Success rates and failures of fixed and removable space maintainers after the premature loss of primary molars.

The evidence base for the use of space maintainers is relatively sparce despite being used for decades after the premature loss of primary molars. This study aims to increase the dental evidence base via investigating retrospectively the success rates of prefabricated fixed and removable space maintainers inserted from 2019 to 2021 and followed up until February 2023 at a specialized university clinic and to identify reasons for any reported minor and major failure. The authors hypothesized that there is no significant difference in failure rates between fixed and removable space maintainers inserted after the premature loss of a single primary molar per quadrant.