Performance evaluation of a dental handpiece in simulation of clinical finishing using a novel 2DOF in vitro apparatus

Abstract

This paper reports on the performance evaluation of a dental handpiece in simulation of clinical finishing using a novel two-degrees-of-freedom (2DOF) in vitro apparatus. The instrumented apparatus consisted of a two-dimensional computer-controlled coordinate worktable carrying a dental handpiece, a piezoelectric force dynamometer, and a high-speed data acquisition and signal conditioning system for simulating the clinical operations and monitoring the dental finishing processes. The performance of the dental handpiece was experimentally evaluated with respect to rotational speed, torque, and specific finishing energy under the applied clinical finishing conditions. The results show that the rotational speeds of the dental handpiece decreased by increasing either the depth of cut or the feed rate at a constant clinically applied air pressure and water flowrate. They also decreased when increasing both the tangential and normal finishing forces. The specific finishing energy decreased with an increase in either depth of cut or feed rate, while the finishing torque increased as either the depth of cut or the feed rate was increased. Implications of these results were to provide guidance for proper applications of dental handpieces in clinical practice.

In vitro rapid intraoral adjustment of porcelain prostheses using a high-speed dental handpiece

“…Bur speeds were obtained from frequency responses corresponding to the largest amplitudes of the tangential and normal force data in the frequency domain using a fast Fourier transform [29]. The specific removal energy u, which is defined as the energy expended per unit volume of removed material, is calculated as:…”

“…The detail of the apparatus has been described previously [29]. It consisted of a computer-aided high-speed air-turbine dental handpiece (DENCEN CST61, Shanghai Medical Instruments, China) with a two-degrees-of-freedom movement capability, a piezoelectric force dynamometer (9257A, Kistler, Switzerland), a charge amplifier (5006, Kistler, Switzerland) and a data acquisition system (LMS SCADAS III 305, LMS International, Belgium).…”

Vibration characteristics of dental high-speed turbines and speed-increasing handpieces

“…5 A number of other researchers have also mentioned difficulties in controlling the many parameters when testing handpieces and RCIs. [22][23][24] The authors aim to carry out further investigations with the handpieces fixed using more clinically realistic methods.…”

Subsurface damage induced in dental resurfacing of a feldspar porcelain with coarse diamond burs

“…In vitro computer-assisted dental resurfacing operations were conducted using a novel experimental apparatus (Yin et al, 2006b). During the in vitro resurfacing, the computer-assisted apparatus enabled a dental handpiece to realize precise feed and down feed movements.…”

“…The in vitro dental resurfacing operations were conducted where the depths of cut were in the range 10-50 mm, and feed rates of 15-60 mm/min. The tangential and normal resurfacing forces and bur speed during resurfacing were in-process measured using a force sensor and a high-speed data acquisition system (Yin et al, 2006b). After dental resurfacing, the cross sections of the resurfaced porcelain samples were polished manually using progressively smaller alumina abrasives of 1200, 1500, 2000, 3000, and 5000 mesh sizes and diamond pastes of 1.5 and 0.5 mm, respectively.…”