2 This series of slides is based on Lindhe et al This series of slides is based on Lindhe et al.’s textbook “Clinical Periodontology and Implant Dentistry”, chapter 8.
3 Definition Trauma from Occlusion: Pathologic or adaptive changes which develop in the periodontium as a result of undue force produced by the masticatory muscles.Stillman (1917): A condition where injury results to the supporting structures of the teeth by the act of bringing the jaws into a closed positionWHO (1978): Damage in the periodontium caused by stress on the teeth produced … by the teeth of the opposing jaw.AAP (1986): An injury to the attachment apparatus as a result of excessive occlusal force.
4 Definition Trauma from Occlusion Primary TfO: Secondary TfO: A tissue reaction, which is elicited around a tooth with normal height of the periodontium (no attachment loss!)Secondary TfO:Related to situations in which occlusal forces cause damage in a periodontium of reduced height (attachment loss present)
5 TfO and Plaque-Associated Periodontal Disease Karolyi’s (1901) HypothesisAn interaction exists between TfO and alveolar pyorrhea.Stones (1938)TfO is an etiologic factor in the production of that variety of periodontal disease in which there is vertical pocket formation associated with one or a varying number of teeth
6 Glickman’s ConceptPathway of spread of a plaque-associated gingival lesion can be changed if abnormally strong forces are acting on teeth with subgingival plaqueZone of irritation includes marginal and interproximal gingiva. Not affected by occlusal forces. Lesion propagates apically first by involving the bone then the periodontal ligament.
7 Glickman’s ConceptZone of co-destruction includes the ligament, cementum, bone, and the transseptal and dentoalveolar fibersFibers can be affected from the lesion in the zone of irritation, or from trauma-induced changes in the zone of co-destruction
8 Glickman’s ConceptIn teeth not affected by TfO, inflammatory lesion can spread into alveolar boneIn teeth affected by TFO, inflammatory lesion spreads into periodontal ligament. This will create an angular bony lesion combined with an infrabony pocket.
9 Glickman’s Concept Angular bony defect and infrabony pocket distal of premolar
10 Waerhaug’s ConceptApical cells of the JE and the subgingival plaque areat different levels. Crest of marginal bone is slanting.It follows the location of the JE and plaque.
11 Waerhaug’s ConceptWaerhaug measured distance between the subgingival plaque andThe perimeter of the associated inflammatory infiltrateThe surface of the adjacent alveolar boneHe concluded that angular defects and infrabony pockets occurred equally frequently in teeth with TfO and in teeth without TfOWaerhaug postulated that loss of attachment and bone are the result of inflammation induced by subgingival plaque
12 Orthodontic Movements T: tension zone P: pressure zoneRecession or AL can occur at sites of gingivitis when toothis moved through the envelope of the alveolar process.
13 Jiggling Forces 1: P-TfO Combined pressure and tension zones result from jigglingZones are characterized by collagen resorption, bone resorption, and cementum resorption.Signs of increased vascularity or exudation.Tooth shows progressive mobility.
14 Jiggling Forces 2 : P-TfO Ligament space gradually adjusts to new situation.No attachment loss!Increased tooth mobility
15 Jiggling Forces 3 : P-TfO Occlusal adjustment normalizes the width of the periodontal ligament.Teeth are stabilized and regain normal mobility.
16 Reduced Height, Healthy 1 : S-TfO Zones of combined pressure and tension exhibitvascular proliferation,exudation,thrombosis, andbone resorptionA widened periodontal ligament developsTooth mobility is increasing progressively
17 Reduced Height, Healthy 2 : S-TfO Ligament space gradually adjusts to new situation.No attachment loss!Increased tooth mobilityLigament tissue regains normal composition
18 Reduced Height, Healthy 3 : S-TfO Supra-alveolar tissue unaffectedNo further loss of attachmentTeeth hyper mobile, surrounded by tissue that adapted to the new functional situationOcclusal adjustment will allow the periodontal ligament to regain its normal width.
19 Reduced and Diseased 1 : S-TfO Can abnormal occlusal forces influence the spread of the plaque-associated periodontal lesion and/or enhance tissue breakdown?In the case presented here, there is a healthy zone between inflamed CT and PL
20 Reduced and Diseased 2 : S-TfO Pathologic and adaptive reactions occur in the PLA widened periodontal ligament and increased tooth mobility will resultNo further loss of attachment is observed
21 Reduced and Diseased 3 : S-TfO Occlusal adjustment will result in reduction of periodontal ligament width andReduced (not normal!) tooth mobility
22 Reduced and Diseased 4: S-TfO Presence of infrabony pocket and infiltrated connective tissueMerging of zones of “irritation” and “co-destruction”
23 Reduced and Diseased 5: S-TfO Jiggling forces lead to typical vascular and exudative reaction in ligament spacePathologic reaction may occur within a zone that also contains (plaque-induced) inflammatory cell infiltrate
24 Reduced and Diseased 6: S-TfO In this situation, increasing tooth mobility may also be associated with an enhanced loss of attachment and further down growth of the most apical portion of the PE
25 Reduced and Diseased 7: S-TfO Occlusal adjustment will result in narrowing of the ligament space, less tooth mobilityRegeneration of attachment cannot be expectedLoss of attachment is permanentIf plaque-induced inflammation persists, more attachment loss may occur
26 ConclusionsIn a healthy periodontium, neither unilateral nor jiggling forces can result in attachment loss or pocket formationTfO alone cannot induce periodontal tissue breakdownBone resorption in TfO should be interpreted as an adaptation of the ligament and bone to the altered functional requirementsIn plaque-induced inflammation, TfO may enhance the disease progression