Comparison of Interproximal Reduction Techniques and Proximal Strips: An Atomic Force Microscopic and Confocal Microscopic Study

Abstract

Objective: A vivo study was conducted to evaluate the surface roughness produced by two different methods: hand-held mechanical and air-rotor stripping and also by HORICO and Ortho-Organizer strips (Bengaluru, India), before and after polishing with 3M Sof-Lex Finishing Strips under Atomic Force Microscope. Methodology: Study included 44 proximal surfaces of extracted premolars divided into a control group and 3 experimental groups with 12 surfaces in each. Hand-held mechanical stripping was done by 40 passages of 6 cm long abrasive strips and air-rotor stripping using high-speed air-rotor turbine hand piece. Polishing was done using 3M Sof-Lex finishing strips. Reduced teeth samples were viewed under Atomic Force Microscope and the proximal strips under Confocal microscope for surface roughness. Results: Air-rotor stripping produced statistically significant more surface roughness compared to the mechanical reduction technique ( P = .01). There was no significant difference between the roughnesses produced by 2 different proximal strips. Tooth surface after IPR with polishing had less roughness compared to unpolished surface. There was no mean difference between the wear of proximal strips. Conclusion: The mechanical reduction technique of interproximal surface produces less surface roughness compared to air-rotor stripping. Polishing with 3M Sof-Lex strips after reduction irrespective of the technique and material used gives smoother surface than even normal enamel.

Evaluation of the enamel nano-topography influenced by different techniques of interproximal reduction: An atomic force microscopic study

“…The chemical polishing resulted in higher surface roughness values compared to unpolished reduced surfaces. This finding was also confirmed by a later study that claimed that these polishing disks result in enamel surfaces smoother than untreated enamel (Harish et al, 2020). Therefore, we chose this polishing technique in our study to confirm its validity in restoring enamel surface smoothness.…”

“…This is similar to our results, where the manual strips displayed the least roughness among groups (disk and safe-tipped burs). Similarly, Harish et al (2020) stated that manual stripping caused less surface roughening than air rotor stripping (ARS, burs). On the contrary, earlier research by Kaaouara et al (2019) found that manual IPR strips produce a rough enamel surface, which is more susceptible to caries when compared to the intensive oscillating strips, which leave a smoother enamel surface.…”

“…The mechanical methods are generally preferred as they are more time saving; moreover, it has been claimed that the manual strips result in a rougher enamel surface that favours the accumulation of plaque (Chee et al, 2014; Livas et al, 2013). Mechanical air rotor reduction is preferred as it creates a smoother enamel surface; however, polishing the reduced surface after both techniques eliminates surface roughness and restores enamel integrity, according to the available studies (Harish et al, 2020).…”

“…The roughest surface is produced by air rotor slenderisation followed by the commercially available manual strips. Nevertheless, this roughness can be smoothed more than intact enamel by good post-reduction polishing methods (Harish et al, 2020).…”