PMC7306078_01
(a) Preoperative occlusal view; (b) orthopantomography; (c) preoperative periapical radiograph.
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The intraoral exam revealed a nonrestorable carious lesion in the upper right first premolar (Figure 1(a)), confirmed with orthopantomography (Figure 1(b)) and periapical radiograph performed with Rinn holder (Figure 1(c)), in which a periapical periodontitis was highlighted.
(a) L-PRF clots placed on a plate; (b) L-PRF membranes; (c) postextractive socket; (d) socket grafted with L-PRF membranes; (e) suture; (f) suture removal; (g) 14 days after tooth extraction; (h) 28 days after tooth extraction; (i) 60 days after tooth extraction.
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L-PRF clots were collected from each tube and separated from the red thrombus (composed of red cells), obtaining a fibrin clot with a small red portion in order to include the intermediate portion rich in leucocytes and platelets. L-PRF clots were then placed in a sterile box and slightly compressed for about 5 minutes under a stainless steel plate to form 4 membranes (Figures 2(a) and 2(b)). Atraumatic extraction was performed using a piezoelectric device (Piezosurgery , Mectron, Genova, Italy) to preserve the buccal bone and avoid soft tissue laceration, followed by alveolar debridement and irrigation with sterile saline solution (Figure 2(c)). The socket was then filled with three L-PRF membranes previously folded and condensed with a sterile gauze (Figure 2(d)). Soft tissues were sutured (4/0 nylon suture, 20 mm needle) at the mesial, median, and distal aspects of the socket, without primary closure (Figure 2(e)).
Histological specimen of the bone tissue taken at the center of the grafted site showing bone tissue surrounded by connective tissue matrix. Hematoxylin-eosin staining; (a) original magnification x5; (b) surgical trephine bur with bone tissue sample.
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After 3 months, before implant placement, a bone biopsy was performed with a surgical trephine bur (2.0 mm internal diameter) at the center of the ridge for histomorphometric analysis of the grafted site (Figures 3(a) and 3(b)) according to Corsi et al..
(a) Implant site preparation; (b) implant placement; (c) suture; (d) periapical radiograph after implant placement; (e) soft tissue conditioning; (f) screw-retained zirconia crown; (g) follow-up 6 months after final restoration.
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After bone biopsy (Figure 4(a)), a 3.7 x 10 mm implant (Intra-Lock , Boca Raton, Florida, USA) was placed (Figure 4(b)) and soft tissues sutured (4/0 nylon suture, 20 mm needle) with primary closure (Figure 4(c)). A periapical radiograph was also performed at this time to check correct implant placement (Figure 4(d)). Sutures were then removed 7 days after implant surgery, and a healing abutment was positioned during the second surgery two months later to obtain soft tissue conditioning (Figure 4(e)). A silicone impression with individual tray was taken one month later to fabricate a screw-retained zirconia crown (Figure 4(f)).