INTRODUCTION:

Periodontal disease does not directly affect the occluding surfaces of teeth, consequently some may find a section on periodontics a surprising inclusion. Trauma from the occlusion has been linked with periodontal disease for many years. Occlusal trauma has been defined as injury to the periodontium resulting from occlusal forces that exceeds the reparative capacity of the attachment apparatus. According to WHO, it is defined as damage in the periodontium caused by stress on teeth produced by teeth in the opposite jaw (1). An occlusion that produces such injury is called a traumatic occlusion. Over the years, there have been a number of human and animal studies investigating this relationship. Traumas from occlusion results when the pressures surpasses the tolerance threshold of periodontium.Excessive occlusal forces may result in radiographic changes, including widening of the periodontal ligament space, especially at the alveolar crest, alteration in furcation bone quality, and variations in the appearance of the lamina dura.

There are various types of occlusal forces, normal physiological forces, impact force, continuous forces and jiggling forces.

Normal Physiological forces : Forces exerted on teeth during swallowing and chewing. These forces are small in magnitude and do not exceed more than 5 Newton.

Impact forces : These are forces with short duration and high magnitude. When the forces screed beyond the viscoelastic property of periodontium, there is occurrence of occlusal traumas.

Continuous force : Low magnitude forces, generated for a long period of time, like in orthodontic treatments.

Jiggling forces : Intermittent forces on teeth in multiple directionas in case of premature contacts. (2)

Acute trauma from occlusion:

Results from an abrupt occlusal impact on bitten objects, restorations or prosthetic appliances that interfere with or alter the occlusal forces on teeth. It exhibits symptoms like tooth pain, sensitivity to percussion and increased tooth mobility. If left un treated may cause necrosis in tooth supporting structures, abscess formation and cement all tears due to high occlusal forces

Chronic trauma from occlusion:

Results due to tooth wear, parafunctional habits like bruxism and clenching,restorations and tooth movements. It has greater significance and more commonly clinically observed. Clinically seen as tooth wear, tooth migration and extrusion. With time pathological changes are seen (3).

Traumas due to occlusion are also divided as Primary, secondary and combined occlusal traumas.

Primary Occlusal Trauma:

Injury resulting from excessive occlusal forces applied to a tooth or teeth with normal support eg. high restorations, bruxism, drifting or extrusion into edentulous spaces, and orthodontic movement. Does not impact connective tissues and does not initiate pocket formations. The associated forces can be divided according to duration, frequency and magnitude.

Secondary Occlusal Trauma:

Injury resulting from normal occlusal forces applied to a tooth or teeth with inadequate support (4).

Combined Occlusal Trauma:

Injury from an excessive occlusal force on a diseased periodontium e.g. gingival inflammation with some pocket formation, and the excessive occlusal forces are generally from parafunctional movements (5).

PRE DISPOSING FACTORS:

Teeth are constantly subject to both horizontal and vertical occlusal forces. With the center of rotation of the tooth acting as a fulcrum, the surface of bone adjacent to the pressured side of the tooth will undergo resorption and disappear, while the surface of bone adjacent to the tensioned side of the tooth will undergo apposition and increase in volume (6).

There are various causative and predisposing factors divided as extrinsic and intrinsic factors.

Intrinsic Factors :

1) Orientation of long axis of tooth to which they are exposed.

2) Morphology of tooth like shape, size and number of roots. Short conical, slender or fused roots are more prone to traumas.

3) Alveolar process, the quantity and quality of bone present also influences probabilities of traumas.

Extrinsic factors :

1) Fabrication of long span bridges.

2) Plaque accumulation.

3) Injurious bone resection.

4) Parafuntional habits like clenching and bruxism.

5) Food Impaction.

6) Over hanging fillings.

7) Poor fitting crowns.

8) Ill fitting dentures (7).

The precipitating factors include magnitude of force, duration of force, direction forces and frequency of force application.

EXAMINATION:

Increased tooth mobility is not always indicative of trauma from occlusion. It is important, however, that hypermobility which does occur as a result of trauma from occlusion is detected in patients with reduced periodontal attachment. The reason for this is that trauma from occlusion may accelerate further reduction in attachment in a patient with active periodontitis.A clinical diagnosis of occlusal trauma can only be confirmed where progressivemobility can be identified through a series of repeated measurements over an extended period. This means that simple but reliable monitoring needs to be undertaken. A simple monitoring protocol is needed. When evaluating a patient suspected of having occlusal trauma there are a number of clinical and radiographic symptoms that may be present. These indicators of trauma from occlusion may include one or more of the following (8,9).

