305, respectively) (Pearson’s correlation coefficient). Conclusion: Although all four IRCs presented nonsignificant DC values, flexural strength Aurora Kinase inhibitor and microhardness values varied between materials with and without thermocycling. “
“Restorative material selection in complete mouth rehabilitation is an important factor in long-term management of potential technical complications. The aim of this study was to evaluate in vitro the reliability (fracture resistance) of lithium disilicate fatigued with different restorative materials. A step-stress
accelerated life-testing model was used. Seventy disc specimens were heat-pressed. Five groups of different indenter materials fatigued the lithium-disilicate specimens: group WC (tungsten carbide served as a control),
group PR (interpenetrating polymer network [IPN] resin-based denture tooth), group POM (heat-pressed leucite glass-ceramic), group LD (heat-pressed lithium disilicate), and group ZR (zirconium Y-27632 dioxide). Lithium-disilicate specimens were randomly divided into four groups (n = 14). Specimens were fatigued to failure according to three step-stress profiles: light, moderate, and aggressive. Use level probability Weibull plots were generated, and each group’s reliability, failure rate, and mean life to failure were calculated. The IPN resin-based denture tooth group had the highest reliability and mean life to failure, and lowest failure rate as compared to lithium disilicate and zirconium dioxide. No significant difference existed between the reliability of the tungsten carbide
Urease and leucite glass-ceramic groups and the IPN resin-based denture tooth group. Lithium-disilicate specimens fatigued with IPN resin-based denture teeth exhibited higher reliability than specimens fatigued with lithium disilicate and zirconium dioxide. There was a difference in fracture characteristics in lithium-disilicate specimens fatigued with tungsten carbide, lithium disilicate, and zirconium dioxide, versus those fatigued with IPN resin-based denture teeth and leucite glass-ceramic material. “
“In an abutment screw fracture, it is generally a challenge for the clinician to remove fractured fragments. In some cases, the screw cannot be removed, and alternative solutions should be considered. This clinical report describes the replacement of a ball attachment with a fractured screw, which was impossible to retrieve, with a cast dowel with ball attachment. The patient who presented to the Department of Prosthodontics, Yeditepe University, Faculty of Dentistry was a 65-year-old woman, wearing a mandibular complete denture supported by two implants for 4 years. She complained about the loss of retention of the denture because of the fractured abutment screw, and it was found that another dentist had previously tried to retrieve the fractured screw with no success. It was decided to construct a cast dowel with ball attachment to improve retention without sacrificing the implant.