PTH improves titanium implant fixation more than pamidronate or renutrition in osteopenic rats chronically fed a low protein diet

Abstract

Summary We evaluated the effects of parathyroid hormone (PTH), pamidronate, or renutrition on osseointegration of titanium implants in the proximal tibia of rats subject to prolonged low-protein diets. PTH improved mechanical fixation, microarchitecture, and increased pull-out strength. Pamidronate or renutrition had lesser effects. PTH can thus improve implant osseointegration in protein-malnourished rats. Introduction Protein malnutrition impairs implant osseointegration in rats. PTH and pamidronate prevent deleterious effects of protein restriction introduced just prior to implantation. Whether these treatments improve osseointegration after chronic protein deprivation, i.e., in osteopenic bone at time of implantation, is unknown. We evaluated effects of PTH, pamidronate, or renutrition on resistance to pull-out of titanium rods implanted into the rat tibiae following isocaloric low-protein intake. Methods Forty-one adult female rats received normal or isocaloric low-protein diets. Six weeks later, implants were surgically inserted into proximal tibiae. Following implantation, rats on low-protein diets were treated with PTH (1-34), pamidronate, saline vehicle, or normal protein diets, for another 8 weeks. Tibiae were removed for micro-computerised tomographic morphometry and evaluation of pull-out strength. Results Pull-out strength decreased in rats on isocaloric low-protein diets compared with normal protein group (−33.4%). PTH increased pull-out strength in lowprotein group, even compared to controls from the normal protein group. PTH and pamidronate increased bone volume/tissue volume, bone-to-implant contact, and trabecular thickness, whilst trabecular separation was reduced, with a shift to more plate-like bone surrounding the implants. Conclusions PTH reversed the deleterious effects of longterm protein undernutrition on mechanical fixation and bone microarchitecture and improved implant osseointegration more than pamidronate or renutrition, likely through changes to structure model index.

Teriparatide Versus Alendronate for the Preservation of Bone Mineral Density After Total Hip Arthroplasty – A randomized Controlled Trial

“…On the other hand, teriparatide may be advantageous for efficient osteointegration due to its ability to activate osteoblasts. Indeed, previous animal experimental studies showed the superiority of teriparatide over bisphosphonate in the mechanical fixation of the implant [26] and in the bone volume around the implant [27]. Also, this study revealed that teriparatide treatment caused high levels of the bone-formation marker (P1NP) to be maintained for 1 year after surgery, which may contribute to the efficient biological fixation of the implant.…”

Osseointegration of Innovative Customized Implants in the Tubular Bone (Experimental Study)

“…Mechanical loading on the bone in vivo influences positively the bone mass, promotes the increase of its density and strength, which is confirmed by the data of studying microarchitectures of the lamellar and trabecular bone [4,5,7].…”

“…In particular, such disease as osteoporosis or insufficient dietary intake of protein can negatively affect the quality of the compact bone tissue and impair the process of implant osseointegration as well [3]. And conversely, systemic treatment of osteoporosis can improve osseointegration influencing positively the architectonics and composition of the bone tissue being formed around implants contributing to a greater mechanical strength of the forming bone-implant block [4][5][6].…”

“…Of great importance for osseointegration are factors of mechanical action exerted by the implant itself (or additional), its specific geometry, chemical composition the surface coating, relief, topology and so on [5]. The way of forming surface relief plays an important role as well.…”

An Overview Regarding Contemporary Biomechanical Aspects on Immediate Loading Dental Implants

“…These factors include the bone morphogenetic proteins (BMPs), in particular BMP-2 and BMP-7 or osteogenic protein-1 (OP-1), and growth factors such as platelet-derived growth factor (PDGF), insulin-like growth factor (IGF), and transforming growth factor-beta 1 (TGF‚-1) alone or combined with IGF-1, and TGF (Mavrogenis et al, 2009). Other biological coatings that have been used to improve osseointegration of titanium implants include collagen and other extracellular matrix proteins such as fibronectin and vitronectin (Ku et al, 2005), and systemic administration of pharmacological agents such as ibandronate and human parathyroid hormone (Dayer et al, 2010).…”