Garrett Brennan, DDS
Garrett Brennan, DDS is a provider specialising in Pediatric Dentistry in New London, CT, registered under NPI 1255320784.
Getting there
The practice address on file is 190 HEMPSTEAD ST, New London, CT 06320. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 5990 | CT | Pediatric Dentistry primary |
This provider holds licence 5990 issued in CT. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Pediatric Dentistry covers
An age-defined specialty that provides both primary and comprehensive preventive and therapeutic oral health care for infants and children through adolescence, including those with special health care needs. NUCC Health Care Provider Taxonomy, code 1223P0221X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1255320784 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 18, 2005 |
| Last updated | Jul 13, 2026 |
| Status | Active |
| Sole proprietor | No |
| Gender | Male |
| Credential | DDS |
| Practice address |
190 HEMPSTEAD ST New London, CT 06320 (860) 447-3216 Fax (860) 701-6019 |
| Other identifiers |
2059905
· Medicaid (CT) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 2 | 5 | 5 | 3 | 2 | 0 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 2 | 1 | 5 | 6 | 2 | 0 | 7 | 7 |
Sum = 56 · next multiple of 10 = 60 · check digit = 4 · actual last digit = 4
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.