Washington was first, authorizing hygienists to administer local anesthesia in 1971.
Delaware is the most recent, in 2025.
Between those two dates, adoption came in waves: eight states in the 1970s, a slower six through the 1980s, a dozen more in the 1990s, then the chart's busiest stretch — 19 states in the 2000s.
The ADHA's December 2025 chart lists an implementation year for all 50 states plus DC; confirm your state's current rule with its dental board.
The short answer
The ADHA's Local Anesthesia Administration by Dental Hygienists chart (revised December 2025) records an implementation year for every one of the 50 states plus DC — 51 rows in all.
The earliest is Washington, in 1971.
The most recent is Delaware, in 2025, and even that date comes with a caveat: the chart lists Delaware's exam and course requirements as "Pending Board Regulations," meaning the state authorized the practice before finishing the rules that govern it.
This article covers only the chart's State & Year Implemented column — the history of when.
For whether your state currently allows it at all, and under what supervision, see can a dental hygienist administer local anesthesia — that article owns the national yes-or-no question.
Informational only — confirm with your state board
The 1970s: the first states to authorize it
Local anesthesia authority for hygienists is younger than licensure itself — no state authorized it before 1971.
Eight states acted in that decade, the chart's first wave:
- Washington — 1971
- New Mexico — 1972
- Missouri — 1973
- Idaho — 1975
- Oregon — 1975
- Arizona — 1976
- California — 1976
- Colorado — 1977
Local anesthesia is most often used alongside scaling and root planing — but the ADHA tracks the two as separate chart rows, so an early adoption date for one says nothing about the other.
The 1980s: six more states
The pace slowed through the 1980s.
Six states authorized local anesthesia in this decade:
- Oklahoma — 1980
- Alaska — 1981
- Nevada — 1982
- Utah — 1983
- Montana — 1985 (chart also lists 2017 — see below)
- Hawaii — 1987
Montana is the chart's only dual-date entry: its State & Year Implemented cell reads 1985/2017 — two separate implementation dates, quoted as written, not a range.
The extract doesn't specify what distinguishes the two; confirm with Montana's dental board which milestone each date reflects.
The 1990s: a dozen more states
Twelve states authorized local anesthesia in the 1990s:
- Wyoming — 1991
- South Dakota — 1992
- Kansas — 1993
- Vermont — 1993
- Arkansas — 1995
- Minnesota — 1995
- Nebraska — 1995
- South Carolina — 1995
- Maine — 1997
- Iowa — 1998
- Louisiana — 1998
- Wisconsin — 1998
By the end of 1998, 26 of the 51 jurisdictions the chart tracks had authorized the practice — just over half.
The 2000s: the busiest decade
The 2000s brought the chart's largest single-decade wave — 19 states authorized local anesthesia between 2000 and 2009:
- Illinois — 2000
- New York — 2001
- Kentucky — 2002
- Michigan — 2002
- New Hampshire — 2002
- Mississippi — 2003
- North Dakota — 2003
- West Virginia — 2003
- District of Columbia — 2004
- Massachusetts — 2004
- Tennessee — 2004
- Connecticut — 2005
- Rhode Island — 2005
- Ohio — 2006
- Virginia — 2006
- Indiana — 2008
- New Jersey — 2008
- Maryland — 2009
- Pennsylvania — 2009
By the end of 2009, 45 of the 51 jurisdictions the chart tracks had authorized the practice.
2010s to 2020s: the most recent additions
Only six jurisdictions authorized local anesthesia after 2009:
- Florida — 2012
- Alabama — 2018
- North Carolina — 2021
- Georgia — 2023
- Texas — 2023
- Delaware — 2025
Georgia and Texas share the same year, 2023, quoted as written on the chart.
Delaware's 2025 authorization is the newest, and its exam and course-requirement cells read "Pending Board Regulations" rather than a finished figure — the state authorized the practice before publishing the rules a hygienist would need to meet to use it.
That's a live process, not a chart error; confirm current status with Delaware's board before relying on it.
Every state's year, at a glance
Quoting the chart's State & Year Implemented column as written, for all 51 jurisdictions it tracks:
| State | Year implemented (ADHA chart) |
|---|---|
| Alabama | 2018 |
| Alaska | 1981 |
| Arizona | 1976 |
| Arkansas | 1995 |
| California | 1976 |
| Colorado | 1977 |
| Connecticut | 2005 |
| Delaware | 2025 |
| District of Columbia | 2004 |
| Florida | 2012 |
| Georgia | 2023 |
| Hawaii | 1987 |
| Idaho | 1975 |
| Illinois | 2000 |
| Indiana | 2008 |
| Iowa | 1998 |
| Kansas | 1993 |
| Kentucky | 2002 |
| Louisiana | 1998 |
| Maine | 1997 |
| Maryland | 2009 |
| Massachusetts | 2004 |
| Michigan | 2002 |
| Minnesota | 1995 |
| Mississippi | 2003 |
| Missouri | 1973 |
| Montana | 1985 / 2017 |
| Nebraska | 1995 |
| Nevada | 1982 |
| New Hampshire | 2002 |
| New Jersey | 2008 |
| New Mexico | 1972 |
| New York | 2001 |
| North Carolina | 2021 |
| North Dakota | 2003 |
| Ohio | 2006 |
| Oklahoma | 1980 |
| Oregon | 1975 |
| Pennsylvania | 2009 |
| Rhode Island | 2005 |
| South Carolina | 1995 |
| South Dakota | 1992 |
| Tennessee | 2004 |
| Texas | 2023 |
| Utah | 1983 |
| Vermont | 1993 |
| Virginia | 2006 |
| Washington | 1971 |
| West Virginia | 2003 |
| Wisconsin | 1998 |
| Wyoming | 1991 |
Source: ADHA Local Anesthesia Administration by Dental Hygienists – State Chart, revised December 2025.
How this fits with the rest of the chart
This article covers only the ADHA chart's State & Year Implemented column — a timeline of adoption, not a ranking of it.
Being an early or late adopter says nothing about a state's current supervision level, exam requirement, or required course hours; each of those is its own separate column on the same chart.
For whether your state currently allows local anesthesia at all, see can a dental hygienist administer local anesthesia — that article owns the national yes-or-no question.
This one only answers when.
Local anesthesia is also a distinct chart row from broader practice questions like direct access (working without a dentist present at all, across any procedure) and from the clinical procedure it's most often paired with, scaling and root planing.
Confirm your state's exact rule
An implementation year tells you when a state first authorized the practice — it doesn't tell you the current supervision level, exam requirement, or course hours, and an older authorization year doesn't necessarily mean looser current rules.
Practice acts are amended long after their original authorization date without changing the year this chart lists.
Start with your state dental board's practice act for the current rule, and see our dental hygienist jobs page to find openings once you've confirmed your certification.
This article is general information, not legal or clinical advice. Scope-of-practice, supervision, and authorization rules vary by state and change over time — confirm current requirements with your state dental board.