Development and clinical evaluation of a personalised whole-mouth plaque removal device based on air-water bubbly jets

Based on the principle of air-water bubbly jets and digital technology, this study aimed to develop a personalised whole-mouth plaque removal device (PRD) for fully automated intraoral plaque control and to evaluate the clinical results. PRDs were designed and fabricated for 18 subjects based on their three-dimensional (3D) dental data and plaque distribution information, followed by self-controlled intraoral plaque removal trials. Four experimental groups and three control groups were set up for the intraoral plaque removal trial. The experimental groups were all cleaned with the PRD using pure water jets, air-water bubbly jets, pure water jets after rinsing with 5% sodium bicarbonate, and air-water bubbly jets after rinsing with 5% sodium bicarbonate. The control groups consisted of habitual manual brushing, manual brushing with the modified Bass method, and single-beam pulsed water jet irrigator to clean the whole mouth. Each subject completed seven test groups in turn, and 3D information of the dentition before and after cleaning were recorded using an intraoral scanner. This trial adopted plaque removal rate (PRR; %) as the evaluation index, and combined with 3D quantitative analysis for plaque measurements on different tooth surfaces as well as Adjacent Zones. The total PRR and PRR in Adjacent Zones for each group were as follows: Experimental group 1 (pure water jets), 45.20 ± 1.84, 37.22 ± 6.17; experimental group 2 (air-water bubbly jets), 65.49 ± 5.17, 58.66 ± 7.95; experimental group 3 (5% sodium bicarbonate + pure water jets), 45.36 ± 5.17, 39.34 ± 5.76; experimental group 4 (5% sodium bicarbonate + air-water bubbly jets), 71.29 ± 5.02, 67.35 ± 5.39; control group 1 (habitual manual brushing), 59.02 ± 5.25, 38.02 ± 7.76; control group 2 (manual brushing with modified Bass method), 78.17 ± 5.31, 70.53 ± 8.62; control group 3 (pulsed water jet irrigator to clean the whole mouth), 32.32 ± 6.32, 21.39 ± 5.49. Statistical analysis showed that air-water bubbly jets were significantly better than pure water jets in removing plaque ( P < 0.001). Adding rinsing with 5% sodium bicarbonate solution in advance improved the effect of air-water bubbly jets in removing plaque ( P < 0.05), but had no significant effect on the pure water jets ( P > 0.05). The plaque removal effect of air-water bubbly jets was overall better than that of habitual brushing ( P < 0.01), and its advantage was more obvious in the Adjacent Zone (defined as the distance of 1 mm from the adjacent contact area to the mesial and distal) ( P < 0.001), but there was still a difference when compared with the modified Bass method of brushing ( P < 0.01). This study constructed an automated plaque control method based on the principle of air-water bubbly jets, which was overall superior to habitual brushing, with its advantages more obvious in the Adjacent Zone. This study established the design process of a personalised whole-mouth PRD, and proposed a plaque control method that is different from conventional tooth-brushing, and verified its clinical effect. • Propose a new plaque control method. • Air-water bubbly jets improve cleaning efficiency. • The use of 3D quantitative analysis.