Tooth Supported Overdenture

Introduction to Overdenture

• A removable partial or complete denture
• Covers and rests on one or more remaining natural teeth, roots, and/or dental implants

Tooth Supported Overdenture

• Supported by mucosa and a few remaining natural teeth or retained roots
• Altered to permit the denture to fit over them

Advantages of Tooth Supported Overdenture

1. Effects on Edentulous Ridge:
   • Maintains alveolar bone integrity
   • Decreases rate of bone resorption
2. Improved Stability:
   • Enhanced retention of the denture
3. Tactile Discrimination:
   • Preservation of periodontal membrane
   • Maintains proprioceptive impulses
4. Psychological Benefits:
   • Comfort and satisfaction for the patient
5. Economical:
   • Fast and inexpensive treatment
6. Convertibility:
   • Can convert to a conventional complete denture if necessary

Disadvantages of Overdenture

1. Plaque Retention:
   • Increases caries susceptibility
   • Risk of periodontal disease
2. Aesthetic Problems:
   • Over contouring issues, especially in canine region
3. Space Requirements:
   • Needs more inter-ridge space
4. Complexity:
   • Clinically more complex
5. Maintenance:
   • Requires more upkeep
6. Cost:
   • Higher initial costs (periodontal, endodontic treatments)

Indications for Overdentures

1. Patients with few natural remaining teeth and good prognosis
2. Congenitally defective teeth
3. Highly worn teeth (attrition, bruxism)
4. Xerostomic patients for increased retention

Contraindications for Overdentures

1. High caries index
2. Poor oral hygiene
3. Reduced inter-ridge space
4. Bone undercuts
5. Inability to perform endo and periodontal treatment
6. Mentally & physically handicapped patients

Selection of Abutments

1. Periodontal and Mobility Status:
   • Teeth with significant bone loss and mobility are unsuitable
2. Abutment Location:
   • Anterior ridge susceptible to stress
   • Cupids/bicuspids are preferred
3. Coronal Substance:
   • Sufficient to maintain abutment integrity

Techniques in Overdenture Construction

1. Simple Tooth Modification & Reduction:
   • Contour teeth to dome shape for space
2. Tooth Reduction with Cast Coping:
   • Preparation increases sensitivity
3. Endodontic Therapy with Amalgam/Composite Plug:
   • For insufficient inter-occlusal space
4. Endodontic Therapy with Cast Coping:
   • Requires endodontic therapy due to pulp exposure
5. Endodontic Therapy with Cast Coping & Attachments:
   • For additional retention

Types of Overdenture Attachments

• Zest anchor system
• Dalbo attachment
• Bar attachment

Single Complete Denture

• Occludes against natural teeth, fixed restoration, or previously constructed denture
• More complex than upper/lower complete dentures

Problems of Single Denture

• Heavy Occlusal Forces: From opposing natural teeth
• Single Denture Syndrome: Displacement due to unfavorable occlusal relations
• Complications: Combination syndrome, wear of natural teeth, denture fracture

Combination Syndrome and Associated Changes

• Destructive issues from long-term mandibular distal extension use
• Includes loss of bone, tuberosities down growth, hyperplasia, extrusion, etc.

Immediate Denture

• Definition: Placed immediately post-extraction
• Indications & Contraindications: For patients with social activity, hopeless teeth, stable health vs. poor health, uncooperative, bacteremia risk
• Advantages: Maintains appearance, support, less pain, adaptable
• Disadvantages: Undercut issues, try-in inability, cost, impaired function