Objectives: The aim of this study was to evaluate by light microscopy analysis the effect of the use of miniaturised piezoelectric tips versus mini‐five area specific curets on calculus removal and postoperative root surface alterations.

Methods: A total of 20 extracted teeth were used. Two square surfaces (5×5 mm) were marked on each root surface with a diamond bur mounted on a high‐speed handpiece. Before and after instrumentation, a series of magnified images (4.2×) of each experimental surface were taken with a standardized approach. According to a randomization list, the two surfaces on each sample were instrumented in a standardised fashion either with a mine‐five curet or a slim piezoelectric tip. The images were processed using an imaging software. Data were summarised as means and standard deviations for the two outcomes (calculus and alterations.) at each time (pre and post) for both of the groups (manual and mechanical).

Results: Both manual and mechanical instrumentation significantly reduced the calculus deposits (p < .001) without significant differences between the two groups. Both manual and mechanical treatments significantly increased alterations (p < .01). There was a statistically significant evidence of a greater increase in alterations from mechanical treatment.

Conclusions: Slim mechanical piezoelectric tips and manual mini‐five area‐specific curets have similar effects on calculus removal. Manual instrumentation results in a more homogeneous postoperative root surface with less root alterations.