Signs:

1) Tooth pain

2) Tooth migration – loss of inter proximal contacts.

3) Tooth mobility – one of the earliest symptomoccurring, due to widening of PDL. However may occur independently due to bone loss also. Progressive mobility suggest on-going occlusal trauma. Degree of mobility classified according to millers classification.

4) Widening of PDL, disruption of Lamina dura leading to condensation of alveolar bone.

5) Abfraction – specifically in premolars, appear before gingival recession.

6) Wear factors wear surface in area of interference can be seen. Most common cause is bruxism.

7) Tenderness in masticatory muscles.

8) Chipped crown, enamel.

9) Increased width of PDL.

10) Root resorption. (3).

Symptoms.

1) Persistant discomfort in eating

2) Thermal sensitivity

3) Muscle hypertonicity.

TISSUE RESPONSE TO TRAUMA:

The tissue injury occurs in three stagei.e. injury, repair and adaptive remodelling of the periodontium. Tissue injury is produced by excessive occlusal forces. Nature attempts to repair the injury and restore the periodontium. This can occur if the forces are diminished or if the tooth drifts away from them. When bone is resorbed by excessive occlusal forces, the body attempts to reinforce the thinned bony trabecular with new bone. This attempt to compensate for the lost bone is called ‘Buttressing Bone Formation.’ When this occurs within the jaw, it is called ‘Central Buttressing,’ wherein the endosteal cells deposit the new bone, which restores the bony trabecular and reduces the size of the marrow spaces. ‘Peripheral Buttressing’occurs on the facial and lingual surfaces of the alveolar plate. Depending on the severity, peripheral buttressing may produce shelf like thickening of the alveolar margin, called as ‘Lipping’ or a pronounced bulge in the contour of the facial and lingual bone. If the offending force is chronic, the periodontium is remodelled to cushion its impact. The ligament is widened at the expense of bone, angular bone defects occur without periodontal pockets and the tooth becomes loose (10).

TREATMENT :

A goal of periodontal therapy in the treatment of occlusal traumatism should be to maintain the periodontium in comfort and function. In order to achieve this goal a number of treatment considerations must be considered including one or more of the following.

1) Occlusal adjustment

2) Management of parafunctional habit

3) Temporary, provisional or long-term stabilization of mobile teeth with removable or fixe d appliances

4) Orthodontic tooth movement

5) Occlusal reconstruction.

6) Extraction of selected teeth (11).

Occlusal Adjustment:

Reshaping of crown or coronoplasty is shaping and grinding on teeth to correction occlusion and achieve proposer jaw relation. It is done to reduce traumatic forces to teeth exhibiting high mobility, to achieve functional efficacy and jaw relation. It is also indicated as an adjuvant therapy to reduce para functional habits. It is indicated for reshaping of teeth contributing to soft tissue injury and to adjust marginal relationships. Occlusal adjustment without careful pretreatment study, documentation, and patient education in contraindicated. Itscontraindications are, Prophylactic adjustment without evidence of the signs and symptoms of occlusal trauma, as the primary treatment of microbial-induced inflammatory periodontal disease and in treatment of bruxism based on a patient history without evidence of damage, pathosis, or pain. Instances of severe extrusion, mobility or malpositioning of teeth that would not respond to occlusal adjustment alone.

Management of para functional habits.:

Habits like bruxism cause excessive forces on the periodontium leading to its injury. The correct diagnosis of bruxism should be made by taking history of the patient and associated clinical findings. There are several short-term modalities by which the patient with bruxism can be treated- the behavioral modality, behavioral therapies such as electromyographic (EMG) biofeedback may be prescribed abrief course of physical therapy, medications prescribed for a few days aimed at altering sleep arousal or anxiety level and the maxillary stabilization appliance which remains the most universal and effective long-term means of interfering with the effects of bruxism(12,13).

Splinting:

Mechanism of joining teeth together to reduce Mobility and convert them into a single unit capable of bearing occlusal forces. Indication for splinting include, increasing mobility that have not responded to occlusal adjustment and periodontal treatment, tteth with advanced mobility that have not responded to occlusal adjustment and treatment when there is interference with normal function and patient comfort. To facilitate treatment of extremely mobile teeth by splinting them prior to periodontal instrumentation and occlusal adjustment procedures, prevent tipping or drifting of teeth and extrusion of unopposed teeth and also tostabilize teeth, when indicated, following orthodontic movement. Splint teeth so that a root can be removed and the crown retained in its place and stabilize teeth following acute trauma (14). However it is also contraindicated in various situations like when the treatment of inflammatory periodontal disease has not been addressed, when occlusal adjustment to reduce trauma and /or interferences has not been previously addressed and when the sole objective of splinting is to reduce tooth mobility following the removal of the splint.

