Dental Hygiene Prerequisites: What Classes You Need
The classes most dental hygiene programs require, typical credits, GPA and entrance exam rules, and which courses to take first.
Most dental hygiene prerequisites are college science classes (anatomy and physiology, microbiology, chemistry) plus general education courses like English, psychology, sociology, speech, and math. According to ADEA (opens in a new tab), programs may require up to 40 credit hours of prerequisite college coursework before you start the hygiene program itself.
The exact list varies by program. Two schools in the same city can ask for different chemistry classes, different minimum grades, and different deadlines. Use this guide to learn the common pattern, then check every program on your list before you register for a class.
The usual dental hygiene prerequisites list
Here is the pattern you'll see at most programs. Credits are typical semester values, not a rule. Your program's catalog is the final word.
| Course | Often (semester credits) | Notes |
|---|---|---|
| Anatomy and Physiology I | 4 (with lab) | Almost always required. Often has its own prerequisite, such as biology. |
| Anatomy and Physiology II | 4 (with lab) | Usually taken right after A&P I. Some schools offer one combined course. |
| Microbiology | 4 (with lab) | Common and important. Infection control builds on it. |
| Chemistry | 4 (with lab) | General, inorganic, or a combined organic and biochemistry course, depending on the program. |
| English composition | 3 | Nearly universal. Some programs also want a second writing or literature course. |
| General psychology | 3 | Common. Helps with patient communication. |
| Sociology | 3 | Common. Some programs accept another social science instead. |
| Speech or communication | 3 | Often required. Public speaking or interpersonal communication. |
| Math | 3 | Usually college algebra or statistics. Check which level counts. |
| Nutrition | 3 | Required by some programs; others teach it inside the hygiene curriculum. |
Some programs add biology, medical terminology, or a humanities elective. Others fold certain courses into the program instead of requiring them first. That's why the total ranges from a handful of classes to about a year of full-time college work. After prerequisites, the associate program itself averages about 2 years (ADEA (opens in a new tab)). See how to become a dental hygienist for the full timeline.
Science classes
The science prerequisites carry the most weight. They fill fastest, and programs look at these grades first.
- Anatomy and physiology (A&P): the structure and function of the body. Head and neck anatomy, pharmacology, and periodontology in the program all build on it.
- Microbiology: bacteria, viruses, and how disease spreads. It is the base for infection control and for understanding gum disease.
- Chemistry: the requirement varies most here. Read the course description carefully. An intro chemistry course for non-majors may not count at a program that expects general, organic, and biochemistry.
Science classes usually need a lab. An online lecture without a lab often won't count, so confirm the format before you enroll.
General education classes
Gen ed prerequisites are lighter, but they still count toward your application GPA. Common ones are English composition, general psychology, sociology, speech or communication, and a college-level math course. These are often the easiest classes to take online, in summer, or while you wait on a science seat.
If you plan to earn an associate or bachelor's degree, check whether the same courses also satisfy the degree's general education requirements. Picking the right version once saves you from taking two sociology classes later. Our guide to choosing a dental hygiene program covers associate vs bachelor's options.
GPA and grades
Grades matter as much as the list itself. Programs set their own rules, but these patterns are common:
- A minimum grade per course, often a C or better. A C-minus or a D usually means retaking the class.
- A minimum prerequisite or science GPA to apply. This is a floor, not a target. Competitive programs often admit students well above it.
- Points-based ranking, where A's earn more points than B's. In these programs, one grade can move you up or down the list.
- Retake rules. Some programs average all attempts; others count only the most recent or penalize repeats.
Because rules differ, don't assume a school's minimum is enough. Ask each program what GPA its recent admitted class had, and how it treats repeated courses.
Entrance exams: HESI A2 and TEAS
Some programs require an entrance exam; many don't. The two you'll see most are the HESI Admission Assessment (A2) and the ATI TEAS. Both test reading, math, science, and English, and some programs score specific sections only.
- Check which exam each program accepts, the minimum score, and how recent the score must be.
- Find out how many attempts are allowed and whether the program counts your highest or most recent score.
- Take the exam after A&P if you can. The science section is easier with it fresh.
Course recency limits
Some programs require science prerequisites to be taken within a set number of years. The limit varies, and some programs have none. If you took A&P years ago, ask before you apply. Retaking an old course can also help if your first grade was low.
High school classes that help
High school classes usually don't replace college prerequisites, but they make them easier. If you are still in high school, take:
- Biology and chemistry, plus anatomy or health science if your school offers it.
- Algebra, so college math isn't a hurdle.
- English and a speech or communication class.
- Dual-enrollment college courses, if available. College credits like English composition or psychology may transfer. Confirm with the programs you're considering.
For the big picture after high school, see how to become a dental hygienist.
What to take first: an order of operations
A plan keeps you from waiting a semester on a class that fills fast or has its own prerequisite. A common sequence:
| Step | What to do | Why |
|---|---|---|
| 1. Before you register | Pick 2 to 4 target programs and write down each one's exact list, grade rules, and deadline. | You'll take courses that count everywhere, not just at one school. |
| 2. First term | Biology or chemistry (whichever A&P requires), English composition, and a math course. | These are often required before A&P, and they cover common gen eds. |
| 3. Second term | A&P I plus psychology or sociology. | A&P is the core. Pair it with a lighter class. |
| 4. Third term | A&P II and microbiology (if you can handle both), plus speech. | Finishes the heaviest sciences. |
| 5. Final stretch | Remaining gen eds and any nutrition requirement. Take the HESI or TEAS if needed. | Your science grades are in and fresh for the exam. |
| 6. Apply | Submit before each deadline with transcripts and scores. | Some programs let you apply with a class in progress. Ask. |
Taking fewer classes and earning A's often beats rushing and earning C's, especially at points-based programs.
Check each program's requirements
Every list above is a pattern, not a promise. Before you enroll in any class, confirm it with each program's catalog or advisor. Start with the programs in your area in the dental hygiene schools directory, then compare them side by side.
Keep track of it in one place: the BrushNotes prerequisite tracker tracks the typical prerequisite courses, your grades, and your prereq GPA, and shows what's still left to take.
Once you're in, the work changes. Read how to survive dental hygiene school before your first term.
Frequently asked questions
What classes do you need for dental hygiene?
Most programs require anatomy and physiology I and II, microbiology, and chemistry, all usually with labs. They also ask for general education courses such as English composition, psychology, sociology, speech, and college math. Some add nutrition or biology. The exact list varies by program, so check each one.
How many prerequisites are there?
It varies widely, from a handful of classes to about a year of full-time college work. ADEA (opens in a new tab) says programs may require up to 40 credit hours of prerequisite coursework.
What GPA do you need for dental hygiene school?
Each program sets its own minimum, and many look closely at your science GPA. The minimum is a floor, not a target. Competitive programs often admit students well above it, so ask each program about its recent admitted class.
Can I take prerequisites online?
Often, yes, for general education classes like English, psychology, and sociology. Science classes are trickier because many programs require an in-person lab. Confirm with each program before you enroll in an online science course.
Do prerequisites expire?
At some programs, yes. Some programs require science prerequisites to be taken within a set number of years. The limit varies, and some programs have none. Ask each program if your science classes are more than a few years old.
What high school classes should I take?
Biology, chemistry, algebra, and English help the most, plus anatomy or health science if offered. Dual-enrollment college courses can count toward prerequisites at some programs. Confirm transfer credit with the schools you're considering.
Is the TEAS or HESI required?
Only at some programs. Those that require an entrance exam usually ask for the HESI A2 or the ATI TEAS, each with its own minimum score, attempt limit, and score age rule. Check each program's admissions page.