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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Leonard Lem, M.D., D.D.S.

Oral and Maxillofacial Pathology Dentistry in Arcadia, CA · enumerated 2006.

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

National Provider Identifier

1356357636

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Registry record

Entity type Individual (Type 1)
Name Dr. Leonard Lem
Credential M.D., D.D.S.
Sex Male
Practice address Arcadia, CA, 91007
Phone (626) 821-9633
Fax (626) 821-9697
Enumeration date Jul 31, 2006
Last updated in NPPES Jul 8, 2007

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

1223P0106X Oral and Maxillofacial Pathology Dentistry Dental Providers · License 35519 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
B3551901 Other CA DENTI-CAL PROVIDER ID

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

What is the NPI number for Leonard Lem?
The National Provider Identifier (NPI) for Leonard Lem is 1356357636, a Type 1 (individual) record in the CMS NPPES registry.
Where does Leonard Lem practice?
The practice location on file with NPPES is in Arcadia, CA. Providers can have multiple locations; NPPES lists the primary practice address.

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