<span>Clinical Study on Survival Rate of Short Implants Placed in the Posterior Mandibular Region: Resonance Frequency Analysis</span><span> </span>

Corrêa, Ana Paula

Clinical Study on Survival Rate of Short Implants Placed in the Posterior Mandibular Region: Resonance Frequency Analysis

Ana Paula S. Corrêa MSc, Surgery and clinic Integrated Department Aracatuba Dental School, Univ. Estadual Paulista, UNESP. Araçatuba, SP, Brazil, Araçatuba, Brazil

Thalita P. Queiroz PhD, Health Sciences, Implantology Post Graduation Course, University Center of Araraquara – UNIARA, Araraquara, Brazil

Rogério Margonar PhD, Health Sciences, Implantology Post Graduation Course, University Center of Araraquara – UNIARA, Araraquara, Brazil

Ana P. Faloni PhD, Health Sciences, Implantology Post Graduation Course, University Center of Araraquara – UNIARA, Araraquara, Brazil

Reinhard Gruber PhD, Oral Surgery, School of Dentistry, University of Vienna, Viena, Austria

Wilson R Poi PhD., Surgery and clinic Integrated Department Aracatuba Dental School, Univ. Estadual Paulista, UNESP. Araçatuba, SP, Brazil, Araçatuba, Brazil

Eloá R. Luvizuto PhD, Surgery and clinic Integrated Department Aracatuba Dental School, UNESP-Univ. Estadual Paulista, Araçatuba, Brazil

Short implants are increasingly used, but there is doubt about their performance being similar to that of regular implants. The aim of this study was to compare the mechanical stability of short implants versus regular implants placed in the edentulous posterior mandible. This study was approved by the Ethics Committee on Research with Human Beings, of the University Center of Araraquara – UNIARA (Process No. 1302/11). All patients signed the term of free and informed consent. Twenty-three patients received a total of 48 short implants (5x5.5mm and 5x7mm) and 42 regular implants (4x10mm and 4x11.5mm) in the posterior mandible. Patients who received short implants had less than 10 mm of bone height measured from the bone crest to the outer wall of the mandibular canal. Resonance frequency analysis (RFA) was performed at time intervals T0 (immediately after implant placement), T1 (after 15 days), T2 (after 30 days), T3 (after 60 days), T4 (after 90 days). The survival rate after 90 days was 87.5% for the short implants and 100% for regular implants (p<0.05). There was no significant difference between the implants in time intervals T1, T2, T3 and T4. In T0, the RFA values of 5x5.5 implants were higher than values of 5x7 and 4x11.5 implants (p<0.05). A total of 6 short implants that were placed in 4 patients were lost (3 of 5x5.5mm and 3 of 5x7mm). Three lost implants started with high ISQ values, which progressively decreased. The other three lost implants started with a slightly lower ISQ value, which rose and then began to fall. Survival rate of short implants after 90 days was lower than that of regular implants. However, short implants may be considered a reasonable alternative for rehabilitation of severely resorbed mandibles with reduced height, in order to avoid performing bone reconstruction before implant placement. Patients need to be aware of the reduced survival rate compared with regular implants before implant placement to avoid disappointments.

Keywords:dental implants, atrophy, bone resorption, mandible

References:

Anitua E, Piña L, Begoña L, Orive, G. Long-term retrospective evaluation of short implants in the posterior areas: clinical results after 10-12 years. J Clin Periodontol. 2014;41(4):404-11.
Atieh MA, Alsabeeha NH, Payne AG, de Silva RK, Schwass DS, Duncan WJ. The prognostic accuracy of resonance frequency analysis in predicting failure risk of immediately restored implants. Clin Oral Implants Res. 2014:25(1):29-35.