The effectiveness of an actuator-driven pulsed water jet for the removal of artificial dental calculus: a preliminary study

Abstract

Background: While hand and ultrasonic scalers are the primary tools used for the removal of dental calculus in periodontal treatment, many studies have shown that they also damage the enamel surface. We have developed a novel actuator-driven pulsed water jet (ADPJ) system, which has the ability to selectively remove materials depending on their stiffness. Considering the different material properties between teeth and dental calculus, it might be possible to develop the ADPJ to remove dental calculus without damage to the tooth's enamel surface using a suitable jet pressure. Therefore, the aim of this study was to assess the effectiveness of the ADPJ in removing dental calculus, and the surface features of the teeth after its use. Methods: A total of 93 artificial teeth coated with artificial dental calculus were examined in this study. The weights of 90 teeth were measured before and after the use of ADPJ, which had an applied voltage setting of 150, 200, or 240 V. The three remaining teeth were instrumented with a conventional hand scaler, ultrasonic scaler, or ADPJ (set at 240 V). Damage to the artificial tooth surfaces was evaluated using 5% Evans blue dye under an optical microscope. Furthermore, apatite pellets, which are utilized as experimental substitutes for natural teeth, were assessed after the use of ADPJ and both conventional scalers. Results: The ADPJ significantly reduced the amount of artificial calculus, and the removal rate was dependent on the applied voltage. No damage was observed on the surface of the artificial tooth and apatite pellet following the use of ADPJ, in contrast to the conventional scalers. Conclusions: The results of this study demonstrate the in vitro effectiveness of ADPJ in the removal of dental calculus, without causing damage to tooth surfaces.

Methodological assessment of the reduction of dissemination risk and quantification of debris dispersion during dissection with a surgical aspirator

“…The standoff distance ranged from 1 to 2.5 mm. The basic operating conditions are input voltage 60 V, suction rate 200 mL/min, flow rate 7.6 mL/min, standoff distance 1.5 mm, and frequency 400 Hz [ 6 , 10 ]. No other condition was changed during the investigation of a parameter.…”

Effectiveness of an actuator-driven pulsed water jet for removal of softened carious dentin

“…The ADPJ could be advantageous for selective grinding of structures of arbitrary hardness just by changing the applied voltage, with a commensurate removal effect using a small amount of water due to the discontinuous water flow 12,16) . In addition, the characteristics of water jet system hardly produce heat or result in deformation, strain, or residual stress on the material 16) .…”

“…The ADPJ system was described in detail in our previous study [10][11][12] . Figure 1 shows a photograph (Fig.…”

“…To prevent scattering, part of the irradiated jet is absorbed by the suction pipe. The pulsed water jet peak pressure is positively corrected with the applied voltage, as previously described (R 2 =0.994, p<0.001) 12) .…”

“…In the field of neurosurgery, it has already been applied in brain tumor surgery as a substitute for scalpels 10,11) . We previously developed an ADPJ for dental use (maximum applied voltage, 240 V) with a higher output than that of the previous pulse jet (maximum operating voltage, 140 V) used in the medical field and reported that the effect of removing dental calculus increases depending on the applied voltage, without damaging tooth surfaces 12) . Therefore, the null hypothesis in this study was that a higher output of ADPJ could remove harder carious dentin without damaging the sound dentin.…”