Objectives: The aim of this randomised clinical trial was to evaluate the effectiveness of a microdroplet device in combination with a powered toothbrush to prevent proximal gingival inflammation and to determine the long-term adherence to both products in daily proximal hygiene. Methods: 30 participants with gingival inflammation were randomly assigned (n=10) to use: exp. 1: AirFloss Pro filled with water + Sonicare FlexCare+; exp. 2: AirFloss Pro filled with Listerine Zero + Sonicare FlexCare+; and control: dental floss + manual toothbrush for 28 days. Philips provided the Sonic toothbrushes & microdroplet devices and Johnson & Johnson the Listerine Zero. At baseline and 1st recall the papillar bleeding index (PBI) and the Rustogi-modified Navy Plaque Index (RMNPI) were recorded. Patients completed a questionnaire regarding their usual oral hygiene at the first appointment. Additionally, all 30 patients received an AirFloss Ultra device and a Sonicare toothbrush. One year later, oral hygiene parameters were re-evaluated and patients' adherence to their oral hygiene habits was evaluated using a questionnaire. Results: After 28 days, all three groups showed significantly reduced PBI scores. Both test groups showed significantly lower PBI scores than the dental floss control group. After one year, all groups showed lower PBI scores compared to baseline (p0.05). However, PBI scores increased compared to the first recall. 56% of the population still used the microdroplet device; 25% used dental floss. 89% preferred a powered toothbrush compared to 41% at baseline. 11% of the participants practiced proximal care on a daily basis at baseline. After one year, it was at only 15%. Conclusions: Long-term prevention of gingivitis can be achieved using a microdroplet device in combination with a powered toothbrush. The use of the microdroplet device was convenient for patients as after one year more than half of the population preferred the device in their daily oral routine. However, the percentage of patients practicing proximal care only on an irregular basis is still fairly high. Keywords: gingivitis, biofilm, AirFloss, high-velocity microdroplet device, microburst, powered interdental cleaning device, approximal, interdental, adherence, long-term