Dental Implants

MARCH 1990, VOL. 51, NO 3

AORN JOURNAL

Dental Implants PERMANENT REPLACEMENT FOR LOST TEETH

Ted E. Mioduski, Jr, DDS; N. Joanne Guinn, RN t is estimated that more than 45 million people in America do not have natural teeth in their maxilla and/or mandible, and another 100 million people are missing one or two teeth.' Evidence suggests that many denture wearers of all age groups report dissatisfaction with removable prostheses. Common problems from denture wear are chronic gingival tissue irritation, hyperplasia, ulcerations, pain during mastication, and difficulty with speech. There also may be an associated increase in the vulnerability to temporal mandibular joint disorders. People who have dentures that are loose, not properly fitted, or whose appearance is not natural may experience self-

I

conscious embarrassment. A prematurely aged look also might result from alveolar ridge loss. With a maxillary denture plate, the wearer may experience an inability to taste food and detect temperature variations in food and beverages that may diminish his or her eating enjoyment. Dental implants may serve as permanent replacements for lost teeth. Replacing lost natural teeth with implants can provide distinct patient benefits that include improved appearance, confidence, and self-esteem; preservation of remaining teeth; improved nutrition and the ability to speak and masticate properly; and elimination of full dentures and partial plates. Dental implants can return the patient's mouth

Ted E. Mioduski, Jr, DDS, is the director of dental implantologv, St Joseph Hospital, Denver, and a clinical assistant professor, University of Colorado School of Dentistq Denver. He also b in private general dentistrypractice in Loveland, Colo. He received his doctor of dental surgery degree from Indiana University, Indianapolis.

N. Joanne Guinn, RN, BS, is an OR staff nurse, McKee Medical Center, Loveland, Colo. She earned her nursing diploma from Mercy School of Nursing of Detroit and her bachelor of science degree in medical sociology and child psychology from Eastern Michigan University, Ypsilanti. 729

MARCH 1990, VOL. 51, NO 3

to its normal contour, comfort, function, and esthetics, regardless of the type of dental disease, atrophy, injury, or atypical development the patient may experience. Dental implants may be used in a variety of situations. Implants may be used to replace a single tooth, thus eliminating the need for a fixed bridge. They may be used to help anchor a denture. Ultimately, implants may eliminate the need for removable partial dentures or full dentures by replacing them with a fixed bridge supported solely by implants.

Types of Implants

I

mplants can be classified as endosteal, subperiosteal, and transosteal. Implants are made of biocompatible metals (eg, pure titanium, titanium alloys, cobalt chronium alloys). They occasionally are coated with a syntheticbone material (eg, hydroxylapatite), or are used in conjunction with synthetic bone grafts (eg, hydroxylapatite, tricalcium phosphate, polymethyl methacrylate) or heterologous freeze-dried demineralized bone grafts to augment the alveolar ridge. Endosteal implants. These implants resemble metal cylindrical screws or flat blades that are placed into the maxilla or mandible. The implants may have small holes in them to allow bone to grow through them and permanently secure the implant to the mandible or maxilla. The number of implants placed depends on bone availability and the number of teeth to be replaced. When implanted in an alveolus that has adequate bone, the cylindrical implants directly attach to bone. This phenomenon is known as osseointegration.Osseointegration, described by P I Branemark, MD, as early as 1952, is the direct structural and functionalconnection of the implant to the bone.*The insertion of endosteal cylindrical implants initially requires a surgical procedure usually performed in a single ofice visit. Implants are completely submerged in the mandible or maxilla and left undisturbed for three to eight months. The implants are invisible beneath the gingiva, and the patient can wear a soft-lined denture

AORN J O U R N A L

during the osseointegration process. Following the healing period, the surgeon uncovers the implants during a second office procedure to verify osseointegration. In the rare instance that one or two implants have not fused with bone, they can be removed and replaced. An additional healing period for new bone strengthening is needed. On subsequent office visits, prosthesis teeth are anchored to the implants via screws or clips. Complete installation of the prosthesis is accomplished with several office visits. The success rate for all types of dental implants may vary with design, but endosteal implants demonstrate the highest predictable long-term success rate.3 Subperiosteal implants. When a patient cannot tolerate a denture and there is insufficient bone for an endosteal implant, subperiosteal implants are used. Subperiosteal implants are placed beneath the periosteum directly onto the alveolar bone. They are used to support a removeable prosthesis and distribute pressure on the tissue and remaining teeth when the patient chews. Advances in computer-assisted design and computer-assisted manufacturing allow the surgeon to replicate the mandible or maxilla on the computer and generate an image that can be used as a guide to fabricate an implant. Thus, the subperiosteal implant may be designed without a separate surgical procedure to expose the patient’s mandible to take a direct impression. Based on various studies, some cases of subperiosteal implants have been functional for 30 years. The average functional longevityfor these implants is 90%for five years, 64%for 10 years, and 54% for 15 years? Transosteal implant. This approach, like a subperiosteal implant, is used to treat patients with severe mandibular alveolar ridge atrophy. The transosteal technique uses a mandibular stabilizing bone plate with retaining posts to stabilize a fullarch, tissue-borne prosthesis. Because of the extent of intraoral and extraoral incisions, this procedure usually is performed in the hospital with general anesthesia. This depends on the individual surgeon’s preference and training. Prosthetic construction can be undertaken within eight to 731

