Morphological, microbiological and clinical evaluation of different mouthwashes for periodontal and peri-implant tissue oral hygiene maintenance: do we really need them?

Abstract

Aim: The success of dental prosthetic rehabilitation relies not only on resistant crowns, but also on the maintenance of periodontal and peri-implant tissue health, which oral hygiene procedures support by keeping microbial load and tissue inflammation low. Chlorhexidine (CHX)-based mouthwashes effectively control oral microbial load, but their prolonged use is associated with side effects, prompting research into alternatives such as those based on umbelliferone. This study aimed to compare, in vitro and clinically, the efficacy of two different mouthwashes in reducing microbial load and their associated side effects. Methods: Thirteen patients undergoing prosthetic rehabilitation on natural and implant abutments were divided into three subgroups: a test group prescribed an umbelliferone-based mouthwash, a positive control group prescribed a chlorhexidine mouthwash, and a negative control group following standard oral hygiene only. Clinical evaluation assessed periodontal status and pigmentation of resin temporary crowns. In vitro evaluation included morphological observation of temporary crowns using optical and electron microscopy for natural-tooth rehabilitations, and microbial evaluation using the Agar Snyder test for implant rehabilitations. Results: Clinical assessment revealed few side effects in both mouthwash groups. Morphological evaluation showed low microbial biofilm organization in both mouthwash groups, with slight qualitative differences between them, while the negative control group displayed an organized matrix network. Microbial analysis showed no microbial metabolic activity in either mouthwash group, with no differences between them. Conclusion: Within the limits of this preliminary study, the umbelliferone-based mouthwash appeared to reduce microbial load comparably to chlorhexidine, with numerically fewer recorded events, suggesting it may represent a promising alternative for the maintenance of oral hygiene in patients undergoing prosthetic rehabilitation. Further studies with larger samples are needed to confirm these findings. Dental hygienists and dentists may play an important role in guiding patients toward correct adherence to daily oral hygiene routines.