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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Mark L Grosko, D.D.S.

Endodontics in Newark, OH · enumerated 2007 · practices at Mark L Grosko DDS Inc.

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

National Provider Identifier

1265614861

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark L Grosko
Credential D.D.S.
Sex Male
Practice address Newark, OH, 43055
Phone (740) 344-6349
Fax (740) 344-6350
Enumeration date Dec 5, 2007
Last updated in NPPES Sep 27, 2011

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

1223E0200X Endodontics Dental Providers · License 21555 (OH) 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
440265 Other OH SUPERIOR DENTAL
2424693 Medicaid OH -
256022 Other OH CIGNA
9185647 Other OH DORAL
1400162 Other OH UNITED CONCORDIA
187028 Other OH COMP BENEFITS
25 1901759027 Other OH CARESOURCE

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 Mark Grosko practice?
The practice location on file with NPPES is in Newark, OH. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Grosko?
The National Provider Identifier (NPI) for Mark Grosko is 1265614861, 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 2011-09-27.