Posterior Maxilla Pg 7

Treatment of the Maxillary Sinus in the Compromised Patient
A variety of medically compromising conditions may be encountered in patients who lack dentition in the posterior maxilla and seek implant therapy as a means of restoring form and function in that area. Unfortunately, the body of clinical studies evaluating the success of various implant modalities in various categories of compromised patients is limited. Until more definitive evidence emerges, the following set of guidelines may prove useful.
Contraindications
Three conditions are considered by the author to be absolute contraindications for the placement of any type of implant in the posterior maxilla: a recent or imminent course of chemotherapy and radiation, drug or alcoholism addiction, and blood dyscrasias that directly effect bone metabolism.
Chemotherapy and radiotherapy disturb the bone metabolism, suppresses the immune system, and diminishes healing potential. All three elements must function well for osseointegration to succeed. A retrospective study by Wolfaardt et al³⁹ found that the implant loss rate for patients who had had chemotherapy was 21.88 percent. That study also found one reported case in which all eight mandibular implants placed in a patient who had received chemotherapy one day prior to surgery were lost. Although more investigation of the affect of chemotherapy upon osseointegration is needed, the author currently recommends delaying implant therapy for several months after completion of the chemotherapy.
The metabolic and psychological problems exhibited by patients who are addicted to drugs or alcohol, coupled with their tendency to be non-compliant, make them poor candidates for any sort of implants, let alone those in the challenging and compromised posterior maxilla. As for patients with blood dyscrasias such as hemophilia or leukemia, the author believes that the risk of an adverse outcome due to uncontrolled bleeding or compromised healing warrants recommending against any posterior maxillary implant placement.

Indications in compromised conditions

A number of medical conditions may significantly increase the risk of posterior maxillary implant failure when unaddressed. Coupled with appropriate corrective action, however, implant placement in patients with such conditions can enjoy a reasonable likelihood of success. These conditions include diabetes, smoking, severe parafunctional habits, osteoporosis, and Crohn’s disease.

Diabetes

Diabetes has been associated with numerous complications, including an increased incidence of caries⁴⁰ and periodontitis⁴¹, a higher susceptibility to infection^42-44, and slower healing after surgery⁴⁵. However, evidence has accumulated that diabetic patients who effectively control their disease incur a lower risk of various health complications than their uncontrolled cohorts^40,43,46. When Kapur et al compared 37 diabetic patients who received conventional removable mandibular overdentures with 52 individuals who were fitted with implant-supported ones, the researchers concluded that implants could be successfully used in diabetic patients with even low to moderate levels of metabolic control⁴⁷. A 1994 study found a 92.7 percent implant success rate for Type II diabetic patients under acceptable glucose control⁴⁸. And when the author conducted a study of 227 implants in 34 diabetic patients, a survival rate of 94.3 percent was found⁴⁹. This study included 73 implants placed in the posterior maxilla, where the success rate was 94.5 percent.

Implant practitioners should make clear to diabetic patients the importance of achieving adequate metabolic control, along with stressing the need to take all diabetic medications on the day of surgery and maintain them throughout the healing period. A ten-day regime of broad-spectrum antibiotics beginning on the day of surgery is also recommended.

Smoking and parafunctional habits

The deleterious impact of smoking on osseointegration has been well documented^50,51. Furthermore, implants placed in the maxillary posterior of smokers appear to fare worse than those placed in maxillary posterior sites in non-smokers^10,52. Patients should thus be urged to enroll in a smoking cessation program before and after undergoing implant placement.

Patients who find it impossible to stop smoking should be counseled as to the additional risk of implant failure that they may be incurring. Furthermore, they should be advised that utilization of additional implants might compensate for the failure of some fixtures to osseointegrate and thus increase their overall chances for prosthesis success. The author employs a similar strategy when counseling individuals with severe parafunctional habits. Additional biomechanical support has proven effective in counteracting the harmful effects of bruxism and clenching upon the prosthesis supported by osseointegrated implants.

Osteoporosis

Osteoporosis currently threatens the health of 25 million Americans. Of those individuals (80 percent of whom are women), some seven to eight million are estimated to have the disease already, and an additional 17 million have low bone mass and consequently are at increased risk for osteoporosis and the fractures it causes.

Screening for osteoporosis is thus a prudent course when considering placement of implants in the posterior maxilla of post-menopausal females. This should include comprehensive reviews of medical history and family history, regarding bone fractures. Whenever osteoporosis or osteopenia is identified, a program of supplementation should begin immediately. This should include 1200 to 1500 mg of calcium taken three times a day with meals to maximize absorption, as well as a multiple vitamin that includes C and E and between 600 and 800 mg of Vitamin D. Pharmaceutical preparations such as alendronate sodium or raloxifene HCl also should be prescribed.

Osteoporotic patients should be advised about the importance of continuing this therapeutic regime, not only throughout the healing period, but on a continuing basis. Counseling about lifestyle aspects of avoiding osteoporosis such as engaging in weight-bearing exercise and avoiding smoking, caffeine, excessive alcohol, carbonated sodas, and cortical steroids is also recommended.

Crohn’s disease

Crohn’s disease is a serious inflammatory disorder that predominates in the ileum and colon but may occur in any section of the gastrointestinal tract. Some 500,000 cases are estimated to exist in the U.S. alone⁵³.

Because of the potential for involvement of the oral mucosa, the author urges patients with Crohn’s disease to achieve effective control of their condition before undertaking any form of implant therapy. Several categories of drugs constitute the mainstay of treatment for Crohn’s disease today, including antibiotics, immune modifiers, oral and rectal aminosalicylates, and oral and rectal corticosteroids⁵⁴.

Other considerations

Although pregnancy in itself has no adverse impact on the osseointegrative process, the stress of surgery or the use of narcotics for pain relief may potentially compromise the unborn baby. Delay of implant therapy until after the baby is delivered is thus recommended.

One other compromising condition worth noting is that of the psychotic patient. When the psychosis relates to the teeth and/or mouth, as is not uncommon, implant therapy may create complications for both the implant practitioner and for the patient’s psychiatrist.

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