Dembele has missed the last five games after he aggravated an old hip injury while on international duty.
Villas-Boas admitted last week that he feared the 25-year-old would have to go under the knife to cure the problem which would have ruled him out for up to six weeks.
However, the midfielder could now return for the North London derby against Arsenal on Saturday week after a second scan confirmed surgery would not heal the problem.
The Spurs boss said: "We could either give him surgery immediately, but there is no certainty it will cure the problem, or he could rest, have manual therapy, train in the swimming pool.
"That allows the player the possibility of return within 10-15 days, so we are taking that option at the moment, without having the surgery."
Tottenham have won just one of the five games since the Belgian suffered his injury but Villas-Boas is confident he has the strength in depth to cope.
"We had good games without Mousa," said Villas-Boas. "Against Chelsea we lost Gareth Bale and Mousa and we gave them a run for their money even though they were on an amazing run.
"We had extremely good games against Southampton and Norwich. Good players are missed but this squad is full of good players.
"I don't think it has affected the tempo and dynamic - it's more important to have players fully concentrated and motivated."