ServicesDental answering serviceDental virtual assistantRevenue cycle managementInsurance verificationA/R recoveryPatient recallDentrix AscendOpen DentalDental codesResourcesBook a call
Dental codes

Dental codes, organised the way claims fail.

The CDT code set has twelve service categories. Knowing which one a procedure sits in tells you the code. Knowing what that category is known for tells you whether the claim gets paid. This covers both.

Hand the follow-up to us
The code set

The twelve CDT categories

Codes are grouped by service type. The ranges below are stable across annual revisions even though individual codes inside them are not.

D0100–D0999DiagnosticExams, radiographs, photographs and diagnostic tests — the codes that open almost every claim and set up everything billed after them.Where it goes wrong: Frequency limits. Exams and images are the most frequency-restricted codes in dentistry, and the limit is per plan rather than per calendar year. Verification that does not capture image history is where this series turns into a write-off.
D1000–D1999PreventiveCleanings, fluoride, sealants and space maintainers. High volume, low value individually, and the backbone of a recall schedule.Where it goes wrong: Age limits and the adult-versus-child distinction. Sealants and fluoride commonly carry an age cut-off, and prophylaxis is split by patient age in a way that gets coded on autopilot and denied on review.
D2000–D2999RestorativeFillings, crowns, build-ups, inlays and onlays. Coded by surface count and material, both of which change the fee.Where it goes wrong: Downgrades. A posterior composite reimbursed at the amalgam rate is the single most common surprise on a restorative EOB, and the patient was usually quoted the composite fee.
D3000–D3999EndodonticsRoot canals, pulpotomies, apicoectomies and retreatment, coded by tooth type and canal count.Where it goes wrong: Bundling with the restoration that follows. Build-ups and posts billed the same day as endodontic therapy are frequently bundled, and whether they are depends on the contract rather than the clinical reality.
D4000–D4999PeriodonticsScaling and root planing, surgical periodontal treatment, and periodontal maintenance.Where it goes wrong: The single richest source of denials in dental billing. Payers want charting that justifies the diagnosis, quadrant counts that match the tooth count, and a defensible interval between therapy and maintenance.
D5000–D5899Prosthodontics, removableComplete and partial dentures, relines, rebases and repairs.Where it goes wrong: Replacement clauses and waiting periods. A denture is commonly replaceable only on a multi-year cycle, and the clock runs from the prior placement — which may have happened at another practice entirely.
D5900–D5999Maxillofacial prostheticsProstheses for patients following surgery or trauma. Low volume, high value, and often medically rather than dentally billed.Where it goes wrong: Frequently a medical claim rather than a dental one. Sending it to the dental plan by default is how these sit unpaid for months.
D6000–D6199Implant servicesImplant placement, abutments, implant-supported crowns and their maintenance.Where it goes wrong: Missing-tooth clauses and whether the plan covers implants at all. Verification that confirms only 'major coverage' without confirming implants specifically is not verification.
D6200–D6999Prosthodontics, fixedBridges — pontics, retainers and abutment crowns, coded per unit.Where it goes wrong: Unit counting. A bridge is several codes, not one, and a missing-tooth clause can void the whole case regardless of clinical need.
D7000–D7999Oral and maxillofacial surgeryExtractions, surgical extractions, biopsies, bone grafts and related procedures.Where it goes wrong: The simple-versus-surgical extraction distinction, which turns on what was actually done rather than what was planned. The narrative has to support the code, and grafts often need a separate medical determination.
D8000–D8999OrthodonticsLimited, interceptive and comprehensive treatment, plus retention.Where it goes wrong: Lifetime maximums and the fact that orthodontic benefits are usually paid on an instalment schedule rather than up front. Posting those instalments correctly is where practices lose track.
D9000–D9999Adjunctive general servicesSedation, palliative treatment, occlusal guards, office visits and the unclassified codes.Where it goes wrong: The unspecified-procedure codes in this range need a narrative every time. Submitted without one they are denied by default, not reviewed.
Two things worth knowing

Codes change every January

The CDT set is revised annually, effective 1 January. Codes are added, revised and deleted each year, which is why a team working from an old cheat sheet starts producing avoidable denials in the first quarter. Work from a current licensed copy of the code book, published by the American Dental Association.

We deliberately do not reproduce the official code descriptors on this site. They are the ADA’s copyrighted work and licensed commercially. What we can add is the part the code book does not: which pairings get bundled, what documentation a payer expects, and which limit decides the outcome before anyone reads the clinical notes.

Guides

By procedure

D4341, D4342, D4346, D4355, D4910Periodontal codes: SRP, debridement and maintenanceRead
Related

Next door to this

GlossaryDental billing and insurance termsThe vocabulary around the codes — frequencies, downgrades, timely filing, coordination of benefits.Read ServiceOutsourced dental billingWhen coding accuracy is not the problem and follow-up is, this is the part we take over.Read
What is a CDT code?

CDT stands for Current Dental Terminology. It is the code set used to report dental procedures on claims in the United States, maintained and published by the American Dental Association and revised annually. Every procedure billed to a dental plan is reported with one.

What is the difference between CDT and CPT codes?

CDT codes report dental procedures on dental claims. CPT codes report medical procedures on medical claims. The distinction matters in practice because some dental work — surgical extractions, biopsies, appliances for sleep apnoea, trauma — is often more appropriately billed to medical, and sending it to the dental plan by default is a common reason those claims sit unpaid for months.

How often do dental codes change?

The CDT code set is revised annually and takes effect on 1 January. Codes are added, revised and deleted each year. This is why a team working from a cheat sheet printed two years ago starts producing avoidable denials in the first quarter — the code did not become wrong, it stopped existing.

Why does this page not list every code with its official description?

Because the CDT code set is copyrighted by the American Dental Association and licensed commercially. Code numbers are facts and we reference them freely, but reproducing the official descriptors wholesale is not ours to republish. The ADA publishes the authoritative list, and any practice billing dentistry should be working from a current licensed copy rather than from a blog post. What we add is the part the code book deliberately does not cover: which pairings get bundled, what documentation the payer actually wants, and which limit decides the outcome.

Which code series causes the most denials?

Periodontics, by a distance. Scaling and root planing, and the periodontal maintenance that follows, need charting that supports the diagnosis, quadrant counts that match the tooth count, and a defensible interval between therapy and maintenance. Diagnostic codes are a close second, where frequency limits rather than clinical judgement decide whether the claim pays.

Let's talk

Ready to stop losing money
at the front desk?

Tell us which locations you run and which system you're on. We'll show you exactly what we'd take over first.

Book a call
Let's talk

Ready to stop losing money
at the front desk?

Tell us which locations you run and which system you're on. We'll show you exactly what we'd take over first.

Book a call