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Dr. Gianh Nguyen Portnoy, DDS

General Practice Dentistry in Okemos, MI · enumerated 2007.

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

National Provider Identifier

1336363993

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Registry record

Entity type Individual (Type 1)
Name Dr. Gianh Nguyen Portnoy
Credential DDS
Sex Female
Practice address 1738 Hamilton Rd, Okemos, MI, 48864
Phone (517) 349-3266
Fax (517) 381-2457
Enumeration date Apr 12, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 2901018167 (MI) 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
1316952732 Other MI PORTNOY AND TU DDS PC

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

Where does Gianh Portnoy practice?
The practice location on file with NPPES is in Okemos, MI. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Gianh Portnoy?
The National Provider Identifier (NPI) for Gianh Portnoy is 1336363993, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.