OVERDENTURES - Part 1 скачать в хорошем качестве

OVERDENTURES - Part 1

Overdentures is defined as any removable dental prosthesis that covers and resta on one or more remaining natural teeth, the roots of natural teeth and/ or dental implants. Also called as biologic denture, telescopic denture, onlay denture, hybrid denture, root supported denture and superimposed denture. Rationale - preserves bone, preserves periodontium and establishes favorable crown root ratio. Preventive Prosthodontics - emphasizes the importance of any procedure that can delay or eliminate future Prosthodontic problems. This concept is highlighted in treatment of overdentures. Requirements of overdentures -reduction of crown root ratio reduces mobility of tooth, basal seat tissues should be well healed, simple to fabricate, teeth or root should have sound periodontal health, easy manipulation of dentures Classification of overdentures 1. On the basis of method of abutment preparation - non copings, copings and attachments 2. On the basis of method of retention - copings, attachments, sleeve coping prosthesis, submucosal vital root retention, implant supported 3. On the basis of time of fabrication - immediate overdentures, transitional overdentures and training overdentures 4. On the basis of type of tooth supported overdentures - conventional complete overdentures, immediate complete overdentures 5. On basis of type of design - bare root, telescopic and attachment fixation overdentures Advantages - preserves bone preserves proprioceptive response provides static stable base enhances retention inexpensive approach to restore function in congenital defects such cleft lip, partial anodontia excellent patient acceptance easy maintenance easy conversion to complete denture reasonable cost reduces horizontal or torquing forces roofless denture or open palate is possible Disadvantages- susceptible to caries bony undercuts limits path of insertion overcontouring or undercontouring retained teeth susceptible to periodontal breakdown Indications - presence of few teeth younger patients with less teeth congenital defect patient with high vault palate and sloping ridges patient with poorly defined sublingual fold coperative and motivated patient Contraindications - physically and mentally challenged patients uncooperative and unmotivated patient teeth with class III mobility soft tissue and bony defects which cannot be corrected vertical fracture of tooth mechanical perforation of tooth or root horizontal fracture of root below bony crest broken instrument in root canal Link for surveying -    • Cast Tilting during Surveying Procedure