Dramatic osteonecrosis of the jaw associated with oral bisphosphonates, periodontitis, and dental implant removal

Enhanced PDGFR/Wnt/β-catenin activity of mesenchymal stem cells with high migration ability rescue bone loss of osteoporosis

Osteoporosis is a widespread disease characterized by bone mass loss and microarchitectural deterioration. The significant side effects of clinical drugs make mesenchymal stem cells (MSCs)-based therapy gain increasing focus in the treatment of osteoporosis. MSCs need to migrate to the site of damage and undergo differentiation in order to participate in the subsequent bone repair process. Therefore, the homing ability of MSCs may be related to the repair ability. Here, we proposed a novel method to screen MSCs with high migration capacity and confirmed that these MSCs exhibited higher osteogenic differentiation ability both in vivo and in vitro. Further researches indicated that MSCs with high migration ability could partly rescue the bone loss of ovarectomized (OVX) rats. Higher expression of Platelet-derived growth factors receptor β- (PDGFRβ) and more nuclear transduction of β-catenin in MSCs with high migration ability may be responsible for biological functions. This article may provide a method to improve the efficacy of MSCs-based therapy in the clinic.

Proposal for a preventive protocol for medication-related osteonecrosis of the jaw

Background

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse reaction experienced by some patients exposed to certain drugs (antiresorptives such as bisphosphonates or denosumab, and antiangiogenic drugs). From a review of the literature it appears that there is no uniform criterion when selecting preventive measures; these vary according to author. Likewise, the measures recommended are usually general, so that in few cases they result in specific actions to be applied depending on the different variables involved such as the type of drug used, the duration of its application, the underlying pathology, the presence or absence of risk factors, etc. The aim of this study has been to design a preventive protocol which can be easily applied in any clinic or by any dental care service.

Material and Methods

We undertook an exhaustive literature review to find any articles related to the topic of study, namely, preventive measures for medication-related osteonecrosis of the jaw, on the one hand generically and on the other focusing on dental implant treatment. The most part the criteria of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. From 3946 items, we selected a total of 21 items.

Results

From the analysis of the selected articles, several protocols have been developed that are easy to apply in a dental clinic.: Protocol 1. Before starting treatment with antiresorptives (Patients who are going to be treated for osteoporosis / Patients who are going to be treated for cancer). Protocol 2. Once treatment is initiated with antiresorptives (Patients being treated for osteoporosis / Patients being treated for cancer).

Conclusions

The application of these protocols requires an interdisciplinary team which can handle the various treatments and apply the measures contained in them. Along with a team of well-educated and trained dentists, it is equally important to maintain contact with the medical team involved in the treatment of the underlying pathology, especially rheumatologists, oncologists, internists and gynaecologists. All the above requires a great staff learning and organization effort, continuous training and coordination of the whole team involved in the preventive management of these patients.

Key words:Medication-related osteonecrosis of the jaw, clinical protocols, clinical guidelines, prevention.

Dental implants as risk factors for patients with medication-related osteonecrosis of the jaws (MRONJ)

An increasing number of patients with medication-related osteonecrosis of the jaws (MRONJ) has recently been reported. It is still being debated whether the presence or placement of dental implants can lead to MRONJ, so the aim of this study was to find out whether dental implants are a risk factor for MRONJ. From January 2003-January 2019 180 patients with MRONJ were seen at the Leiden University Medical Center. Luxating moments for the onset of MRONJ were calculated retrospectively. We collected clinical data and details of antiresorptive medication and found 22 patients with both dental implants and MRONJ. In 18 patients the implants were in the region of the MRONJ and they were included in this study, 14 who had had implants before using antiresorptive drugs and four who had had antiresorptive drugs before or at the time that the implants were placed. The median times between the placement of implants and the diagnosis of MRONJ in these two groups were 24 months and 6 months, respectively. Among the 47 implants, 30 were located in the necrotic region, and all 30 were either lost spontaneously or had to be removed during treatment of MRONJ. Our results show an increased risk for developing MRONJ in patients with dental implants. Both peri-implantitis around previously placed implants, and insertion of dental implants, are risk factors. Prevention of peri-implantitis and caution when inserting dental implants in patients who take antiresorptive medication are therefore important.

Treatment of Bisphosphonate-Related Osteonecrosis of the Jaw With Plasma Rich in Growth Factors After Dental Implant Surgery: A Case Report

Oral bisphosphonates are commonly used to improve bone density in patients who suffer from a variety of pathologies. However, they have also been known to cause bisphosphonate-related osteonecrosis of the jaws (BRONJ). The aim of this clinical case presentation is to (1) determine whether the currently recommended length of time that oral bisphosphonates should be discontinued, before performing dental implant surgery, is sufficient to prevent BRONJ and (2) to describe an alternative treatment for BRONJ. A 65-year-old female patient developed BRONJ after receiving mandibular dental implants 5 months after discontinuing alendronic acid (Fosamax). The BRONJ was treated by surgical osteotomy and plasma rich in growth factors (PRGF), and the patient was followed up with biweekly examinations, which included 0.2% chlorhexidine mouthwashes and removal of any remaining necrotic bone. The dental implants were loaded 41 weeks after surgery and followed up with periapical radiographs and implant stability quotient measurements at 3, 6, 12, and 24 months postloading. Although the Association of Oral and Maxillofacial Surgeons protocols for suspension of presurgical oral bisphosphonates were followed, this patient still developed BRONJ after implant surgery. While a multitude of treatments have been described in the literature, there is not enough scientific evidence to support any one treatment. Based on this clinical case, it can be concluded that the potential adverse effects of oral bisphosphonates on the jaws could be greater than expected and that treatment with PRGF produces promising results, although more long-term studies are necessary to confirm these findings.

