Conectors in fpd

Conectors in fpd

1. CONNECTORS IN FPD

2. CONTENTS INTRODUCTION DEFINITION REQUIREMENTS OF CONNECTORS DESIGNING OF CONNECTORS RIGID CONNECTORS Casted connectors Soldered connectors Welded connectors Loop connectors NON-RIGID CONNECTORS Dovetail connectors Split pontic connectors Cross pin & wing connectors CONCLUSION REFERENCES

3. INTRODUCTION

4. DEFINITIONS “The Connector is that part of a fixed partial denture or splint that joins the individual components (retainers and pontics) together” -RESENSTEIL “That part of fixed partial denture which connects pontic and retainer and can be rigid or non-rigid” -SHILLINGBURG “The portion of a fixed partial denture that unites the retainer(s) and pontic(s)” -GPT 9

5. REQUIREMENTS OF CONNECTORS Sufficiently strong to resist all the forces of mastication N o likelihood of it wearing and fracturing during a life time. Placed as lingually and incisally as possible for self cleansing. Depth of connector should always be sufficient to provide adequate strength . It should occupy a gap width of about 0.25mm Should preserve the interproximal embrasure and occupy normal anatomic interproximal areas. Large to withstand distortion .

6. DESIGNING OF CONNECTORS HYGIENE CONSIDERATIONS BIOLOGIC CONSIDERATIONS MECHANICAL CONSIDERATIONS AESTHETIC CONSIDERATIONS

7. A.HYGIENE CONSIDERATIONS Mesio-distally smooth transition Highly polished tissue surface Curved facio-linguallyfacilitate cleansing & prevent plaque accumulation Inciso-cervicallyshould not be bulky Occupy with in the normal anatomic inter-proximal contact areas

8. B.BIOLOGIC CONSIDERATIONS pulp size and crown height can be limiting factors for placement of box in retainers of nonrigid connectors Connectors in anterior region are placed slightly lingual

9. C.MECHANICAL CONSIDERATIONS Buccolingual cross section elliptical shape Major axis of ellipse is parallel to the applied force But in most cases greater dimension is perpendicular to the applied forceresulting in week connection

10. D.AESTHETIC CONSIDERATIONS Large and inappropriately placed metal exposure and compromised esthetics To improve estheticsslight lingual placement Should occupy normal anatomic inter-proximal area

11. RIGID CONNECTORS Most commonly used Ideal for short span Can be made by: Casting Soldering Welding Indications When entire load can be directly transferred to abutments Contraindications Existing diestima is to be preserved Tilted abutment Long span bridges

12. 1.CAST CONNECTORS

13. ADVANTAGES: Convenient method Minimizes the steps in laboratory fabrication DISADVANTAGES: Difficulty in reflowing proximal margins Pattern removal from die is difficult Fit of the individual retainer may be affected No opportunity to verify fit of individual retainers in mouth CONTRAINDICATIONS: - 1 . F.P.D’s more than 3 units 2. Partial veneer F.P.D’s

14. 2.SOLDERED CONNECTORS

15. COMMONLY USED DENTAL SOLDERS: Gold solders Silver solders INDICATIONS: FPD’s more than 3 units When FPD fabricated by cast connectors exhibit high marginal discrepancy When cast FPD do not have proper fit Repair of fractured connectors DISADVANTAGES: Dirt or surface oxides on the connector surface can reduce wetting & impede successful soldering

16. 3.WELDERED CONNECTORS Connector is formed by melting adjacent surface with heat or pressure Filler metal with same melting temperature of parent metal is used Laser welding is commonly used

17. 4.LOOP CONNECTORS

18. ADVANTAGES: Enhance natural appearance of restoration Maintains diastema Proper emergence profile DISADVANTAGES: Requires additional laboratory procedure Difficulty in maintenance and oral hygiene May effect phonetics, especially linguopalatal sounds

19. NON-RIGID CONNECTORS TYPES: Dove tail connectors (key and ways) or (tenon – Mortise) Split pontic Cross pin and wing connectors. INDICATIONS OF NON-RIGID CONNECTORS The existence of P ier abutment T he existence of malaligned abutment Presence of mobile teeth Long span FPD Presence of questionable distal abutment When connecting to osseointegrated implants

20. 1.DOVETAIL CONNECTORS

21. 1.DOVETAIL CONNECTORS ADVANTAGES: Relieve stress on abutments. Acts as a splint of periodontically weakened teeth. Allows for easy repair. In case of fracture, not the whole assembly has to be repaired only the defective segment has to be removed and repaired. DISADVANTAGES: Time consuming. Cost factor. Require extensive tooth preparation. INDICATIONS: In periodontally weak abutments For relieving stress on midspan on long pontics In cases of long fixed partial dentures In cases of heavy occlusal forces CONTRAINDICATIONS: Cannot be used in short abutments. Medically compromised patients. Patients not willing for extensive tooth preparations.

22. 2.SPLIT PONTIC CONNECTORS

23. ADVANTAGES: When problem occurs only the affected segment can be removed and repaired or remade. No need to remove the whole assembly. Stresses that are to be applied are evenly distributed. Allows some degree of movement in function and hence protects the abutment overloading. Also act as a splint. DISADVANTAGES: More time consuming. Cost factor. INDICATIONS: This is an attachment that is placed within the pontic. It is particularly useful in tilted abutment cases, where the conventional dovetail would necessitate the drastic preparation in the distal aspect of the pier abutment. Used in pier abutments.

24. 3.CROSS PIN AND WING CONNECTORS :

25. ADVANTAGES: No need to remove the whole assembly if required. Even stress distribution. Reduces the amount of force on abutments. DISADVANTAGES : Time factor. Additional laboratory steps required for pin fabrication. Technique sensitive. INDICATIONS: The design will be primarily used to accommodate the abutment teeth with disparate long axis. Used in case of tilted molars.

26. CONCLUSION

27. REFERENCES Fundamental of Fixed Prosthodontics IIIrd Edition by Herbert T.Shillingburg. Contemporary Fixed Prosthodontics IIIrd Edition by Rosenthal, Land & Fujimoto. Yaqoob A, Rasheed N, Ashraf J, Yaqub G. Nonrigid semi-precision connectors for FPD. Dent Med Res 2014;2:17-21. Karla A, Gowda ME,Verma K. Aesthetic rehabilotation with multiple loop connectors. Contemp Clin Dent.2013;4:112-5

28. Thank you