Effect of loading time on marginal bone loss around hydroxyapatite-coated implants.
OBJECTIVE
The objective of this study is compare the rate of marginal bone resorption around hydroxyapatite-coated implants given different loading times in order to evaluate their stability.


METHODS
The study was conducted retrospectively for one year, targeting 41 patients whose treatment areas were the posterior maxilla and the mandible. Osstem TS III HA (Osstem Implant Co., Busan, Korea) and Zimmer TSV-HA (Zimmer Dental, Carlsbad, CA, USA), which employ the new hydroxyapatite coating technique, were used. The patients were divided into two groups - immediate and delayed loading - and the bone level at the time of loading commencement and after one year of loading was measured using periapical radiography. Differences between the groups were evaluated using Mann-Whitney (α=0.05).


RESULTS
For all patients as a single group, the survival rate of the implants was 100%, and the mean marginal bone loss was 0.26±0.59 mm. In comparison of the differences by loading, mean marginal bone loss of 0.32±0.69 mm was recorded for the immediate loading group whereas the delayed loading group had mean marginal bone loss of 0.16±0.42 mm. However, the difference was not significant (P>0.05).


CONCLUSIONS
Within the limited observation period of one year, predictable survival rates can be expected when using immediately loaded hydroxyapatite-coated implants.
Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea. ; School of Dentistry, Seoul National University, Seoul, Korea.
Young-Kyun
YK
Kim
Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea.
Kyo-Jin
KJ
Ahn
Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea.
Pil-Young
PY
Yun
Department of Dental Science, School of Dentistry, Chonnam National University, Gwangju, Korea.
Minkyoung
M
Kim
Department of Dental Science, School of Dentistry, Chonnam National University, Gwangju, Korea.
Hong-So
HS
Yang
Department of Prosthodontics, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea.
Yang-Jin
YJ
Yi
Department of Conservative Dentistry, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea.
Ji-Hyun
JH
Bae
Bone loss; Loading