TY - JOUR AU - Sorrentino, R. AU - Nagasawa, Y. AU - Infelise, M. AU - Bonadeo, G. AU - Ferrari, M. PY - 2018/05/29 Y2 - 2024/03/29 TI - In vitro analysis of the fracture resistance of CAD-CAM monolithic lithium disilicate molar crowns with different occlusal thickness JF - Journal of Osseointegration JA - J Osseointegr VL - 10 IS - 2 SE - Articles DO - 10.23805/jo.2018.10.02.04 UR - https://journalofosseointegration.eu/jo/article/view/205 SP - 50-56 AB - <p><strong>Aim: </strong>To compare the fracture resistance and mode of failure of CAD-CAM monolithic lithium disilicate crowns with different occlusal thickness.&nbsp;</p><p><strong>Materials and methods: </strong>Thirty CAD-CAM monolithic lithium disilicate crowns with different occlusal thickness were randomly distributed into 3 experimental groups: 0.5 mm (group 1), 1.0 mm (group 2) and 1.5 mm (group 3). The restorations were cemented onto human molars with a self-adhesive resin cement. The specimens were loaded until fracture; the fracture resistance and mode of failure were recorded. The data were statistically analyzed with the one-way ANOVA followed by the Fisher€™s Exact test with Bonferroni€™s correction (p=0.05).</p><p><strong>Results: </strong>The fracture resistance values of all the specimens exceeded the maximum physiological occlusal loads in molar regions. The highest fracture resistance was noticed in 1.0 mm-thick crowns. Ultrathin restorations (group 1) proved to be statistically less resistant to fracture than those of the other experimental groups (p&lt;0.05). The crowns were mainly interested by unrestorable fractures.</p><p><strong>Conclusions: </strong>The occlusal thickness of CAD-CAM monolithic lithium disilicate crowns influences either the fracture resistance and the mode of failure of the restorations; the occlusal thickness of such restorations can be reduced up to a lower bound of 1.0 mm in order to keep sufficient strength to withstand occlusal loads; CAD-CAM monolithic lithium disilicate crowns showed sufficient fracture resistance to be used in molar regions but not in an ultrathin configuration (0.5 mm).</p> ER -