different designs of dental bridges

my seminar

1. Different designs of bridges By Yasmin M ohammed Group e2 University of Baghdad/college of dentistry

2. Fixed partial denture It is a fixed dental prosthesis which replace and restore the function and esthetic of one or more missing natural teeth ,it can not be removed from the mouth by the patient. It is primarily supported by natural teeth or root .

3. The bridge consists of : 1. Retainer : it is the part of the bridge which is cemented to the abutment teeth .it could be full metal ,full veneer with facing , partial veneer , post crown or inlay … etc .

4. 2. Pontic Is the part of the bridge which represent the missing tooth and it connected to the retainer by a connector

5. 3. Connector is the part of the bridge which connect the pontic and the retainer , it maybe rigid (solid joint ) or movable joint (precision attachment , key and key way )

6. Types of connectors 1. rigid 2. non rigid _ tenon mortise conectors _loop connectors _split pontic connectors _cross pin and wing connectors

7. Tenon mortise

8. Loop connectors split pontic

9. Cross pin and wing connectors

10. 4. Abutment Is the natural tooth which support the bridge and on which the retainer is cemented (tooth or root )

11. Crown_ root ratio Is the measurement of the length of tooth occlusal to the alveolar crest of the bone compare with the length of root embedded in the bone . The ideal crown root ratio for a tooth to be used as a bridge abutment is 1:2 , and the minimum ratio acceptable for prospective abutment under normal circumstances is 1:1 .

12. Antews low The root surface area ( pericemental area )of the abutment teeth should be more or at least equal to the root suface area ( pericemental area )of the missing teeth being replace .

13. Types of bridges There are 4 main type of bridges 1. fixed _ fixed bridge 2. fixed movable bridge 3.cantilever bridge 4.resin bonded bridge (conservative bridge )

14. Fixed _fixed bridge In this type the pontic is attached to the retainers (mesial and distal)by rigid connector(solid joint) so they should have one path of insertion . This is the most commonly used FPD .

15. Advantages : 1. maximum retention and support . 2. abutment teeth are splinted together . 3. the design is most practical for larger bridges . disadvantages 1.require preparation to be parallel 2. All the retainers are major retainers and require extensive ,destructive preparation of the abutment teeth . 3.Has to be cemented in one piece .

16. Fixed movable bridge In this type the pontic is attached to one distal major retainer (distal end of the pontic )by fixed connector while the other end is attached to the minor retainer (in front of pontic )by movable joint .it s indicated in case of drifted abutment teeth and difficulty to obtaining parallel abutments.

17. Advantages: 1. preparations do not need to be parallel to each other . 2. more conservative of tooth tissue because preparations for minor retainers are less destructive . 3. parts can be cemented separately . Disadvantages 1.more complicated to construct in laboratory than fixed fixed bridge . 2.difficult to make temporary bridge .

18. Preoperative picture

19. Tooth preparation for porcelain fused to metal restorations

20. Case Prefabricated castable bar attached between waxed up copings

21. Metal try-in

22. Bar attached parallel to the ridge on palatal aspect

23. Waxed up trial denture for removable partial denture

24. Wax added on labial flange of removable partial denture for lip support

25. Final cementation of porcelain fused to metal fixed partial denture and fixed component of Andrew's Bridge

26. Andrews bridge placement