Locum Tenens Coverage: Your Hygiene Hole Costs More Than You Think

Two open hygiene appointments a day, the kind that look like rounding errors on a slow Tuesday, drain more than $66,000 a year out of a practice at an average $165 per visit, according to Dentistry Today. A hygienist who gives notice in March and isn't replaced until June costs a multiple of that, and most owners spend those twelve weeks haggling with a temp agency over a $20 hourly difference.

Our view: locum hygiene coverage is not emergency spend. It's a standing line item, and any practice running one or two hygiene columns should be paying to keep two credentialed temps warm before anyone resigns. Plenty of owners will disagree, because a $78-an-hour agency temp looks obscene next to a W-2 hygienist at $47. That comparison is the single most expensive mistake in dental staffing, and here is the number that should settle it: you could pay a temp $153 an hour and still be ahead of a dark chair.

Hygiene Isn't a Department, It's a Quarter of the Practice

The reason a hygiene hole hurts out of proportion to its payroll line is that hygiene carries far more of the practice than its cost suggests. Hygiene Mastery puts a well-run hygiene department at 23 to 35 percent of total practice production, and prices two openings per day at roughly $60,000 annually in lost production at $150 per visit. Dentistry Today runs the same arithmetic at $165 and lands above $66,000.

Both of those figures describe leakage, not closure. They assume a hygienist is in the building and two slots went unfilled. A resignation is a different category of problem: the whole column goes dark, and with it the restorative diagnosis that column feeds the doctor's schedule. If hygiene is a quarter to a third of production, losing a hygiene column for a quarter of the year isn't a staffing inconvenience. It's a contraction of the business.

Owners feel this late because the P&L flatters them at first. Payroll drops the day the hygienist leaves. Production drops over the following six weeks as the recall book empties. The two don't show up in the same month, so the first statement after a resignation often looks fine, which is exactly when the wrong decision gets made.

The Break-Even Temp Rate Is $153 an Hour

Run the real scenario. One hygiene column, four days a week, eight patients a day at $165 per visit. That column produces $1,320 a day.

Supplies, sterilization and instrument turnover on eight prophy visits run about $12 a visit, call it $96 a day, so the column's contribution before labor is $1,224.

Spread $1,224 across an eight-hour day and the break-even labor rate for that chair is $153 an hour.

Now the comparison owners actually make. The Bureau of Labor Statistics reports a median annual wage of $98,100 for dental hygienists in 2025, which is $47.16 an hour across a 2,080-hour year.

Load that with payroll taxes, workers' comp and benefits at 25 percent and your W-2 hygienist costs about $59 an hour.

An agency temp at $78 an hour costs $624 for the day, with no benefits, no PTO accrual and no unemployment tail.

Daily contribution with the temp in the chair: $1,320 of production, less $96 of supplies, less $624 of labor, equals $600.

Twelve weeks at four days a week is 48 days. Covered, that column contributes $28,800. Dark, it contributes zero while rent, the equipment note, the front desk and your hygiene coordinator all keep getting paid.

And the gross production you walked away from over those twelve weeks is $63,360, which is why the published $60,000 to $66,000 figures for two measly open slots should be read as a floor, not a ceiling.

The spread between $59 and $78 an hour, the one that stalls the decision for three weeks, is $152 a day.

You are protecting $152 and surrendering $600. We wouldn't take that trade on any day of the week, and we'd stop pretending the agency markup is the number worth negotiating hardest.

The Restorative You Never Diagnosed

The $28,800 above counts only hygiene production. It ignores the fact that the hygiene chair is where most restorative gets found.

Model it conservatively. Say one in ten hygiene visits surfaces treatment the doctor schedules, at an average $400 of production. That's 0.8 cases a day at $400, or $320 a day of downstream work.

Across 48 dark days, that's $15,360 of restorative that never entered the schedule.

Add it to the covered-column contribution and the twelve-week decision is worth about $44,160 before you account for a single patient lost to attrition.

Those are our assumptions, not published figures, and your conversion rate and average case size will move them. Move them in either direction and the conclusion holds, because the comparison isn't temp rate versus staff rate. It's temp rate versus nothing.

What Most Owners Get Wrong: Benchmarking the Temp Against the W-2

The specific mistake is using your own hygienist's hourly cost as the reference price for coverage. It gets made most reliably by the owner we'd otherwise call the best operator in the building: the single-doctor or two-doctor owner who does their own bookkeeping, knows hygiene wages should land around a third of hygiene production, and has held that ratio for a decade. That discipline is exactly what fails here. A ratio built for a filled chair tells you nothing about an empty one.

