Implant-supported restorations have been accepted as an alternative treatment for the rehabilitation of edentulous spaces. Despite the high success rates, implant failures are inevitable and classified as early or late implant failures. Late implant failures are observed after prosthetic restoration which is primarily related to biomechanical complications. Since occlusal loads are transferred to the bone interface via prosthesis, many factors have a biomechanical effect on the stress distribution on the bone-implant-prosthesis complex. Among these factors, the effect of prosthetic restoration material was investigated in the present study by comparing the stress distribution and failure load of CAD/CAM-manufactured current glass ceramics.

Fracture of ceramic restorations is one of the most common problems observed in clinical use. Therefore, a ceramic crown should have sufficient fracture strength during oral function. To solve this problem, laboratory tests can be used as they facilitate the evaluation of the fracture strength of materials with crown-shaped specimens. Although laboratory tests should be comparable to intraoral conditions, there may be some limitations such as dynamic load and thermal effect as in our study. For this reason, these effects should be evaluated in further studies. In addition, they do not adequately simulate the clinical fractures of ceramic restorations. Cracks occur at the cervical margin for clinical crowns, but in laboratory tests, contact damage occurs with the loading device. This was confirmed by our study as all fractures started from the occlusal surface.

The LDS ceramic has been commonly used in wide range indications. Despite the low opacity of the ceramic, it can be veneered to improve esthetic and sufficient veneer support. A long-term clinical follow-up study indicated that the survival of veneered LDS restorations was 97.4% for 5 (five) years, and the anterior and posterior regions were 93.8% and 100%  (one hundred percent)for 8 (eight) years respectively.