N/A is not permission

A code table can look calm right before it creates the wrong answer.

UnitedHealthcare’s 2026 Medicare dental claim review guideline lists intraoral tomosynthesis codes next to ordinary diagnostic imaging codes. For D0372, D0373, D0374, D0387, D0388, and D0389, the documentation column says N/A. The related dental policy column also says N/A.

A weak automation reads that as permission. No documents required. No policy attached. Clear enough to process.

If you run a business: A blank field in one document only tells you what that document does not require. It does not tell you what other rules still apply. Before you let software or a new hire treat an absence as approval, make sure they know which question the source was answering and which questions still have to be checked somewhere else.

That is not what the source says.

The guideline is a standard claim-review document, not the member’s benefit schedule, vendor routing contract, or final patient-balance rule. UnitedHealthcare may still request documentation periodically. Member-specific Medicare Advantage, SNP, and Medicare-Medicaid product terms supersede the standard criteria.

So N/A is not a green light. It is an absence state inside one source surface.

That distinction matters because dental benefits work is full of near-identical rows that answer different questions. One document may say whether a code is covered by a plan package. Another may say whether an attachment is required before review. A vendor manual may define routing. A benefit schedule may decide frequency. An explanation of benefits may decide whether the provider can bill the member. A plan-specific document may override the standard guideline.

Those facts cannot be collapsed into one covered/not-covered flag. They sit in different documents and carry different consequences.

For Hadto, this is an ontology problem before it is an automation problem. The model has to preserve the layer that produced the fact. A review guideline can say N/A for documentation. A benefit schedule can still set a frequency limit. A member plan can still supersede the standard rule. A vendor manual can still define routing and proof duties. An explanation of benefits can still decide the balance.

If those layers are flattened, the system becomes confidently wrong in the exact place an owner needs it to be cautious. It may tell a front desk team that no evidence is needed when the real answer is narrower: this standard review table does not name an attachment requirement, but plan terms and periodic review can still matter.

Owner-ready software should carry that uncertainty without turning it into mystery. The workflow should show the operator which question is answered, which source answered it, and what remains unresolved.

That is the practical rule from this source: model absence as a typed fact.

N/A documentation is not the same as covered, not covered, no review, or member may be billed. It is a review-burden value inside a Medicare-only claim-review guideline.

Domain experts can become owners when the business gives them infrastructure that preserves judgment instead of hiding it. In a clinic, that means the person working a claim should not need private memory to know whether a dental code row came from a benefit guide, a claim-review guideline, a vendor manual, or a plan schedule.

The system should make the source layer visible. Then the operator can act without guessing what a blank-looking table cell meant.

Source note: reviewed UnitedHealthcare’s National Standardized Dental Claim Review Guidelines for Medicare Only, effective January 1, 2026, plus Hadto’s internal 2026-05-10 ontology research notes.