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Dr. John Fred Cassiani, DDS

General Practice Dentistry in Downers Grove, IL · enumerated 2007 · practices at Robert C Poulsom DDS Ms Ltd.

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

National Provider Identifier

1184820375

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Registry record

Entity type Individual (Type 1)
Name Dr. John Fred Cassiani
Credential DDS
Sex Male
Practice address 6800 S Main St, #211, Downers Grove, IL, 60516
Phone (630) 852-8855
Enumeration date Jun 25, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 1915958 (IL) Primary
DDS · Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS credential

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 John Cassiani practice?
The practice location on file with NPPES is in Downers Grove, IL. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for John Cassiani?
The National Provider Identifier (NPI) for John Cassiani is 1184820375, a Type 1 (individual) record in the CMS NPPES registry.

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