“…Three split-mouth design studies were performed [13], [14], [16]. Eight studies [1], [10], [13], [18], [21], [25]–[27] made use of surgical guides when inserting implants through the flapless surgical technique, five studies [12], [15], [17], [22], [24] used the surgical guides in both groups, whereas in ten studies [3]–[5], [11], [14], [16], [19], [20], [23], [28] the implants were inserted without any kind of surgical guide.…”