As implant dentistry continues to evolve as an office based sub-specialty, it is now rare for patients to have hospital surgery for reconstructive dental bone grafting procedures prior to or during dental implant placement. New biological materials are used for office based regenerative surgery and are considered a replacement for conventional autogenous block grafts. They fall into the category of bone substitutes.
Bone substitutes area a significant component of reconstructive dental implant surgery. While implants are the most expensive disposable item in any implant practice, bone substitutes are a solid second. However, the attention clinicians give to the biology of these materials, studies on their effectiveness in regenerating bone, or long-term success following implant placement is often lacking.
Many clinicians will be attentive to details about an implant’s surface treatment and life-table analysis of success rates, and then ignore studies about the long-term effectiveness of implants following alveolar socket grafting with a certain bone substitute. Consider this: if a sinus is augmented with a certain bone substitute, but bone doesn’t form after a 6-month healing period, that time is lost forever. Selecting a bone substitute that performs as advertised in a given situation is very important. So what questions should one ask when faced with a decision about selecting a bone substitute: There are at least five important questions to consider.
1. What is the intended use for the product
The material must be FDA approved (if in the U.S.) for the intended indication. They always list all indications in the product’s package insert. If not listed, the company probably doesn’t have the appropriate studies for the specific indication, or they cannot verify scientific validity.
2. Does the product resorb
If the product acts either via an osteoinductive or osteoconductive mechanism, the material will ultimately be replaced by new bone. In this regard, the material must have a documented and published “resorptive curve.” This is not just a spot trephine biopsy at, say, six months documenting the presence of bone. It should be a time course study (usually at three-month intervals) demonstrating precent new bone and percent bone substitute remaining at each time point. Ideally, one wants implants in new bone, not the old grafting material.
3. Does the product remodel adjacent to dental implants
An implant placed adjacent to a grafting material is expected to undergo a remodeling process just as normal bone will. This will influence osseointegration and loading parameters. Some grafting material have slower resorption/remodeling times. Loading of dental implants will be affected. Therefore, studies validating a bone substitute’s remodeling properties adjacent to titanium are vital.
4. Is the product packaged in cc’s or grams
Bone substitute must be cost effective for your practice. Normally, surgeons place bone grafting materials based on volumes (cc’s), yet some companies package materials based on weight (in grams). This practice makes it hard to estimate the volume required (after all, surgeons don’t weigh materials out in grams). Companies should be challenged to provide equivalent product weights in cc’s. This will allow a product comparison based on cost per cc.
5. Can the company give you peer reviewed articles and studies, in English, supporting their claims for their product
While articles published in a foreign language can add substantially to a product’s clinical validity, evaluation by English speaking clinicians can be difficult unless the articles are in English.
Many bone substitutes are currently on the market, and more are on the way. Selecting the appropriate one for a given situation can be a challenging task. Hopefully, these questions can help streamline the process of selecting the bone substitute that are right for your office.