Links:

JIRA: https://projects.jira.snomed.org/browse/IHTSDO-238

Document review: JIRA IHTSDO-238 (artf227303) Representing Tooth and Teeth in FSNs Documentation Review

Title

artf227303-Representing "tooth" and "teeth" in FSNs to appropriately distinguish when the concept necessarily involves multiples.

Version Information

Document review

Statement of problem as requested or initially identified

Submitter suggested to change the FSN of Supernumerary permanent teeth (disorder) to Supernumerary permanent tooth (disorder).
The concept Supernumerary permanent teeth (disorder) was not renamed to include the singular tooth in the FSN because it is not entirely clear when "teeth" in FSNs is intended to necessarily represent multiples.
This led to a more comprehensive review where either tooth or teeth was used in the FSN and subsequently whether the singular tooth concept was subsumed by a concept using the plural teeth and whether this was appropriately hierarchically.
In a review of almost 700 concepts having a tooth/teeth combination in its stated or inferred view, it became evident that there were concepts referring to an incorrect body structure and whether the appropriate body structures were available for dental terminology.
The CRG looked at this initially from a more global view and whether we could define tooth as being singular and teeth as meaning plural IN ALL CASES. It was determined by the group that we could not make it an absolute, but that this should be the guiding principle.
There are about 180 active concepts with teeth in their FSNs. These could be reviewed as to whether some of these FSNs should be changed to "tooth" or whether these concepts truly pertain to "multiple teeth". Although "teeth" by definition means more than one, it is not clear that all FSNs that refer to "teeth" necessarily were intended to mean more that one tooth (e.g. Erosion of teeth (disorder) has description "Tooth erosion").
One option would be to assume that "tooth" means "tooth or teeth". In that case, "single tooth" should be used in FSNs to represent "one tooth" (e.g. SNOMED CT has Supernumerary tooth (disorder) and Single supernumerary tooth (disorder)). Concepts with "teeth" in their FSNs could then be reviewed to determine which concepts necessarily mean more than one tooth (e.g. Crowding of teeth (disorder)) and where the use of "teeth" might create ambiguity (e.g. Supernumerary permanent teeth (disorder) and Erosion of teeth (disorder)). If it is decided that "teeth" in an FSN necessarily implies multiple teeth, then concepts with "teeth" in their FSNs should not have "tooth" subtypes.

Relevance to International edition

This is foundational for dentistry irrespective of country.

Related changes impacted by this content development request

Beyond the individual concepts that may need changing, it is anticipated that there will be a need to add multiple concepts to provide for tooth to tooth and teeth to teeth relationships. Prior to finalizing those, it will be necessary to review body structures and identify necessary changes or additions to allow for proper classification and hierarchical relationships.

Agreed scope statement

The scope is limited to refining (and adding where necessary) all concepts having relationships that may have a singular "tooth" and a plural "teeth" in its concept model. It is understood that to accurately complete this project, it will require possible additions or definition changes to body structures that intersect with the teeth.

Identify additional changes
See scope statement

Solution proposed

1. Review and refine body structures that intersect with the dental structure of teeth.

2. Identify concepts that have a singular finding site and a plural that it is either a stated or inherited attribute.

3. Revise those concepts, as appropriate, to use singular and singular or plural and plural. This may require additional new content. The CRG determined that the guiding principle should be that a singular finding site should have only singular attributes and plurals should have only plural attributes, but recognizes there may be a few exceptions .

4. Addition of concepts to provide the proper singular and plural relationships.

Stakeholder input
The problem was identified in a CRG content request review and the entire CRG has been very committed to a solution, including reaching out to current users and vendors, as well as specialty experts in all dental fields.

Impact assessment
We anticipate correcting the identified errors as noted above. Additionally, we anticipate that, as we develop further concept modeling and searches that other issues may (will) arise, but we are unable to specifically point to any.

Risk assessment
The CRG has recognized over time that there are several areas involving dental concepts that are not "correct" or as precise in their description as they should be. There are also some synonyms that may be incorrect and potentially inheritance issues that could impact other groups of dental concepts. At this time, we do not foresee impact on other aspects of SNOMED concepts.

Approval process