The Dental Management of Patients at Risk of Medication-Related Osteonecrosis of the Jaw: New Paradigm of Primary Prevention

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse reaction of antiresorptive and antiangiogenic agents; it is a potentially painful and debilitating condition that can considerably affect the quality of life of patients. Furthermore, even if its epidemiology and pathogenesis have still not been fully clarified, several risk factors related to MRONJ have been recognized in prevention protocols. Three main risk factors are as follows: (i) the type of ONJ-related medications: antiresorptive (e.g., Bisphosphonates, Denosumab) and antiangiogenic drugs (e.g., Bevacizumab, Sunitinib); (ii) the category of patient at MRONJ risk: cancer versus non-cancer patient; (iii) the typologies and timing of dental treatments (e.g., before, during, or after the drug administration). The aim of this paper is to describe the new paradigm by the Italian Society of Oral Pathology and Medicine (SIPMO) on preventive dental management in patients at risk of MRONJ, prior to and during/after the administration of the aforementioned ONJ-related drugs. In reducing the risk of MRONJ, dentists and oral hygienists are key figures in applying a correct protocol of primary prevention for pre-treatment and in-treatment patients. However, the necessity of a multidisciplinary standardized approach, with a sustained dialogue among specialists involved, should be always adopted in order to improve the efficacy of preventive strategies and to ameliorate the patient's quality of life.

Development of Antiresorptive Agent-Related Osteonecrosis of the Jaw After Dental Implant Removal: A Case Report

Dental implant treatment is a highly predictable therapy, but when potentially lethal symptoms or complications occur, dentists must remove the implant fixture. Recently, reports on antiresorptive agent-related osteonecrosis of the jaw have increased in the field of dental implants, although the relationship between dental implant treatment and antiresorptive agents remains unclear. Here, we report a case of antiresorptive agent-related osteonecrosis of the jaw that developed after dental implant removal. A 67-year-old Japanese woman with a medical history of osteoporosis and 7 years of oral bisphosphonate treatment was referred to our hospital with a chief complaint of painful right mandibular bone exposure. A family dentist removed the dental implants from the right mandible using a trephine drill without flap elevation in August 2016. However, the healing was impaired; she was referred to our hospital 3 months after the procedure. We performed a sequestrectomy of the mandible under general anesthesia. In conclusion, this patient's course has two important implications: First, the removal of dental implants from patients who are prescribed oral bisphosphonates for long durations can cause antiresorptive agent-related osteonecrosis of the jaw. Second, meticulous procedures are required to prevent and treat the development of antiresorptive agent-related osteonecrosis of the jaw after dental implant removal.

Mesenchymal Stem Cells: Cell Fate Decision to Osteoblast or Adipocyte and Application in Osteoporosis Treatment

Osteoporosis is a progressive skeletal disease characterized by decreased bone mass and degraded bone microstructure, which leads to increased bone fragility and risks of bone fracture. Osteoporosis is generally age related and has become a major disease of the world. Uncovering the molecular mechanisms underlying osteoporosis and developing effective prevention and therapy methods has great significance for human health. Mesenchymal stem cells (MSCs) are multipotent cells capable of differentiating into osteoblasts, adipocytes, or chondrocytes, and have become the favorite source of cell-based therapy. Evidence shows that during osteoporosis, a shift of the cell differentiation of MSCs to adipocytes rather than osteoblasts partly contributes to osteoporosis. Thus, uncovering the molecular mechanisms of the osteoblast or adipocyte differentiation of MSCs will provide more understanding of MSCs and perhaps new methods of osteoporosis treatment. The MSCs have been applied to both preclinical and clinical studies in osteoporosis treatment. Here, we review the recent advances in understanding the molecular mechanisms regulating osteoblast differentiation and adipocyte differentiation of MSCs and highlight the therapeutic application studies of MSCs in osteoporosis treatment. This will provide researchers with new insights into the development and treatment of osteoporosis.

Occurrence and risk indicators of medication-related osteonecrosis of the jaw after dental extraction: a systematic review and meta-analysis

AIMS

The primary objective was to assess the occurrence rate of Medication-Related OsteoNecrosis of the Jaw (MRONJ) after dental extraction in patients treated with Antiresorptive Drugs (ARD) for OsteoPorosis (OP) or for oncological reasons. The secondary objective was to compare the extraction techniques regarding the occurrence of MRONJ.

MATERIALS AND METHODS

A systematic search in PubMed/MEDLINE, EMBASE and LILACS databases was performed. Prospective studies considering human patients treated with ARD and providing information regarding the occurrence of MRONJ after dental extraction were selected. Meta-analysis for incidence of MRONJ at the patient level was performed. The effect of administration route and surgical technique on MRONJ was evaluated.

RESULTS

The risk of MRONJ after dental extraction was significantly higher in patients treated with ARD for oncological reasons (3.2%) than in those treated with per os ARD for OP (0.15%) (p < 0.0001). Dental extraction performed with adjusted extraction protocols decreased significantly MRONJ development. Potential risk indicators such as concomitant medications and pre-existing osteomyelitis were identified.

CONCLUSION

The risk of MRONJ after dental extraction in patients treated with ARD exists, especially in patients treated for oncologic reasons. This risk tends to decrease with adjusted extraction protocols.

Effect of a hierarchical hybrid micro/nanorough strontium-loaded surface on osseointegration in osteoporosis

This study evaluated the effect of a hierarchical hybrid micro/nanorough titanium strontium-loaded (MNT-Sr) surface on osseointegration under osteoporotic conditions.