Orthodontic tooth movement:

A periodontally compromised tooth with little bone support is not a good candidate for orthodontic tooth movement. Moving the tooth in a position which will further compromise its stability and long term prognosis is also not desirable. Tooth movement which eliminates abnormal occlusal forces as well as improves its long term prognosis, should be the primary goal during application of orthodontic forces on the tooth.

Occlusal reconstruction:

It is the redesigning of the complete occlusal scheme. It is done in cases where, by no other means occlusal equilibration can be achieved. It involves redesigning the occlusal contacts by giving crowns, bridges or implant-supported prosthesis.

Extraction of selected teeth:

In certain situations extraction of selected tooth/teeth may be done, such as a tooth with extensive periodontal involvement, having a poor prognosis and extraction of teeth which may improve prognosis of the remaining teeth. During orthodontic treatment also, extraction of certain teeth may be indicated for proper final positioning and alignment.

CONCLUSION:

While the role of occlusion in the progression of periodontal disease has been discussed and studied for over 100 years it has been and remains a controversial subject. There is no scientific evidence to show that trauma from occlusion causes gingivitis or periodontitis or accelerates the progression of gingivitis to periodontitis.The periodontal ligament physiologically adapts to increased occlusal loading by resorption of the alveolar crestal bone resulting in increased tooth mobility. This is occlusal trauma and is reversible if the occlusal force is reduced.Occlusal trauma may be a co-factor which can increase the rate of progression of an existing periodontal disease.Plaque is the primary causal factor in periodontal disease and it is believed its control should be a priority in any periodontal treatment (15).Occlusal forces may be a cofactor in the progression of periodontal disease. Treatment of occlusal discrepancies may be a beneficial adjunct to routine periodontal therapy. Plaque control and proper oral hygiene are the primary factors which focus on elimination of inflammation from the periodontal tissues. Elimination of the abnormal occlusal forces along with stabilisation of the involved tooth/teeth is the primary treatment for trauma from occlusion.

REFERENCES:

1. The American Academy of Periodontology. Glossary of Periodontal Terms, Chicago: The American Academy of Periodontology; 1992.

2. Bowers GM, Periodontics Syllabus. Washington DC: Dental Division, Bureau of Medicine and Surgery, Navy Department; 1975. NAVMED P-5110.

3. Glickman I, Smulow JB. Effect of excessive occlusal forces upon the pathway of gingival inflammation in humans. J Periodontol. 1965;36:141–7.

4. Loe H, Anerud A, Boysen H. The natural history of periodontal disease in man: prevalence, severity, and extent of gingival recession. J Periodontol. 1992;63(6):489–95.

5. Lawrence JJ, Periodontics Syllabus. Washington DC: Dental Division, Bureau of Medicine and Surgery, Navy Department; 1975.

6. Carranza, FA; Bernard, GW: The Tooth-Supporting Structures,Carranza’s Clinical Periodontology, 9th Edition. 2002

7. Box HK. Traumatic occlusion and traumatogenic occlusion. Oral health. 1930;20:642–6.

8. Hallmon WW. Occlusal trauma: effect and impact on the periodontium. Ann Periodontal 1999 Dec;4(1):102-8.

9. Parameter on occlusal traumatism in patients with chronic periodontitis. Parameters of Care. J Periodontol 2000 May

10. Dr. Rizwan M. Sanadi, Role of trauma from occlusion in periodontal disease- A controversy, IOSR Journal of Dental and Medical Sciences,15(9) (September. 2016

11. Parameter on occlusal traumatism in patients with chronic periodontitis. Parameters of Care. J Periodontol 2000 May.

12. Pertes R, Vella M, Milone A. Vertical skeletal facial types and condylar position in TMJ patients. J Dent Res 1989; 68:195.

13. Rugh JD, Solberg WK. Electromyographic evaluation of bruxist behaviour before and after treatment. Can Dent Assoc J 1975; 3:56.

14. Proceedings of the World Workshop in Clinical Periodontics. Chicago, American Academy of Periodontology, 1989.

15. Harell SK, Nunn ME, Hallmon WW. Is there an association between occlusion and periodontal destruction? J Am Dent Assoc 2006; 137:1380-92.  

Received on 30.01.2018 Modified on 26.03.2018

Research J. Pharm. and Tech 2018; 11(8): 3577-3580.

DOI: 10.5958/0974-360X.2018.00658.3