…Remineralization? What's That?
Pssshiiiing—! The terrifying sound that kept people from easily crossing the threshold of a dental clinic. At first glance, it resembled the whine of a steel-cutting drill from a construction site—the unmistakable noise from the handpiece.
No need to scare him any more. Not even the right timing to use the handpiece, either.
The handpiece was primarily used for grinding down teeth, with a structure inside that sprayed both water and air. When activated, it spun at 30,000 to 50,000 RPM, so to cool the intense heat generated by the air turbine, it released water along with a burst of air.
It's a device that clearly shows what happens if you mess around without needing any verbal explanation—you could end up dead.
Pssshiiiiooong—!
"Levi? We're about to start the real cavity treatment now. If you keep making noises or moving, I really can't predict what might happen."
"Euhhheuhh."
"Stop."
After hearing my kind explanation, Levi blinked his moistening eyes in response while seated in the unit chair. The handpiece's dynamic roar had tamed the acrobat Levi into a docile patient.
I stopped the handpiece and gave Levi a gentle smile.
"First, if the pain becomes too hard to bear. Second, if your throat fills with water and you can't breathe. Third, if your jaw hurts from keeping your mouth open so long. Other than that, if it's too tough, just raise your left hand a little, and it'll make the treatment comfortable for both of us. If you understand, just blink."
His eyes blinked vigorously like strobe lights in a club, confirming he'd gotten the message.
"Director! I'm here. Sorry I'm late—Hazel and I had to reschedule patients."
Since I'd slotted in this unscheduled dental treatment, Hazel and Stella had been running around busy.
"Stella, remember practicing cavity treatments in the VR operating room? Today's the real deal."
"Yes, Director."
Stella and the other witches had practiced various surgeries every day after work in the 8th-floor VR operating room. And today, it was Stella's turn to assist me—not as a nurse, but as a dental hygienist.
I turned back to Levi.
"Lastly, dental treatments use tools that spray water and air. Our hygienist will announce when the water and air come out, so don't be startled."
Blink blink blink—
"It's clean water, but foreign matter builds up during treatment, so try not to swallow it. Alright, shall we begin? Ah—"
"Ah~"
The moment Levi opened his mouth, Stella wrinkled her nose.
"Did this patient eat shit before coming here?"
"Stella, mind your words in front of the patient. He just hasn't brushed his teeth, that's all."
"Ugh... water."
Blink blink blink blink—
Before the main treatment, we began thoroughly cleaning every nook and cranny of Levi's teeth, which reeked to high heaven.
"Director, umssutong... uh, I mean, oral cleaning seems done?"
"...Suction."
Stella wasn't entirely wrong, but she desperately needed training in patient etiquette.
"Stella, dry him off."
"Air."
Despite her blunt speech, Stella handled the three-way syringe—the tool for water and air—and the suction with expert skill.
Witches really are something else.
After suction, when Stella blew air, the cavities hidden by saliva came into view. Using the pointed hook of the explorer, a dental probe, I started scraping the enamel—the tooth's surface layer. Unlike the smooth surrounding areas, it snagged with a tack-tack feel as the decayed bits flaked off.
Thirteen minor cavities just on the enamel. He probably hasn't eaten much sugary food, so for someone who doesn't brush, this is better than expected.
The cavities needing treatment could be finished with resin alone—no need for inlays, onlays, or crowns. I reclined the unit chair.
"Levi, out of your 16 cavities, luckily only three need immediate treatment. The rest should be fine if you brush properly. Now, I'm going to give you a local anesthetic injection—"
"W-Wait a minute! What does that mean?"
"...?"
Contrary to my expectation that he'd be thrilled about treating only three, Levi's face rotted like his cavities.
"Treating just three means pulling the other thirteen after they fully decay! Are you telling me to die?!"
"...Calm down."
Pushiiiioong—!
Reactivating the handpiece instantly quieted the thrashing Levi. It really hit me how knowing dental theory and facing a real patient were worlds apart.
"I told you brushing is important, right? Consistent brushing allows for remineralization of the teeth."
