Dental Implants

What every hygienist should know about the latest in tooth replacements.

Th 67216

What every hygienist should know about the latest in tooth replacements.

by Cathy Hester Seckman, RDH

Click here to enlarge image

How much do you really know about implants? When patients ask, do you fumble through an explanation and suggest they talk to the dentist? That's what I used to do. In nearly 20 years of dentistry — mostly in small, solo practices — I had seen perhaps 30 implant patients. Most had either single-tooth replacements or a blade anchoring a posterior bridge. I wasn't sure what they went through to get those implants. I didn't have a clear idea of how the implants worked, or why. I couldn't say what the patients should expect from them. When I saw an implant, I was likely to say, "Wow, cool! Yours is the first one like this I've seen."

Click here to enlarge image

We all know the basics of implantology, if we know nothing else. A titanium device is inserted subgingivally with one or more posts extending through the gum. A crown, bridge, or full denture is attached to the posts. There are two basic types of implants: endosseous (blades, screws or cylinders placed within the bone), and subperiosteal (framework placed on top of the bone).

Click here to enlarge image

A third type, less popular today, is the mucosal insert, which is placed within soft tissue instead of bone. These were a big surprise to me. A patient took out her upper denture one day and I was shocked to see four mushroom-shaped metal plugs embedded inside it. I had already looked at her panoramic radiograph and knew she had six natural teeth and two blade implants on the lower, and was edentulous on top. How in the world could she wear a denture with metal plugs in it?
Mucosal inserts (top photo) — titanium posts embedded in a denture — are used for extra retention. Each post fits into a soft-tissue receptor site in much the same way earrings fit into pierced ears. Relatively normal function, an immovable denture, and a natural-looking smile give patients a confidence about their mouth they may never have had (middle photo). Abutment posts (bottom photo) provide a connection between the implant in the bone and the tooth it supports. The abutments may support individual teeth, bridgework, a full denture, or a connecting bar that supports a denture.

"It's like having pierced ears," the patient said with a smile, seeing my confusion. "That's how it was explained to me," she said, "those little plugs fit into holes in my gum — permanent holes — like in my ears." She flicked her gold hoop earrings, then opened wide to display her maxillary ridge. Sure enough, there were four healthy-looking receptor sites — one each at the first molar and cuspid locations. It was easy to see that the mushroom shapes of the titanium plugs would fit snugly into those sites and provide extra retention.

"Wow, cool!" I said. "Yours is the first one like this I've seen."

Still just a cool thing to see?
I don't think my situation is unusual. Though implants gain in popularity every day, they still aren't common, especially in rural areas. A hygienist can see patients for weeks — even months — and never run across an implant, though the concept is older than most of us.

It was 1952 when professor Per-Ingvar Branemark of Lund, Sweden, accidentally discovered that titanium would bond to living bone tissue. He named the phenomenon "osseointegration," and research began. By 1965, the first patient had received dental implants.

In the years since, implant systems have come and gone. Subperiosteals, blades and mucosal inserts have begun to go out of fashion because of bone resorption problems, and same-day implants have begun to come into fashion because of patient demand. Today, implants have at least a 92 percent chance of success and can be expected to last 15 to 20 years.

In a recent study done at Dalarna University College in Sweden, 97 percent of implant patients reported overall satisfaction. Ninety-nine percent rated chewing ability as good or very good. Improved lifestyle was reported by 75 percent, and increased self-confidence by 82 percent.

The relative scarcity of implants is about to change for all of us, because they're getting more common every day. Oral surgeons and prosthodontists at Thomas Jefferson University Hospital in Philadelphia estimate they place 150 implants every year, triple the number they placed just two or three years ago.

Things changed for me when I took a job with Dr. Keith Fammartino, who does implant surgery as confidently as he does a composite restoration. Though he has a general practice in Beaver Falls, Pa., he has also been placing implants for many years.

Nowadays, I might see 20 implants in a week, and they're all different. A pair of cylinders might replace congenitally missing lateral incisors. A screw-type implant in the bicuspid area might match a solo molar to form a posterior bridge. A set of tapered cylinders might support a fixed denture on a fully edentulous maxilla. A subperiosteal framework might support a bar to which a removable lower denture snaps.

Keeping up with the options
That versatility is what makes implants so useful, according to Dr. Bernard I. Krupp of Mercy Medical Center in Baltimore. 'There are so many options available today," he said, 'so many sizes and varieties and applications to choose from. Why would you do something less when there are so many implant options? We place implants routinely — it has become an everyday occurrence."

I've talked to several specialists to discover what a hygienist should know about the burgeoning field of implantology. Dr. Krupp, an oral and maxillofacial surgeon who specializes in cosmetic and reconstructive surgery, outlines the criteria necessary for a successful implant. "First of all, we look at bone quality. We determine the quality of bone from X-ray, and from examining mounted occluded models with a facebow transfer. There has to be adequate bone height and width. Secondly, we look at hygiene — is it good? Thirdly, we look at occlusion, making sure, for instance, that an implant would be in proper alignment with enough occlusal distance."

Dr. Krupp has the ability to grow three-dimensional bone where needed, in the maxillary sinus areas or in severely atrophic mandibular ridges. "One of the adjuncts with crafting bone is platelet-rich plasma," he said. The plasma, a rich form of blood product, is used as a surgical dressing to minimize bleeding and enhance wound healing. It increases bone graft consolidation and maturation by nearly 50 percent.

A new bone technique, called osseodistraction, involves growing bone and soft tissue vertically using an osteotomy approach where bone is separated from a bone plate to lengthen it. "It gives us a terrific ability to put bone where we need it easily. We have all these tools today that we didn't have even five years ago. What they do is allow any patient to become an implant candidate. It's relatively easy, and it gives them options for predictable and aesthetic results," affirmed Dr. Krupp.

