Articular cartilage has a complex structure and metabolism which allow for a proper movement within joints. Nevertheless, several systemically administered pharmacological agents have been proved to improve the anabolic response in the case of cartilage lesions. Alendronate, glucosamine, chondroitin sulfate, hyaluronic acid, collagen hydrolysate, vitamin C, vitamin D, aspirin and strontium ranelate have shown positive results in clinical trials. On the other hand, calcitonin, risedronate, doxycycline, and celecoxib did not slow the progression of cartilage lesions in clinical trials. Other systemic drugs or supplements such as teriparatide, leptin, zoledronic acid, bevacizumab, atorvastatin, omega-3 fatty acid, naringin, MSM, selenium, zinc, magnesium, resveratrol, donepezil, naproxen, etodolac, ursodeoxycholic acid (UDCA), lithium chloride, and rebamipide showed positive results in in vitro and animal studies but clinical trials are needed to confirm the positive impact on cartilage repair. A number of molecules, not currently available on the market, have also shown promising results in cartilage healing, such as licofelone, sclerostin, cyclopamine, cyclodextrin polysulfate, AG-041R, osteoprotegerin, rhMK, β-cryptoxanthine, NF-κb essential modulator binding domain (NBD), TGF-β-neutralizing antibody, osteogenic protein-1 (BMP-7), fibroblast growth factor 2 (FGF2), and RhBMP-2. Currently available systemic drugs that impair cartilage healing are represented by corticosteroids, vitamin A, and fluoroquinolones.

Bone is a complex tissue with unique properties such as high strength and regeneration capabilities while carrying out multiple functions. Bone regeneration occurs both in physiological situations (bone turnover) and in pathological situations (e.g. fractures), being performed by osteoblasts and osteoclasts. If this process is inadequate, fracture nonunion or aseptic loosening of implants occurs and requires a complex treatment. Exogenous factors are currently used to increase bone regeneration process when needed, such as bisphosphonates and vitamin D, but limitations do exist. Cannabinoid system has been shown to have positive effects on bone metabolism. Cannabinoids at bone level mainly act on two receptors called CB-1 and CB-2, but GPR55, GPR119, TPRV1, TPRV4 receptors may also be involved. The CB-2 receptors are found in bone cells at higher levels compared to other receptors. Endocannabinods represented by anandamide and 2-arachidonoylglycerol, can stimulate osteoblast formation, bone formation and osteoclast activity. CB-2 agonists including HU-308, HU-433, JWH133, and JWH015 can stimulate osteoblast proliferation and activity, while CB-2 antagonists such as AM630 and SR144528 can inhibit osteoclast differentiation and function. CB-1 antagonist AM251 has been shown to inhibit osteoclast differentiation and activity, while GPR55 antagonist cannabidiol increases osteoblast activity and decreases osteoclast function. An optimal correlation of dose, duration, moment of action, and affinity can lead to an increased bone regeneration capacity, with important benefits in many pathological situations which involve bone tissue. As adverse reactions of cannabinoids have not been described in patients under controlled medication, cannabinoids can represent future treatment for bone regeneration.

The search for bone reconstruction materials and methods is an ongoing challenge. The aim of this review is to systemically search the available literature concerning the clinical performance of eggshell as a substitute material in guided bone regeneration in oral surgery. Five databases (PubMed, Cochrane, Web of Science, Scopus, and Embase) were searched up to February 2020. Clinical trials that used eggshell as a bone substitute material were included. Animal and in vivo studies were excluded. ROBINS-I was used to evaluate the risk of bias. A total of 840 studies were retrieved, out of which 55 full-text articles were screened. Five studies were finally included: one study showed critical and four serious risk of bias. A total of 74 patients and 88 intervention sites were included in the five studies. Clinical and radiological evaluation showed complete healing during the follow-ups. Statistically significant radiological and clinical evidence of new bone formation was achieved for socket preservation, grafting after third molar extraction, and cystic/apicectomy grafting. One patient with complications was reported. Histological analysis and micro computed tomography confirmed that it promotes bone regeneration. A comparison with synthetic hydroxyapatite showed similar healing characteristics. Within the limitations of the included studies, eggshell can be safely and efficiently used in guided bone regeneration procedures, but more research is needed to completely evaluate the full potential of this material.

