Original study - ZZI 01/2013

Frame technique using an allogenic bone matrix for simultaneous implantation and horizontal bone augmentation

E. Esser1, C. Schmidt2

Introduction: So far there is no long-term data available which show superiority in the use of a distinctive bone augmentation technique. Therefore, this study reports about first experiences with an allogenic bone matrix for the simultaneous augmentation of horizontal bone deficits in combination with the simultaneous insertion of dental implants.

Material and methods: In 26 patients (14 male, 12 female, average age 57,2 years) with an horizontal bone width of ? 4 mm in an area of at least three adjacent teeth, 106 dental implants (Type: NobelActive) were inserted in 38 locations. A demineralized allogenic bone matrix in combination with allogenic cancellous bone was used for the augmentation of the horizontal bone deficit. After a healing time of 4 to 6 months, the implants were expired and loaded with a fixed or removable denture.

Results: 106 implants were inserted, 86 of them were loaded. 5 implants lacked of osseointegration. Healing complications were observed in one patient. The histologic inspection showed a narrow zone of newly formed bone linked to the allogenic transplant. The gain in bone was stable und showed no resorption tendency so far.

Discussion: The use of allogenic bone for the augmentation of horizontal bone deficits shows a favorable healing tendency and a stable gain in bone volume. These results should be evaluated as first experiences in the sense of a pilot study. The procedure should be limited to the therapy of horizontal bone defects

Keywords: allogenic bone; dental implant; bone augmentation; horizontal bone deficit

 

Citation:

Esser E, Schmidt C: Frame technique using an allogenic bone matrix for simultaneous implantation and horizontal bone augmentation. Z Zahnärztl Implantol 2013;29:49?57.
DOI 10.3238/ZZI.2013.0049?0057

Introduction

So far there are no long-term data showing the superiority of any particular bone augmentation technique in conjunction with dental implant therapy [2]. For horizontal defects, onlay bone grafts using various techniques and materials and expansion procedures have been described. Besides the “classic” autologous bone block and titanium-reinforced ePTFE membrane, it is also possible to use particulate grafts with a stabilizing container effect provided by collagen membranes, cross-linked alloplastic materials or autologous bone frames.

Horizontal augmentation has a much better prognosis than vertical onlay grafts because of the broader application surface and the smaller problems with cover [2]. Implant systems with cutting thread surfaces and flared thread flanks of the wood screw type achieve a high degree of primary stability even when the bone width is greatly reduced, despite massive fenestration [3, 4]. This allows a one-stage procedure with implantation and simultaneous grafting to widen and / or contour the bone in the aesthetically important region.

We have therefore used a “frame technique” with a demineralized allogenic bone matrix for this indication since 01.06.2010 in the form of a pilot study. The target parameter was its clinical effectiveness under three aspects: wound healing, stability of the contouring effect and achievement of a stable implant site when implantation and horizontal augmentation were performed simultaneously. The emphasis was particularly on shortening the operating and treatment times by standardization along with avoidance of secondary morbidity.

 

Material and methods

Since 01.06.2010, 26 patients (14 male, 12 female, average age 57.2 years) with implants in 38 locations were included in the study. The perioperative risk was increased by smoking in 4 patients, and 2 patients had diabetes mellitus.

The indication for a frame technique was a horizontal bone deficit ? 4 mm (Cawood class IV–VI) over an area of
at least 3 adjacent teeth. The exclusion criteria were previous radiotherapy, multiple previous operations in the area, reduced general condition and reservations against allogenic grafts. The planned implantation and augmentation could be performed in all cases. 106 NobelActive implants (Nobel Biocare, Gothenburg, Sweden, diameter 3.5 mm or 4.3 mm, length 10–13 mm) were inserted, sometimes with extreme fenestration. 86 of these implants in 21 patients were
loaded functionally in the meantime by a prosthetic superstructure.

A demineralized allogenic bone matrix (Osteograft, Argon Dental GmbH & Co. KG, Bingen, manufacturer: Deutsches Institut für Zell- und Gewebeersatz GmbH, Berlin; licensed in accordance with the German Medicines Act [AMG]) size 15x50 mm was used as frame. After rehydration in normal saline for 15 to 20 minutes, the material, which is approximately 2 mm thick, is flexible and can be cut so that it can be fitted easily to the contour of the alveolar process and fixed by an osseous fixation screw following onlay of the particulate material from the same manufacturer (Fig. 1a, b).

The implants were generally inserted using a conventional planning template and raising a mucoperiosteal flap. In the case of 11 vertical defects in the posterior maxilla, where bone height was less than < 5 mm, simultaneous sinus floor augmentation was performed through the canine fossa using allogenic cancellous bone granules. The operation site was photographed to show the initial appearance. 42 of the 106 implants revealed extensive fenestrations. With 32 implants, the buccal bone layer was thinner than < 1 mm.

PAGE: 1 | 2 | 3 | 4