MARCH 1990, VOL. 51, NO 3

AORN JOURNAL

In our experience, approximately 50%of dental implant patients have full-arch replacement; the remainder have between one and eight teeth replaced. 12 weeks after healing is completed. In our experience, approximately 50%of dental implant patients have full-arch replacement; the remainder have between one and eight teeth replaced. There is no limit to the number of implants that can be placed during one procedure. Depending on the patient’s needs, upper and lower arch implants can be accomplished together. Fewer than 5% of patients have both complete maxillary and mandibular replacement. This is because most people can tolerate an upper denture but not a lower denture.

width, and density of the available alveolar bone. Study models are plaster-cast duplicates of the patient’s dentition made from direct impressions of the patient’s teeth and ridges. A psychosocial appraisal must be made to evaluate the patient’s expectations. It is helpful to know why the patient lost his or her original teeth. Implants require the same care as natural teeth, and the patient may have neglected this care with dentures. If the patient views implants as a second chance and acknowledges a commitment to good oral hygiene, the probability of success is enhanced.

Patient Selection

J

udicious patient and implant selection are important. The patient must be a good medical and surgical risk. The surgical and anesthetic risk indicators are considered as with any surgery and are not specific to implant procedures. The medical evaluation may consist of a history and physical, complete blood count, urinanlysis, vital signs, electrocardiogram, and a complete bleeding profile including prothrombin time, partial thromboplastin time, and coagulation studies. The patient must be in good general health with no uncontrolled systemic disease. Bone metabolism problems, such as osteoporosis, must be taken into consideration, particularly because implant patients may be older and more prone to this condition. Patients without full natural dentition for an extended period of time may have considerable bone resorption. Clinical and radiographic examination usually will determine if there is enough bone available to accept implantation. Dental evaluation should include a complete dental history, dental charting, intraoral and extraoral radiographs, intraoral and extraoral photographs, and study models. Dental radiographs include panoramic, occlusal,periapical, and cephalographic views to visualize the height,

The Endosteal Implant Procedure

T

he patient is given either an oral or intravenous antibiotic one to two hours before surgery.The nurse moves the patient into the dental offce operating room or hospital OR, attaches the appropriate monitors (eg, electrocardiogram, blood pressure monitor, pulse oximeter) and drapes him or her. The surgeon administers the selected anesthesia and then injects the local anesthetic. An anesthesiologist is present when general anesthesia is administered. The patient may receive a local anesthetic, a local with IV sedation, or general anesthesia with local, depending on the extent of the procedure. The dental surgeon administers a local anesthetic of 2% lidocaine with 1:1OO,OOO epinephrine for hemostasis at the incisional site. The dosage depends on the extent of the incision and the number of implants being placed. Intravenous sedation with meperidine hydrochloride and diazepam are used to achieve conscious sedation (ie, the patient is sedated, but maintains control of the gag reflex and is responsiveand cooperative). The dental surgeon inserts cheek retractors and positions a bite block. The dental surgeon makes the appropriate 733

MARCH 1990, VOL. 51, NO 3

AORN JOURNAL

Fig 1. Mandible with severely atrophied ridge.

Fig 2. Six endosseous implants uncovered after four months of healing.

Fig 3. Panoramic radiograph after mandibular implant reconstruction.

incision and reflects a full-thickness mucoperiosteal flap to expose the bone site. If necessary, he or she removes alveolar crest irregularities to provide the ideal width and contour to accept the implants. An osteotomy is performed for each selected implant, using special spade drills and trephines that allow both internal and external irrigation with chilled normal saline solution. The dental surgeon uses a high-torque drill with 700 to 1,500 revolutions per minute and copiously irrigates the osteotomy to reduce the possibility of bone injury or necrosis. This technique also enhances the formation of bone necessary to achieve osseointegration. The dental surgeon places the implants into the prepared osteotomies via a screw-in or tap-in motion. He or she sutures gingival tissue to obtain primary closure over the implants.

Postoperative Care

734

T

he patient applies pressure to the surgical site by biting on a 4x4-inch gauze pad for approximately one hour to promote tissue adaptation and minimize hematoma formation. No packing or dressing is required. The patient who undergoes general anesthesia remains in the postoperative care unit between one and three hours depending on his or her responsiveness and alertness. When the patient’s vital signs are stable, he or she is discharged with analgesicsand antibiotics. The patient is instructed to take antibiotics for two weeks postoperatively.The nurse instructs the patient to apply ice for 24 hours to minimize swelling, apply 4x4-inch gauze with pressure for 24 to 48 hours to minimize bleeding, consume

AORN J O U R N A L

MARCH 1990, VOL. 51, NO 3

Fig 4. A top view of mandibular implants. The implants support the prosthesis.

