**4.2 Donor site preparation**

The palatal masticatory mucosa is the most used donor site for FGG harvesting. Usually, the donor site is located inside the premolar and molar areas. The anterior palatal region where rugae are present is usually avoided since the rugae will remain present inside the FGG and will be transplanted to the recipient site, further deteriorating the appearance of the grafted site. The presence of the rugae can render the harvesting of the FGG challenging, especially in situations where the thin (1.0–1.5 mm) FGG grafts are harvested.

The harvesting procedure can be done freehand or with the help of a template.

The design of the flap consists of four incisions outlining the graft—coronal horizontal incision, mesial and distal vertical incision, and apical horizontal incision. Usually, the goal is to harvest an FGG which thickness is not exceeding 1.5 mm. For depth orientation during the performance of the outlining incision of the future graft, only the beveled part of the blade can be used which dimensions are approximately 1 mm [25, 44].

During healing, FGG undergoes contraction of around 30% of initially gain keratinized tissue band [7, 40, 93]. This fact should be taken into consideration while determining the dimension of the graft, which should be 30% larger than the site needing augmentation (**Figures 19–22**) [40].

#### **Figure 19.**

*Figureloss of vestibular depth and coronal and palatal displacement of keratinized mucosa after guided bone regeneration.*

#### **Figure 20.**

*Apically positioned flap-the recipient site has been prepared with the apical displacement of a split-thickness buccal flap. The exposed periosteal surface is present in the recipient site.*

*Peri-Implant Soft Tissue Augmentation DOI: http://dx.doi.org/10.5772/intechopen.101336*

#### **Figure 22.**

*Final three-unit screw-retained bridge. On the buccal side a wide zone of KM and deepen vestibule is present.*

After completion of graft dissection, the wound in the donor site is protected. Different techniques have been proposed—sutures, absorbable gelatin sponge, cyanoacrylate bioadhesive, periodontal dressing, palatal stents, platelet-rich fibrin, or a combination of some of the aforementioned techniques (**Figures 23–34**) [25, 26, 48, 53, 94, 95].

**Figure 23.** *Two months after implant insertion in the region 36. Visible loss of keratinized mucosa-lateral view.*

#### **Figure 25.**

*Recipient site preparation—Apically positioned flap was prepared in the recipient region. The partial-thickness flap was stabilized in the new apical position using resorbable sutures. The height of the recipient site was measured.*

#### **Figure 26.**

*Recipient site preparation—Apically positioned flap was prepared in the recipient region. The partial-thickness flap was stabilized in the new apical position using resorbable sutures. The width of the recipient site was measured.*

#### **Figure 27.**

*Initial incisions outlining the future FGG—The dimensions of the graft were determined based on the measurements of the recipient site. The donor site was located in the region of the first molar, posterior to the rugae area. To avoid exercise bleeding during FGG preparation, the last outlining incision (horizontal apical incision) was done at the end of the procedure.*

#### **Figure 28.**

*1–1.5 mm thick flap was prepared, starting from the coronal horizontal incision extending apically until reaching the imaginary line connecting the apical end of the two vertical incisions. The preparation of the FGG was terminated with the horizontal apical incision which completely dissected the FGG from the rest of the palatal soft tissue.*

**Figure 29.** *FGG after harvesting.*

**Figure 31.** *Dimensions of the harvested FGG.*

#### **Figure 32.**

*Thickness of the harvested FGG—The thickness of the graft should not exceed 1.5 mm in order to reduce the postoperative morbidity associated with the donor site.*

#### **Figure 33.**

*Initial stabilization of the FGG in the recipient site—The stabilization of the graft is initiated by applying simple interrupted sutures on the coronal part of the graft. Afterward, one to two additional simple interrupted sutures are applied on the mesial and distal vertical border of the flap- stretching the flap over the exposed periosteal surface in the donor area. In order to stabilize the graft, the needle must engage the graft and the periosteal surface.*

#### **Figure 34.**

*Final graft stabilization—Mattress crossed sutures extending from the coronal to the apical part of the recipient site are used to secure even contact throughout the inner surface of the graft and the periosteal surface.*
