29: COMPLICATIONS AND FAILURES: TREATMENT AND/OR PREVENTION

CHAPTER 29 COMPLICATIONS AND FAILURES

TREATMENT AND/OR PREVENTION

To understand complications and failures it is necessary to delve into the literature to examine the etiology that generated the problems with the implant. To clarify and understand these concerns better, the author reviewed the literature to ascertain what the etiological factors were. In 1993 Babbush and Shimura reported on the 5-year statistical and clinical observations with IMZ (Attachment International Inc., Burlingame, CA) two-stage osseointegrated implants.1 Of the 1059 implants reviewed over a period of 5 years, the total number of failures was 24 in the maxilla and 4 in the mandible for a total of 28.1 Babbush et al. reported on the titanium plasma-sprayed Swiss screw implant system in the Journal of Oral and Maxillofacial Surgery in 1986.2 The 1991 textbook Implants: Principles and Practices also reported on a large number of cases.3 Wheeler reported an 8-year clinical retrospective study of titanium plasma-sprayed hydroxyapatite-coated implants in 1996.4 Buchs et al. reported on his interim clinical study on threaded hydroxyapatite-coated implants with 5-year postrestoration safety and efficacy.5 Jaffin and Berman reported the excessive loss of Brånemark fixtures in type 4 bone with a 5-year analysis.6 Huerzeler published “Reconstruction of the Severely Resorbed Maxilla with Dental Implants and Augmented Maxillary Sinus: A Five-Year Clinical Investigation” in 1991.7 This was then followed by two papers by Arun Garg, “Complications Associated with Implant Surgical Procedures, Part I: Prevention” and “Complications Associated with Implant Surgical Procedures, Part II: Treatment” in May 2004 (published in Dental Implantology Update).8,9 A series of papers followed, which are documented in the references.1029

imageCategorization of Etiological Factors in Complications and Failures of Implants

After reviewing the literature it was evident to the author that an appropriate categorization of the etiological factors of complications and/or failure could include three main categories: (1) the implant system, (2) the patient, and (3) the doctor (Box 29-1).

Doctor

Doctor failures can be divided into four categories: preoperative, intraoperative, postsurgical, and restorative (Box 29-4).5175

Interoperative

Problems that may be initiated by the doctor during the surgical procedure range from an oversized osteotomy with a “spinner” of the implant or an undersized osteotomy, which would generate excessive pressures in trying to seat the implant. Excessive drill speed and pressure would cause a precipitous rise in the frictional heat, elevating the temperature above 42°-44° C and actually cooking the cytoplasm of the cells. Over time, this would create a necrosis of the surrounding hard tissues. Insufficient irrigation would cause the same potential problem. A sinus perforation that was not recognized or cared for postsurgically could lead to infection and/or lack of osteointegration. Inappropriate bioengineering could lead to inappropriate length, diameter, or number of implants to support the restoration. Additionally, encroachment of the mental foramen, or perforation of the mandibular canal could lead to a variety of neurological problems. Malposition of the implant could result in the inability to restore the implant(s) or a compromised restoration, leading to poor hygiene, breakdown of the hard and soft tissues, and ultimate loss of the system, as well as compromised aesthetics. Mandibular fracture secondary to excessive pressures and forces (Figure 29-1), especially in the severely atrophied mandible, is quite possible (Box 29-6).

imageTreatment Protocol

Based on all of these factors, a treatment protocol was developed more than 10 years ago that has been utilized whenever these patient problems are diagnosed. The first step in the protocol is determination of the etiology of the problem, which then must be reversed or taken care of. Examples include malocclusion, excessive length of cantilever, insufficient support of implants, and loss of soft tissue integrity both in quality and quantity. When any of these signs and symptoms develop the treatment protocol is initiated to determine which of these factors are relevant and what corrective actions to take.

Preoperative antibiotics are usually initiated 2-3 days before the corrective procedure. In most cases penicillin is still the drug of choice in dental alveolar infections unless there is a medical contraindication or the patient is allergic. Whenever possible, the prosthesis should be removed and a full-thickness mucoperiosteal reflection of the tissue should be carried out. There must be a total removal of soft tissue either with ultrasound or hand instruments. The osseous surrounding structures should be recontoured after all granulation and fibrotic tissue is completely eliminated from the area. If purulent exudate is found at this point, then nothing further should be done until the infection is resolved. This has been extremely rare with this protocol because of the presurgical antibiotic treatment.

Once all of the soft tissues have all been removed from the surface of the implant and the osseous structures have been recontoured, a solution of 1% citric acid is used topically on the surface of the implant and surrounding tissues to detoxify the surface. The area is irrigated with saline after 1.5-2 minutes. Monocycline (Arestin, OraPharma, Inc., Warminster, PA) 1 mg. is injected over the entire surface of the implant and surrounding hard tissue. Once again, the area is irrigated to wash away the monocycline after 1-2 minutes. A composite graft composed of platelet-rich plasma (PRP) fabricated with the usual protocol is then combined with a granular high-porosity bone substitute (Algisorb, Osseous Technologies of America, Newport Beach, CA). The mucoperiosteal tissues are then repositioned and sutured with interrupted 4-0 chromic sutures. The patient is followed for approximately 3 months, during which reconsolidation of the surrounding bone is carried out (Box 29-9) (Figures 29-2 through 29-9).

Jan 7, 2015 | Posted by in Implantology | Comments Off on 29: COMPLICATIONS AND FAILURES: TREATMENT AND/OR PREVENTION
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