Intaglio Surface Adaptation of Removable Partial Denture Framework Fabricated by Various Data Acquisition Techniques and Fabrication Approaches.

OBJECTIVES

The aim of this study was to compare intaglio surface adaptation of the removable partial denture framework among various data acquisition techniques and fabrication approaches using three-dimensional comparison by metrology software.

MATERIALS AND METHODS

The partial edentulous typodont model with five digital superimposition landmarks was duplicated and scanned for the digital reference model. Three approaches were the conventional lost-wax (group I; LWT,  = 5), intraoral digital impressions combined with PolyJet printing and lost-wax (group II; IP-LWT,  = 5), and extraoral digital impressions combined with PolyJet printing and lost-wax (group III; EP-LWT,  = 5). Each framework was scanned and superimposed with the reference model. The misfits at 53 locations were measured.

STATISTICAL ANALYSIS

Data were statistically analyzed by one-way analysis of variance, followed by Tukey's honestly significant difference for pairwise comparisons ( < 0.05).

RESULTS

Significant differences were found between three approaches at the reciprocal arm, terminal part of the retentive arm, rest, and major connector ( < 0.05). In the LWT group, the reciprocal arm and palatal vault region of major connector had the lowest misfits, but the highest misfit was found in the midline region ( < 0.001). In the IP-LWT group revealed the most excessive contact at the terminal part of the retentive arm (-0.111 ± 0.038 mm,  = 0.031), with the highest misfit at the rest area ( < 0.001).

CONCLUSION

A difference in adaptation was found in several removable partial denture framework components among three approaches. The LWT group had a better adaptation than other groups. Nevertheless, a clinically acceptable adaptation was seen in all three approaches.