is moving toward
- PDL space is reduced as fibers are compressed
- Loss of fiber orientation
- Increased capillary permeability, rupture of blood vessels and hemorrhage into PDL perivascular spaces (edema)
- Resorption of alveolar bone proper (root resorption if severe) then widening of PDL space
What are the symptoms of minor trauma from occlusion?
- Increased capillary permeability, dilation
- Edema, disturbed fluid exchange
- Vascular damage with stasis, clotting, thrombosis
- Lowered periodontal resistance?
- Accompanying tissue effects, usually minor
What happens on the tension side of a tooth moving?
area that the teeth is moving from
- 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 (If severe, cemental tears)
What are the symptoms of severe trauma from occlusion?
- Crushing (pressure) injury - necrosis at furca, alveolar crest
- Extravasated RBCs, hematoma, necrosis, vascular damage
- 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 of primary occlusal trauma?
Traumatic occlusal forces applied to tooth or teeth with NORMAL periodontal support
What is the manifestation of primary occlusal trauma?
Adaptive mobility (not progressive or pathologic)
What is the definition of secondary occlusal trauma?
Normal or traumatic occlusal forces applied to a tooth or teeth with reduced periodontal support
What is the manifestation of secondary occlusal trauma?
- 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
- Radiographic
What is fremitus?
palpable or visible movement of a tooth when subject to occlusal forces
What are the clinical/radiographic indicators of occlusal trauma?
- Fremitus
- Mobility
- Occlusal discrepancies (working &/or balancing interferences)
- Wear facets
- Tooth migration
- Fractured tooth
- Thermal sensitivity
- Discomfort/pain on chewing
- Root resorption
- Widened periodontal ligament space
- Cemental tear
What are the clinical signs/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 is the mobility index?
- 1 = first distinguishable sign of movement > than normal (physiologic)
- 2 = movement which allows crown to move 1 mm from its normal position in any direction
- 3 = tooth may be rotated or depressed in alveoli
How do you test mobility?
use 2 rigid instrument handles (not fingers)
What are 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
What suggests occlusal discrepancy?
- Working &/or balancing interferences
- Wear facets (BUT may be normal part of aging!)
What is bruxism?
Grinding, clenching or clamping of the teeth.
* The force may damage tooth or attachment apparatus
What are the signs/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 some other manifestations of traumatic occlusal forces?
- 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 &/or condensation
PDL thickest at apices & alveolar crest at ______ mm
0.20
PDL is less thick at the midroot (about _____ mm) than the apice
0.15 mm
What are the dimensions of the PDL
- apices & alveolar crest (0.20 mm)
- mid-root (0.15 mm)
Existing loss of __________ may contribute to mobility
attachment
Wear facets may be due to ________ function rather than parafunctional habits (bruxism, clenching, grinding)
‘normal’
What are the indications for occlusal adjustment?
- Traumatic injuries / soft tissue injury; food impaction
- Increasing mobility or fremitus
- Parafunctional habits
- In conjunction 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 outcome of periodontal therapy and maintenance
- Tooth mobility generally will decrease once inflammation is controlled
What do you need to solve first before occlusal adjustments?
inflammation
- scaling and root planing, remove the plaque
Occlusal trauma does or does not initiated periodontal disease
important
DOES NOT
What are the recommendations for treating secondary occlusal trauma?
- If see signs and symptoms of occlusal trauma and patient’s 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 trauma ‘may slow the progression of periodontitis and improve the prognosis’
True/false
teeth with a reduced but healthy periodontium (no inflammation) may undergo successful tooth movement without compromising periodontal support
True
What is occlusal hyperfunction?
- Slight increase in occlusal force.
- Considered to be a physiologic adaptation and not a pathologic entity
What are the 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
What are the symptoms 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 physiologic stimulation required to maintain normal form and function
What are the symptoms of disuse atrophy?
- Radiographic evidence of decreased width of PDL space.
- Increased tooth mobility is always present.
- Absence of occlusal antagonist.
- Loss of orientation of the principle fiber bundles of the PDL.
- Narrowed PDL width.
- Significant decrease in number of bony trabeculae, i.e., localized osteoporosis.
Trauma from occlusion, in the absence of inflammation, does not cause:
- gingivitis
- periodontitis
- pocket formation
How do you do mutually protected occlusion?
- Anterior guidance
- Wide freedom in centric relation (decrease cuspal inclines)
- Reduce occlusal overload (more implants, less cantilevers)
- Close monitoring for parafunctional habits
Traumatic occlusal forces have _________________ of causing periodontal attachment loss in humans
No evidence
True/false
An implant can move and still be solid in bone
false
There is ____________ that traumatic occlusal forces causes non-carious cervical lesions (NCCLs)
important
no evidence
NCCLs may result from…
abrasion, erosion, or corrosion
EVIDENCE from observational studies that Traumatic Occlusal Force does or does not cause gingival recession
important
DOES NOT
True/false
There can be no evidence implicating abfraction as cause of recession
True