Sindhu, the reigning world champion, defeated Denmark's Line Christophersen, ranked 24th in the world 21-19 21-9 on Thursday.
Sindhu looked sluggish in her first event in two months at last week's Denmark Open, where she lost in the quarterfinals to fast-rising Korean An Seyoung.
Sindhu, a bronze medalist at the Tokyo Olympics, took a break due to the hectic schedule during the Games, but she will be eager to win.
Loh Kean Yew defeated Lakshya Sen, who was the tournament's top seed and world no. 25, in 36 minutes to win his sixth international title.
In a three-game thriller, Ashwini Ponnappa and N Sikki Reddy lost to local favourites Freja Ravn and Amalie Magelund in the women’s doubles final.
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