Case 14: Altered cast technique for Cast Partial Denture

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Case 14: Altered cast technique for Cast Partial Denture

 Cast partial dentures(CPD) are superior to any other forms of partial acrylic dentures. However, they are technique sensitive and are considered the best when done precisely. There are so many factors which play a role in obtaining the best fit and longevity of any cast partial denture. One major consideration is the type of support on which the CPD rests.

In situations where the support is mainly from the edentulous ridges, the possibility for frequent relining is going to be a consideration on a long term. Likewise, special impression techniques are also a major consideration in Kennedy's class 1 situations with long span edentulousness.

Altered cast technique is a method where a functional impression is made to record the edentulous site in such a way that the load transferred on to the residual ridge is kept to a minimum and the frequency of relining and the rate of resorption is controlled.



 Here is a situation where there is Kennedy's class 1 edentulous site in the mandibular arch. The design considerations involved a an interrupted lingual plate as its major connector, RPI system on tooth 4.5 and a circumferential on 3.3. Mesh type of minor connector for the edentulous site.

Firstly, the frame is checked for a passive and an ideal fit. Once the frame is assessed, the same can be used for the special impression technique to fabricate an altered cast. Impression compound was used as the base material which was then scrapped and a tissue conditioner was used to record the functional impression.


 Once recorded, the mastercast which was initially used for the fabrication of the framework is marked for sectioning the edentulous site. It is then sectioned and the framework with the functional impression is seated and secured. Finally, beading and boxing is carried out to complete the fabrication of the altered cast.







This case was done by me during my Post graduation at V.S.Dental College & Hospital.


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