Brief Clinical StudiesAssessment of Stability of Craniofacial Implants by Resonant Frequency AnalysisIvanjac, Filip DDS; Konstantinović, Vitomir S. MD, PhD; Lazić, Vojkan DDS, PhD; Dordević, Igor DDS, PhD; Ihde, Stefan DDS Author Information *School of Dentistry, Clinic for Maxillofacial Surgery †School of Dentistry, Clinic for Prosthodontics, University of Belgrade, Belgrade, Serbia ‡Private Dental Practice, Montenegro. Address correspondence and reprint requests to Dr Filip Ivanjac, DDS, School of Dentistry, Clinic for Maxillofacial Surgery, Dr Subotića 4, 11000 Belgrade, Serbia; E-mail: [email protected] Received 6 September, 2015 Revised 14 December, 2015 Accepted 4 December, 2015 This prospective study was approved by the ethics committee of School of Dentistry, University of Belgrade (No. 36/14). Part of this research was financed by Grant No. 41008 of the Ministry of Science of Serbia. The authors report no conflicts of interest. Journal of Craniofacial Surgery 27(2):p e185-e189, March 2016. | DOI: 10.1097/SCS.0000000000002443 Buy Metrics Abstract Implant stability is a principal precondition for the success of implant therapy. Extraoral implants (EO) are mainly used for anchoring of maxillofacial epithesis. However, assessment of implant stability is mostly based on principles derived from oral implants. The aim of this study was to investigate clinical stability of EO craniofacial disk implants (single, double, and triple) by resonance frequency analysis at different stages of the bone's healing. Twenty patients with orbital (11), nasal (5), and auricular (4) defects with 50 EO implants placed for epithesis anchorage were included. Implant stability was measured 3 times; after implant placement, at 3 months and at least after 6 months. A significant increase in implant stability values was noted between all of the measurements, except for triple-disk implants between third and sixth months, and screw implants between 0 and third months. Disk implants showed lower implant stability quotient (ISQ) values compared with screw implants. Triple-disk implants showed better stability compared with single and double-disk implants. Based on resonance frequency analysis values, disk implants could be safely loaded when their ISQ values are 38 (single disks), 47 (double disks), and 48 (triple disks). According to resonance frequency analysis, disk implant stability increased over time, which showed good osseointegration and increasing mineralization. Although EO screw implants showed higher ISQ values than disk implants, disk-type implants can be safely loaded even if lower values of stability are measured. © 2016 by Mutaz B. Habal, MD.