Jemds.com Original Research Article J. Evolution Med. Dent. Sci./eISSN- 2278-4802, pISSN- 2278-4748/ Vol. 9/ Issue 10/ Mar. 09, 2020 Page 705 Influence of Shear Bonding Strength of Lithium Disilicate to Enamel under Different Surface Treatments Hisham Abdullah Mously 1 , Sohil Ahmed Kazim 2 , Rashad Nabeel Nageeb 3 , Ghada Hussein Naguib 4 , Mohamed Tharwat Hamed 5 1 Department of Oral & Maxillofacial Prosthodontics, King Abdulaziz University, Jeddah, Saudi Arabia. 2 King Abdulaziz University, Jeddah, Saudi Arabia. 3 King Abdulaziz University, Jeddah, Saudi Arabia. 4 Department of Restorative Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia, and the Department of Oral Biology, Cairo University, Cairo, Egypt. 5 Department of Oral & Maxillofacial Prosthodontics, King Abdulaziz University, Jeddah, Saudi Arabia and the Department of Fixed Prosthodontics, Cairo University Faculty of Dentistry, Cairo, Egypt. ABSTRACT BACKGROUND Accurate diagnosis and proper treatment planning should be established before making any prosthetic rehabilitation to restore the good appearance of the tooth, a better smile, phonetics, and to achieve perfect occlusion/mastication. We wanted to evaluate the changes of surface treatment protocols on the tensile bonding strength between enamel and ceramic restorations (lithium disilicate). METHODS A total of 20 freshly extracted, non-carious teeth were stored in normal saline solution at 25°C until used. Clean enamel surfaces 2 mm X 2 mm were obtained from the extracted teeth by using wheel diamond bur. Each enamel side received one E- max sprue, so four sprues of different surface treatment protocols per tooth (G1 TS: Etching, bonding, and curing. CS: Etching, monobond, curing, overall light cure) (G2 TS: Bonding, curing, self-etch / self-adhesive resin cement, overall light cure. CS: Monobond etch and prime) (G3 TS: Etching, bonding without curing. CS: Etching, monobond, curing, overall light cure) (G4 TS: Etching, bonding, curing. CS: Etching, monobond, bonding, curing, light-cure resin cement, overall light cure). Tensile bonding strength was measured using the Instron testing machine. One-way ANOVA test was used to analyse the data. RESULTS The highest mean was observed in Group 3 (124.34±43.47) followed by Group 1 (104.29±50.09), which is control group. In contrast, the lowest mean was observed in Group 2 (83.64 ± 53.56) and Group 4 (94.14±57.91). The results of ANOVA test have shown a significant difference between the surface treatment groups at 5% significance level. CONCLUSIONS Hydrofluoric acid and primer/silane coupling agent create a porous surface on the ceramic that allow a good interaction with silane coupling agent. KEY WORDS Enamel, Hydrofluoric Acid, Lithium Disilicate, Primer, Silane, Tensile Bonding Strength Corresponding Author: Mohamed Tharwat Hamed, BDS, MSD, CAGS, MPH, MPHE, DMSc. Department of Fixed Prosthodontics, Cairo University School of Dentistry, Alkasr Aleiny, Almanyal, Cairo, Egypt. E-mail: mohsarwat62@gmail.com DOI: 10.14260/jemds/2020/154 Financial or Other Competing Interests: None. How to Cite This Article: Mously HA, Kazim SA, Nageeb RN, et al. Influence of shear bonding strength of lithium disilicate to enamel under different surface treatments. J. Evolution Med. Dent. Sci.2020;9(10):705-710, DOI: 10.14260/jemds/2020/154 Submission 04-10-2019, Peer Review 07-02-2020, Acceptance 14-02-2020, Published 09-02-2020.