Comparison of shear bond strength of brackets recycled using micro sandblasting and industrial methods

Abstract

Objective: To evaluate in vitro the shear bond strength of brackets recycled by sandblasting with aluminum oxide particles of different sizes or reconditioned industrially after successive rebonding. Materials and Methods: Eighty brackets were bonded and debonded sequentially three times. After the first debonding, brackets were divided into four groups: (group 1) sandblasting with aluminum oxide particles of 25 m, (group 2) 50 m, and (group 3) 110 m, and (group 4) industrial recycling. Bond strength and adhesive material remaining on debonded bracket bases were evaluated for each successive debond. Results: No significant differences were detected between the four groups following the first recycle (P . .05). After the second recycle, bond strength was significantly greater for the industrially recycled group than the other groups (P , .016). When shear bond strength was compared within each recycling method, the bond strength of sandblasted brackets decreased with the increase of particle size and with each recycle; for the industrially recycled group, no significant differences were detected between the three sequences (P . .016). In the evaluation of bond material remnant, the industrially recycled group left significantly less bond material after successive recycling than the other groups did (P , .016). Within each recycling method, the adhesive remnant decreased significantly after successive debond (P , .016). Conclusions: Industrial recycling obtained better results than sandblasting after three successive debondings. The brackets' shear bond strength decreased as the size of the aluminum oxide particle used for sandblasting increased and as recycling was repeated. (Angle Orthod. 2015;85:461-467.)

Comparison of multiple rebond shear strengths of debonded brackets after preparation with sandblasting and CO2 laser

“…In addition, an increase in bond strength in the third recycling in the sandblast group might be due to an increase in the porosity of the base of the brackets caused by sandblasting used in the present study which is in line with the results of other studies. 1 , 23 In laser groups, a decreasing pattern in SBS from new brackets to 3 times of recycling was noted. Differences in SBS in pre-recycling (new brackets) group and other laser subgroups were significant.…”

“…Employing previous data with a desired power of 90% at a significance level of 5%, 23 - 25 a sample size of 11 pairs was needed to detect a difference of 2.53 between the two means, which was increased to 15 pairs in order to allow for probable losses.…”

A comparative study on effect of different methods of recycling orthodontic brackets on shear bond strength

“…Previous studies have reported that recycling with aming results in shear bond strength below the recommended range of clinical need (4,5,7,8), while recycling with sandblasting gives clinically acceptable shear bond strength. (4,(8)(9)(10)(11)(12)(13)) SBS of brackets recycled by aming with sandblasting was reported much less in a study by Gupta et al (2.05 MPa) (10) and large value (26.94 MPa) was reported in a study by Bansal et al (11) . However, limited studies are available in literature about the effects of recycling orthodontic brackets with ultrasonic cleaning on shear bond strength.…”

A Comparison of Shear Bond Strength Values of Recycled Self-Ligating Ceramic Brackets with a New Ones (An-in Vitro Study)

“…Different methods have been proposed to remove the remaining adhesive from the ceramic bracket base for rebonding [11] . Inoffice methods such as heating methods (direct heating), mechanical methods (sandblasting or using green stone or tungsten carbide bur) [12,13,14] , and recently laser have been used for bracket recycling. Demand for use of laser in orthodontic had increased during the past years [15] .…”