Oral lichen planus (OLP) is a chronic inflammatory disease characterized by the occurrence of multiple, symmetrical lesions in the oral cavity. Hepatitis C virus (HCV) infection has been suggested as an etiological factor in OLP. The purpose of this review was to summarize the current literature regarding the treatment of OLP in patients with HCV infection. An electronic search of the PubMed database was conducted until January 2018, using the following keywords: OLP, HCV, corticosteroids, retinoids, immunomodulatory agents, surgical interventions, photochemotherapy, laser therapy, interferon, ribavirin, and direct-acting antivirals. We selected the articles focusing on the clinical features and treatment management of OLP in patients with/without HCV infection. Topical corticosteroids are considered the first-line treatment in OLP. Calcineurin inhibitors or retinoids can be beneficial for recalcitrant OLP lesions. Systemic therapy should be used in the case of extensive and refractory lesions that involve extraoral sites. Surgical intervention is recommended for isolated lesions. In patients with HCV, monotherapy with interferon (IFN)-α may either improve, aggravate or trigger OLP lesions, while combined IFN-α and ribavirin therapy does not significantly influence the progression of lesions. Direct-acting antiviral (DAA) therapy appears to be a promising approach in patients with HCV-related OLP, as it can improve symptoms of both liver disease and OLP, with fewer side effects. Nevertheless, for clinical utility of DAAs in OLP patients, further studies with larger sample sizes, adequate treatment duration, and long term follow-up are required.

Purpose: Bone consolidation after severe trauma is the most challenging task in orthopedic surgery. This study aimed to develop biomimetic composite for coating Ti implants. Afterwards, these implants were tested in vivo to assess bone consolidation in the absence or the presence of high-frequency pulsed electromagnetic short-waves (HF-PESW). Materials: Biomimetic coating was successfully developed using multi-substituted hydroxyapatite (ms-HAP) functionalized with collagen (ms-HAP/COL), embedded into poly-lactic acid (PLA) matrix (ms-HAP/COL@PLA), and subsequently covered with self-assembled COL layer (ms-HAP/COL@PLA/COL, named HAPc). Methods: For in vivo evaluation, 32 Wistar albino rats were used in four groups: control group (CG) with Ti implant; PESW group with Ti implant+HF-PESW; HAPc group with Ti implant coated with HAPc; HAPc+PESW group with Ti implant coated with HAPc+HF-PESW. Left femoral diaphysis was fractured and fixed intramedullary. From the first post-operative day, PESW and HAPc+PESW groups underwent HF-PESW stimulation for 14 consecutive days. Biomimetic coating was characterized by XRD, HR-TEM, SEM, EDX and AFM. Results: Osteogenic markers (ALP and osteocalcin) and micro-computed tomography (CT) analysis (especially bone volume/tissue volume ratio results) indicated at 2 weeks the following group order: HAPc+PESW>HAPc≈PESW (P>0.05) and HAPc+PESW>control (P<0.05), indicating the higher values in HAPc+PESW group compared to CG. The fracture-site bone strength showed, at 2 weeks, the highest average value in HAPc+PESW group. Moreover, histological analysis revealed the most abundant COL fibers assembled in dense bundles in HAPc-PESW group. At 8 weeks, micro-CT indicated higher values only in HAPc+PESW group vs CG (P<0.05), and histological results showed a complete-healed fracture in groups: HAPc+PESW, HAPc and PESW, but with more advanced bone remodeling in HAPc+PESW group. Conclusion: Using Ti implants coated by HAPc jointly with HF-PESW stimulation positively influenced the bone consolidation process, especially in its early phase, thus potentially providing a superior strategy for clinical applications.