Orthodontic Adhesive Clean-Up Methods: Introducing and Evaluating Erbium Laser Technique

Objectives: To quantitatively and qualitatively evaluate five different adhesive clean-up procedures following orthodontic brackets’ de-bonding.
Methods: Sixty human extracted premolar teeth were cleaned, mounted, bonded with brackets using Transbond SEP and Opal Bond MV, placed in a water for 24 hours then brackets removed with de-bonding plier using a shear force. Five groups were tested (twelve teeth each), using one of the five different adhesive clean-up procedures, 2 laser (new) and 3 burs (conventional): 1-Erbium-doped yttrium aluminum garnet (Er:YAG) laser at 200mJ and 20Hz, 2-Er:YAG laser at 305mJ and 10Hz. 3-30-fluted round end tapered tungsten carbide bur at high speed, 4-#8-fluted round tungsten carbide bur at low speed, and 5-round end tapered fine diamond bur at high speed. The profilometry measurements on the Alphastep 200 were used to measure the Arithmetic average roughness (Ra) and Total Indicator Run-out (TIR) for quantitative evaluation and scanning electron microscope (SEM) at 100x and 1000x for qualitative evaluation of teeth surface.
ANOVA and Tukey B were used for statistical quantitative data analysis.


Results: The two laser settings tested produced a statistically higher TIR, Ra, and Time meaning that the laser produced a rougher enamel surface and was less efficient than the rotary instrumentation. There was no statistical difference found between the three bur techniques in regards to surface texture or time. Qualitatively, the 30-fluted carbide bur left the smoothest surface, the #8 round bur produced effects on a smaller surface area of the enamel with scattered gouging, and the diamond bur left deep grooves on all affected surfaces.

Conclusions: The Er:YAG lasers are contraindicated for adhesive removal following orthodontic de-bonding. The round end tapered fine diamond bur at high speed is not recommended. The 30-fluted round end tapered tungsten carbide bur is the recommended method for orthodontic adhesive removal leaving the smoothest enamel surface.