Toothbrushing Systematics Index (TSI): A new tool for quantifying systematics in toothbrushing behaviour

Systematics is considered important for effective toothbrushing. A theoretical concept of systematics in toothbrushing and a validated index to quantify it using observational data is suggested. The index consists of three components: completeness (all areas of the dentition reached), isochronicity (all areas brushed equally long) and consistency (avoiding frequent alternations between areas). Toothbrushing should take a sufficient length of time; therefore, this parameter is part of the index value calculation. Quantitative data from video observations were used including the number of changes between areas, number of areas reached, absolute brushing time and brushing time per area. These data were fed into two algorithms that converted the behaviour into two index values (each with values between 0 and 1) and were summed as the Toothbrushing Systematics Index (TSI) value; 0 indicates completely unsystematic and 2 indicates perfectly systematic brushing. The index was developed using theoretical data. The data matrices revealed the highest values when all areas are reached and brushed equally long. Few changes occurred between the areas when the brushing duration was 90 s; the lowest values occurred under opposite conditions. Clinical applicability was tested with data from re-analysed videos from an earlier intervention study aiming to establish a pre-defined toothbrushing sequence. Subjects who fully adopted this sequence had a baseline TSI of 1.30±0.26, which increased to 1.74±0.09 after the intervention (p 0.001). When the participants who only partially adopted the sequence were included, the respective values were 1.25±0.27 and 1.69±0.14 (p 0.001). The suggested new TS-index can cover a variety of clinically meaningful variations of systematic brushing, validly quantifies the changes in toothbrushing systematics and has discriminative power

Toothbrushing Systematics Index (TSI): A new tool for quantifying systematics in toothbrushing behaviour

Systematics is considered important for effective toothbrushing. A theoretical concept of systematics in toothbrushing and a validated index to quantify it using observational data is suggested. The index consists of three components: completeness (all areas of the dentition reached), isochronicity (all areas brushed equally long) and consistency (avoiding frequent alternations between areas). Toothbrushing should take a sufficient length of time; therefore, this parameter is part of the index value calculation. Quantitative data from video observations were used including the number of changes between areas, number of areas reached, absolute brushing time and brushing time per area. These data were fed into two algorithms that converted the behaviour into two index values (each with values between 0 and 1) and were summed as the Toothbrushing Systematics Index (TSI) value; 0 indicates completely unsystematic and 2 indicates perfectly systematic brushing. The index was developed using theoretical data. The data matrices revealed the highest values when all areas are reached and brushed equally long. Few changes occurred between the areas when the brushing duration was 90 s; the lowest values occurred under opposite conditions. Clinical applicability was tested with data from re-analysed videos from an earlier intervention study aiming to establish a pre-defined toothbrushing sequence. Subjects who fully adopted this sequence had a baseline TSI of 1.30±0.26, which increased to 1.74±0.09 after the intervention (p 0.001). When the participants who only partially adopted the sequence were included, the respective values were 1.25±0.27 and 1.69±0.14 (p 0.001). The suggested new TS-index can cover a variety of clinically meaningful variations of systematic brushing, validly quantifies the changes in toothbrushing systematics and has discriminative power

Clinical validation data.

<p>Clinical validation data.</p

Matrix of non-isochronal theoretical data.

<p>Same matrix as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196497#pone.0196497.g003" target="_blank">Fig 3</a> except the brushing was non-isochronal; the areas were reached for different durations. Negative I-values were replaced by zero. There was no change in C-value; however, the maximum I-value decreased to 0.8, thus reflecting the necessity of isochronicity for a very high I-value.</p

Theoretical data set representing complete, isochronal and consistent brushing.

<p>It shows 15 alternations between the areas, with a total brushing duration of 210 seconds; all reachable areas were brushed with an equal brushing duration. Therefore, both I and C values reached their maximum (I = 1 and C = 0.93). The sum is a TSI-value of 1.93, indicating highly systematic brushing. Note that the order in which the areas are reached has no impact. The graph was made with the analysing software INTERACT® (Professional Software for Observational Research, Mangold International GmbH, Arnstorf, Germany).</p

Brushing systematics according to Rateitschak [3].

<p>The sextants (S I—S VI) and the surfaces (oral vestibular, occlusal) should be reached in a defined order, as indicated by the numbers and arrows. The starting point in this systematics is the oral surface in S IV and it ends on the occlusal surface in S III.</p

Clinical validation of TSI.

<p>Results of the C-value and I-value calculation of the clinical validation of the TSI. Dashed lines show the results if all areas are considered and solid lines show the results of the analysis of vestibular and oral areas. The graphs clearly show that the index has a higher discrimination power if only the vestibular and oral surfaces are analysed, and that the I-value shows no change due to instruction if all areas are analysed. The instruction in the last appointment of the control group led to the same increase in index values as the instructions in the other group. Except for the I-values, which were calculated to analyse ‘all’ surfaces, the values of the COMP analysis showed a tendency towards higher index values compared with the CLIN analysis. Note that the x-axis does not intersect the y-axis at the zero position. For clarity, no standard deviations are given; the mean values and standard deviations are given either in the text or in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196497#pone.0196497.t001" target="_blank">Table 1</a>.</p