The Internal Sinus Floor Elevation Procedure is Comparable to the Conventional Sinus Floor Elevation Procedure in Highly Atrophic Alveolar Ridges: Results Four Years after Loading in A Randomized, Controlled, Blind Pilot Study

Abstract

To investigate whether endoscopically assisted internal sinusfloor elevation (EIS) is as good as the conventional opensurgical method (CSE) in terms of sufficient bone support forthe placement of dental implants and long-term implantsuccess. A split mouth model whereby 20 dental implants wereinstalled in 10 patients (five female and five male) following EISor CSE. No graft materials were used, only locally harvestedautogenous bone. Both surgical procedures were monitoredendoscopically at the time of implant placement and uponplacement of the healing abutment (three months). Panoramicradiographs were made pre- and postoperative, and after 36months in order to evaluate peri-implant bone. The averagepreoperative maxillary alveolar bone height at the implant site(first molar) was 4 mm. The average gain in bone height was 6mm using EIS and 5.5 mm with CSE respectively. Clinicalparameters revealed sufficient implant stability at the time ofplacement. Three implants failed during the healing period of12 weeks. The overall implant success rate was 85 percent.The overall success rate at the time of implant loading was 100percent. After loading, no further implant failure was observedover a four year period. Sinus floor elevation is a wellestablishedprocedure for augmentation of the atrophicmaxillary posterior region. Our results indicate that EIS is atleast as good as CSE. Endoscopically assisted surgery helpedprevent, diagnose, and manage sinus membrane perforations.After 48 months of loading, the clinical outcomes of the presentstudy showed that EIS and simultaneous implant placementresulted in low intraoperative trauma, sufficient implant stabilityupon placement, low incidence of postoperative symptoms,and a high success rate.