John Diponziano
Dentist · San Leandro, CANPI 1770569600
Payments from drug & device makers
What this record shows
This record is dominated by speaking fees: $903,503 of the $903,564 with a category attached, or 100.0%. Hiossen, Inc. accounts for 100.0% of it on its own, with 1 other manufacturer making up the rest. Reporting peaked in 2023 at $175,178 and has fallen 79.1% since, to $36,608 in 2025. Among dentist clinicians in CA with any reported payments, this total sits in the top 5% — high for the specialty, which is a reason to read the composition above rather than the number alone.
Across 8 payments — averaging $112,945 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Hiossen, Inc.$904K
- Straumann USA LLC$61
What the payments were for
- Speaking & faculty fees$903,503100%
- Food & beverage$610%
General payments by program year
Who reported the general payments
Companies are grouped under their corporate parent — a single manufacturer often files under several CMS reporting entities. Research and ownership payments are counted separately and are not in this table.
| Company | Payments | Total |
|---|---|---|
| Hiossen, Inc. | 7 | $903,503 |
| Straumann USA LLC | 1 | $61 |
How this compares
$903,564 in reported general payments places this provider in the 95th percentile of 9,550 dentist providers in California.
Other dentist in San Leandro
- Todd EngelLadera Ranch$4.2M
- Jedediah HussThousand Oaks$1.3M
- Jeffrey RohdeSanta Barbara$593K
- Troy SchueddingWalnut Creek$468K
- Todd SnyderLaguna Niguel$427K
- Saima HasnainSacramento$415K
- August de OliveiraEncino$332K
- Brian NovyNewhall$297K
- Christopher HagenFountain Valley$289K
- Janice WangWalnut Creek$287K
Where these figures come from
- Payments: CMS Open Payments, program years 2019–2025 (publication P06302026_06032026).
- Identity: NPPES NPI Registry, July 2026.