Methods: Master code-sets including 606 and 561 terms were compiled from ICD10CM and ICD9CM by including terms that were relevant to dentistry. Similarly, 1322 terms unique to the EZCodes nomenclature were used as comparable master code-set. A cross mapping was achieved between ICD9/ICD10 dental relevant terms to EZCodes. Each term was explicitly matched to the nearest equivalent term and coded as complete, partial or no matches. The inter relationship between these code-sets, depending on the narrower or broader relationship, were then categorized into one-to-one, one-to many and/or many to one matches.
Results: Overall, 89% of the ICD10 terms matched to EZCodes, of these, 58% completely matched while 31% partially matched. Also, 79% of ICD9 terms matched with 48% complete matches and 31% of partial matches. About 292 ICD10 terms had an one to one match and 202 ICD10 terms had one to many matches. Similarly, 265 ICD9 terms had one to one match and 185 ICD9 terms had one to many/many to one matches.
Conclusion: Our results confirm that EZCodes have more granularities in expressing the dental terminology as compared to ICD9 and ICD10 codes. The reference framework for cross mapping developed during this study will form a basis for linking ICD9/ ICD10 (billing terminologies) to EZCodes (interface terminologies) in the electronic health record. This effort of unifying the terminologies will not only play an important role in continuity of care but will also help in determining the commonalities of developing a standardized dental diagnostic terminology.