Clinical validation of robot simulation of toothbrushing - comparative plaque removal efficacy
BMC Oral Health
Clinical validation of robot simulation of toothbrushing - comparative plaque removal efficacy
Tomas Lang
Sebastian Staufer
Barbara Jennes
Peter Gaengler 0
0 Faculty of Health, Department of Dentistry, University of Witten/Herdecke , Alfred-Herrhausen-Str. 50, 58448 Witten , Germany
Background: Clinical validation of laboratory toothbrushing tests has important advantages. It was, therefore, the aim to demonstrate correlation of tooth cleaning efficiency of a new robot brushing simulation technique with clinical plaque removal. Methods: Clinical programme: 27 subjects received dental cleaning prior to 3-day-plaque-regrowth-interval. Plaque was stained, photographically documented and scored using planimetrical index. Subjects brushed teeth 33-47 with three techniques (horizontal, rotating, vertical), each for 20s buccally and for 20s orally in 3 consecutive intervals. The force was calibrated, the brushing technique was video supported. Two different brushes were randomly assigned to the subject. Robot programme: Clinical brushing programmes were transfered to a 6-axis-robot. Artificial teeth 33-47 were covered with plaque-simulating substrate. All brushing techniques were repeated 7 times, results were scored according to clinical planimetry. All data underwent statistical analysis by t-test, U-test and multivariate analysis. Results: The individual clinical cleaning patterns are well reproduced by the robot programmes. Differences in plaque removal are statistically significant for the two brushes, reproduced in clinical and robot data. Multivariate analysis confirms the higher cleaning efficiency for anterior teeth and for the buccal sites. Conclusions: The robot tooth brushing simulation programme showed good correlation with clinically standardized tooth brushing. This new robot brushing simulation programme can be used for rapid, reproducible laboratory testing of tooth cleaning.
Toothbrushing; Plaque control; Cleaning efficacy; Robot simulation; Randomized clinical trial; Oral hygiene
-
Background
Plaque removal by manual or powered toothbrushing is still
the most effective preventive method to control gingivitis
manifestation and caries lesion stagnation or progression
[1]. This cornerstone of oral hygiene is supported by
lifelong local applications of different fluoride formulations
and, when needed, of various antibacterial agents.
To motivate consumers oral hygiene behaviour and to
enhance the patients compliance towards the
recommended tooth cleaning efficacy, new toothbrush designs
are permanently developed and tested. In contrast to the
past, no standard toothbrush is dominating the market
today. Preferences concerning handle configuration and
brushhead design differ widely among preventive
caregivers and consumers. Different age groups, patients
disease profiles, patients in special needs etc. require
individual toothbrush models and, consequently, individual
brushing techniques in the frame of contemporary
personalized preventive medicine. New toothbrush models for
this various target groups should remove plaque equally
efficient or better than their predecessors and, therefore,
their plaque removal efficacy needs to be tested prior to
manufacture.
The ultimate goal of such testing would be the outcome
of clinical testing under field conditions by assessing
full mouth plaque removal and gingivitis scores. This
is, however, very time consuming, rather expensive and
difficult to standardize for later comparative
metaanalyses [1]. Therefore, the assessment of in vitro tooth
cleaning efficacy became a real alternative to clinical
trials in testing many different designs and action
modalities of manual and powered toothbrushes. Since
1972 several test environments were developed to test
manual and powered toothbrushes prior to
manufacture or clinical testing. Arnold and Trost were the first
to introduce a simple brushing machine using
horizontal movements on acrylic tooth models covered with a
water-based dye [2]. A more sophisticated equipment
by Nygaard-stby et al. was primarily developed to
measure inter-proximal penetration of the toothbrush
bristles by using a typewriter colour ribbon band to
simulate inter-proximal space during horizontal or
vertical brushing movements with brushing forces
between 2.5 and 10.0 N [3]. Rawls et al. proposed static
and dynamic tests using recommended brushing
techniques on blue ethyl cellulose coated typodont models
at an angulation of 45. Moistened toothbrushes were
applied with weight controlled force between 1.0 and
10.0 N [4]. The interproximal penetration of bristles
was controlled and measured by a high-speed video
camera and a colour removal index. The disadvantage
of the experimental approach was the colour coating of
plastic teeth not simulating the adherence of plaque
biofilms on natural teeth. Therefore, Volpenhein et al.
developed a plaque simulating red coating based on
ethyl ester and copolymer. Manual toothbrushes were
mo (...truncated)