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DR. GREGORY JAMES THOMAS DDS, MS
NPI 1912947227
Oral & Maxillofacial Surgery in Warren, MI

Active since June 07, 2006PECOS Enrolled
29427 RYAN RD, WARREN, MI 48092(586) 755-9340(586) 755-1081 Get Directions Write a Review

NPPES record last updated: August 10, 2015. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Gregory James Thomas Dds, Ms NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. GREGORY JAMES THOMAS DDS, MS (NPI 1912947227) is an individual oral & maxillofacial surgery provider in Warren, Michigan, licensed in Michigan (2901013883) and active in the NPI registry since June 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1912947227
Entity TypeIndividualMale
Primary Taxonomy204E00000X
Provider Legal NameDR. GREGORY JAMES THOMASCredential: DDS, MS
Location Address29427 RYAN RDWarren, MI 48092-2203
Mailing Address29425 Ryan RdWarren, MI 48092-2203 · (586) 755-9340 · Fax (586) 755-9341
Phone(586) 755-9340
Fax(586) 755-1081
Sole ProprietorNo
Enumeration DateJune 7, 2006
Last NPPES UpdateAugust 10, 2015
✔ NPI 1912947227 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyOral & Maxillofacial SurgeryAllopathic & Osteopathic Physicians
Taxonomy Code204E00000X
License✔ Licensed in MI · 2901013883
Definition
Oral and maxillofacial surgeons are trained to recognize and treat a wide spectrum of diseases, injuries and defects in the head, neck, face, jaws and the hard and soft tissues of the oral and maxillofacial region. They are also trained to administer anesthesia, and provide care in an office setting. They are trained to treat problems such as the extraction of wisdom teeth, misaligned jaws, tumors and cysts of the jaw and mouth, and to perform dental implant surgery.
Also ListedDentist · Oral and Maxillofacial SurgeryTaxonomy 1223S0112X · License 2901013883 (MI)
29427 RYAN RD, Warren, MI 48092
Open in Google Maps ↗

Other Identifiers 3

Medicare UPINT97261MI
Other970E07680MI · Blue Cross Pin
Medicare ID-Type Unspecified0E0768003MI

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Cross and Blue Shield of Montana, Blue Cross and Blue Shield of Oklahoma, Blue Cross and Blue Shield of Texas and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Gregory James Thomas Dds, Ms is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Gregory Thomas reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Summit Oral & Maxillofacial Surgery PC
Same address
Oral and Maxillofacial Surgery
29427 RYAN RD
Warren, MI 48092
  • Reassigned Medicare billing, Michigan enrollment
  • 8 clinicians in this Medicare group
NPI 1811066129 (586) 755-9340

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Other Providers at the Same Location NPPES 7

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. DAVID SCOTT COVIAK D.D.S., M.D.
Dentist (Oral and Maxillofacial Surgery)
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340
DR. NICOLETTE DIANE ESSIAN DMD
Dentist (Oral and Maxillofacial Pathology)
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340
DR. MICHAEL BARTHOLOMEW KRAEMER DMD, MD
Oral & Maxillofacial Surgery
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340
ARSHI S LEHAL MD
Oral & Maxillofacial Surgery
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340
DR. JOHN MASON HACKENBERGER DDS
Dentist (Oral and Maxillofacial Surgery)
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340
SUMMIT ORAL & MAXILLOFACIAL SURGERY PC
Dentist (Oral and Maxillofacial Surgery)
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340
DR. SHYAM PRASAD ARAVINDAKSHA BDS, MDS
Oral & Maxillofacial Surgery
29427 RYAN RD
WARREN, MI 48092
Macomb County (586) 755-9340

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Gregory Thomas's NPI number?

The NPI number for Gregory Thomas is 1912947227. It was assigned to this individual provider in the NPPES registry on June 7, 2006.

Where is Gregory Thomas located?

Gregory Thomas practices at 29427 Ryan Rd, Warren, MI 48092. The listed phone number is (586) 755-9340.

What is Gregory Thomas's specialty?

The primary specialty registered for this NPI is Oral & Maxillofacial Surgery with taxonomy code 204E00000X.

Is Gregory Thomas enrolled in Medicare?

Yes. Gregory Thomas is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Gregory Thomas's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Thomas reassigns Medicare benefits to Summit Oral & Maxillofacial Surgery PC (Warren, MI). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Gregory Thomas's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Gregory Thomas accept?

Health plans from Blue Cross Blue Shield of Michigan Mutual Insurance Company, Blue Cross and Blue Shield of Montana, Blue Cross and Blue Shield of Oklahoma, Blue Cross and Blue Shield of Texas and HRI Dental & Vision and 2 other insurers list Gregory Thomas as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Gregory Thomas was last updated on August 10, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.