Gregory Duffner, D.D.S.
NPI 1225340375 · General Practice Dentistry · Homewood, IL
Gregory Duffner, D.D.S. is a General Practice Dentistry provider in Homewood, IL (NPI 1225340375).
Provider details
- NPI number
- 1225340375
- Entity type
- Individual
- Primary specialty
- General Practice DentistryDental Providers
- Credential
- D.D.S.
- Sex
- Male
- Sole proprietor
- No
- License
- 019-019782 (IL)
Specialties & taxonomies
Dental Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
15 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 1 distinct drug on file.
| Drug | Part D claims (2024) |
|---|---|
| Amoxicillin | 13 |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means no Part D record, never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Practice location
Mailing address
Registry dates
- Enumerated
- 2010-07-06
- Last updated
- 2025-10-23
- Certified
- 2025-10-23
Frequently asked questions
- What is Gregory Duffner's NPI number?
- Gregory Duffner's National Provider Identifier (NPI) is 1225340375, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gregory Duffner's specialty?
- Gregory Duffner is listed in the NPPES registry with a primary specialty of General Practice Dentistry (Dental Providers).
- Where is Gregory Duffner located?
- Gregory Duffner's practice location on file with NPPES is 18040 Park Ave, Homewood, IL 60430-1606.
- What is Gregory Duffner's phone number?
- The practice phone number listed in the NPPES registry for Gregory Duffner is (708) 792-2779.
- Is Gregory Duffner's NPI active?
- Yes — Gregory Duffner's NPI (1225340375) is active in the NPPES registry as of the last update on 2025-10-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.