Evaluation of parathyroid hormone bound to a synthetic matrix for guided bone regeneration around dental implants: a histomorphometric study in dogs

J Periodontol. 2010 May;81(5):737-47. doi: 10.1902/jop.2010.090562.


Background: A polyethylene glycol (PEG)-based hydrogel matrix covalently bound to a 35-amino acid peptide of parathyroid hormone cystein-PTH 1-34 (cys-PTH 1-34) was shown to enhance bone regeneration around implants. The aim of this study is to test if the addition of an integrin-receptor-binding arginine-glycine-aspartic acid (RGD)-containing peptide at early healing time points improves the performance of the PEG matrix supplemented with cys-PTH 1-34 (PTH) when applied in acute defects around implants at early healing time points (2 and 4 weeks).

Methods: Six dogs received 48 implants. Each side of the mandible was randomly assigned for implantation at day 0 or 2 weeks. A circumferential critical-size defect was created at each site before implantation. Sites were randomly assigned to one of four groups: 1) PEG alone (PEG group), 2) PEG plus RGD (PEG/RGD group), 3) PEG plus PTH (PEG/PTH group), and 4) PEG plus RGD plus PTH (PEG/RGD/PTH group). Dogs were sacrificed 2 weeks after the second surgery, and specimens were obtained for histologic analysis. For the statistical analysis, mixed linear regression with repeated measurements was used, and a Dunnett-Hsu adjustment was made for multiple comparisons.

Results: At 2 weeks, the percentages of new bone formation within the defect were 12.43% for the PEG group, 15.95% for the PEG/RGD group, 15.32% for the PEG/PTH group, and 16.60% for the PEG/RGD/PTH group. At 4 weeks, the percentages of new bone formation within the defect were 30.01% for the PEG group, 27.90% for the PEG/RGD group, 29.89% for the PEG/PTH group, and 27.58% for the PEG/RGD/PTH group. A marginally significant difference (PEG/RGD/PTH group versus PEG group; P = 0.055) was found at 2 weeks but not at 4 weeks. The highest percentage of bone-to-implant contact (BIC) in the defect site at 2 weeks was observed for the PEG/RGD group (8.57%). The BIC after 4 weeks of healing ranged from 11.54% (PEG/RGD/PTH group) to 16.61% (PEG group). No statistically significant differences were observed in BIC.

Conclusions: The effect of binding PTH covalently to a synthetic, RGD-modified PEG hydrogel marginally significantly improved bone formation at 2 weeks of healing compared to the use of PEG alone. Bone regeneration within the defects increased in all groups at week 4 of healing without statistically significant differences.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bone Regeneration / drug effects*
  • Cysteine / therapeutic use*
  • Dental Implants*
  • Dogs
  • Guided Tissue Regeneration, Periodontal / methods*
  • Hydrogel, Polyethylene Glycol Dimethacrylate*
  • Male
  • Mandible / drug effects
  • Mandible / pathology
  • Mandibular Diseases / pathology
  • Mandibular Diseases / surgery
  • Oligopeptides / therapeutic use*
  • Osseointegration / drug effects
  • Osteogenesis / drug effects
  • Parathyroid Hormone / therapeutic use*
  • Peptide Fragments / therapeutic use*
  • Random Allocation
  • Time Factors


  • Dental Implants
  • Oligopeptides
  • Parathyroid Hormone
  • Peptide Fragments
  • Hydrogel, Polyethylene Glycol Dimethacrylate
  • arginyl-glycyl-aspartic acid
  • Cysteine