From Trisha's Desk Trisha E. O’Hehir, RDH, BS, Hygienetown Editorial Director


 
Diagnostic Codes for Dentistry
– by Trisha E. O’Hehir, RDH, BS, Hygienetown Editorial Director

If you think insurance treatment codes are a nuisance now, just wait until you're required to provide diagnostic codes as well. That day is coming. The Current Dental Terminology (CDT) codes are but a small part of the entire coding picture within the medical world.
These descriptive terms and corresponding numbers were developed by the American Dental Association and are used for insurance reimbursement. Remember, these are treatment codes, not diagnostic codes. Medicine has a similar set of treatment codes based on Current Procedural Terminology (CPT) developed by the American Medical Association. Both dental and medical treatment codes are published in the Healthcare Common Procedure Coding System (HCPCS) or "hick picks."

Diagnostic codes are routinely used in medicine, but haven't been part of the dental insurance process until now. Medical and dental diagnosis are combined in one set of codes, the International Classification of Disease (ICD). More formally, they are known as the International Statistical Classification of Diseases and Related Health Problems. These codes are published by the World Health Organization and used worldwide for reimbursement now, but were originally drawn up to systematize the gathering of morbidity and mortality statistics. The most current set of codes is ICD-10, updated in 1992, with ICD-11 scheduled to be completed in 2015. In the United States ICD-9 codes are still being used, with federal regulations suggesting adoption of ICD-10 codes by October 1, 2013.

Diagnostic codes cover diseases, signs and symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. The international version includes more than 16,000 codes. The U.S. ICD-10 codes are an expanded version including 155,000 codes. This system allows every health condition to be assigned a unique code.

In ICD-9, there are 10 topic areas under Diseases of the Oral Cavity, Salivary Glands and Jaws. One of these categories is Gingival and Periodontal Diseases, with these subcategories that also have several subcategories each:
  • Acute gingivitis
  • Chronic gingivitis
  • Gingival recession
  • Aggressive and acute periodontitis
  • Chronic periodontitis
  • Periodontosis
  • Accretions on teeth
  • Other specified periodontal diseases
  • Unspecified gingival and periodontal diseases
Here's another way to get a sense of just how many dental diagnostic codes there are; within ICD-10, dental codes are found in Chapter 11, Diseases of the Digestive System, and take up 15 of that chapter's 48 pages. There are far more dental diagnostic codes than current dental treatment codes. Medical treatment codes correspond to ICD diagnostic codes.

With so many more conditions recognized in the diagnostic codes, there is a need for more specific treatment codes. For example, chronic gingivitis should have a corresponding treatment code. However there is no dental treatment code specific for chronic gingivitis, so many patients are treated as either healthy with a "prophylaxis" or with treatment codes specific to moderate to severe periodontitis. It's an example of how so many treatments fall through cracks in the dental coding system.

Missing from the ICD codes are mention of healthy states, except "well baby visits." Dental hygiene patients are treated preventively to avoid caries and periodontal disease, so adding diagnostic codes to the dental section would be helpful: caries-free and periodontal disease-free. To be ready when insurance companies require diagnostic codes, start today by writing down the periodontal diagnosis for each patient. Many of those "prophy" patients will actually be diagnosed with disease: gingivitis or periodontitis; early, moderate or severe; localized or generalized; acute or chronic; supragingival deposits and/or subgingival deposits; calcified or soft deposits; stain, etc., making the correct diagnosis essential for determining treatment.

Inside This Section
114 Perio Reports
118 Profile in Oral Health: Caries Detection
122 Message Board: Beautiful Tissue Response – Full Mouth Advanced Case
122 Book Review: Bad Science by Dr. Ben Goldacre
Look for additional content in the Hygienetown Magazine digital edition.
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