2026 NPPES data Endodontics NPI 1265614861 D.D.S.
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MARK GROSKO, D.D.S.

Endodontics in NEWARK, Ohio. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
330
Medicare Part D claims · 173 beneficiaries · Endodontics avg: 116
What the federal data reveals: MARK GROSKO, D.D.S. is a Endodontics ([object Object]) practicing in NEWARK, Ohio with a Medicare Part D prescribing footprint of 330 claims across 173 beneficiaries .

What stands out: MARK GROSKO, D.D.S. filed 330 Medicare Part D claims in 2023 across NEWARK, Ohio. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

MARK GROSKO, D.D.S. at a glance

Quality data not reported

NPI registry status

Active

Issued 12/05/2007

NPI 1265614861

Primary specialty

Endodontics

Mid-sized

5,856 US NPIs in this specialty

Medicare Part D claims

330 184% vs specialty avg

2023 prescription claims

Specialty avg: 116

Specialty distribution in Ohio

How Endodontics compares to other specialties among Ohio providers

Ohio providers

Endodontics share within Ohio

1. Endodontics42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Endodontics share within Ohio

Specialty board-certification context

Estimated specialty board-certified rate — Endodontics (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Endodontics ABMS/AOA estimate

Est. board-certified rate (Endodontics) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Endodontics) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

MARK GROSKO, D.D.S. is a Endodontics provider practicing in NEWARK, Ohio, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: D.D.S.. NPI: 1265614861. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

MARK GROSKO, D.D.S. appears in the CMS NPPES registry as a Endodontics provider holding D.D.S. credentials at 843 N 21ST ST, NEWARK, OH, 43055, with a listed phone of (740) 344-6349. NPI 1265614861 was issued on 12/05/2007. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GROSKO most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 330 prescription claims written by this provider, covering 173 Medicare beneficiaries and totaling roughly $2K in drug spend, with an opioid prescribing rate of 16.7%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Endodontics is a mid-sized specialty nationwide, with 5,856 enrolled providers across 53 states and an average of 116 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

843 N 21ST ST
NEWARK, OH 43055

Provider Details

NPI 1265614861
Specialty Endodontics
Credentials D.D.S.
Gender Male
NPI Issued 12/05/2007

License & disciplinary context — Ohio OMB 2023 annual report

Aggregate state board data only — NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~48K Ohio medical licensees in 2023 — they are NOT specific to MARK GROSKO, D.D.S.. To verify MARK GROSKO, D.D.S.'s current license status, search the OMB public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

158
Total board actions, Ohio 2023
Across 154 cases
3.29
Actions per 1,000 licensees
Ohio statewide rate
probation
Most common action type
56 cases

OMB publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Ohio disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

330
Total Claims
$2K
Total Drug Cost
173
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
330
Total Day Supply
2,002
Generic Drug Cost
$2K
Opioid Claims
55 (16.7% rate)
Antibiotic Claims
203

Patient Demographics

Average Patient Age
70.2 years
Avg HCC Risk Score
0.85
Gender Split
50% female / 50% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

Drug Claims
Amoxicillin
130
Clindamycin Hcl
50
Hydrocodone-Acetaminophen
Hydrocodone/Acetaminophen
48
Methylprednisolone
48
Metronidazole
21
Chlorhexidine Gluconate
19

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Endodontics Overview

How MARK GROSKO, D.D.S. fits within the Endodontics landscape nationally.

5,856
Endodontics Providers in US
53
States with Endodontics
116
Avg Claims per Provider

MARK GROSKO, D.D.S.'s 330 claims are above the specialty average of 116.

Nearby Endodontics Providers in Ohio

Other clinicians with the same primary specialty enrolled in Ohio, drawn from the same CMS NPPES roster as GROSKO.

Compare Endodontics nationally: see state-by-state distribution →

Frequently Asked Questions

What is MARK GROSKO, D.D.S.'s specialty?
MARK GROSKO, D.D.S. specializes in Endodontics and practices in NEWARK, Ohio. Credentials: D.D.S..
How much does MARK GROSKO, D.D.S. prescribe under Medicare Part D?
In 2023, MARK GROSKO, D.D.S. wrote 330 Medicare Part D claims totaling $2K in drug costs for 173 beneficiaries.
Where is MARK GROSKO, D.D.S. located?
MARK GROSKO, D.D.S. is located at 843 N 21ST ST, NEWARK, OH, 43055. Phone: (740) 344-6349.
What is MARK GROSKO, D.D.S.'s NPI number?
MARK GROSKO, D.D.S.'s National Provider Identifier (NPI) is 1265614861, issued on 12/05/2007.
Does MARK GROSKO, D.D.S. prescribe opioids?
Yes, MARK GROSKO, D.D.S. had 55 opioid claims in 2023 with an opioid prescribing rate of 16.7%.
How many Endodontics providers are there in the US?
There are 5,856 Endodontics providers across 53 states in the US. The average Endodontics provider writes 116 Medicare Part D claims per year.
What drugs does MARK GROSKO, D.D.S. prescribe most often?
Based on 2023 Medicare Part D data, MARK GROSKO, D.D.S.'s most frequently prescribed drugs include Amoxicillin, Clindamycin Hcl, Hydrocodone-Acetaminophen. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does MARK GROSKO, D.D.S. accept Medicare?
MARK GROSKO, D.D.S. appears in CMS Medicare data with 330 Part D claims and 173 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify MARK GROSKO, D.D.S.'s credentials?
MARK GROSKO, D.D.S.'s NPI is 1265614861 with credentials D.D.S.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology