A letter to the editor of Journal of Interdisciplinary Clinical Dentistry (02-01-2022) regarding short implants


The Authors are clarifying two published studies regarding clinical dental implant therapies with short implants. We published our first paper in 2019 [Takeici K, and Kasugai S. Implant treatments of posterior region with short implants (8 or 6 mm length): Clinical results after 3 years. Journal of Biointegration 9(1); 29-39, 2019, available on line from “J-STAGE”]. We published our second paper in 2021 [Takeichi K, and Kasugai S. Single crown restoration with an implant in posterior molar regions: Comparison with long and standard-length implants after 3 years. Journal of Interdisciplinary Clinical Dentistry 2(2), 2021, available on line from “IACD (International Academy of Contemporary Dentistry) Home Page” ].


Both papers, demonstrate clinical effectiveness of short implants in posterior regions, but there are distinct differences between these clinical studies. The first paper included splinted implant cases together with single crown restorations; the second paper focused on single crown restorations. In addition, the period of the clinical study of the second paper is longer than the first paper resulting in more single crown restorations in the second paper. Thus, these two papers are clearly different.

Indeed, short implants are clinically effective even in single crown restorations in posterior regions. However, crown implant ratios are large in most short implant cases. Recent several studies, including our studies, demonstrate that implants can accept large crown implant ratios compared to natural teeth. However, the amount and the directions of the force to the implant should be properly controlled. “Proper occlusion is always important”, which is similar to a natural teeth.

Dr. Kanpei TAKEICHI and Professor Shohei KASUGAI