The slow release of BMP-7 at a low dose accelerates dental implant healing in an osteopenic environment

Abstract

The aim of the present study was to investigate in vivo whether bone morphogenetic protein-7 (BMP-7) was able to promote and accelerate dental implant healing at a low dose in an osteopenic environment by using a delayed drug-release system. Skeletally mature Chinese goats, having physiologically osteopenic (osteoporotic-like) facial bones, served as an animal model. Dental implants were provided with a delayed-release drug-delivery system and BMP-7 was applied at three different dosages. The implants, inserted into healed extraction sockets, were removed 1, 2 and 3 weeks after surgery. Quantification of osseointegration and formation of new bone in the peri- implant space were measured histomorphometrically. Data revealed no evidence of any adverse drug effect at or near the implantation sites. After the first postoperative week, bone neoformation was minimal; after the second week, peri-implant bone formation appeared, particularly in the groups with low dosages of BMP-7. After 3 weeks, new-bone volume was the largest in the group with the lowest (near-physiological) dosage of BMP-7, also showing the highest efficacy of BMP-7. Other dosage or release modes were found to be significantly less effective. BMP-7 was highly efficacious in promoting and accelerating bone formation in the peri-implant space in a hostile osteopenic environment if released by a slow-mode mechanism over time at near physiological activities. Therefore, biological functionalisation of dental implants by a high-power osteogenic factor may improve their healing success in hostile bony environments (osteopenia, osteoporosis, bone atrophy etc.).

Role of BMP-7 on biological parameters osseointegration of dental implants: Preliminary results of a preclinical study

“…Leknes et al (2008) are in agreement with our study and show robust bone formation after 4 weeks and remodeling of newly formed bone with characteristics similar to those of old bone. As in our study, Hunziker et al (2021) in an experimental osteoporotic model, found at the third postoperative week, a significantly higher BIC value in the BMP-7 group compared to the Ti metal surface only control group.…”

“…Finally, it should be noted that the potential of rhBMP-7 to promote bone formation has been evaluated in a wide variety of large preclinical animal models (Phillips et al, 2006;Hunziker et al, 2021;Schierano et al, 2021) and in our study we used an experimental model with comparable bone anatomy and healing to humans and which has been used extensively in research related to maxillofacial surgery and dental implants. The anatomic and physiologic similarities of the pig to humans in terms of size, physiology, and bone biology have contributed to the successful use of this animal to understand and treat various bone situations and our experimental design was based on previous studies with this animal model, which considered the anatomical characteristics of the tibia to be similar to those of the human mandibular bone in terms of cortical/cancellous ratio and bone quality (Okubo et al, 2002;Mardas et al, 2014).…”

Coating Ti6Al4V implants with nanocrystalline diamond functionalized with BMP-7 promotes extracellular matrix mineralization in vitro and faster osseointegration in vivo

“…The functionalization of O-NCD-coated implants with BMP-7 protein further increased the thickness of the newly-formed bone, as was confirmed by both micro-CT and histological analysis in our study. A recent publication has also shown accelerated new bone formation induced by calcium phosphate + BMP-7-coated Ti implants in goats with osteoporotic-like bones within the first month after implantation 91 . Similar results have been reported in some other publications, where BMP-7-modified Ti or Ta implants promoted faster new bone formation in dog jaws or in rabbit femurs, respectively, than the control metallic implants without BMP-7 44 – 46 .…”

The Sympathetic Nervous System in Dental Implantology

“…Thus, oriented to work on BMP, the drugs identified as most effective could be applied to implant surfaces [147], furthermore enriched in bone substitutes [148] or incorporated into membranes [149]. Delayed-release drug-delivery systems are available and would be an additional application [150]. Propranolol is a drug that has been established for many decades with calculable side effects, especially at low doses [134].…”