In this pilot study, we investigated the biocompatibility and degradation rate of an extruded Zn–0.8Mg–0.2Sr (wt.%) alloy on a rabbit model. An alloy screw was implanted into one of the tibiae of New Zealand White rabbits. After 120 days, the animals were euthanized. Evaluation included clinical assessment, microCT, histological examination of implants, analyses of the adjacent bone, and assessment of zinc, magnesium, and strontium in vital organs (liver, kidneys, brain). The bone sections with the implanted screw were examined via scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). This method showed that the implant was covered by a thin layer of phosphate-based solid corrosion products with a thickness ranging between 4 and 5 µm. Only negligible changes of the implant volume and area were observed. The degradation was not connected with gas evolution. The screws were fibrointegrated, partially osseointegrated histologically. We observed no inflammatory reaction or bone resorption. Periosteal apposition and formation of new bone with a regular structure were frequently observed near the implant surface. The histological evaluation of the liver, kidneys, and brain showed no toxic changes. The levels of Zn, Mg, and Sr after 120 days in the liver, kidneys, and brain did not exceed the reference values for these elements. The alloy was safe, biocompatible, and well-tolerated.

Wegener's granulomatosis (WG) is a multi-system disease, characterised by the triad of necrotising granulomata affecting the upper and lower respiratory tracts, disseminated vasculitis and glomerulonephritis. Oral lesions are associated with up to 50% of cases, although are rare as a presenting feature. The most common oral lesions associated with WG are ulceration and strawberry gingivitis. We review the literature regarding oral manifestations of WG and present a case of lingual infarction, an extremely rare oral lesion associated with WG, in a severe, rapidly progressive and ultimately fatal form of the disease.

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The increasing incidence of trauma in medicine brings with it new demands on the materials used for the surgical treatment of bone fractures. Titanium, its alloys, and steel are used worldwide in the treatment of skeletal injuries. These metallic materials, although inert, are often removed after the injured bone has healed. The second-stage procedure—the removal of the plates and screws—can overwhelm patients and overload healthcare systems. The development of suitable absorbable metallic materials would help us to overcome these issues. In this experimental study, we analyzed an extruded Zn-0.8Mg-0.2Sr (wt.%) alloy on a rabbit model. From this alloy we developed screws which were implanted into the rabbit tibia. After 120, 240, and 360 days, we tested the toxicity at the site of implantation and also within the vital organs: the liver, kidneys, and brain. The results were compared with a control group, implanted with a Ti-based screw and sacrificed after 360 days. The samples were analyzed using X-ray, micro-CT, and a scanning electron microscope. Chemical analysis revealed only small concentrations of zinc, strontium, and magnesium in the liver, kidneys, and brain. Histologically, the alloy was verified to possess very good biocompatibility after 360 days, without any signs of toxicity at the site of implantation. We did not observe raised levels of Sr, Zn, or Mg in any of the vital organs when compared with the Ti group at 360 days. The material was found to slowly degrade in vivo, forming solid corrosion products on its surface.

Sub-condylar fractures of the temporomandibular joint can be treated by an extraoral or intraoral approach. Trans-masseteric antero-parotid approach (TMAP) is an extraoral approach utilising a retromandibular incision. The authors evaluated patients’ status and any complications of using TMAP from the years 2013–2017. There were 39 patients (44 fractures). When using TMAP, in 43 fractures the fragments were favourably positioned, in one case the position was compromised. Of the complications, postoperative palsy of the facial nerve was reported 6.8% – in all cases this was only temporary. Late occlusion had an equal number of complications (in 2 cases this was as a result of an infectious complication of the wound, and in 2 cases due to resorption of the proximal fragment). Muscular pain and dysfunction of the temporomandibular joint following trauma were observed consistently in 6.8% of patients. Sialocoele, a non-conforming scar, and infectious complications were observed in 4.5% of patients. TMAP allows rapid surgical performance, with a good view for perfect repositioning and fixation of fragments of sub-condylar fractures of the temporomandibular joint. The complications associated with this approach are, for the most part, temporary, the aesthetic handicap of a scar is considered by patients to be acceptable. Overall, it is possible to evaluate retromandibular TMAP as safe, and the authors recommended it for treatment of sub-condylar fractures of the mandible.