Simon S Jensen1,2, Reinhard Gruber1,3, Daniel Buser1, Dieter D Bosshardt1,4. 1. Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Bern, Switzerland. 2. Department of Oral & Maxillofacial Surgery, Copenhagen University Hospital (Rigshospitalet), Copenhagen Ø, Denmark. 3. Laboratory of Oral Cell Biology, School of Dental Medicine, University of Bern, Bern, Switzerland. 4. Robert K. Schenk Laboratory of Oral Histology, School of Dental Medicine, University of Bern, Bern, Switzerland.
Abstract
OBJECTIVES: The occurrence of multinucleated giant cells (MNGCs) on bone substitute materials has been recognized for a long time. However, there have been no studies linking material characteristics with morphology of the MNGCs. The aim was to analyze the qualitative differences of MNGCs on two commercially available calcium phosphate bone substitute materials retrieved from bone defects. MATERIAL AND METHODS: Six defects were prepared bilaterally in the mandibular body of three mini pigs. The defects were randomly grafted with either deproteinized bovine bone mineral (DBBM) or biphasic calcium phosphate (BCP). After a healing period of four weeks, bone blocks were embedded in LR White resin. Three consecutive sections per defect were analyzed as follows: two with light microscopy using toluidine blue and tartrate-resistant acid phosphatase (TRAP) staining and one with transmission electron microscopy. RESULTS: Multinucleated giant cells appeared on both biomaterials. On BCP, MNGCs had a flat morphology and were not observed in resorption lacunae. On DBBM, the MNGCs appeared more round and were often found in shallow concavities. MNGCs on both biomaterials demonstrated a varying degree of TRAP staining, with a tendency toward higher staining intensity of MNGCs on BCP. At the ultrastructural level, signs of superficial dissolution of BCP together with phagocytosis of minor fragments were observed. MNGCs on the surface of DBBM demonstrated sealing zones and ruffled borders, both features of mature osteoclasts. CONCLUSION: MNGCs demonstrated distinctly different histological features depending on the bone substitute material used. Further research is warranted to understand the clinical implications of these morphological observations.
OBJECTIVES: The occurrence of multinucleated giant cells (MNGCs) on bone substitute materials has been recognized for a long time. However, there have been no studies linking material characteristics with morphology of the MNGCs. The aim was to analyze the qualitative differences of MNGCs on two commercially available calcium phosphate bone substitute materials retrieved from bone defects. MATERIAL AND METHODS: Six defects were prepared bilaterally in the mandibular body of three mini pigs. The defects were randomly grafted with either deproteinized bovine bone mineral (DBBM) or biphasic calcium phosphate (BCP). After a healing period of four weeks, bone blocks were embedded in LR White resin. Three consecutive sections per defect were analyzed as follows: two with light microscopy using toluidine blue and tartrate-resistant acid phosphatase (TRAP) staining and one with transmission electron microscopy. RESULTS: Multinucleated giant cells appeared on both biomaterials. On BCP, MNGCs had a flat morphology and were not observed in resorption lacunae. On DBBM, the MNGCs appeared more round and were often found in shallow concavities. MNGCs on both biomaterials demonstrated a varying degree of TRAP staining, with a tendency toward higher staining intensity of MNGCs on BCP. At the ultrastructural level, signs of superficial dissolution of BCP together with phagocytosis of minor fragments were observed. MNGCs on the surface of DBBM demonstrated sealing zones and ruffled borders, both features of mature osteoclasts. CONCLUSION: MNGCs demonstrated distinctly different histological features depending on the bone substitute material used. Further research is warranted to understand the clinical implications of these morphological observations.
Authors: Paul Humbert; Meadhbh Á Brennan; Noel Davison; Philippe Rosset; Valérie Trichet; Frédéric Blanchard; Pierre Layrolle Journal: Front Immunol Date: 2019-04-02 Impact factor: 7.561
Authors: Ulrike Kuchler; Gabriel Mulinari Dos Santos; Patrick Heimel; Alexandra Stähli; Franz Josef Strauss; Stefan Tangl; Reinhard Gruber Journal: Clin Oral Implants Res Date: 2019-09-30 Impact factor: 5.021