AÇIKALIN, Ayça Çukurova Üniversitesi - Diş Hekimliği Fakültesi - Protetik Diş Tedavisi Anabilim Dalı, TURKEY , BUDAK, Ecmel Nadir Çukurova Üniversitesi - Diş Hekimliği Fakültesi - Protetik Diş Tedavisi Anabilim Dalı, Turkey , UÇAR, Yurdanur Çukurova Üniversitesi - Diş Hekimliği Fakültesi - Protetik Diş Tedavisi Anabilim Dalı, Turkey

COMPARING THE INTERNAL FIT OF CONVENTIONALLY CASTAND COPYMILLED METAL FRAMEWORKS

26195

Objective: The purposes of this study were to compare the internal fit of copy-milled and conventionally cast crowns and evaluate the effect of porcelain firing cycles on crown fit. Material andMethod: Gypsum duplicates were made from prepared tooth.Metal frameworks were established using conventional casting method and copy milling technique (N=15 per group). Metal frameworks were cemented on gypsum dies using light body additional silicone before and after porcelain application using finger pressure. Weight of silicone material was measured. The cement thickness of metal frameworks was compared 3 dimensionally. The crowns were later recemented on gypsum dies using polycarboxylate cement, embedded in resin and sectioned longitudinally in labio-lingual direction. The internal gap width was measured on sectioned specimens on five different points using stereomicroscope. T-test was used for statistical analysis (α=0.05). Results: The mean silicone weight of metal frameworks were 14.04 ± 1.21 mg and 11.45 ± 1.14 mg, respectively, for copy-milled and cast frameworks. An increase in silicone weight was observed after porcelain firing cycles for both copy-milled (15.56 ± 1.59 mg) and cast groups (13.16 ± 3.05 mg). The cement thickness of sectioned specimens were higher in copy milled group (232 ± 120 μm) compared to conventionally cast group (140 ± 48 μm). Significant differences were observed between two methods for all comparisons (p 0.05). Porcelain firing application caused an increase in cement thickness. Conclusion: Although statistically significant differences were observed between conventionally casting and copy milling techniques, whether the difference is significant for clinical applications should be further evaluated. Porcelain application increases the cement film thickness.

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Copy , milling , base metal , internal gap

Acta Odontologica Turcica

176