Occlusal Analysis and Adjustment

Occlusal Analysis and Adjustment

• Occlusion is defined as the static relationship between the incisal or occlusal surfaces of maxillary or mandibular teeth or their analogues.
• An ideal occlusion should be balanced and as stress-free as possible.
• Occlusal forces can cause displacement of the tooth root in the socket resulting in injury to the supporting periodontal ligament.
• This injury is considered a traumatic lesion from occlusion.
• Microscopic changes resulting from occlusal forces include increased vascularization, vascular permeability, vascular thrombosis, and disruption of fibroblasts and collagen fiber bundles.
• Prolonged occlusal force leads to osteoclast appearance on the alveolar surface, resulting in net bone resorption.
• Teeth and their periodontium are subjected to dynamic loading during chewing, swallowing, and parafunctional habits such as bruxism and clenching.
• Tooth contact during speech is minimal.

Definitions

• Occlusion is the static relationship between the incising or occlusal surfaces of maxillary or mandibular teeth or tooth analogues.
• Occlusion should be balanced and as stress-free as possible.

Occlusion Types

• Physiologic occlusion occurs when no signs of dysfunction or disease are present, requiring no treatment.
• Non-physiologic/traumatic occlusion is when dysfunction or disease is caused by tissue injury, often requiring treatment.
• Therapeutic occlusion is the result of specific interventions to treat dysfunction or disease.

Clinical Examination

• A thorough evaluation of the masticatory system (muscles and occlusal anatomy) is essential to identify occlusal disharmonies.
• Clinical assessments include: Temporomandibular joint (TMJ) evaluation, checking teeth mobility, assessing centric relation, evaluating excursions, and examining articulated diagnostic casts.

Evaluations

• Temporomandibular disorder screening evaluation includes maximal opening (range of 40-50mm), opening/closing pathway, range of lateral and protrusive excursions (≥7mm to 9mm), auscultation for TMJ sounds, TMJ palpation for tenderness or tissue displacement, muscle tenderness palpation, and load testing of the patient's TMJs.

Testing of Tooth Mobility

• Manual evaluation involves using instruments to move teeth buccally and lingually.
• Fremitus assessment involves palpating buccal surfaces during patient up-and-down tapping to determine tooth movement from occlusal forces.
• Periodontometers are used to standardize minor tooth displacement measurements.

Study of Mounted Diagnostic Casts

• Mounted diagnostic casts can reveal discrepancies between initial contact in centric relation and maximal intercuspation, as well as occlusal discrepancies in excursions.

Techniques for Detecting Occlusal Disharmony

• Articulating paper foils/ribbons are used to mark premature tooth contacts and high force/premature contact areas.

Indicator Materials

• Silks strips: Relatively thin and flexible, adapting well to cusp and fossa structures, providing reliable contact markings.
• Foils are the thinnest indicator materials, providing more accurate readings compared to paper and silk strips.
• Occlusal wax indicators are similar to impression materials, placed on the maxillary arch to assess contact during maximum intercuspation.

T-Scan System

• A computerized device comprising a hand-held unit with a U-shaped pressure sensor and computer software.

Photo-occlusion System

• Thin photoplastic film is positioned on the occlusal surface for brief patient biting.
• Relative tooth contact intensity is measured using a polariscope.

Requirements for Occlusal Stability

• Maximum intercuspation, light or absent anterior contacts, well-distributed posterior contacts, cross-tooth stabilization, forces directed along the long axis of each tooth, smooth excursive movement without interference, no trauma from occlusion, favorable subjective response to occlusal form and function.

Occlusal Therapy

• The aim of occlusal therapy is to establish stable functional relationships to support optimal oral health, including the periodontium.
• Effective nonsurgical therapy reduces periodontal inflammation and promotes attachment healing, which stabilizes mobile teeth.
• Occlusal appliances are often needed to control excessive occlusal force and masticatory disharmony, thus securing a more stable occlusion.

Indications for Occlusal Therapy

• Occlusal trauma (e.g., bruxism, muscular dysfunction, certain TMJ conditions, food impaction).
• Increased tooth mobility
• Dental pain associated with occlusion or occlusal soft-tissue injury.
• Excessive occlusal contacts causing trauma to periodontium, joints, muscles or soft tissues.
• Occlusal interferences that worsen parafunctional habits.

Treatment Options

• Occlusal appliance therapy, occlusal adjustment, occlusal stability for restorative dentistry, orthodontic tooth movement, and orthognathic therapy are common treatment options .

Occlusal Adjustment

• Selective reshaping of occluding tooth surfaces to reduce occlusal interference and direct forces along the tooth's long axis.

Coronoplasty

• Retrusive prematurities are eliminated, ICP is adjusted for stable simultaneous contacts, excessive posterior-protrusive contacts are addressed, mediotrusive prematurities and laterotrusive prematurities and gross occlusal disharmonies are corrected, and contact relationships are rechecked.
• The correction of occlusal supracontacts includes techniques like grooving, spheroiding, and pointing.

Additional Notes

• No specific questions provided