Prognostic Research Related to Survival of IMZ Implants at Two Institutes

• Published in: Nihon Hotetsu Shika Gakkai Zasshi Vol. 46; no. 5; pp. 702 - 711
• Main Authors: Tawada, Yasuyuki, Komatsu, Shigeki, Watanabe, Fumihiko, Furukawa, Tatsuya, Takase, Ichiro, Enomoto, Hiroaki, Enomoto, Kotoyo, Hata, Yoshiaki
• Format: Journal Article
• Language: Japanese
• Published: Japan Prosthodontic Society 2002
• Subjects: cumulative survival rate; implant diameter; implant length; IMZ implant; Kaplan-Meier
• ISSN: 0389-5386; 1883-177X; 1883-177X
• DOI: 10.2186/jjps.46.702

Purpose: This study evaluated the prognosis of IMZ implant cases (271 patients, 972 implants) that had been placed over 13 years at two institutions: thehospital attached to the Nippon Dental University School of Dentistry at Niigata (Inst. 1); and Enomoto Dental Office, in Sanjo City (Inst. 2). Methods: Of the 972 implants, 913 had been clinically examined, in 254 patients, withinthe past two years (recall rate 93.7%). The evaluation was performed focusing on: 1) survival rate, 2) maxillomandibular survival rate, and 3) implant survival rate according to implant sizes. Data obtained were analyzed using the Kaplan-Meier method and Life Table Analysis. Results: The following results were obtained. 1. The cumulative survival rate was 96.3% for 5 years, 92.6% for 10 years, and 89.9% for 13 years, for the total of implants at Inst. 1 and 2. 2. Asto the association of implants with the natural teeth, fracture of the natural teeth occurred in 12.1% of connection cases at Inst. 1, and in 6.8% of connectioncases at Inst. 2. All the fractured teeth were non-vital. 3. Analysis of the total of implants recalled at Inst. 1 and 2 showed no significant differences in the survival rate between maxillary and mandibular implants (Breslow-Gehan-Wilcoxon test, p=0.61). 4. Although no significant differences in the survival rate were noted between implants 3.3mm in diameter, and implants 4.0mm in diameter (Logrank test, p=0.51), and there were also no significant diferences among implants 8, 10, 11, 13, and 15mm in length (Logrank test, p=0.45), the removal rate of implants was different according to implant sizes. Regarding the diameter of implants, the rate was 6.9% for 3.3mm, and 3.4% for 4.0mm, showing a higher survival rate with an increased diameter. Regarding the length of implants, the rate was 13.0% for 8mm, 4.4% for 10 and 11mm, 2.0% for 13mm, and 0% for 15mm, showing a higher removal rate for shorter length. Conclusion: As the IMZ implant achieved a long-term high survival rate, this implant is useful for clinical application.