Kirk: Mr. Spock, have you accounted for the variable mass of whales and water in your time re-entry program?
Spock: Mr. Scott cannot give me exact figures, Admiral, so... I will make a guess.
Kirk: A guess? You, Spock? That's extraordinary.
Spock: [to Dr. McCoy] I don't think he understands.
McCoy: No, Spock. He means that he feels safer about your guesses than most other people's facts.
Spock: Then you're saying... It is a compliment?
McCoy: It is.
Spock: Ah. Then, I will try to make the best guess I can.
McCoy: Please do.
Spock: Your use of language has altered since our arrival. It is currently laced with, shall we say, more colorful metaphors, "double dumb-ass on you" and so forth.
Kirk: Oh, you mean the profanity?
Spock: Yes.
Kirk: Well that's simply the way they talk here. Nobody pays any attention to you unless you swear every other word.
Spock: Forgive me doctor. I'm recieving a number of distress calls.
McCoy: I don't doubt it!
Answer: The lock, and the area around it, would have become hot as a result of melting the lock. The hospital staff would then jump to the conclusion that the lock was melted. The real reason they mention it, however, is so the audience knows what he did to the lock.
But you would think, if the doorknob was still searing hot two seconds after being fused, that the first thing out of the surgeon's mouth would be a scream of pain, rather than "He melted the lock!"
Charles Austin Miller