SINUS LIFT 100% Anorganic Bovine Bone vs. 50% Anorganic Bovine Bone + 50% Autologous Bone

Università degli Studi di Sassari16 enrolled

Overview

Background: Maxillary sinus floor augmentation is a standard surgical procedure to increase bone height in the atrophic posterior maxilla for dental implant placement. In bone reconstructive surgery, in general, autogenous bone is considered as the gold standard, primarily due to its osteogenic potential and remodelling capacity. Bone substitutes are available that can overcome the limitations of autologous bone due to their osteoconductive properties and biocompatibility. Several studies seem to validate these concepts, but further comparative trials are needed. Aim: To compare the outcome of implants inserted in maxillary sinuses augmented with bovine bone grafts vs 50% bovine bone graft and 50% autologous bone according to a lateral approach. Material and Methods: This study was designed as a randomised, controlled, clinical trial. Sixteen partially or fully edentulous patients, 20 sinuses, (four patients have been bilaterally treated) having 1 to 4 mm of residual crestal height below the maxillary sinuses were randomised according to a parallel group design. Sinuses were grafted according to a lateral approach. Group A (10 sinuses) was grafted with 50% anorganic bovine bone (Bio-Oss) and 50% autogenous bone, group B (10 sinuses) was grafted with 100% anorganic bovine bone (Bio-Oss). According with a two stages approach, after 7 months a total of 32 implants (Nobel Replace tapered groovy) were inserted with an insertion torque between 35 and 45 Ncm. At same surgical procedure a sample of bone was harvested for histomorphometric analysis . All implants were delayed loaded with screw retained temporary crowns 3 months after implants insertion and with screw retained definitive crowns 4 months later. Outcome measures were implant survival, biological and prosthetic complications, radiographic marginal bone-level changes, PPD and BOP. Clinical data were collected at baseline 6,12 months. Statistical significance was tested at the 0.05 probability level, and all values were presented as mean and standard deviation.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

Interventions

50% AAB plus 50% autologous boneDEVICE

All patients were evaluated clinically and their medical histories were recorded. Preliminary screening, including the acquisition of intraoral and panoramic radiographs, was performed to evaluate potential patients' eligibility. Patients who met the selection criteria received oral hygiene instructions and debridement, if required, after which bone volumes were analysed using cone-beam computed tomography (CBCT; Imaging Sciences International, Hatfield, PA, USA). A staged approach was carried out at all sites. Thus, sinus lift grafting procedures were followed by implant placement 7-8 months later. Both groups received tapered implants with an anodised surface.

100% AABDEVICE

Eligibility

Sex: ALL

Medical Language ↔ Plain English

Inclusion Criteria: * Need for implant-supported prosthesis in maxillary posterior area. * Need to insert implant in atrophic posterior maxilla, with a residual alveolar bone height 1 4 mm. * ≥ 18 years of age. * Provided written informed consent. * Smokers of fewer than 10 cigarettes per day. * Absence of sinus cyst or active sinusitis. Exclusion Criteria: * General contraindications to implant surgery. * Occluding dentition in the area intended for implant installation * Periodontitis. * Bruxism. * Immunosuppression. * Previous history of irradiation of the head and neck area. * Uncontrolled diabetes. * Heavy smoker (\>10 cigarettes/day). * Poor oral hygiene. * Current or past treatment with bisphosphonates. * Substance abuse. * Psychiatric disorder. * Inability to complete follow-up ≥1 year. * Lactation.

Outcomes

Primary Outcomes

IMPLANT SURVIVAL

The removal of implants was dictated by instability, progressive marginal bone loss, infection, or implant fracture. The stability of individual implants was measured by the prosthodontist at the time of definitive crown delivery (5 months after implant placement) by applying 35 Ncm of removal torque. After 1 year, implant stability was tested manually with two dental mirror handles.

Time frame: up to 12 months

Secondary Outcomes

MARGINAL BONE LEVELS

Peri-implant marginal bone levels were evaluated on intraoral digital radiographs taken with the parallel technique. A blinded radiologist (FG), unaffiliated with the study centre, interpreted all radiographs. The distances from the mesial and distal interproximal bone to the reference point (the horizontal interface between the implant and abutment) were measured with a software tool (NIH Scion Image, ver. 4.0.2, Frederick, MD, USA) calibrated against the space between two threads to the nearest 0.1 mm, and the mean of these two measurements was calculated for each implant. The measurements were recorded with reference to the implant axis.

Time frame: Baseline, 12 months