Dr. Robert J. Diecidue is the director of the oral and maxillofacial surgery division at Thomas Jefferson University Hospital. His specialties include implants, reconstruction of the maxillofacial region, and correction of dentofacial deformities and TMJ. In his practice, he mainly uses endosseous screw-type implants. He said, "Typically I'll use six or eight implants and build a roundhouse of bridgework that is fixed, but removable. It's screwed in, and every six to eight months we remove it for cleaning and inspection."

His patients have a success rate of 97 to 98 percent on the mandible, and 92 to 93 percent on the maxilla. Dr. Diecidue, who says he practices "very conservative, very conventional oral surgery," spends five or six months working with each implant patient in more than a dozen appointments.

"The first step is a consultation with the oral surgeon, then another with the restorative dentist," he said. "Next comes the day of the procedure, when we place the implants in the bone then suture gum tissue over them to allow for osseointegration. We use intravenous sedation or general anesthetic, depending on the patient's circumstances and whether bone grafting is necessary.

"We follow the patient weekly for four weeks, then see them at two and a half months to take a panoramic radiograph and determine whether to uncover the implants. A week later we uncover and place a healing abutment, then let that sit for two weeks.

"At that point the patient is sent to the restorative dentist for impressions. They put in the post, and send the post with the impression to the lab. There are two or three try-ins, then the prosthesis is delivered and seated. We follow the patient at monthly intervals for six months, then yearly thereafter."

And then there are sleepers
To guard against possible failure, Diecidue uses what he calls "sleepers." In a case where multiple implants are needed, he tries to put in a few extra ones. "Especially if I'm putting in eight, I might as well put in a ninth and tenth, if there's room. We don't charge for the extra ones, and in case one implant fails, we have others still submerged for a rainy day."

During the six-month transitional period, the patient has very limited chewing function, and might need a soft or liquid diet. Temporary bridges or dentures can help patients over the gap.

A more radical approach to implants is same-day placement, where the patient goes home after surgery with useable teeth, instead of just implants submerged in gum tissue. Dr. Steven Eckert, a consultant with the division of prosthodontics in the department of dental specialties at the Mayo Clinic in Rochester, Minn., is very enthusiastic about the new technology.

"The industry is moving toward shorter and shorter healing periods because of patient demand," he said. "With same-day implants, there's a very precise location for each implant, and rigid fixation to a connecting bar above the gum tissue. Placements are chosen for force and stress distribution. The placement of the drill provides the exact positioning necessary to fix a pre-fabricated connecting bar to the implants. The bar provides rigidity and immobility that allows implants to heal to bone. The patient goes home that day with teeth in place."

Patients start out with a soft diet, of course, and gradually move to harder foods. The same-day technique, Dr. Eckert said, was developed in Sweden and has a success rate equal to that of conventional implants.

Eckert calls it a technological advance, rather than a scientific one. "The only reason long healing times were necessary was for the bone to heal to the implant. It only does that if the implant is immobile. This new technique places the implant in a very exact position." Micromovements caused by occlusal function, therefore, are minimized and have little impact on healing.

Three to six preparatory appointments are necessary for same-day placement. The oral surgeon and prosthodontist look at the size and shape of the patient's jaw to determine correct positioning for each implant. A connecting bar is prefabricated, so the implants can be fitted to it during surgery.

The shortened healing period, according to Dr. Eckert, is a valuable aspect of implant treatment, because patients don't have to go through a series of temporary prostheses.

Patients who choose implant surgery fall into three groups, said Dr. Diecidue. "We have younger people in their 20s and 30s who have usually lost teeth due to trauma; middle-aged patients who have lost some teeth and can't use a partial; and edentulous patients in their 70s and 80s who just want to be able to chew again before they die."

Cost is certainly a factor in a patient's decision. "Of course, it's not for everyone," Dr. Diecidue admits. Implants aren't reimbursed by insurance, so it's totally fee-for-service. If residents are involved in the surgery, we can offer certain discounts."

Dr. Krupp usually sees no problem with his patients' finances. "They're absolutely willing to spend the money. All they have to do is weigh the positive benefits. The teeth are esthetic and retentive, and depending on the case, can be inexpensive. Just compare the cost of a couple of implants to the cost of not being able to chew. Compare implants to a car that depreciates. It's easy to see when you understand the benefits."


The Hygiene Factor
A hygienist can be a key player in a patient's decision to get implants, the specialists agree. Dr. Krupp says, "A hygienist should tell a patient who asks about implants that they are the absolute best replacement for any missing teeth today. They're cost-effective, inexpensive to restore, take less time to prepare than natural teeth, and the esthetics are excellent."

Dr. Diecidue outlines three factors a hygienist can assess when a patient is considering implants:

Look for adequate bone structure. A panoramic gives a good indication. Look at the height of bone between the alveolar crest and the mandibular nerve. On the maxilla, look at the space between the alveolar crest and the floor of the maxillary sinus. (Dr. Eckert says an implant can be placed in as little as 8 mm of bone.)

Consider the patient's lifestyle and health. With a smoker, the success rate drops significantly. An immunocompromised patient also has a decreased success rate. In a patient with a history of jaw radiation, the bone is not as vital and there might not be adequate blood supply. Hyperbaric oxygen treatment might be necessary first.

What's the overall health of the mouth? If they can't maintain their teeth, they can't maintain an implant, either. That's where the dental team has to be keenly aware. If the patient lost his teeth due to negligence, he may also lose implants down the road.

Cathy Seckman, RDH, is a frequent contributor who is based in Calcutta, Ohio.

(Photos courtesy of Keith Fammartino, DMD)

More in Radiology