D4910 vs D1110: periodontal maintenance or prophylaxis?

D1110 is the CDT code for an adult prophylaxis: a preventive cleaning for a patient whose gums and bone are healthy, or who has only localized gingivitis. D4910 is periodontal maintenance: the ongoing cleaning for a patient who has already been treated for periodontitis, usually with scaling and root planing, at an interval the dentist sets. History decides the code, however healthy the gums look on the day: a patient who has completed active periodontal therapy is a D4910 patient unless the dentist documents otherwise, and a patient who has not, with healthy gums or only localized gingivitis, is a D1110 patient. The code then decides two things the front office owns: what the plan is likely to pay, and which recall type the patient sits on.

CDT is the American Dental Association's code set, revised every year; the ADA's CDT page explains how changes are made. Code names here are short names and everything else is paraphrased. The dentist owns the diagnosis and the plan document owns payment. For how the code set is organized, start with the CDT codes glossary entry.

What is the difference between D4910 and D1110?

The ADA's Guide to Reporting D4346 compares the cleaning codes side by side. Two of its rows, plus the D4910 descriptor the guide reprints, matter at checkout.

• What came before. D1110 follows an oral evaluation. D4910 follows active periodontal therapy: scaling and root planing, gingival flap surgery, or osseous surgery.
• What the patient has. D1110 fits a generally healthy periodontium, including localized gingivitis. D4910 is ongoing therapy for a patient treated for attachment loss, and can include root planing at the sites that need it.
• Who sets the interval. For D4910, the dentist sets it from the clinical evaluation, patient by patient.

D4346 is the other code that gets mixed up here: scaling for generalized moderate or severe gum inflammation with no bone loss. It is therapy, but the ADA guide says D4346 is not followed by D4910. The patient returns to D1110 when the dentist decides the gums have recovered.

Which code does this patient get?

The table maps seven common histories to the code to expect and the front office job. The dentist's documented diagnosis overrides it every time.

The patient who was treated somewhere else

A new patient mentions a deep cleaning years ago at another office. Before the first hygiene visit, request the prior office's procedure codes, dates, and periodontal charting. The dentist uses them, with a periodontal evaluation, to decide between maintenance, therapy again, or D1110. The ADA notes that when a patient is on a new group policy, sending the treatment history with the first D4910 claim helps the payer decide.

Children and teenagers

D1120 is the child prophylaxis. The ADA's coding FAQ says the patient's dentition decides between the adult and child codes, and that a payer applying an age limit should accept the code as submitted and treat the limit as plan design. Plans do set benefits by age, so payment on a correctly coded D1110 for a teenager can still follow the plan's age rule. Verify the rule; keep the code. In OpenDental, the Child Prophy setting attaches child procedures to the recall appointment by an age limit the office picks, so the hygienist confirms the code against the teeth at checkout.

Is it once perio, always perio?

By default, yes: the CDT descriptor, as the ADA's page on D4910 coding for periodontal maintenance describes it, has maintenance following periodontal therapy and continuing for the life of the teeth. Whether a particular patient ever returns to D1110 is the dentist's documented call. The same page notes that the root surfaces therapy leaves exposed are often harder to clean, and the D4346 guide adds that after scaling and root planing, the next treatment is either maintenance or repeated therapy.

The dentist's clinical evaluation also sets the maintenance interval. The front office never switches the code at checkout, whatever the plan pays and however the patient feels about the copay.

The ADA's page reports payers that only pay D4910 within 2 to 12 months of scaling and root planing, payers that require therapy in two or more quadrants first, and payers that pay an adult prophylaxis in its place when their limits apply. That last one is an alternate benefit: the claim still says D4910, because it describes the visit that happened, and the ADA's advice is to tell patients in advance when the plan may not pay.

The patient's history sets the code, and the code sets the recall type. What the plan pays is a separate question, and it never gets to rewrite the first two.

What should you verify on the insurance breakdown?

The ADA's D4910 page says each carrier seems to have its own policy. For example, Delta Dental of Michigan's clinical criteria make periodontal maintenance eligible for benefits only after surgical or nonsurgical periodontal treatment, with the interval set by the patient's condition, risk and prognosis. Other payers write their own rules, so the table lists questions, not answers. Ask each by code, and again when the plan changes.

The ADA's D4910 page reports, from the payer side, that most payers require a waiting period of 8 to 12 weeks after therapy, though the code set names no time frame, so a visit booked inside the window can be denied while coded correctly. If D4910 will be paid as a prophy, or not at all, give the patient the expected cost when you book. The rest of the workflow is in our insurance verification workflow and printable form; this table is its perio page.

Why does the code change the recall list?

The code decides the recall type, the dentist sets the interval for that type, and the interval decides when a patient comes due. Hygiene recall works only when every patient is on the right schedule: prophy patients on the office's prophy interval (OpenDental's recall types manual calls 6 months plus 1 day a common one), perio maintenance patients on the interval the dentist sets, commonly shorter. A perio patient on the prophy interval gets called months late. A prophy patient on the perio interval gets called early, straight into a frequency limit.

In OpenDental, the recall type is set by hand

Per the OpenDental manual, every patient starts with a prophy recall and is moved to perio with the Set Perio button in the Recalls for Patient window (double-click the Recall grid in the Family module), which updates due dates to the perio interval. The due date is the previous recall date plus the interval, so check the new date after clicking. If it is already past, or falls before the dentist wants the first maintenance visit or inside the plan's waiting period, change the Actual Due Date. Prophy and perio are mutually exclusive recall types whose trigger procedures cross over: completing a prophy or perio trigger procedure resets whichever of the two types the patient has. That is where the drift comes from: if nobody clicks Set Perio after scaling and root planing, the patient gets D4910 in the chair and keeps coming due on the prophy interval.

OpenDental's Recall List filters by Perio, Prophy, or All and shows each patient's type and interval as columns. For default intervals and the Sync button, see how to set up and run the recall list in OpenDental.

A monthly check that catches the drift

Once a month, per office, one named person does three things:

• Run the Daily Procedures Report for the past month, filtered to D4341, then D4342, then any perio surgery codes your dentists use. That is everyone who had therapy completed.
• Open each of those patients' Recall grid. The type should say Perio, and the interval should match the dentist's note.
• Run the same report for D4910 and spot-check a handful. Any maintenance patient still on the prophy type goes on one fix list, owned by one person.

A single office can settle this across the hall. In a group, each office drifts its own way unless someone owns the check, so run it per office and report it the same way everywhere. It also makes a good first week for a Dental Hygiene Month recall plan, which starts by cleaning up the recall list.

What the call list inherits from the recall type

Any recall list is only as accurate as the recall type behind it, including ours. MyDentalForce Patient Outreach builds one ranked daily call list per office from that office's own OpenDental, covering due and overdue hygiene recall, unscheduled treatment and lapsed patients, rebuilt every morning. What the list adds is follow-through: every call outcome is logged and written back to OpenDental, and managers see each office's activity and results without asking. MyDentalForce runs the daily operations of a 19-office group in Houston; because the list is built per office, a single office gets the same list.

Take the decision table to your next hygiene meeting and run it like the D9430 coding quiz: read a row, ask who would have posted it differently, and settle it with the dentist in the room. Then run the monthly check once; it separates a perio interval on paper from a perio patient who comes back on time.