Microbial Infection Factors: Some bacteria get into all surgical wounds. The chance that they will cause an infection is dependent on their numbers and their pathogenicity. For example, low-virulence common skin bacteria like staphylococcus epidermidis may adhere to an implant surface by the production of a mucoglycan. The tacky film may allow other organisms to colonize the implant site and cause greater infection. If the biologic seal is violated, an inflammatory reaction will occur. Bone resorption around the implant may follow with the fill-in of granulation tissue and subsequent implant mobility. Further infection may occur, pain with mastication, more mobility and finally, the need for surgical removal of the implant.

The use of antibiotics has a role in decreasing the chance of post-operative infection. The organisms most likely to cause intraoral infections are the normal oral flora, both aerobes and anaerobes. A bacteriocidal rather than bacteriostatic antibiotic is preferred as host defenses are less relied upon. Depending on the surgical case, antibiotics may be administered before, during and after surgery for the control of infection.

Implant Infection Factors: Implant materials, while inert, can still be considered a foreign substance and a potential source of infection, especially with the handling of the implant after manufacturing. For example, over the course of about five months following the placement of an endosseous implant, the bone-implant interface heals in a characteristic fashion. Misch describes four stages of healing. The first two stages consist of a loose woven callus followed by a lamellar compaction of bone around the implant. This osteogenic reaction occurs while local immune defenses are initially reduced. Improper handling of the implant during packaging, storing, sterilization or placement may lead to the production of a biofilm at the implant-tissue interface which may lead to tissue necrosis and implant failure.

During the initial and subsequent remodeling and maturation stages of the healing implant, the area is kept unloaded from masticatory forces. This allows for mechanical retention of the implant within bone and for the formation of the biologic seal.

The need for the practice of meticulous oral home care by the patient is obvious, but of grand importance in the control of infection and health of the dental implant. The American Association of Oral and Maxillofacial Surgeons recommends that patients with implants be educated on a sustained, conscientious program of home car. An oral hygiene maintenance regimen for the implant patient is akin to that prescribed for periodontal patients. Patients should be educated to clean the implants just as they would brush and floss natural teeth.

Surgical Factors In The Control Of Infection: The implant surgeon must pay attention to detail. Contrary to a popular adage, the surgeon must "sweat the small stuff." In treatment planning, the amount and quality of available bone is assessed. Thorough knowledge of regional anatomy is mandatory. For example, the location of the greatest amount of attached gingiva in an edentulous patient is evaluated for strut placement in a planned subperiosteal implant.

Or, since most chewing occurs from the first molars forward, the surgeon may plan on the placement of endosseous cylinders to be no further distal than the first molar region. This plan avoids complicated anatomy, tends to heal soundly, is mechanically easier to perform and allows the patient better access for cleaning.

The surgeon must practice universal precautions and aseptic technique. It is a good idea to simply treat all patients as if they were HIV positive. If done, this will limit the possibility of contamination of the surgical site and infection.

Perez-Garcia notes that whether the origin of an infection is within soft tissue or within bone, the clinician must be aware of the route that infections spread. Infections spread via the blood system, the lymphatics and via facial planes. The implantologist must know where implants are located anatomically in relation to facial spaces and the effects of infection on adjacent structures. An example is found when dissecting the posterior alveolar ridge for the preparation of an impression for a subperiosteal implant. All soft tissues are dissected except the mylohyoid muscle attachments. This will prevent direct passage of the spread of bacteria to the mediastinum. This knowledge is gleaned from review of anatomy, treatment planning and good surgical technique.

Sound surgical technique includes proper incisions, sharp incisions, gentle handling of tissues, radiosurgery and trimming of nonviable tissue, good hemostasis, and good suturing technique. This attention to detail will enhance healing and lessen the chance of infection around dental implants.

Summary: Dental implantology provides a unique service to patients. Providing such a service requires two key elements. First, the proper knowledge, training and attention to detail is needed in order to maximize the healing of implants and subsequent rehabilitation of masticatory function. Second, the ability to practice infection control, recognize and assess risk factors and manage problems as they arise is equally important.

While the standard of care for implantology is not entirely clear, the notion of practicing with common sense is clear. All of the above must exist for implant success.