The topic of osteoporosis and some of its complications that we’ve seen in dentistry with certain of the drugs used to treat it has been a topic of much debate recently. Here is a quick framework of reference and some suggestions.
Osteoporosis is a condition in which the bones lose calcium, becoming thinner and more prone to fracture. An ongoing process called bone remodeling, in which old areas of damaged bone are removed (“resorbed”) and replaced with new structurally-intact bone, is normal for adults. Under ideal circumstances, these two processes — bone resorption and bone formation — are balanced. Living bones are not like the dry bones of skeletons you see in a museum, which are static and unchanging. Many things can change the balance between normal bone resorption and formation. In osteoporosis, the balance is tipped toward resorption, so more bone is removed than is replaced, resulting in a gradual decrease in the bone density over the years. In recent years, oral (taken by mouth) drugs in a class known as bisphosphonates have been widely used to treat osteoporosis. They act by slowing the excessive bone resorption, establishing a better balance between resorption and formation and increasing bone density.
But we’ve noticed something different in the bone of the jaws. In rare cases, a long-term user of a bisphosphonate drug may develop a complication called osteonecrosis (bone death), in which isolated areas of the jaw bone lose their vitality and die. For such an individual, tooth removal or any kind of oral surgery involving the jaw bone must be carried out with care. Expert opinion recommends that bisphosphonate treatment be stopped for three months or more prior to surgery, if possible.
The cause of osteonecrosis is not well understood, but it appears that the people at greatest risk are those with underlying cancers who have received relatively high-dose, intravenous bisphosphonate treatment, typically given every month over an extended time. The risk of osteonecrosis with relatively low-dose, oral treatment — as is used for the prevention and treatment of osteoporosis — has not been firmly established, but appears to be much smaller.
Bisphosphonates belong to a class of drugs which inhibit osteoclast action and thus the resorption of bone. This works well for maintaining good bone density (since the resorption cycle is being interrupted), however it can have disastrous consequences following bone surgery. Bone will undergo a very structured healing response after surgery, which includes remodelling and turnover. Osteoclasts play a very important part in this remodelling cycle of the healing phase. If the osteoclast action is interrupted, osteonecrosis (bone cell death) may be a consequence. Now not every regiment of bisphosphonates is a significant risk factor for post surgical osteonecrosis. Up until very recently we have only haphazardly determined that injectable regiments of bisphosphonates or regiments of oral bisphosphonates for over three years present a definite contraindication to dental implant surgery. Recently however, a test became available, which gives us a much more accurate way of determining the risk factor: The CTx Test.
The CTx test, also known as the serum C-terminal telopeptide test, is a medical blood test that is used to assess the risk of bisphosphonate-induced osteonecrosis of the jaws. C-terminal telopeptide is a marker used to measure bone metabolism. It is a by-product of normal bone metabolism or bone turnover. If the CTx test shows a low value of CTx, then the implication could be that the bone turnover is low, thus the bone is less likely to recover from trauma, such as a tooth extraction or implant placement. According to Marx ( J Oral Maxillofac Surg. 2007 Dec;65(12):2397-410.): “A stratification of relative risk was seen as CTX values lessthan 100 pg/mL representing high risk, CTX values between 100 pg/mL and 150 pg/mL representing moderate risk, and CTX values above 150 pg/mL representing minimal risk. The CTX values were noted to increasebetween 25.9 pg/mL to 26.4 pg/mL for each month of a drug holiday indicating a recovery of bone remodeling and a guideline as to when oral surgical procedures can be accomplished with the least risk.” The latter portion of Marx’s statement implicates that any kind of Oral Surgery (including dental implant placement) could be an option, if a patient is taken off the regiment (under careful observation of his or her physician, of course) for about 3 months and a CTx re-test is taken for verification of new values. If necessary, your dental professional or physician can order this test for you. This test should be taken after 12 hours of fasting.
Another pre-surgical approach is hyperbaric oxygen therapy prior to dental implant placement. Hyperbaric oxygen therapy (HBO) was first proposed as a treatment for cancer and other conditions in the 1960s. At the time, research studies did not achieve any reproducible results, which engendered much skepticism among medical personnel. This skepticism even extended to HBO’s use in treating clinical conditions that it had previously been shown to help. It was not until the 1970′s that surgeons of the head and neck region came to recognize the value of hyperbaric oxygen in treating damage of the maxilla and mandible occurring during radiation treatments. Research into this therapy has since shown HBO to be effective when used in addition to conventional therapies for the prevention and treatment of osteoradionecrosis. There is also evidence to suggest that HBO may be helpful as a therapy for soft tissue injury caused by radiation, as well as restoring tissues and cells damaged by chemotherapy and radiation treatments. It has been in the field of treating osteoradionecrosis that hyperbaric oxygen therapy has seen some of its most dramatic successes.
If you enjoyed this article, there is a good chance you will like these articles from my blog as well:
- “What Is Osteonecrosis of the Jaw“
- “New Treatment Option For Osteonecrosis Of The Jaw“
- “What Are Dental Implants“
- “Dental Implants Information“
- “Answers To Common Questions About Dental Implants“
- “Dental Implant Time Lapse Video“
- “Dental Implant Success Rates”
- “Metal Free Ceramic Dental Implants“
Thanks for Reading !!