Radiographic measurements of graft height change using a panoramic radiograph. Lower dotted line and upper dotted line mean implant platform and grafted sinus floor, respectively.a: The distance from the implant platform to the base of grafted sinus floor at the mesial side of the implant, b: The distance from the implant platform to the base of the grafted sinus floor at the middle side of the implant, c: The distance from the implant platform to the base of the grafted sinus floor at the distal side of the implant.