改良骨膜抑制（MPI）技术与常规不翻瓣即刻种植方案在即刻种植中对牙槽骨尺寸变化疗效的对比评估

Participants receive immediately inserted implant via flapless approach with the grafting of cortico-cancellous bone allograft in the gap distance between dental implant and surrounding native alveolar bone followed by insertion of customized healing abutment.

Implant site preparation will be performed flapless using 3D computer assisted planned surgical stent. Implant site preparation will be performed using commercially available standard surgical kit. A single customized screw-type healing abutment will be screwed to the implant. Cortico-cancellous bone allograft will be inserted inside the extraction socket in the gap distance between the implant and surrounding alveolar bone of the fresh extraction socket.

Participants receive immediately inserted implant in conjunction with modified periosteal inhibition technique (MPI) after flap reflection from the buccal side and fixation of a 0.5 mm-thick cortical lamina glued to the buccal cortex with cyanoacrylate material. Collagen sponge will be filled in the gap distance followed by insertion of customized healing abutment.

After papillae incisions, an intra-sulcular incision will be made on the vestibular side of the extraction socket, extending to the mesial and distal mid-tooth with a #15c surgical scalpel. Implant site preparation will be performed using 3D computer assisted planned surgical stent. Implant site preparation will be performed using a standard surgical kit. A single customized screw-type healing abutment will be screwed to the implant. A full-thickness flap will be elevated creating a room that would allow the insertion of the cortical lamina. Cortical Lamina (0.5 mm thick) will be left in saline solution for 5 minutes and then cut to the desired shape, ranging from 8 to 10 mm in height, extending up to the mesial and distal margins of the extraction socket, molded until perfect fit and glued with two or three drops of N-butyl cyanoacrylate. A collagen sponge will be inserted inside the extraction socket to stabilize the clot. Suturing the papillae using 5-0 polypropylene monofilament.

Participants receive immediately inserted implant in conjunction with MPI technique as described in group 2, however, cortico-cancellous bone allograft will be placed in the gap distance instead of collagen sponge and followed by insertion of customized healing abutment.

After papillae incisions, an intra-sulcular incision will be made on the vestibular side of the extraction socket, extending to the mesial and distal mid-tooth with a #15c surgical scalpel. Implant site preparation will be performed using 3D computer assisted planned surgical stent. Implant site preparation will be performed using a standard surgical kit. A single customized screw-type healing abutment will be screwed to the implant. A full-thickness flap will be elevated creating a room that would allow the insertion of the cortical lamina. Cortical Lamina (0.5 mm thick) will be left in saline solution for 5 minutes and then cut to the desired shape, ranging from 8 to 10 mm in height, extending up to the mesial and distal margins of the extraction socket, molded until perfect fit and glued with two or three drops of N-butyl cyanoacrylate. cortico-cancellous bone allograft will be inserted in the gap distance. Suturing the papillae using 5-0 polypropylene monofilament.

1. Marginal Bone Level Measurements: It is the distance between a fixed reference point and the most apical point of connection between the implant surface and the bone. The reference point is the fixture-abutment interface.
2. Bucco-lingual Alveolar Width: Width measurements will be made on tomographic slices perpendicular to the longitudinal axis of the alveolar crest at 1, 3 and 6 mm from summit of the alveolar crest.

It will be evaluated using the Visual Analogue Scale (VAS), ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores represent worse outcomes.

score 1 indicates uneventful healing with no gingival edema, erythema suppuration, patient discomfort or flap dehiscence. Score 2 indicates uneventful healing with slight gingival edema, erythema, patient discomfort or flap dehiscence, but no suppuration. While score 3 indicates poor wound healing with significant gingival edema, erythema, patient discomfort, flap dehiscence, or any suppuration.

The stability of the implant will be evaluated with resonance frequency analysis (RFA). The measurements will be made with the Osstell device by connecting the transducer (smart peg) to the fixture. The mesiodistal and buccolingual direction will be measured and the mean implant stability quotient will be determined.

Using a calibrated plastic periodontal probe, the distance between marginal border of the gingiva and the tip of the probe will be measured in mm.

Esthetic scoring index called pink esthetic score (PES) index will be used in the current study. Seven variables will be scored; mesial papilla, distal papilla, curvature of the facial mucosa, level of the facial mucosa, alveolar process deficiency, soft tissue color, and texture of facial gingiva at the implant site. Each variable will be assessed with a 2-1-0 score, with 2 being the best and 0 being the poorest score. The mesial and distal papilla will be evaluated for completeness, incompleteness or absence. All other variables will be assessed by comparison with a reference tooth. The highest possible score reflecting a perfect match of the peri-implant soft tissue with that of the reference tooth will be 14. The PES index fulfilled important characteristics as inclusion of the peri-implant soft tissue and the restoration-inherent parameters.