Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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Dr. Gregory Thaddeus St Clair, DDS

Individual provider General Practice Dentistry · NPI 1104919463

Dr. Gregory Thaddeus St Clair, DDS is a General Practice Dentistry in Port Jefferson, New York. Practices as a sole proprietor. Licensed in New York.

Licensed in
NY
In the registry since
2006
What do these letters mean?
DDS — Doctor of Dental Surgery
A dentist. DDS and DMD are the same qualification — universities choose which title to award.

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Practice location Address checks out

101 Hoyt Ln
Port Jefferson, NY 11777-1318
Phone: (631) 928-1957
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

General Practice Dentistry (primary) Taxonomy 1223G0001X · Licence 043675 (NY)

Record details

NPI number1104919463
Entity typeIndividual (Type 1)
GenderMale
Credentials DDS
Sole proprietorYes
NPI enumeratedOctober 1, 2006
Last updated in NPPESJuly 8, 2007
Mailing address101 Hoyt Ln, Port Jefferson, NY 11777-1318

Other providers in Port Jefferson