J Adv Prosthodont.  2012 May;4(2):89-92.

Prosthetic misfit of implant-supported prosthesis obtained by an alternative section method

• Tiossi R
• Falcao-Filho HBL
• de Aguiar
• Rodrigues
• de Mattos
• Ribeiro RF

Abstract

PURPOSE
Adequate passive-fitting of one-piece cast 3-element implant-supported frameworks is hard to achieve. This short communication aims to present an alternative method for section of one-piece cast frameworks and for casting implant-supported frameworks.
MATERIALS AND METHODS
Three-unit implant-supported nickel-chromium (Ni-Cr) frameworks were tested for vertical misfit (n = 6). The frameworks were cast as one-piece (Group A) and later transversally sectioned through a diagonal axis (Group B) and compared to frameworks that were cast diagonally separated (Group C). All separated frameworks were laser welded. Only one side of the frameworks was screwed.
RESULTS
The results on the tightened side were significantly lower in Group C (6.43 +/- 3.24 microm) when compared to Groups A (16.50 +/- 7.55 microm) and B (16.27 +/- 1.71 microm) (P<.05). On the opposite side, the diagonal section of the one-piece castings for laser welding showed significant improvement in the levels of misfit of the frameworks (Group A, 58.66+/-14.30 microm; Group B, 39.48+/-12.03 microm; Group C, 23.13+/-8.24 microm) (P<.05).
CONCLUSION
Casting diagonally sectioned frameworks lowers the misfit levels. Lower misfit levels for the frameworks can be achieved by diagonally sectioning one-piece frameworks.

Keyword

Dental implants; Implant-supported dental prosthesis; Prosthesis fitting; Prosthodontics; Fixed partial denture; Dental soldering

MeSH Terms

Axis, Cervical Vertebra
Dental Implants
Dental Prosthesis, Implant-Supported
Dental Soldering
Denture, Partial, Fixed
Prostheses and Implants
Prosthesis Fitting
Prosthodontics
Welding
Dental Implants

Figure

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  Fig. 1 Framework transversely sectioned with a diagonal direction in the pontic area.

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  Fig. 2 Vestibular view of a laser-welded framework.

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  Fig. 3 Means and standard deviations for all groups and under all reading conditions.

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  Fig. 4 SEM image of the coronal section of the diagonally welded framework.

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