Coding truths and myths

Follow the author as she navigates periodontal coding for a patient

Follow the author as she navigates periodontal coding for a patient

BY Patti DiGangi, RDH, BS

As a futurist, I see the day coming very soon for a profession of dental coders, or of a dental specialty within the medical coding world. That day has not yet arrived, which means dental hygienists, who often prefer to take a hands-off approach, need to step up and truly learn about coding. What we think we know about coding often affects the care we offer. This carries risk - risk to patients' health, risk for the practice, risk to your license, and the risk of being unprepared in a rapidly changing world.

Dental hygiene is the backbone of many practices, with much of the diagnosis and treatment planning happening during hygiene appointments. Insurance carriers and the Affordable Care Act (ACA) are driving value-based care. Part of the ACA is aimed at improving the quality, efficiency, and overall value of health care. Reimbursements will be tied to outcomes in the future. Many dental hygienists balk at offering a wider variety of preventive services that insurance won't cover. The truth of the matter is that unless you're holding a policy in your hand, understand how to read it, and know what care has been rendered to date, there is no way to know what is or isn't covered. (No matter what your computer might say, it is only a guesstimate.)

Kelly's dental-medical necessity

Let's look at Kelly's case history (see sidebar) to illustrate. Kelly is exhibiting signs of a caries infection and oral cancer risk, yet for this exercise we will home in on her periodontal condition. How should her care be coded? The answer depends on her dental-medical necessity. The basis of all coding, including periodontal care, should be dental-medical necessity, a term and thought process that's not well known in dentistry. But as a dental hygienist, you do know and probably document it daily. There are many legal and other definitions; yet it simply requires documenting the reason a procedure is needed.


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Kelly is a patient of record and scheduled for a periodic exam. She presents with some obvious signs of periodontal and health changes. In order to diagnose Kelly's periodontal status, data collection includes full periodontal probing. The eternal question is if the D0180 code is a code for periodontal probing. The answer is no. This code was established to indicate the extra time and effort needed for evaluating a patient's periodontal condition to establish the most accurate diagnosis, and includes using a risk assessment.

(By the way, for the D0180 code and any code listed in this article, please refer to "Current Dental Terminology 2015" and "Systematized Nomenclature of Dentistry" from the American Dental Association.)

You might have something like this listed in your notes:

• Spontaneous tissue hemorrhage, blunted papillae, bad taste, and odor

• Severe inflammation with marked redness, edema, enlargement, spontaneous bleeding, and ulceration

These satisfy Kelly's dental-medical necessity for the D0180, comprehensive periodontal evaluation-new or established. As mentioned, dental hygienists often know the dental-medical necessity, but it isn't recorded into the insurance documentation.

The periodontal condition for Kelly shows:

• Generalized 4 mm pocketing with gingival tissues appearing 1+ mm enlarged and hemorrhagic

• Nos. 14 and 15 area 5 mm with exudate present

• Using Loe & Silness Gingival Index: Moderate inflammation generalized with severe inflammation on Nos. 14 and 15

• No recession, fremitus, or furcation is noted

Kelly's Case History

Kelly is a 20-year-old college student who is away from home for the first time. Her medical history includes taking Yaz, multivitamins, and she may be pregnant. She noticed some white spots on her teeth and bleeding gums, and mentioned she started drinking energy drinks to help get schoolwork done. She did admit to adding vodka to the energy drink on the weekend, as well as a few cigarettes and some "vaping." Kelly has been your patient since childhood. She has no previous history of periodontal disease or cavities documented. Kelly's first words to you are, "No, I am not flossing. Don't yell at me."

Radiographs and pregnancy - Kelly stated she might be pregnant, which has traditionally meant no X-rays. But that is based on old information. More recent research says that leaving dental disease, particularly periodontal disease, untreated during pregnancy can lead to problems for both the mother and fetus. The American Dental Association (ADA) recommends that every precaution be taken to minimize radiation exposure to the pregnant patient. The estimated fetal doses from typical radiographic examinations support the conclusion that fetal risks are minimal. Radiologic examinations that may provide significant diagnostic information should not be withheld from pregnant women.

This position was further supported by the American College of Obstetricians and Gynecologists in their 2013 opinion paper, "Oral Health Through Pregnancy and Through the Lifespan." Based on Kelly's medical condition, periodontal charting, and possible pregnancy, the minimum radiographic images required are D0277 vertical bitewing images, and D0220 single periapical image Nos. 14 and 15. Similar to changing the procedure expected for the exam/evaluation, many practices might not consider taking radiographs at eight months. However, Kelly's presenting condition warranted a change in the diagnostic protocols.

