Authors : Punia K, Shetty D, Sharma P, Kumar P, Raza M
DOI : 10.18231/j.jds.2019.021
Volume : 7
Issue : 2
Year : 2019
Page No : 84-88
Objective: To evaluate and compare the shear bond strength (in vitro) and survival rate (in vivo) of molar tubes with conventional and modified mesh base designs.
Materials and Methods: Molar tubes of two different base design ie conventional (American Orthodontics) and modified base design (Ortho Organizers) were evaluated and compared for shear bond strength and survival. 20 molar tubes of each type were bonded on freshly extracted first permanent molars. Shear bond strength was tested using a Universal testing machine. 20 patients requiring fixed orthodontic treatment were selected. Molar tubes with two different base designs were placed on alternate sides in the four quadrants so that each arch had molar tubes of both types. Survival of the bonded tubes was evaluated monthly for a period of six months.
Results: Molar tubes having conventional mesh base design showed greater shear bond strength (10.49 Mpa) as compared to modified mesh base design (10.41 Mpa). The difference was found to be statistically significant (p=0.004). However, tubes with a modified mesh base (OO) showed a greater survival rate (95%) compared to those with conventional mesh base (85%).
Conclusion: Molar tubes with conventional mesh base design bonded with Transbond XT showed greater shear bond strength than molar tubes with modified mesh base design. Molar tubes with modified mesh base design showed a greater survival rate than molar tubes with conventional mesh base design.
Keywords: Shear bond strength, Molar tubes, Universal testing machine.