**6.1 Before starting antiresorptive therapy**

Before starting antiresorptive therapy, it is important to make an initial dental examination with a detailed history and radiologically and clinically evaluate the patient's condition. An orthopantomogram is recommended of the radiological techniques. The goal of preventive screening is to remove any potential conditions that could lead to the formation of osteonecrosis during therapy. It is necessary to remove all incurable teeth or teeth with a poor prognosis, cure acute or chronic infections, cysts, tumors and other pathological conditions of the jaw. If the patient has a prosthesis, it is necessary to examine the sharp edges or possible painful areas ("blistering") that may adversely affect the mucosa. If teeth need to be extracted, it is advisable to wait a minimum of three weeks to achieve acceptable soft tissue healing, or preferably four to six weeks to achieve sufficient bone healing before initiating antiresorptive therapy [3].

Patients need to be educated about the risk of developing osteonecrosis, motivate them to strengthen oral hygiene and more frequent control (at least four times a year).

### **6.2 After therapy/during therapy**

Depending on the duration and manner of taking antiresorptive drugs, it is necessary to make a detailed treatment plan that includes a consultation with a competent doctor for possible withdrawal of therapy.

Invasive surgical procedures (extraction, endodontic surgery) are reported as an increased risk of creating necrosis itself. In high-risk patients (high-potency drugs, adjunctive therapy), for the development of osteonecrosis, tooth extraction is not recommended and instead of extraction, endodontic treatment is recommended with root smoothing and cement coating. However, if invasive surgery is required as indicated for severe periodontitis, movable teeth, root fractures, then it is advisable to use the recommended guidelines [3].

A. Oral bisphosphonates.


### B. Denosumabs.

Denosumabs are most commonly taken subcutaneously every six months. If invasive surgery is required, it is recommended to do it three weeks before the next application of the drug itself. It should be in mind that denosumabs are extremely potent drugs for the formation of osteonecrosis, but they, unlike bisphosphonates, are eliminated from the tissues after six months [3].

*Application of Photodynamic Therapy in the Treatment of Osteonecrosis of the Jaw DOI: http://dx.doi.org/10.5772/intechopen.94257*

C. Parenteral bisphosphonates.

The previous recommendation was to discontinue therapy six months before the procedure and three months after, but this is especially difficult in malignant patients (due to the severity of the underlying disease) and discontinuation of therapy has not been scientifically proven to reduce the risk of osteonecrosis. It is recommended that the patient be referred to a specialist institution for the most at-risk group. Poor soft tissue healing should be in mind in patients receiving chemotherapy, especially three to four weeks after chemotherapy when mucositis of the oral mucosa is most common [3].
