Table 2 Results of in vivo studies
From: The impact of Zn-doped synthetic polymer materials on bone regeneration: a systematic review
Author/year | Control group | Experimental group | Zn content | Animal model/bone defect preparation | Bone regeneration measurement | Results |
|---|---|---|---|---|---|---|
Ahmadzadeh et al. 2016 [26] | Control HA | Carbonate hydroxyapatite (cHA) and Zn-Mg-HA nanoparticles (mixed in 1:1 wt% ratio) combined with polyvinyl alcohol (PVA) hydrogel to form a composite graft (CZM-HA graft) | 7.85 wt% in Zn-Mg-HA; 1.96 wt% in the CZM-HA graft | Tibia of male New Zealand albino rabbits; right distal tibia; two holes (4 mm diameter, 2 mm depth); two disk-shaped bone grafts (CZM-HA and control) were embedded. | Micro-CT evaluation/bone quantification with the ImageJ software/SEM-EDX analyses/H&E staining | A few Haversian canals were observed in the CZM-HA graft section; only red blood cells (RBC) and immature bone tissue were seen in control graft section. |
Toledano et al. 2020 [27] | SiO2-NP-doped membrane (HOOC-Si-membrane, the membrane was polymer blend [(MMA)1-co-(HEMA)1/(MA)3-co-(HEA)2], comprising 5 wt% of SiO2 nanoparticles) | a. SiO2-NP-doped membrane functionalized with Zn (Zn-HOOC-Si-membrane, 3 μg Zn/mg membrane) b. SiO2-NP-doped membrane functionalized with Dox (Dox-HOOC-Si-membrane, 76.2 μg Dox/mg membrane) | 0.3 wt% in the Zn-HOOC-Si-membrane | Skull of New Zealand-breed experimentation white rabbits; each side of the skull midline; four bone defects (8 mm diameter, 3 mm depth); randomly allocated membrane of each three groups was used for three bone defects, the fourth was not covered. | Micro-CT evaluation/bone quantification with the ImageJ software/von Kossa silver nitrate stain/toluidine blue staining/fluorescence morphometric studies of the deposition of calcein | Bony bridging processes were observed in the Zn-HOOC-Si-membrane group, while in other groups, the bone only regenerated at the defect edge, without evidence of bridging. |
Liang et al. 2020 [24] | PLGA/CPC scaffold, fixed at 3/17 by weight | a. PLGA/CPC-Si scaffold (2.6 wt% of CaSiO3) b. PLGA/CPC-Zn scaffold (15 wt% of Zn-TCP) c. PLGA/CPC-Si/Zn scaffold (5 wt% of Zn2SiO4) | 2.6 wt% in PLGA/CPC-Zn scaffold; 2.9 wt% in PLGA/CPC-Si/Zn scaffold | Femur of SD rats; two femurs of each rat; cylindrical defects (2 mm diameter, 5 mm height); different scaffolds were implanted into each side. | Micro-CT evaluation/H&E staining/Masson’s trichrome staining | Compared to other 3 groups, the PLGA/CPC-Si/Zn scaffolds yielded a substantial increase in the amount of regenerated bone volume. |
Toledano et al. 2020 [28] | Control nanostructured membranes (Ms, a novel polymer blend polymethylmethacrylate (PMMA)) | a. Ms. loaded with calcium (1.5 μg Ca/mg Ms) b. Ms. loaded with zinc (3 μg Zn/mg Ms) c. Ms. loaded with TiO2 nanoparticles (6% of TiO2 nanoparticles) d. Ms. loaded with human recombinant bone-morphogenetic protein 2 (1.0 μg of protein) | 0.3 wt% in Ms. loaded with zinc group | Skull of New Zealand-breed experimentation white rabbits; each side of the skull midline; six bone defects (6 mm diameter, 3 mm depth); randomly assigned membrane was used for five bone defects, the sixth was left uncovered. | Micro-CT evaluation/bone quantification with the ImageJ software/von Kossa silver nitrate stain/toluidine blue staining/fluorescence morphometric studies of the deposition of calcein | Zn-Ms produced the highest amount of new bone among groups and showed a bridge-like network between the areas of the new bone. |