Correction of an alveolar ridge deficiency using a sugar cross-linked hydroxyl-apatite sponge – A clinical and histological analysis

Background

OSSIX Bone is a resorbable sponge-like matrix of hydroxyapatite and collagen cross-linked by sugar. Developed to augment hard tissue in periodontal and implant surgeries, it is powered by GLYMATRIX® technology which Mimics the natural collagen cycle in our body by utilizing a naturally occurring nontoxic sugar as the cross-linking agent

Aim/Hypothesis

The aim of this case report is to evaluate a novel collagen-based bone grafting material in lateral and vertical bone augmentation of an edentulous ridge prior to implant placement.

Material and Methods

A 73-year-old female presented with missing teeth #34, 35, 36, 37 (left mandibular premolars and molars) (Fig 1). The teeth were extracted 2 years prior to initial examination. CT scan revealed buccal bone defects in the area of teeth #34 and 35, and vertical bone defect at the area of tooth #37(Fig 2). Following a full thickness flap elevation, horizontal and vertical augmentation was performed using a sugar cross-linked collagen-hydroxyl-apatite sponge (OSSIX® Bone) grafting material, without a barrier membrane (Fig 3). Flaps were released and tension free closure achieved with 5-0 resorbable sutures (Fig 4). A CT-scan was taken at 5 months post-surgery and 3 implants were placed in the augmented ridge (Fig 5). An excisional biopsy was taken from the augmented site during implant placement. Those tissue samples were decalcified and embedded in paraffin, stained with H&E and analyzed by an oral pathologist.

Results

Healing of the augmented site proceeded with small matrix exposure that was epithelialized within two weeks without complications. The first signs of a secondary epithelialization were already detectable at the time of the suture removal 10 days post-op (Fig 6). A CBCT scan that was performed at 5 months showed radio-opaque tissue in the augmented site (Fig 7). Following a full thickness flap elevation, a surface biopsy was obtained, and 3 implants successfully placed. At three months following implants placement, implants were stable and restored (Fig 8). Histological analysis showed ossification pattern with complete remodeling of the hydroxyapatite and collagen matrix sponge into dense mature bone (Fig 9).

Conclusion and Clinical Implications

Correction of an alveolar ridge deficiency prior to the implant placement was successfully performed with a sugar cross-linked collagen-hydroxyl-apatite sponge (OSSIX® Bone) grafting material alone. Histology from the augmented site revealed a unique ossification pattern with complete remodeling of the graft matrix into dense bone. This may offer extended therapeutic options due to its special properties that may go beyond the classic indication spectrum of a bone filler material.