Bone height and diagnosis - Bone height must be evaluated to determine if there is loss. A normal measurement from the alveolar crest to the CEJ is 1.5 mm to 2mm. Comparing the current radiographic images to a set of bitewing radiographs taken on Kelly eight months earlier, it is clearly noticeable that there is 2 mm of bone loss between Nos. 14 and 15. This is critical in making her diagnosis. It is not based on pocket depth only.

Kelly's periodontal diagnosis is:

• Plaque-induced gingival disease modified by systemic factors - pregnancy

• Nos. 14 and 15 chronic periodontitis with 2 mm bone loss

Codes and coverage not the same thing

Now, view Kelly's preliminary treatment plan in the sidebar. How many of you already think insurance won't cover all of it? This is probably not accurate because a clear dental-medical necessity has been established, as well as a clear diagnosis. Often these steps are skipped or not documented.

We aren't talking about coverage here; we're talking about codes. The existence of a code does not mean a patient has coverage under a policy. Yet without a code, no coverage can be offered. This is where the confusion lies. Codes and coverage are related but are not the same. It is the obligation of the practice to use the code that most accurately describes the procedure.

The coding truths and myths for Kelly's treatment plan include the following considerations:

Anesthetic: Though a code exists for anesthetic and Kelly certainly wants to have it, there is no code listed. At the beginning of the periodontics section of the current CDT book, it states, "Local anesthesia is usually considered to be a part of periodontal procedures." This was reconsidered by the Code Maintenance Committee for CDT 2015. The committee believes the rationale submitted to support this action did not add clarity or improve understanding of the current code, and declined to make the change. (DentalCodeology CDT 2015 Shifts)

Laser curettage: Codes are procedure-based rather than product- or instrument-based, e.g., nonsurgical periodontal therapy. For example, there is not a different code for using an ultrasonic scaler vs. hand instruments. The same is true of laser therapy. In earlier versions of CDT, there was a code for curettage. Based on the AAP Statement on Gingival Curettage, the procedure code was removed. (AAP 2002) There is no universal agreement on this position. For CDT 2015, the committee continued to vote no for a variety of laser-assisted periodontal therapy submissions. The rationale was that since lasers are used in conjunction with other procedures, they could not identify how the submissions were different from procedures reported under current codes.

D4341/2 and D1110 on the same day: There are no restrictions on quadrant/isolated nonsurgical care and prophylaxis that would preclude use with any other procedures. There is nothing in CDT coding that states D4341/2 and D1110 cannot be billed on the same day. Again, coding and coverage are not the same. It is the obligation of the practice to use the code that most accurately describes the procedure.

Kelly's preliminary treatment plan

• D0180 comprehensive periodontal evaluation-new or established

• D0277 vertical bitewing images

• D0220 single periapical image No. 14 and15

• D4342 periodontal scaling and root planing-one to three teeth per quadrant Nos. 14 and 15

• D4921 gingival irrigation, per quadrant

• D1110 prophylaxis-adult

• D1206 topical application of fluoride varnish

• D1310 nutritional counseling for control of dental disease

• D1320 tobacco counseling for the control and prevention of oral disease

• D1330 oral hygiene instructions

Gingival irrigation: Kelly was diagnosed with No. 14 and 15 chronic periodontitis with 2 mm bone loss. Gingival irrigation is a service many dental hygienists provide when treating periodontal disease. The Codes Maintenance Committee discussed adding a code for CDT 2014 even though it has not been supported in the past. Some code committee members questioned the clinical efficacy of a onetime gingival irrigation. In this case, practitioners made a difference. Insurance carrier records show that gingival irrigation was submitted as D4999 unspecified periodontal procedure over 500,000 times in 2012. Therefore, a new code - D4921, gingival irrigation per quadrant - was added to CDT 2014 and is now available for practices using this therapy. In our case study, this should be documented and submitted for Kelly.

D1330 oral hygiene instructions: We know Kelly needs to clean her interdental spaces to prevent, manage, and heal her periodontal disease. Kelly stated at the beginning of her appointment - and her behavior has consistently maintained - that she does not want to and will not floss.

We could continue to harangue, beg, and reprimand her behavior; however, it may be time for new ideas. With ever-changing and improved technology, we can offer new options. Curaprox, USA, a Swiss-owned company, is now entering the U.S. Curaprox products have been created and developed in Switzerland and offer a new generation of interdental brushes that respect the papilla (which floss cannot) and are equally suited to young and elderly patients, as well as skilled and less skilled individuals.

However, handing Kelly a "one-size-fits-all" interdental brush isn't a great solution. Different interdental spaces need different brushes. Curaprox includes an innovative probe that helps measure the space to help in selecting the correct size for each interdental space. Does this take time? Absolutely. Can an office be compensated for this time and expertise?

(Join me at RDH Under One Roof this July for my course, "Floss Off: Individually Trained Oral Prophylaxis (iTOP)."

