Randomized clinical study of injectable dextrin-based hydrogel as a carrier of a synthetic bone substitute

Abstract

Objectives: This study aimed to improve the performance and mode of administration of a glass-reinforced hydroxyapatite synthetic bone substitute, Bonelike by Biosckin® (BL®), by association with a dextrin-based hydrogel, DEXGEL, to achieve an injectable and moldable device named DEXGEL Bone.

Methods: Twelve participants requiring pre-molar tooth extraction and implant placement were enrolled in this study. BL® granules (250-500 µm) were administered to 6 randomized participants whereas the other 6 received DEXGEL Bone. After 6 months, a bone biopsy of the grafted area was collected for histological and histomorphometric evaluation, prior to implant placement. The performance of DEXGEL Bone and BL® treatments on alveolar preservation were further analyzed by computed tomography and Hounsfield density analysis. Primary implant stability was analyzed by implant stability coefficient technique.

Results: The healing of defects was free of any local or systemic complications. Both treatments showed good osseointegration with no signs of adverse reaction. DEXGEL Bone exhibited increased granule resorption (p = 0.029) accompanied by a tendency for more new bone ingrowth (although not statistically significant) compared to the BL® group. The addition of DEXGEL to BL® granules did not compromise bone volume or density, being even beneficial for implant primary stability (p = 0.017).

Conclusions: The hydrogel-reinforced biomaterial exhibited an easier handling, a better defect filling, and benefits in implant stability.

Clinical relevance: This study validates DEXGEL Bone safety and performance as an injectable carrier of granular bone substitutes for alveolar ridge preservation.

Trial registration: European Databank on Medical Devices (EUDAMED) No. CIV-PT-18-01-02,705; Registo Nacional de Estudos Clínicos, RNEC, No. 30122.

Keywords: Alveolar preservation; Dextrin; Injectable hydrogel; Synthetic bone.

Fig. 1

DEXGEL Bone preparation procedure

Fig. 2

Timeline for DEXGEL Bone preparation and handling

Fig. 3

Clinical images illustrating the procedures sequentially ordered from tooth extraction to dental implant placement

Fig. 4

CONSORT flow diagram of this study

Fig. 5

Toluidine blue–stained representative photomicrographs of the grafted site 6 months post-implantation: a DEXGEL Bone group and b BL® group. NB, new bone; BL, BL® remains; CT, connective tissue. Magnification from left to right: a 1 × , 3 × , and 10 × ; b 1 × , 3 × , and 20 ×

Fig. 6

Quantitative histomorphometric results of DEXGEL Bone and Bonelike by Biosckin® (BL®) conditions: total bone (a), new bone formation (b), reminiscent BL® granules (c), and connective tissue (d) 6 months after implantation. Statistical analysis was performed using Student’s t-test (*p < 0.05). Results are shown as mean percentages ± confidence interval (n = 6). Total bone refers to the sum of new bone with granules

Fig. 7

Quantitative bone volume results (cm.³) obtained from computer tomography (CT) analysis, at the implantation time and after 6 months. Results are shown as mean percentages ± confidence interval (n = 6). The differences in bone volume and time-point between the DEXGEL Bone (test) and Bonelike by Biosckin® (BL®, control) groups were analyzed using Student’s t-test (*p < 0.05)

Fig. 8

Implant Stability Quotient (ISQ) results of the DEXGEL Bone and Bonelike® (BL®) groups, upon dental implant placement. Statistical analysis was performed using Student’s t-test (*p < 0.05). Results are shown as mean values ± confidence interval (n = 6)