AN IN VITRO STUDY OF THE CYTOTOXICITY OF GRADE IV COMERCIALLY PURE TITANIUM AND GRADE V (TI-6Al-4V) TITANIUM ALLOY USED IN DENTAL IMPLANTS

Date

2024-8

Type

PhD Thesis

Thesis title

yeditepe university

Author(s)

Adil Mokhtar Abdalla Essllami

Abstract

This study set out to employ the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to investigate the cytotoxic effects of commercially pure titanium (Grade IV) and its alloyTi-6Al-4V (Grade V) on the function of mice gingival fibroblasts (L 929 fibroblast) in cell culture. A total of thirty-two (n= 32) commercially pure titanium grade IV (ASTM F67) (No₌16) and titanium grade V (Ti6Al4V) (no₌16) were submitted to laboratory examination using a test setup like that recommended by International standard ISO 7405 guidelines. The grade IV specimen disks had a diameter of 6 mm and a thickness of 2 mm, but the grade V disks had a diameter of 8 mm and a thickness of 2 mm. The samples were placed in an incubator for 24, 48, and 72 hours, using a mixture of Roswell Park Memorial Institute (RPMI) medium, 10% fetal bovine serum (FBS), and 1% antibiotic. After each incubation period, the toxicity of the extracts on cultured mouse fibroblasts (L929) was assessed using the MTT test. The photometric experiments were performed using a high-quality UV/VIS spectrophotometer (Multiskan GO.USA) To evaluate cell viability, we desire to investigate the optimal circumstances for cell viability among these metals. The data were subjected to statistical analysis using a one-way repeated measures ANOVA test. Post-hoc tests were conducted at a significance threshold of p < 0.05 to examine the impact of time on cell viability percentage in each titanium grade type. The results show that after 24 hours, grade Ⅳ titanium had a 10% higher cell viability (80.3 ± 5.1%) than grade Ⅴ titanium (70.3 ± 4.1) (p < 0.001). After 48 hours, it rose by 9.9% and 5.4% (p < 0.001). Additionally, grade Ⅳ titanium boosted cell viability by 5.4% after 72 hours, compared to grade Ⅴ titanium (p < 0.001). As a conclusion, grade Ⅳ commercially pure titanium had superior cell viability than grade Ⅴ titanium alloy throughout incubation. Both grade IV titanium and grade V titanium alloy are suitable for dental usage.