The second mistake follows from the first. Because the temp rate reads as a penalty, owners only call when they're already bleeding. That means sourcing coverage in the same week as the resignation, with no credentialing on file, no software login provisioned, no fee schedule loaded, and no idea which temps in the market are competent. You end up taking whoever answers, in the week you can least afford a bad one, and then you conclude that temps don't work.

The third one is quieter: covering with the doctor. Blocking an hour of doctor time to scale a prophy converts a chair worth $1,224 a day into a chair worth $1,224 a day while idling a chair worth considerably more. It feels thrifty. It's the most expensive hygiene coverage available.

Cross-training an assistant into expanded hygiene functions is a legitimate play in some states and not in others, and the scope rules vary enough that it needs a direct read of your own practice act rather than a blog's summary. Treat it as a medium-term option, not as this month's answer.

The Recall Book Doesn't Just Pause, It Leaks

Here is the cost that never shows up in anybody's spreadsheet. When you cancel twelve weeks of hygiene, you don't reschedule twelve weeks of hygiene. Some share of those patients move to the practice that answered the phone with an opening. Some simply drop out of the recall cycle and reappear in eighteen months with more disease and less loyalty.

Assume a six-month recall and 48 appointments displaced per dark month. Even a 10 percent permanent attrition rate on a twelve-week closure means you've handed roughly 19 active patients to the market, each worth their annual hygiene plus whatever restorative follows.

That's the part the temp invoice is actually buying: not scaling, but continuity of the recall system that makes the practice worth something at sale. A hygiene column that goes dark for a quarter shows up in a valuation two years later as a flat active-patient count.

The Shortage Isn't a Cycle, So Stop Budgeting Like It Is

Owners keep treating hygiene coverage as a bad year to get through. The workforce data says otherwise. The ADA Health Policy Institute reports that only 60 percent of dentists have an adequate number of hygienists on staff, and that 91 percent of dentists who recently recruited one called it very or extremely challenging. That is not a tight quarter. That's four in ten practices operating short, and nearly every recruiter struggling.

The demand side compounds it. The Bureau of Labor Statistics counts about 225,300 hygienist jobs and projects 8 percent employment growth from 2025 to 2035, much faster than the average occupation. More seats to fill, against a hiring process nine in ten dentists already find punishing.

In that market, the agency premium isn't gouging. It's the clearing price for flexible labor in a structural shortage, and it will go up, not down. Budget it as a permanent line, the way you budget lab fees. We'd put a standing rate agreement with two agencies or two independent temps in place this quarter, keep both credentialed and logged into your software, and accept paying a small amount for nothing most months. The option has value even when it isn't used.

How We'd Set the Bench Up

Three things make temp coverage work rather than confirm your suspicion that it doesn't. First, pre-credentialing: license verification, HIPAA and OSHA acknowledgment, practice-management login, and a signed rate letter, all done before there's a vacancy. Second, schedule triage: block temps into straightforward adult prophy and move active perio, anxious patients and complex medical histories to your retained hygienist or the doctor. A temp's productivity problem is almost always a scheduling problem. Third, a one-page operatory sheet: where the ultrasonic tips live, how perio charting is entered, what the recall interval defaults are, who approves radiographs.

Build that once and a resignation becomes a 48-hour inconvenience instead of a twelve-week contraction. Skip it and you'll be sourcing labor in the worst week of your year, which is the condition under which temps genuinely do underperform.

What Would Change Our Mind

Two things. If agency rates in a given market climb past roughly $140 an hour, the break-even argument narrows enough that a four-day hygiene week with denser scheduling starts to beat partial coverage, and we'd want to see that math per market rather than nationally. And if teledentistry-supported hygiene assessment or wider expanded-function scope changes what a non-hygienist can legally produce in that chair, the whole cost structure moves. We're tracking agency rate sheets and state scope changes through the rest of the year, and we'll publish the break-even table when we have enough markets to compare.

Do This Before Friday

Pull your hygiene production per visit and per day from the last 90 days, then divide daily contribution by eight to get your own break-even hourly rate. Call two temp agencies and one independent hygienist and get written rates on file, whether or not you need anyone right now. Provision a spare software login and write the one-page operatory sheet while your current hygienist is still around to dictate it. Then set a rule in writing: hygiene days get covered, not canceled, up to your break-even rate.

If you want to see what a dark hygiene column does to your overhead percentage rather than just your production, plug your hygiene payroll, supply cost and daily production into our overhead calculator and run your own numbers. It takes a few minutes, and it will tell you the exact hourly rate at which coverage stops paying in your practice, which is a far more useful number than the one the agency quotes you.