Oral rehabilitation with dental implants in patients with tooth agenesis: a retrospective study in Helsinki University Hospital, Helsinki, Finland.

Objective: The aims of this retrospective and descriptive study were to investigate oral rehabilitation with dental implants in tooth agenesis patients treated at Helsinki University Hospital, Finland, between 2015 and 2019, and to analyze implant survival and prosthetic complications within the first 2 years.  Material and methods: This study included 72 patients (42 oligodontia and 30 hypodontia). Data concerning general/oral health and implant treatment modalities were retrieved from hospital records.  Results: Patients were mostly systemically healthy nonsmokers with a mean age of 32.3 years at the time of implant placement. Orthodontic treatment was required for 77.7%, and 31.9% underwent also orthognathic surgery. Patients had 6.6 missing teeth on average and received 2.8 implants each, 205 in total. Tissue augmentation was needed in 64.4% of cases. Screw-retained suprastructures, mainly single crowns (76.4%), were used in 95.5% of cases, all with custom abutments. The mean follow-up time was 25.2 months, with one technical and one mechanical complication. No implants were lost.

Conclusions: With multidisciplinary planning and collaboration, replacement of all teeth in tooth agenesis may not be required. In this study, despite an average of 6.6 missing teeth per patient, only 2.8 implants were placed on average.