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Gregory K. An, DDS, MPH

Endodontics in Redwood City, CA · enumerated 2006.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1902870587

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Registry record

Entity type Individual (Type 1)
Name Gregory K. An
Credential DDS, MPH
Sex Male
Practice address 1690 Woodside Rd, Suite 209, Redwood City, CA, 94061
Enumeration date Feb 13, 2006
Last updated in NPPES Jan 13, 2014

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 20019 (MA) Secondary
1223P0221X Pediatric Dentistry Dental Providers · License 20019 (MA) Secondary
1223E0200X Endodontics Dental Providers · License 59088 (CA) Primary
DDS · Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS credential

Other identifiers

Identifier Type State Issuer
HV0085 Other MA HARVARD PILGRIM

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Gregory An?
Gregory An is registered in NPPES with the primary taxonomy of Endodontics. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-01-13.