The long-term efficacy of adequate keratinized mucosa (>2 mm) in dental implants is controversial. Peri-implant plastic surgeries are currently used because they increase keratinized mucosa width (KMW), helping to regain peri-implant health and maintaining it over the long-term. We present the clinical findings using free-gingival-graft (FGG) and free-periosteal-graft (FPG) techniques in peri-implant plastic surgery for implant rehabilitation patients. We included 20 patients with implant indications of inadequate KMW (KMW < 2 mm for postimplantation) in the maxilla and mandible. All underwent clinical and radiographic measurements and a treatment protocol was prepared for implant rehabilitation and subsequent peri-implant plastic surgery. A decision as to whether and when FGG or FPG techniques would be used was made. FGG/FPG was performed pre-implantation (before monocortical block-bone augmentation) or postimplantation (before/during/after stage 2 surgery). KMW was ≥ 2 mm after application of FGG/FPG pre- or post-implantation. Moreover, peri-implant tissue health was regained/maintained in all cases from 6 months to 4 years. Peri-implant plastic surgery techniques can prevent hard- and soft-tissue problems after implant rehabilitation and during treatment of developing problems. However, surgical design and timing, and an interdisciplinary perspective determine the success of peri-implant plastic surgery.