TY - JOUR
T1 - Failure load effect of molar axial wall height with CAD/CAM ceramic crowns with moderate occlusal convergence
AU - Hoopes, Wyeth
AU - Cushen, Sara
AU - DuVall, Nicholas
AU - Wajdowicz, Michael
AU - Brewster, John
AU - Roberts, Howard
N1 - Publisher Copyright:
© 2018 Wiley Periodicals, Inc.
PY - 2018/5/1
Y1 - 2018/5/1
N2 - Objectives: To evaluate the significance of axial wall height (AWH) in molar fracture resistance involving CAD/CAM adhesively bonded, all-ceramic full coverage restorations on preparations with moderate total occlusal convergence (TOC) (16°). Materials and Methods: 60 newly extracted maxillary third molars were divided into 5 groups (n = 12). Specimens were prepared for full-coverage, all ceramic restorations with occlusal cervical AWHs of 4, 3, 2, 1 as well as a flat preparation (0 mm AWH) with all preparations with AWH containing a moderate 16° TOC. Scanned preparations were fitted with a lithium disilicate restoration with a self-adhesive resin luting agent after intaglio surface preparation with hydrofluoric acid and silanation. Specimens were stored at 37°C/98% humidity for 24 hours and tested to failure at a 45° angle applied to the palatal cusp on a universal testing machine. Mean results were analyzed using ANOVA/Tukey's (P =.05). Results: Preparations containing 2, 3, and 4 millimeters of AWH demonstrated similar and higher resistance to fracture than the 1 and zero millimeter AWH groups. Conclusions: Under the conditions of this study, results suggest that adhesive CAD/CAM technology may compensate for reduced axial wall height. However, more definitive results depend on fatigue testing. Clinical Significance: These in vitro results suggest that adhesive CAD/CAM technology may compensate for less than optimal AWH.
AB - Objectives: To evaluate the significance of axial wall height (AWH) in molar fracture resistance involving CAD/CAM adhesively bonded, all-ceramic full coverage restorations on preparations with moderate total occlusal convergence (TOC) (16°). Materials and Methods: 60 newly extracted maxillary third molars were divided into 5 groups (n = 12). Specimens were prepared for full-coverage, all ceramic restorations with occlusal cervical AWHs of 4, 3, 2, 1 as well as a flat preparation (0 mm AWH) with all preparations with AWH containing a moderate 16° TOC. Scanned preparations were fitted with a lithium disilicate restoration with a self-adhesive resin luting agent after intaglio surface preparation with hydrofluoric acid and silanation. Specimens were stored at 37°C/98% humidity for 24 hours and tested to failure at a 45° angle applied to the palatal cusp on a universal testing machine. Mean results were analyzed using ANOVA/Tukey's (P =.05). Results: Preparations containing 2, 3, and 4 millimeters of AWH demonstrated similar and higher resistance to fracture than the 1 and zero millimeter AWH groups. Conclusions: Under the conditions of this study, results suggest that adhesive CAD/CAM technology may compensate for reduced axial wall height. However, more definitive results depend on fatigue testing. Clinical Significance: These in vitro results suggest that adhesive CAD/CAM technology may compensate for less than optimal AWH.
KW - CAD/CAM
KW - adhesion
KW - axial wall height
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U2 - 10.1111/jerd.12366
DO - 10.1111/jerd.12366
M3 - Article
C2 - 29383829
AN - SCOPUS:85041185674
SN - 1496-4155
VL - 30
SP - 249
EP - 253
JO - Journal of Esthetic and Restorative Dentistry
JF - Journal of Esthetic and Restorative Dentistry
IS - 3
ER -