According to the American Dental Association, five million dental implants are placed each year in this country alone. In skilled, experienced hands, the procedure has an excellent success rate. How can this be the case, when so many people have oral challenges? Dr. Mark Cruz explains how he addresses special cases at his Dana Point, CA practice, so that most patients can be candidates for this beneficial treatment.
Adequate bone is an essential element of a successful dental implant. When periodontal disease is present, a tooth has been missing for a long time, or due to other causes such as menopause, alcoholism, or certain medical conditions, jawbone diminishes. The process is called bone resorption.
Though you are unaware of it, bone throughout the body is in a constant state of remodeling. The mechanism for this function is truly amazing.
Osteoblasts are a derivative of stem cells. They secrete a matrix of collagen protein fibers, calcium, and phosphate that revitalizes old bone. Most people are aware that weight-bearing exercise – lifting, walking, or running – helps to keep long bones in arms and legs thick and strong. Why? Because the body senses this extra demand for strength and fortifies bone to withstand it. The same thing happens in your mouth. Each time you bite or chew, roots of teeth send signals telling your body, “Hard work is going on here and we need more osteoblasts.”
Osteoclasts are continuously working against osteoblasts. These cells reside on the outer layer of bone. When a tooth is missing, calcium-sensing receptors detect the lack of need for bone in that area. Osteoclasts are activated to resorb calcium and phosphate, releasing it into blood, so that osteoblasts may send the minerals to areas where bone is more acutely needed.
The rate of resorption is unique to each patient, but most bone is lost during the first 18 months after a tooth is lost or extracted and continues throughout life. Eventually bone becomes too fragile to support a dental implant. This presents a potential complication for an implant in the upper arch – it could pierce the sinus cavity.
Building bone is not as simple as drinking milk or taking a mineral supplement. However, modern bone grafting techniques now make dental implants a possibility for most reasonably healthy patients.
In the past, bone graft options were:
Today, most oral bone grafting can be completed with biocompatible synthetic Alloplast grafting material. The formulation is molded into the desired shape and surgically placed where needed to accelerate bone formation with natural growth factors. The graft supplements volume, until it is gradually replaced with natural bone over the course of several months. At this point, planning for placement of the dental implant can begin.
The American Sleep Association reports that about ten percent of adults and up to 15 percent of children are bruxers – they chronically clench and grind their teeth. This unconscious habit has many serious oral health implications. Bruxing can wear, loosen, or fracture a dental implant restoration (the visible crown). The excessive pressure may also inhibit osseointegration – jawbone fusing with the implant to mimic a tooth root.
A prescription occlusal splint dramatically reduces the impact of bruxism on dental implants. This custom-fitted acrylic guard spreads the bite force of nocturnal bruxing more evenly across the entire arch. It also cushions direct force on teeth and implant restorations. Patients who wear a night guard to preserve implant success often derive ancillary benefits – improvement in TMJ problems, reduction in morning headaches and jaw pain, and less wear on natural teeth.