title: Comparison of dental implant stabilities by impact response and resonance frequencies using artificial bone.
abstract: OBJECTIVE
  We compared implant stability as determined by the peak frequency from the impact response with the implant stability quotient (ISQ) by resonance frequency analysis (RFA) in various artificial bone conditions. The clinical bone conditions were simulated using an artificial bone material with different cortical thicknesses and trabecular densities.
  
  
  METHODS
  The artificial bone material was solid, rigid polyurethane. The polyurethane foam of 0.8g/cm(3) density was used for the cortical bone layer, and that of 0.08, 0.16, 0.24, 0.32, and 0.48g/cm(3) densities for the trabecular bone layer. The cortical bone material of 4 different thicknesses (1.4, 1.6, 1.8, and 2.0mm) was attached to the trabecular bone with varying density. Two types of dental implants (10 and 13mm lengths of 4.0mm diameter) were placed into the artificial bone blocks. An inductive sensor was used to measure the vibration caused by tapping the adapter-implant assembly. The peak frequency of the power spectrum of the impact response was used as the criterion for implant stability. The ISQ value was also measured for the same conditions.
  
  
  RESULTS
  The stability, as measured by peak frequency (SPF) and ISQ value, increased as the trabecular density and the cortical density increased in linear regression analysis. The SPF and ISQ values were highly correlated with each other when the trabecular bone density and cortical bone thickness changed (Pearson correlation=0.90, p<0.01). The linear regression of the SPF with the cortical bone thickness showed higher goodness of fit (R(2) measure) than the ISQ value with the cortical bone thickness. The SPF could differentiate implantation conditions as many as the ISQ value when the trabecular bone density and the cortical density changed. However, the ISQ value was not consistent with the general stability tendency in some conditions.
  
  
  CONCLUSIONS
  The SPF showed better consistency and differentiability with implant stability than the ISQ value by resonance frequency analysis in the various implantation conditions.
authors.affiliation: Interdisciplinary Program in Radiation, Applied Life Science Major, College of Medicine, BK21, and Dental Research Institute, Seoul National University, Republic of Korea.
authors.forename: Dae-Seung
authors.initials: DS
authors.lastname: Kim
authors.affiliation: Interdisciplinary Program in Radiation, Applied Life Science Major, College of Medicine, BK21, and Dental Research Institute, Seoul National University, Republic of Korea.
authors.forename: Woo-Jin
authors.initials: WJ
authors.lastname: Lee
authors.affiliation: Department of Oral and Maxillofacial Radiology, BK21, and Dental Research Institute, School of Dentistry, Seoul National University, Republic of Korea.
authors.forename: Soon-Chul
authors.initials: SC
authors.lastname: Choi
authors.affiliation: Department of Oral and Maxillofacial Radiology, BK21, and Dental Research Institute, School of Dentistry, Seoul National University, Republic of Korea.
authors.forename: Sam-Sun
authors.initials: SS
authors.lastname: Lee
authors.affiliation: Department of Oral and Maxillofacial Radiology, BK21, and Dental Research Institute, School of Dentistry, Seoul National University, Republic of Korea.
authors.forename: Min-Suk
authors.initials: MS
authors.lastname: Heo
authors.affiliation: Department of Oral and Maxillofacial Radiology, BK21, and Dental Research Institute, School of Dentistry, Seoul National University, Republic of Korea.
authors.forename: Kyung-Hoe
authors.initials: KH
authors.lastname: Huh
authors.affiliation: Department of Periodontology and Dental Research Institute, School of Dentistry, Seoul National University, Republic of Korea. Electronic address: periopf@snu.ac.kr.
authors.forename: Tae-Il
authors.initials: TI
authors.lastname: Kim
authors.affiliation: Department of Oral and Maxillofacial Radiology, BK21, and Dental Research Institute, School of Dentistry, Seoul National University, Republic of Korea. Electronic address: wjyi@snu.ac.kr.
authors.forename: Won-Jin
authors.initials: WJ
authors.lastname: Yi
mesh_terms: D015519:Bone Density; D018786:Bone Substitutes; D001842:Bone and Bones / Q000502:physiology; D015921:Dental Implants; D003799:Dental Stress Analysis; D019544:Equipment Failure Analysis; D006801:Humans; D016014:Linear Models; D011140:Polyurethanes; D014732:Vibration
chemical_list: D018786:Bone Substitutes; D015921:Dental Implants; D011140:Polyurethanes
keywords: Impact response; Implant stability; Implant stability quotient; Peak frequency from power spectrum; Resonance frequency analysis