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Gastroenterology

Henry S. Dinneen, DO

Works at hospitals in Pompton Plains, NJ · Morristown, NJ · Newton, NJ · New Jersey

Summary

Dr. Henry S. Dinneen, DO is a gastroenterologist at 100 Madison Ave, Morristown, NJ 07960. Phone: (973) 971-5596. Accepts Medicare assignment. In 2024, Henry S. Dinneen had 425 Original Medicare patients and 802 services. NPI 1417247784. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Gastroenterologist (Medicare lists Gastroenterology)
  • Address: 100 Madison Ave, Morristown, NJ 07960 · Directions (1 more location)
  • Phone: (973) 971‑5596
  • Medicare: Accepts Medicare assignment
  • Hospitals: Chilton Medical Center, Morristown Medical Center, Newton Medical Center
  • Group practice: Practice Associates Medical Group
  • Medical school: University Of New England, College Of Osteo Medicine · graduated 2011 (15 years since medical school)
  • Gender (as listed): Male
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Henry S. Dinneen, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Henry S. Dinneen accept Medicare assignment?
Yes. Medicare's clinician data says Henry S. Dinneen accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Henry S. Dinneen see?
In 2024, CMS data shows 425 Original Medicare patients and 802 services for Henry S. Dinneen. This counts Original Medicare only and measures volume, not quality.
What is Henry S. Dinneen's NPI number?
1417247784. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Henry S. Dinneen, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients425
Services billed to Medicare802
Different services or procedures42
Participating Medicare providerYes
Average age of these patients73

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)114 services
  2. Removal of polyps or growths of large bowel using an endoscope with mechanical snare (45385)92 services
  3. Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)77 services
  4. Biopsy of large bowel using a flexible endoscope (45380)72 services
  5. Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)72 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Arthritis51%
  • Ischemic heart disease37%
  • Diabetes35%
  • Anxiety32%

Hospitals where Henry S. Dinneen works

Medicare's Facility Affiliation Data lists Henry S. Dinneen at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

  • Chilton Medical CenterPompton Plains, NJ · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 310017
  • Morristown Medical CenterMorristown, NJ · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 310015
  • Newton Medical CenterNewton, NJ · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 310028

Practice locations

Addresses where Henry S. Dinneen is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Henry S. Dinneen as a member of this group (CMS data updated October 2, 2026).

  • Practice Associates Medical Group1,408 clinicians in the group

Specialties

Find other Gastroenterology doctors in New Jersey →

Other gastroenterologists in Morristown

Clinicians with the same Medicare primary specialty in Morristown, NJ — not a recommendation.

All gastroenterologists in Morristown →

Other clinicians in Practice Associates Medical Group

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialDO
Medical schoolUniversity Of New England, College Of Osteo Medicine
Graduation year2011 (15 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1417247784
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians