1. RETAINERS DEFINITION:
Any type of device used for stabilization or retention of prosthesis -- GPT
dr shabeel pn

2. Retainer for an FPD…
That component of an FPD which takes support from the abutment tooth and provides retention to the prosthesis

4. SELECTION OF RETAINERS
Retainer selection for abutment is critical and is dictated by the followings:
Age
DMF rate
Edentulous space-Partial veneer crown contraindicated in long span FPD
Periodontal support
Arch position of the tooth
Skeletal relationship

5. Inter occlusal & intraocclusal condition such as crown length
Oral hygiene of the patient
Vitality of the abutment teeth---endodontically treated teeth may have to be restored with core & post before designing the retainer

6. Condition of the abutment teeth
11) Cost
12) Preservation of the tooth structure----Buccal surface should be conserved. Partial veneer crown is more conservative than full crown . All ceramic crowns are least conservative

7. Types of retainers Classified as: Based on tooth coverage
Full veneer crown
Partial veneer crown
Conservative (minimal prep.) retainers

8. Based on material used All metal retainers Metal ceramic retainers
All ceramic retainers
All acrylic retainers

9. Full veneer crowns Covers all 5 surfaces of abutment
Most retentive of the veneer preparations
Compared to partial veneer designs,full veneer crown exhibits superior resistance nd retention
Used on those teeth whose restoration demands max. retention.

10. Variations—Metal ceramic crowns and all ceramic crowns used in situations that requires a good cosmetic results
The full veneer crown should be used when less extensive and less destructive design have been considered and found lacking in retention ,resistance ,coverage or esthetics to properly restore the tooth

11. Partial veneer crown
Preferred than full veneer crown because they requires less tooth reduction
Crown does not cover the entire abutment
Facial surface is left intact for superior esthetics
Used when minimal retention is sufficient and when abutment tooth is healthy

12. Contra indications
In long span FPDs
Endodontically treated tooth
Dentition with active caries or periodontal disease
Poorly aligned abutment tooth

13. Advantages Conservation of tooth structure
Reduced pulpal and periodontal insult during tooth prep
Improved access for finishing by dentist & oral hygiene by patient

14. Less of margin approximate soft tissues subgingivally and hence less gingival involvement than complete coverage
Remaining intact facial or buccal tooth surface permits electric vitality test

15. Disadvantages Less retention & resistance than complete crowns
Some metal displayed in completed restoration—unaesthetic
Tooth prep is difficult because only limited
adjustments can be made in the path of placement

16. Resin bonded retainers (Maryland bridges)
Require minimal tooth preparation
Acid etched
Esthetically appealing
Economical , conservative , functional & do not irritate soft or hard tissues

17. Indication
As retainers of FPD for abutment with sufficient enamel to etch
Splinting of periodontally compromised teeth
Stabilizing dentition after orthodontic treatment

18. Contraindication In patients with sensitivity to base metal alloys
When facial esthetic of abutment require improvement
Inadequate enamel surface to bond eg;caries,existing restoration
Incisor with extremely thin facio-lingual dimension

19. Advantages
Non invasive to dentin with lingual and proximal tooth preparation including occlusal rest
Conservative with undeniable patient appearance
Tissue tolerant because of Supragingival margin,without pulpal irritation
Reduced cost and less chair side time

20. Disadvantage Demanding technique and tooth prep. Plaque accumulation
Bulky contour
Restricted to single pontic placement
Graying out of teeth that are thin labiolingually

21. Based on material used All metal retainers Metal ceramic retainers
All ceramic retainers

22. All metal retainers
Partial or full veneer crown
Require minimal tooth reduction
Strong even in thin sections

23. Metal ceramic retainers
Indicated on teeth that require complete coverage & esthetic demand
Can accommodate cast or soldered connectors
Can afford high force—metal
Require more teeth reduction

24. Indication Extensive tooth destruction as a result of caries or trauma
Existing previous restoration that precludes the use of a more conservative restoration
Need for superior retention and strength
Endodontically treated tooth

25. Contraindication
Whenever a more conservative retainer is feasible

26. All ceramic
Primary purpose ---to achieve best possible esthetic results
Risk of reduced restoration longevity—potential for fracture ,inferior marginal adaptation than PFM retainer

27. Telescopic retainers
Used when path of insertion of FPD does not coincide with long axis of abutment
Design involves fabricatin of two copings one over the other
Internal or primary coping function to modify the morphology of tooth –path pf insrtn changed
Secondary coping designed to fit over primary

28. REFERENCES Fundamentals of Fixed Prosthodontics Herber T.Shillingburg
Contemporary Fixed Prosthodontics
Rosenstiel,Land,Fujimoto
Tylmans Theory and Practice of Fixed Prosthodontics
Textbook of Prosthodontics-Deepak Nallaswamy

29. Thanking you…..
dr shabeel pn