Calculus removal with diamond-coated ultrasonic inserts in vitro

Efficient calculus removal is a primary goal in periodontal therapy. Diamond-coated ultrasonic inserts (DIs) offer promise for improved scaling and were evaluated in vitro.

Extracted human teeth with moderate to severe calculus had areas of calculus ( approximately 5 x 5 mm) delineated with small burs. Each calculus area was treated under 2.5x magnification to the point of visible root cleanliness with sharp Gracey curets (hand instruments [HIs]), plain ultrasonic inserts (PIs), or ultrasonic inserts with fine-grit diamond coating; the latter two were used in a magnetostrictive ultrasonic instrument at a medium power setting. Each curet or insert was used for four teeth and then replaced by a new instrument. The time needed to clean each tooth/surface was recorded. The total area treated and the area of the residual calculus were calculated using an imaging analysis program.

The mean time required for clinical calculus removal was 29.7 seconds for DIs, 91.9 seconds for PIs, and 49.8 seconds for HIs (all P <0.0001 from each other). Overall, the mean percentage of residual calculus was 6.3% for DIs, 5.4% for PIs, and 3.1% for HIs (significant differences between HIs and the other treatments).

In vitro calculus removal was faster with DIs, followed by HIs and PIs. More residual calculus was found with the DIs; however, the 1% to 3% difference (93.7% clean versus 94.6% clean versus 96.9% clean with DIs, PIs, and HIs, respectively) does not seem to be clinically significant.