1. Overdenture
a complete or partial removable denture supported by retained roots that is intended to provide improved support, stability, and tactile and proprioceptive sensation and to reduce ridge resorption. (Mosby. Mosby's Dental Dictionary. Elsevier, 2004.).

10. Advantages
Preserve alveolar ridge
Possibly -support -proprioreception -retention (eventually) -stress distribution

11. Disadvantages Poor oral hygiene -caries and periodontal disease
Soft tissue undercuts -esthetics -retention
Breakage of denture -thin -stress concentration over abutments

12. Selection of abutment teeth
One per quadrant
Not adjacent teeth
Usually mandibular cuspids and premolars
Maxillary cuspids frequently cause esthetic and retention problems due to soft tissue undercuts

13. Overdentures
Regard as transitional
- need perfect oral hygiene -daily non acidulated topical fluoride (sodium fluoride)
Probably better to place 2 implants