William Arden, DDS, PHD, DMSC, MPH
William Arden, DDS, PHD, DMSC, MPH is a provider specialising in Endodontics in Bethesda, MD, registered under NPI 1285912154. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 8955 WOOD RD, Bethesda, MD 20889. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 27167 | TX | Endodontics primary |
| DEN03439 | RI | Endodontics |
| DN1857462 | MA | Endodontics |
| VA-0013 | MD | Endodontics |
| 27167 | TX | General Practice Dentistry |
| DN1857462 | MA | Dentist |
Licences are recorded in 4 states: TX, RI, MA, MD. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
- Status
- Approved
- Provider type
- Order And Referring Only - Dentist
- PAC ID
- 5799065876
- Enrollment ID
- I20161207000396
Medicare enrolment is recorded as approved under the provider type Order And Referring Only - Dentist. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
Licensed in 4 states
This provider holds licences in 4 states: Massachusetts, Maryland, Rhode Island and Texas. The practice address on file is in Bethesda, MD, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Endodontics covers
The branch of dentistry that is concerned with the morphology, physiology and pathology of the human dental pulp and periradicular tissues. Its study and practice encompass the basic and clinical sciences including biology of the normal pulp, the etiology, diagnosis, prevention and treatment of diseases and injuries of the pulp and associated periradicular conditions. NUCC Health Care Provider Taxonomy, code 1223E0200X
All registered taxonomy codes
This provider registers 6 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 1223E0200X | Endodontics Endodontics | 27167 | TX | primary |
| 1223E0200X | Endodontics Endodontics | DEN03439 | RI | |
| 1223E0200X | Endodontics Endodontics | DN1857462 | MA | |
| 1223E0200X | Endodontics Endodontics | VA-0013 | MD | |
| 1223G0001X | General Practice Dentistry General Practice | 27167 | TX | |
| 122300000X | Dentist | DN1857462 | MA |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1285912154 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 26, 2011 |
| Last updated | Jan 15, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | DDS, PHD, DMSC, MPH |
| Practice address |
8955 WOOD RD Bethesda, MD 20889 (301) 295-8051 |
| Mailing address |
1960 MENDON RD Cumberland, RI 02864 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 2 | 8 | 5 | 9 | 1 | 2 | 1 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 2 | 7 | 5 | 9 | 1 | 4 | 1 | 1 |
Sum = 56 · next multiple of 10 = 60 · check digit = 4 · actual last digit = 4
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.