Fig 5. A nonretracted view of a mandibular implants that support the bridge and the opposing maxillary complete denture. only liquids and soft foods for one to two weeks, avoid excessive activity and smoking, and use good oral hygiene. The nurse makes an appointment for the patient to see the dental surgeon one week postoperatively for observation and suture removal. During healing, the patient is monitored periodically and appropriate adjustments are made to his or her existing dentures, if applicable.

Case Study

A

n attractive and outgoing hospital supervisor has worn upper and lower dentures her entire adult life. A severe, long-standing childhood illness prevented the proper development of natural teeth, and all of her teeth were extracted before high school 736

graduation and replaced with full dentures. The patient represents what is sometimes referred to as a “dental cripple” (ie, a patient with severe atrophy of the mandibular alveolar ridge, concomitant physical limitations, and psychological implications). Even though the patient has tolerated a maxillary denture without complaint, the mandibular denture caused impairment of normal function. Figures 1 through 5 show the patient’s mouth before the mandibular endosteal cylindrical implant procedure and its subsequent restoration with a dental prosthesis solely supported by six implants. The patient continues to wear an upper denture. For the first time in years, she is able to comfortably eat any food she desires and be in public with the confidence that her implanted teeth are as secure as natural teeth.

MARCH 1990, VOL. 51, NO 3

-

Summary

I

mplant complications are rare, but they can include nerve injury, bone loss, infection, injury to adjacent teeth and their supporting structures, premature loss of implants or the prosthesis fitted on the implant, bone fracture, and oroantral (ie, mouth, maxillary sinus) and oronasal (ie, mouth, nose) fistulae. Oral implants represent a new technological possibility. Whether it is used to replace a single tooth, several missing teeth, or an entire dentition, dental implants restore the feeling of having one’s own natural teeth. This can improve the patient’s 0 physical and psychological health. Notes 1. D G Smiler, “Implants: Evaluation and treatment planning,” California Dental Association Journal 15 (October 1987) 35. 2. R Adell et al, “A 15-yearstudy of osseointegrated

AORN JOURNAL

implants in the treatment of edentulous jaw,’’ International Journal of Oral Surgery 10 (December 1981) 387-416. 3. T Albrektsson et al, “The long-term efficacy of currently used dental implants: A review and proposed criteria of success,” The International Journal of Oral & Maxillofacial Implants 1 (1986) 11-25. 4. l b R~Lubar, R Katin, “Two-yearclinical results with Core-Vent implants,” abstract of presentation to First International Congress of Preprosthetic Surgery, Palm Springs, Calif, 1985; R A James et al, “Subperiosteal implants,” CaliforniaDental Association Journal 16 (January 1988) 1 0 D Laskin, “Core-Vent implant clinical report: 4-48 month observaton period,” presented at the American Academy of Oral and Maxillofacial Surgeons (AAOMS) National Meeting in New Orleans, 28 September, 1986; L B Shulman, “Surgical considerations in implant dentistry,” Journal of Dental Education 52 (December 1988) 712. Suggested reading Mioduski, T; Coke, J. “Oral implants.” St Joseph Hospital .primary Care Bulletin 3 (Denver: Fall 1988) 25-28.

TUTOPLAST@DURA and FASCIA LATA FASCIA TEMPORALS, COSTAL CARTILAGE, AND AUDITORY OSSICLES Safe, Strong, Convenient Sterile, double-pouch envelope Available in a wide range of sizes Ready to use in 5 to 15 minutes depending on tissue size

Antigen and enzyme free Compact, size-labeled packaging with see-through final envelope

BIODYNAMICS can now provide you with 100 % human tissue grafts: 0 When you cannot use the patient’s own. 0 Processing inlcudes treatment with 3% hydrogen peroxide. A study conducted by Dr. Friedrich Deinhardt of the University of Munich has shown that 3% hydrogen peroxide eliminated the HIV-1 virus. 0 Five year shelf life 0 Rehydrates in 0.9% normal saline 0 Avoid time and expense in doing a secondary procedure to recover autologous graft. 0 Gentle, solvent dehydration does not compromise natural strength of the tissue For more information and for the name of the distributor in your area, please write or call

P

BIODYNAMICS,INC.

6611 Porhrvest Drive Suite 190 Houston, TX 77024

See us at booth number 1217

713-862-6622

Fax: 713-861-9953.

737

AORN J O U R N A L

MARCH 1990, VOL. 51, NO 3

Employees May Threaten Computer Security Many people are concerned that teenage geniuses who tap into industrial and government computer systems from personal computers may breach their computer security. Hospital administrators should be more concerned about their employees, according to an article in the Nov 3, 1989, issue of Modern Healthcare. Systems that do not allow telephone access are safe from “hackers,” and with telephone access, systems can be protected with dial-back devices, passwords, and special software that blocks unauthorized calls. Hospital employees, however, always have access to the files, and often they are merely curious, not out to sabotage the sytem. Dennis

Casey, a former medical records administrator who was quoted in the article, gives an example of an in-hospital patient and his neighbor, who works at the hospital. The neighbor checks the computer to see why the patient is there. It is human nature, Casey says. Casey recommends in-service training for new employees to make them sensitive to the implications of medical information. He says in-service instructors should ask the employees how they would feel if their neighbors found out that they (or one of their girlfriends) had an abortion in the past.