D1110 and D4910

April 1, 2011
What's the difference, and why is it hard to explain?

What's the difference, and why is it hard to explain?

by Dianne Glasscoe Watterson, RDH, BS, MBA, and Bill Landers

You have completed a series of definitive periodontal scaling visits with your patient. The next step is periodontal maintenance, which will require the patient to return every three months. After two visits, the patient learns that he is being charged more for maintenance visits than his spouse's preventive visits and wants to know why.

The necessity for maintenance

Many patients resist regular periodontal maintenance visits after a definitive periodontal scaling. One reason is the higher fee charged for a D4910 periodontal maintenance than the fee for D1110 prophylaxis. The other reason is that most third-party payers do not cover care at three-month intervals.

There is clear evidence for the necessity of a season of maintenance. Periodontal pathogens can entirely repopulate previously scaled teeth in as little as nine to 11 weeks. The majority of periodontal patients are not able to debride the depths of periodontal pockets with self-care measures alone. In fact, a position paper published in September 2003 by the American Academy of Periodontics states that "tooth loss in periodontal patients is inversely proportional to the frequency of professional care." Following a 10-year study, researchers found that patients who had undergone regular periodontal maintenance had significantly reduced probing depths and lost fewer teeth than patients who did not have periodontal maintenance procedures. These are logical arguments for the necessity of maintenance.

However, many hygienists perform exactly the same procedures for a prophylaxis as they do for periodontal maintenance. It's only natural for patients to balk at paying higher fees when there doesn't seem to be any difference between a periodontal maintenance appointment and a prophylaxis appointment.

"What we have here is a failure to communicate." – Cool Hand Luke, 1967

Some hygienists themselves don't understand that there are indeed important differences between a periodontal maintenance procedure and a regular prophylaxis. Others understand the difference but have trouble explaining it to their patients.

What makes the codes different?

The D1110 prophylaxis is only for people who do not exhibit any of the signs and symptoms of periodontal disease, including bone loss, bleeding, mobility, exudate, and recession. D1110 is, thus, a preventive procedure for patients who don't yet have periodontal disease and should only be used with patients who are periodontally healthy. As the CDT definition says, D1110 is for "the removal of plaque, calculus, and stains from the tooth structures in the permanent and transitional dentition. It is intended to control local irritational factors."

The D4910 code, on the other hand, is a post-therapeutic procedure used to maintain the results of periodontal therapy, not to prevent disease in healthy patients. The CDT definition for D4910 states that it can only be used "following periodontal therapy and continues at varying intervals ... includes removal of the bacterial plaque and calculus from supragingival and subgingival regions, site-specific scaling and root planing where indicated, and polishing the teeth."

The D4910 code is to be used following definitive perio therapy for an indefinite time, determined by the patient's progress over time to achieve stability and the absence of the signs and symptoms of disease. Some patients have great success after a year or two of definitive maintenance and reach a point where they have no signs or symptoms of active disease; i.e., little, if any, bleeding on probing and no continuing loss of bone or attachment. Patients in this category do not smoke and have very good to excellent oral hygiene. Other patients never get to the point of having no signs and symptoms of disease. Maintenance patients who have poor oral hygiene, smoke, and continue to exhibit bone loss and/or excessive bleeding have not achieved an acceptable level of stability and good health. Such patients should be seen by a periodontist and may need D4910 maintenance indefinitely after definitive treatment.

What are the specific differences between a periodontal maintenance procedure vs. a regular prophylaxis? Periodontal maintenance procedures include a predominance of power scaling with thin inserts to access and debride the depths of periodontal pockets. Your patient may need anesthesia of some type. The goal is thorough debridement of pathogens that have repopulated in the sulcus. Periodontal pathogens reside on and in calculus, on root surface biofilm with no calculus, in sulcular epithelium, and free-floating in the sulcus. Most likely, a six-point periodontal probing is necessary in order to reassess changes that have occurred in pocket depths. Irrigation post-procedure with an appropriate antimicrobial, such as povidone-iodine or chlorhexidine, might be needed. You may need to apply desensitizing agents, such as Colgate's Pro-Relief™, with a rubber cup if your patient has sensitive, exposed root surfaces. If your patient has exposed root surfaces, which is often the case with periodontal patients, any polishing should be with low-abrasion pastes.

