Objectives: Performing proper toothbrushing is a complicated process for children. Therefore, the aim of this study was to investigate the effect of a smartphone app for improving manual toothbrushing via a gravitation sensor. Methods: In this prospective, controlled, single-blinded, randomized clinical trial, 49 children (mean age 5.1 ± 0.6 years, 27 female) were randomly assigned to test (n = 26) and control (n = 23) groups. All children were provided with manual toothbrushes with an integrated gravitation sensor and they received oral health instructions. Only the children of the test group got an additional smartphone app to visualize and reward proper brushing in form and time. At baseline and recalls after 6 and 12 weeks, plaque and gingival indices (QHI, PBI) were recorded for analysis between the two groups. Results: At baseline, there were no significant differences between the test and control group regarding plaque and gingival indices (QHI: 2.36 ± 0.7 and 2.42 ± 0.8; p = 0.94; PBI: 0.42 ± 0.2 and 0.47 ± 0.3; p = 0.59). At the 6- and 12-week recalls, the test group showed statistically ­significantly better oral health indices than the controls (6-week recall, QHI: 0.8 ±0.5 and 1.88 ± 0.9; p < 0.001; PBI: 0.08 ± 0.1 and 0.26 ± 0.2; p < 0.001; 12-week recall, QHI: 0.44 ± 0.5 and 1.49 ± 0.7; p < 0.001; PBI: 0.05 ± 0.18 and 0.21 ± 0.1; p < 0.001). Conclusion: The results highlight the enormous possibilities of a toothbrushing application via the smartphone, at least for medium-term oral hygiene improvement in preschool children and even after excluding the app. The long-term effect should also be investigated to exclude the expected novelty effect.

Background The Hall Technique is a less invasive caries management technique for treating carious primary molars. It has become a routine treatment at specialists’ practices. Aim To retrospectively evaluate the clinical success and survival rates of preformed metal crowns placed on primary molars using the Hall Technique in a Paediatric Dentistry Setting. Design Patient records of children receiving Hall crowns (with or without proximal slicing) between 2011 and 2017 were reviewed. Teeth with no clinical or radiographic evidence of pulp involvement at baseline and at least six months’ follow‐up were included. Kaplan‐Meier survival analyses and Mantel‐Cox statistics were carried out. Results In total, 181 Hall crowns performed in 2‐ to 10‐year‐olds with a mean follow‐up period of 22 months were included for analysis. Mean d3mft/D3MFT was 6.55 ± 3.48/0.18 ± 0.66. The majority of crowns were successful (92.3%; n = 167), four presented at least one minor failure (2.2%; reversible pulpitis, crown lost, or secondary caries) and ten were major failures (5.5%; irreversible pulpitis or abscess). When comparing crowns performed with no tooth preparation to crowns performed with proximal slicing, no differences were observed (P = 0.70, CI = 0.68‐0.83). Conclusion The survival rate and clinical efficacy of Hall crowns were high in a secondary care‐based setting. The HT is an effective and less invasive management option for asymptomatic carious primary molars.