Fracture Resistance of Different Lithium Disilicate Restorations After Endodontic Access Cavity Preparation: Effect of Repair Method

Hebah Agamal Abdulghafor, Graduate student, Department of Fixed Prosthodontics, Mansoura University, Mansoura, Dakahlia, EgyptFollow
Essam A. Khedr, Lecturer, Department of Fixed Prosthodontics, Mansoura University, Mansoura, Dakahlia, Egypt
Nesma M. Elgohary, Assistant professor, Department of Fixed Prosthodontics, Mansoura University, Mansoura, Dakahlia, Egypt
Walid A. Al-zordk, Professor, Department of Fixed Prosthodontics, Mansoura University, Mansoura, Dakahlia, Egypt

Article Type

Original Article

Section/Category

Restorative Dentistry

Abstract

Objective: To evaluate the effect of different repair methods on the fracture resistance of lithium disilicate restorations after endodontic access cavity preparation. Materials and Methods: One hundred sixty sound human mandibular first molars were prepared and restored with four types of lithium disilicate–based crowns: IPS e.max CAD, GC Initial LiSi Block, Straumann n!ce, and CEREC Tessera (n = 40 each). Standardized endodontic access cavities were prepared in all specimens, then repaired using one of four techniques: (1) inlay restoration with Monobond Etch&Prime, (2) inlay restoration with IPS Ceramic Etching Gel + Monobond Plus, (3) direct composite with IPS Ceramic Etching Gel + Monobond Plus, or (4) direct composite with Monobond Etch&Prime. All specimens were thermocycled and subjected to fracture resistance testing using a universal testing machine. Data were analyzed with one-way and two-way ANOVA. Results: Both ceramic material and repair method significantly affected fracture resistance (p < 0.001). IPS e.max CAD and Straumann n!ce crowns exhibited the highest fracture resistance, while GC Initial LiSi Block showed the lowest. Inlay restorations consistently demonstrated higher fracture resistance compared with direct composite repairs across all ceramic groups. Two-way ANOVA confirmed that both variables (material and repair technique) were significant predictors of fracture resistance. Conclusions: Repair method plays a decisive role in the fracture resistance of lithium disilicate restorations after endodontic access. Inlay restorations provided superior reinforcement compared with direct composite repairs. Selection of ceramic material also influenced outcomes, with IPS e.max CAD and Straumann n!ce showing the best performance.

Keywords

Lithium disilicate, fracture resistance, endodontic access, ceramic repair, inlay restoration, composite repair.

How to Cite This Article

Abdulghafor H , Khedr E , Elgohary N , Al-zordk W . Fracture Resistance of Different Lithium Disilicate Restorations After Endodontic Access Cavity Preparation: Effect of Repair Method. Mans J Dent. 2025; 12(4):
Available at: https://doi.org/10.61793/2812-5479.1172