IADR Abstract Archives
Marginal and Internal Fit of CEREC E.max and Celtra Duo Crowns
Objectives: is to compare marginal chipping and marginal fit of E-max (EM) and Celtra Duo (CD) all-ceramic crowns fabricated using CEREC Omnicam and chair-side milling chamber (CEREC MC XL)
Methods: Tooth # 15 prepared for all-ceramic crown on ivorine typodont. Maxillary typodont was then digitized, using CEREC Omnicam intraoral scanner. STL file was used to mill a replica of the maxillary arch out of epoxy resin to serve as master model and 30 duplicate dies of maxillary second bicuspid to enable marginal fit assessment. A total of 15 CD crowns and 15 EM crowns were designed chair-side and fabricated using CEREC MC XL milling chamber. Micro-computed tomography (micro-CT) was utilized to assess marginal and internal fit of crowns in both groups. Marginal gap (MG) measurements were done at 20 systematically selected points/crown. frequency and severity of marginal chipping. Internal fit was measured at 7 systematically selected points per crown. Crowns with vertical MG>120μm at more than five points were considered unacceptable and were rejected. Scanning electron microscope (SEM) was used to further evaluate marginal chipping. The results were analyzed by t-test and chi-square
Results: CD crowns showed significantly smaller MG (47.50 μm ± 16.17) as compared to EM (78μm ± 27.26). CD crowns had smaller internal space than lithium disilicate (41μm ± 11.92 and 56.8μm ± 12.49 respectively). Chipping was more frequent in EM than CD crowns (53% vs. 27%). Overall, two EM crowns were deemed unacceptable based on the MG measurements, while all crowns in CD group were deemed acceptable. SEM confirmed micro-CT findings regarding the extent of marginal chipping
Conclusions: CD crowns resulted in better marginal fit and less chipping compared to E.max crowns fabricated using CEREC technology.
Methods: Tooth # 15 prepared for all-ceramic crown on ivorine typodont. Maxillary typodont was then digitized, using CEREC Omnicam intraoral scanner. STL file was used to mill a replica of the maxillary arch out of epoxy resin to serve as master model and 30 duplicate dies of maxillary second bicuspid to enable marginal fit assessment. A total of 15 CD crowns and 15 EM crowns were designed chair-side and fabricated using CEREC MC XL milling chamber. Micro-computed tomography (micro-CT) was utilized to assess marginal and internal fit of crowns in both groups. Marginal gap (MG) measurements were done at 20 systematically selected points/crown. frequency and severity of marginal chipping. Internal fit was measured at 7 systematically selected points per crown. Crowns with vertical MG>120μm at more than five points were considered unacceptable and were rejected. Scanning electron microscope (SEM) was used to further evaluate marginal chipping. The results were analyzed by t-test and chi-square
Results: CD crowns showed significantly smaller MG (47.50 μm ± 16.17) as compared to EM (78μm ± 27.26). CD crowns had smaller internal space than lithium disilicate (41μm ± 11.92 and 56.8μm ± 12.49 respectively). Chipping was more frequent in EM than CD crowns (53% vs. 27%). Overall, two EM crowns were deemed unacceptable based on the MG measurements, while all crowns in CD group were deemed acceptable. SEM confirmed micro-CT findings regarding the extent of marginal chipping
Conclusions: CD crowns resulted in better marginal fit and less chipping compared to E.max crowns fabricated using CEREC technology.