The Turin giants won 2-0 at AC Milan to move 11 points clear of Roma at the top of the standings with 12 games remaining.
"These are three very important points," Buffon said to Gazzetta dello Sport. "However, we have to be very careful.
"It's not over yet and Roma are a very strong side who are not competing in Europe, which is an important factor."
Roma, who have a game in hand, were held to a goalless draw at home to Inter Milan on Saturday.
"The important thing is that if we were to struggle in the future, then we can hopefully make the most of this advantage," Buffon said.
The result in Milan was Juve's 22nd league win of the campaign.
The Turin giants have lost just one league game all season while they boast the strongest attack in the competition and have the second best defensive line, behind Roma.
"When you go to the San Siro to face Milan, there is never a favourite," Buffon said. "Neither side wants to lose.
"This is the first time we have won here under coach Antonio Conte.
"We have to give a lot of credit to the team because we did well under pressure.
"It is also very important that for a fourth consecutive game we didn't concede a goal.
"I have the best defenders and also our strikers are giving them a hand, it's all about team play."
Juve host Fiorentina next while Roma face another major hurdle when they travel to the San Paolo stadium to face third-place Napoli this weekend.