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This study aimed to identify whether there is an ideal concentration for applying ozonized oil (OZ) in the post-exodontic alveoli of senescent rats treated with zoledronate (ZOL). Thirty-five female rats, aged 18 months, were divided into five groups: ZOL; ZOL+OZ500; ZOL+OZ600; ZOL+OZ700; and SAL. The groups treated with ZOL, and other concentrations of OZ received applications at a dose of 100 μg/kg, while the SAL group received saline. After three weeks of ZOL application, the animals underwent extraction of the lower first molar. Subsequently, local therapies were initiated: group ZOL+OZ500 at 500 mEq/kg; ZOL+Z600 at 600 mEq/kg; and ZOL+OZ700 at 700 mEq/kg at baseline, and on days 2 and 4 post-operation. Euthanasia was performed on day 28. The microtomographic parameter of bone volume and histometric data on the area of neoformed bone (NFBT) showed the highest values for the ZOL+OZ600 group (p < 0.05). All OZ groups had smaller areas of non-vital bone than the ZOL group (p < 0.05). The clinical appearance of the operated region showed the alveoli covered with soft tissue, particularly in the OZ groups. All the tested concentrations of OZ were able to prevent and modulate MRONJ. As it presents a greater amount of NFBT, the concentration of 600 mEq/kg seems to be ideal.

Artificial bone grafting materials such as collagen are gaining interest due to the ease of production and implantation. However, collagen must be supplemented with additional coating materials for improved osteointegration. Here, we report room-temperature atomic layer deposition (ALD) of MgO, a novel method to coat collagen membranes with MgO. Characterization techniques such as X-ray photoelectron spectroscopy, Raman spectroscopy, and electron beam dispersion mapping confirm the chemical nature of the film. Scanning electron and atomic force microscopies show the surface topography and morphology of the collagen fibers were not altered during the ALD of MgO. Slow release of magnesium ions promotes bone growth, and we show the deposited MgO film leaches trace amounts of Mg when incubated in phosphate-buffered saline at 37 °C. The coated collagen membrane had a superhydrophilic surface immediately after the deposition of MgO. The film was not toxic to human cells and demonstrated antibacterial properties against bacterial biofilms. Furthermore, in vivo studies performed on calvaria rats showed MgO-coated membranes (200 and 500 ALD) elicit a higher inflammatory response, leading to an increase in angiogenesis and a greater bone formation, mainly for Col-MgO500, compared to uncoated collagen. Based on the characterization of the MgO film and in vitro and in vivo data, the MgO-coated collagen membranes are excellent candidates for guided bone regeneration.