How to explain the differences to patients

If a patient is not completely healthy and needs continued periodontal maintenance, one way to explain the difference is to say: "The reason your fee is higher is because your gums still aren't completely healthy. If they were healthy, my job would be a lot easier and the fees would be the same." Or, "It all depends on you. If you do all the things we advise you to do at home every day, there's a good chance your gums will heal. When they're healthy, you won't need anything more complex than an ordinary preventive prophy."

Some patients will need more convincing. In their mind the problem isn't their gums, it's your fee. They think the practice is taking advantage of them. It's an emotional issue. The problem isn't that they don't understand what you're trying to say. It's that they don't believe it. The patient thinks that the practice is trying to cheat him because he's being charged more for the same procedure than his spouse was charged. Trying to explain the factual differences between a D4910 and a D1110 is the wrong approach with these patients, because they're not thinking intellectually. It's an emotional response to a perception of unfairness. The patient is mad because, from his point of view, you're charging him more money for the same amount of time. Since you're the one who's charging him, you're part of the problem and your explanations are suspect.

These patients are going to need compelling evidence – something besides your (from their perspective) self-serving explanation. What's needed is an independent authority – something other than your words – that the patient can believe in. So, what kinds of authoritative, compelling evidence can you provide that the practice isn't trying to bilk the patient, other than your say-so? One way is to show the patient photographic proof. If you have intraoral photographs of both your patient and his spouse, intraoral photos will help the patient see the same differences you see. The clinical differences, such as inflamed tissue and bleeding, are obvious even to a layman. Please remember, however, that HIPAA regulations preclude a hygienist from discussing specifics of a spouse's periodontal condition with the other spouse unless given written permission. It is permissible to provide information about the transmissibility of periodontal pathogens between individuals.

Charts are another type of independent authority, but they'll need to be graphic so the differences are clear for anyone to see. A device such as the Florida Probe™,1 for instance, can transform dull probe data into striking, colorful charts. Some computerized patient management software programs and stand-alone devices and programs, such as the Dental R.A.T.® and PerioPal®,2 also produce impressive probing charts. Even giving the patient a hand mirror and showing him how his gums are bleeding and his spouse's gums are not bleeding would be a powerful emotional tool. The main point is, the independent authority has to be highly visual and vivid to counter the emotional belief that they're being cheated.

Another approach is to use an actual independent authority. Physicians do this all the time by getting lab tests, and an increasing number of dentists are starting to use lab tests as well. Four outside labs have periodontal tests: two are culturing services – Oral Microbiology Testing Service (OMTS)3 and Oral Microbiology Testing Lab (OMTL).4 The other two are DNA tests: OralDNA Labs®5 and micro-IDent®plus.6 All four tests can detect pathogens that are highly associated with periodontal diseases. There is also a third-party statistical test, PreViser™7 based on clinical findings that estimate the likelihood of periodontal disease. In addition to these outside tests, there are two microbiological tests that can be used chairside. BANA™8 is an enzymatic test for periodontal pathogens, and the other is a video microscopy test called BioScan™.9 Any of these tests would provide patients with the kind of authoritative proof they need in order to believe they have a gum condition that requires a different type of treatment than their spouse may have.

Resolving the problem

Your job as a dental hygienist is twofold. You have to determine which type of periodic care is needed, patient by patient, and you have to convince patients that they need that care and are getting their money's worth. Once you understand the differences and realize why the patient is upset, you'll become a better therapist, and there won't be nearly so many failures to communicate.

Dianne Glasscoe Watterson, RDH, BS, MBA, is a professional speaker, writer, and consultant to dental practices across the United States. She is CEO of Professional Dental Management, based in Frederick, Md. To contact Glasscoe Watterson for speaking or consulting, call (301) 874-5240 or e-mail [email protected]. Visit her Web site at www.professionaldentalmgmt.com.

Bill Landers, president of OraTec Corporation, is an expert on microbiological tests (DNA and BANA assays; phase microscopy, cultures) with published articles and a regular column in RDH magazine. He has presented hundreds of courses to schools and societies. Landers developed the antimicrobial agent TheraSol and the Via-Jet oral irrigator.


  1. http://www.floridaprobe.com/
  2. http://www.dentalrat.com/
  3. http://www.temple.edu/dentistry/perio/omts.html
  4. http://www.usc.edu/hsc/dental/OMTL/OMTL_P01.html
  5. http://www.oraldna.com/
  6. http://www.hain-diagnostics.com/
  7. http://www.previser.com/
  8. https://www.oratec.net/
  9. https://www.oratec.net/
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