Peter pondered his options. Ann had trusted him to help with her temporary filling, even though he didn't have any dental training. So, he should trust Ann to replace his filling as well. At least she had some training, and he didn't want to let her down.

"Are you sure you can do it?" Peter asked.

"I have done it before, it's not a big deal," she said confidently.

"Ok, let's do it."

"Great! I'll use amalgam for the new filling, if it's ok for you. It will last longer, and it's easier for me to use."

"Sure, I guess you know that better. At least it suits you."

"Thanks for the compliment!"

Ann laughed and tilted her head back so that Peter caught a good glimpse of her upper silver fillings and the brand new snow white temporary filling. He liked the view, and it made him to feel a bit more confident; Ann must know from her own experience how it feels for a dental patient.

She put her face mask on, took the drill, and held it in front of Peter's face, like to let him anticipate what was going to happen next. He felt butterflies in his stomach.

"I'll just use the drill to remove the old filling, so it shouldn't be painful. You don't need numbing or anything," she said.

Peter was not quite convinced, but he didn't want to resist, so he nodded affirmatively. The turn of events was overwhelming to him. He had gone to the student party, with the idea of drinking a couple of beers and maybe making some new friends, but somehow he ended up laying on a dental chair to face the drill, one of his worst nightmares. His whole body was taken over by a sensation that was a strange combination of anxiety and excitement. He felt his penis was getting harder, which he hoped Ann wouldn't notice.

The high-pitched whirring sound of the drill filled the air as Ann started to carve the broken filling with the drill. She seemed to be confident in what she was doing: her drilling hand was steady, and she also used the suction with her other hand. Due to the bright dental light, the water droplets and filling debris spraying out of his mouth were clearly visible to Peter. He didn't feel any pain, just the vibration, and he gradually began to relax.

Then, after a good while of drilling, he suddenly felt an intense burst of sharp pain and moaned. Ann stopped the drill and started scraping the bottom of the hole with an explorer.

"Oh, it looks like there is some active decay beneath the old filling. It means that I need to drill deeper than I thought," she said.

She changed to a low-speed drill and started drilling. He felt pain again, but this time the pain was dull and not as intense as the pain he felt with the high-speed drill. He could feel the pressure and movement of the drill as it moved around inside his molar. She drilled for a while, then scraped the hole with the explorer, continued drilling, and scraped again.

"Unfortunately, it looks like the decay goes all the way to the nerve. The only way to save the tooth is to do a root canal. I'm really sorry for that," Ann said empathetically.

Peter's heart almost stopped. Root canal, the most frightening words in dentistry. He tried to stay calm. He had quite a few fillings, but he hadn't had a root canal done before.

"Are you qualified to do that?" he asked.

"Well, I know how to do it. I never did it for a real patient though, just for a dummy."

I didn't sound very convincing for Peter, but he understood that it would be awkward for both him and Ann to find a root canal specialist in this situation. Maybe Ann would be kicked out of the dental school, if someone found out she's treating patients without supervision.

"If you want to do it, I need at least some numbing. I'm feeling pain already," Peter said.

"Yes, I know that. Actually, I know something better. I can give you some gas."

Ann went to the storage room beside the office, and came back shortly, pushing a trolley with a heavy gas cylinder.

"Are you sure that is medical gas, and not gas for welding?" Peter asked, looking horrified.

"Don't be silly, I have seen my dad using this many times."

Ann took a medical gas mask and a hose from one of the drawers in the office. Then she carefully connected one end of the hose in the gas cylinder, and the other end to the mask. Finally, she put the mask on Peter's face.

"Just relax and take a deep breath," Ann said convincingly.

She opened the valve of the gas cylinder, and Peter heard a puffing sound as the gas started flowing. He breathed in slowly and the room began to turn around at an increasing speed. He saw that Ann was saying something, but he couldn't hear her voice anymore. His eyes were heavy, and the world around him faded away.