"...Remineralization? What's that?"
Remineralization was the natural process where teeth eroded by cavity acids restored and strengthened themselves. But explaining it that way wouldn't land.
"Just like wounded skin heals over time, if you brush thoroughly every nook and cranny every day, the cavities can recover on their own. It's not about letting them rot on purpose and then pulling them."
"Hahaha! No way! Remineralization! I never imagined—arglrglrk...!"
Stella, tired of listening, activated the three-way syringe.
"...Stella, don't act without instructions."
"Yes, Director."
Well, the point was it only applied if you brushed well, but Levi was already acting like his 13 cavities had vanished.
"It's not extraction like Clementine's, but treatment might cause sensitivity or pain, so we'll do the anesthetic injection."
"Ah, yes. The shot you mentioned on the way here that blocks the pain?"
"It only stings a bit when injecting, but if you move, we might have to extract for real—so you must endure it."
"Gasp! A-Absolutely... I'll endure no matter what."
Terrified, the injection went off without a hitch. Soon after, confirming anesthesia, I began removing the decay deep into the enamel.
Pssshiiiing—!
Healthy tooth structure must be preserved, targeting only decay—this required delicate work.
"Suction."
Thooooop—
If the decay had reached the dentin—the yellow layer beneath enamel—it would need an inlay, but thankfully it hadn't.
"Stella, cavity prep done—prepare etching."
"Yes."
After removing decay, a hole called the cavity preparation or "cavity" remained. Before filling with resin, prep work was essential. Resin doesn't bond well to teeth, so first came etching—acid erosion.
Etching cleaned the tooth surface and poured blue liquid into the cavity to create microscopic roughness for adhesion.
"Don't move."
Drip—
Ignoring Levi's frantic blinking like a pedestrian signal, I carefully etched. The blue liquid was acid; a splash on gums could cause chemical burns.
"Suction with metal grip."
"Spray."
"Air."
Following my cues, Stella suctioned the pooled blue acid, rinsed with spray, and dried thoroughly with air.
"Adhesive now."
I coated the cavity meticulously with bonding agent for resin adhesion, then dried it with air.
"Levi, close your eyes and don't open until I say. I'm using a light harmful to your eyes."
His blinking eyes shut; I activated the curing light.
Click—
The light-polymerization unit activated the adhesive with blue light.
Click—
Light off; now the main resin filling.
Using a syringe, I carefully layered flowable resin—liquid form—over the adhesive, spreading it evenly with the explorer hook.
"Keep eyes closed. More light coming."
Cure the flowable layer, then layer packable resin—rubber-dough texture—in increments, shaping and curing repeatedly.
"Director, question. Why not dump all the packable resin at once? Seems like unnecessary steps."
Stella asked curiously.
"Fair thought. But light-curing causes shrinkage. Dumping it all creates gaps, leading to failure. Layering in three or four stages minimizes that."
"Ah... Never thought of that."
"Ask away whenever curious—you need to learn. Now, polishing to finish."
"Yes."
Free treatment or not, polishing wasn't optional—it was essential. It made the resin shiny and smooth, reducing food trapping. Also adjusted height to match the original tooth.
"Good. One down. We'll speed through the other twelve."
"Yes."
Treatment time per tooth: 10-15 minutes, varying by condition. Given his umssutong-level state, three hours later, all thirteen resins were done.
"Levi, treatment complete. Open your eyes, rinse with water, then stand."
Levi spat into the cuspidor on the unit chair's left, blinking as he rose.
"No way... It's really over? No extractions?"
"Of course. People are waiting—head to the plaza?"
"Hahaha, great! Let's go!"
With the beaming, innocent country-boy smile, we returned to the plaza. Mounting the platform, Levi bellowed:
"This guy's a total con artist! It hurt like hell! Clementine's extractions are way better!"
"..."
His innocent gaze turned venomous as he spewed lies, and the crowd nodded knowingly, hurling curses at me.
"Oh, really? Fine then. Walter, hand it over."
But it didn't matter. I was already prepared for betrayal.