ADHA Standards of Clinical Practice list the professional roles of dental hygienists as clinician, advocate, administrator/manager, researcher, and educator. When questioned, a majority of dental hygienists say the most important part of the care they offer is patient education. Yet oral hygiene instructions are often not documented or coded. Why don't dental hygienists code D1330? Because we think there isn't benefit coverage. The American Academy of Periodontology says it this way: "The treatment plan should be developed according to professional standards, not according to the provisions of the contract." Clinicians don't know what a policy covers. Whether a practice chooses to charge a fee is a practice management choice.

Coding Kelly's follow-up care involve the following considerations:

D4910: Kelly's periodontal diagnosis was plaque-induced gingival disease modified by systemic factors - pregnancy, and Nos. 14 and 15 chronic adult periodontitis with 2 mm bone loss. All the words of the long definition for D4910 are important for a successful submission: "...instituted following periodontal therapy and continues at varying intervals, determined by clinical evaluation of the dentist for the life of the dentition or any implant replacement..." So yes, Kelly qualifies under D4910. (Further discussion that Kelly's state of oral health is not stable on recall can be found in the book "More than Pocket Change" at

• D1110: What if Kelly comes back for her three-month appointment and is not pregnant and her periodontal condition is stabilized. Can she go back to D1110? ADA has added a Q&A and says this is a matter of clinical judgment. It is appropriately reported as D4910, but if the treating dentist determines that Kelly can be treated with routine prophylaxis, D1110 may be appropriate. D1110 can be used for Kelly, but later she cannot go back to D4910 without a new diagnosis and treatment of an active periodontal infection with bone loss.

Alternating D4910 and D1110: Follow-up care for a patient like Kelly who has received active periodontal therapy can receive the D4910 code. A carrier can only say what is covered under a policy. This does not mean this is the correct coding. Back in 2006, a dentist from the ADA dental benefits office said, "D1110 and D4910 are not interchangeable and should not be alternated. The dentist must make the diagnosis, but then the proper code for the procedure provided needs to be used. It does appear that you could choose one code or the other, based on the diagnosis, but it would never be appropriate to alternate them."

Mark Rubin, JD, legal counsel for ADA, further responded in 2006, "Knowingly alternating the D1110 and D4910 to maximize insurance benefits would constitute fraud. We must code for the procedure being performed. By doing otherwise, the Attorney General could make a convincing case for prosecution." Nothing has changed since these 2006 answers in regard to alternating D1110 with D4910; they cannot be alternated.

One option comes from Dr. Charles Blair, one of dentistry's leading authorities on practice profitability, fee analysis, insurance coding strategies, and overhead control, and author of "Coding with Confidence 2015" (a book I highly recommend). He offers a strategy for managing this sticky issue. A narrative can be added to a claim form that states, "If periodontal maintenance (D4910) is not available for reimbursement, please provide the alternative benefit of (D1110) prophylaxis." This is different than changing the code. As noted above, purposely changing a code can be considered fraud.

Reducing your risk

Electronic health records (EHRs) will require the use of uniform health information standards, including a common language. The current standard language for dentistry is Current Dental Terminology (CDT). This system is generally thought to be used only for efficient processing of dental claims. Though CDT is for dental claims processing, it is not only for that purpose. Another purpose for CDT is as a standard language to populate EHRs.

In addition, diagnostic vocabulary designed for EHR is needed. Though not completely decided as yet, the ADA is in support of SNODENT - the Systematized Nomenclature for Dentistry. Others would prefer what is used commonly in medical - the ICD-9 or the upcoming ICD-10 coding systems for diagnosis. Those decisions will come sooner rather than later; yet it is not time to wait. Use of structured data can start now by making optimal use of CDT codes whether there is coverage or fee involved.

As dental hygienists, we know there are gaps in the codes. Not everything is a prophylaxis or perio maintenance. SRP language is outdated and harkens back to a 1950s periodontal philosophy. This gap and the quickly approaching EHRs are the reasons for the DentalCodeology book series. Kelly's case is one of the five cases introduced in the book, "More than Pocket Change." Kelly's story continues in "Jump Start Diagnostic Coding." We will see more of Kelly and the other cases as the series moves forward.

Change is not coming; change is here. DentalCodeology are easy-to-read, bite-size books for busy people to help them prepare for the transition to profitably. RDH

Patti DiGangi, RDH, BS, continues to take a future-oriented leadership role in a variety of professional organizations. She is a certified Health Information Technology trainer, shaping the changes in our interoperable electronic health record world. Patti is an ADA Evidence Based Champion and holds publishing and speaking licenses with the American Dental Association for Current Dental Terminology and SNODENT Coding. She is the author of the DentalCodeology series of bite-size books for busy people. Patti received the 2014 and 2015 Dentistry Today CE Leaders recognition. Patti was awarded the 2014 Sunstar Award of Distinction and the 2013 Sonicare Mentor of Distinction award. Contact her at or

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