[Plaque accumulation at the fitting surface and cleaning status in patients with full-arch implant-supported fixed...

Objective: To observe the plaque accumulation at the fitting surface and oral hygiene status in patients with full-arch implant-supported fixed prostheses, and explore the possible influencing factors. Methods: Twenty-eight patients [17 males and 11 females, (63.0± 10.8) years old] with 40 full-arch implant-supported fixed prostheses (18 maxillary and 22 mandibular) were collected from January 2012 to September 2020 in Department of Implantology, Peking University School and Hospital of Stomatology. Plaque accumulation at the fitting surfaces were evaluated during the follow-up visit after 6 months following definitive prostheses delivery, by analyzing the digital photographs recorded by ImageJ. Meanwhile, the cleanliness of the fitting surface of prostheses and oral hygiene status were recorded. The oral hygiene habits and the patients' satisfaction with the prostheses were investigated by questionnaire, and the difference of plaque accumulation between different cleaning habits of dentures were compared. Results: The debris index of the fitting surface of the 40 full-arch implant-supported fixed prostheses were 3.28±0.75, and the percentage of area covered with plaque was (51.6±19.0)%. The debris index and plaque accumulation of the mandibular prostheses were significantly higher than that of the maxillary prostheses (P<0.05). In most mandibular prostheses (16/22), calculus was attached to the lingual side of the anterior tooth area. The reserved cleaning space of the restoration showed more plaque accumulation than in other parts. There was no significant difference in the percentage of area covered with plaque between groups with different cleaning habits. The satisfaction survey results indicated the "clean" project had a lowest score. Conclusions: The cleanliness of patients with full-arch implant-supported fixed prostheses was poor, and the hygiene status of the mandibular prostheses was worse than that of maxillary, especially in the anterior tooth area of mandibular prostheses. The influence of different cleaning habits on plaque accumulation was not observed.