Buccal Soft Tissue Contour Changes After Immediate Implant Placement with or Without Connective Tissue Graft

Volumetric Evaluation of Buccal Soft Tissue Contour Using Customized Healing Abutment During Immediate Implant Placement with Connective Tissue Grafting. a Randomized Controlled Clinical Trial

Statement of the problem: Using customized contoured healing abutments at the time of immediate implant placement is a treatment modality to improve esthetics by maintain the soft tissue contour. Using connective tissue grafts enhances and maintains soft tissue stability. However, the effect of the combined procedures for maintenance of the soft tissue morphology remains unclear. Purpose : The aim of the study is to evaluate the volumetric difference of buccal soft tissue contour around immediate implants placed with and without connective tissue grafts and customized healing abutments. Materials and Methods: Fifty-two patients with single maxillary anterior or premolar tooth indicated for extraction will participate in this study, 13 patients will randomly be assigned in each group. Group 1 (test group) will be treated by immediate implant placement (IIP) with connective tissue graft (CTG) and customized healing abutment, Group 2 (test group) IIP with CTG and healing abutment same diameter of the implant, Group 3 (test group) IIP and customized healing abutment, while the 4th group (control) IIP with healing abutment same diameter of the implant. Extra-oral scanning of the buccal contour will be carried out presurgical and at 3, 6, 9 and 12 months after surgery. Difference in contour gained will be compared to the original contour and between groups. Radiographic evaluation will be done using CBCT at 12 months to measure the bone width. In addition, soft tissue thickness, mid facial recession, gingival biotype, interdental papilla height, soft tissue peri- implant parameters and any surgical or prosthetic complications will be assessed.

After administration of local anaesthesia, the tooth will be extracted by the principle investigator without raising flaps, as atraumatically as possible by using periotomes without disturbing the papillary tissues (minimal traumatic extraction technique). After the extraction of the tooth, the socket will be carefully cleaned to excavate the granulation tissue in the marginal and apical regions. Using standard implant system protocol preparation of the osteotomy will take place. Initial drill will be placed palatally till final drill reached. Placement of the implant without any raising of the flap will be performed in the correct implant position. Primary stability of the implant will be measured by rotational insertion torque value, to be ≥30Ncm (31). After implant placement, the allocation will be revealed to the practitioner for the type of the healing abutment to be used and whether connective tissue graft will be used or not.

Thirteen implants (intervention 1) will receive screw- retained customized healing abutment, and thirteen other implants in the 2nd intervention group will receive the conventional healing abutment of same diameter of the implant. In both groups connective tissue graft will be used. Connective tissue grafts will be harvested from the hard palate and placed at the implant sites in a supraperiosteal partial dissection (pouch technique) prepared at the buccal aspect without using vertical incisions and without flap elevation. Sutures will be used to stabilize the graft in its desired place.

The fabrication of the customized healing abutment is as follows; the temporary cylindrical abutment will be screwed to the implant then flowable composite will be injected at the gingival margin level to adapt to the screw-retained temporary cylindrical abutments that will be sand-blasted for mechanical retention of the composite, taking the shape of the socket at the marginal gingiva. A buccal groove will be made after the polymerization of this material for easier application. The abutments will be removed for final configurations of the apical part mimicking the emergence profile of the extracted tooth and finishing with laboratory discs and burs. The custom healing screw will then be screwed to the implant with the correct torque. Patients will be recalled for regular follow ups. Other thirteen implants (intervention 3) will receive screw- retained customized healing abutment, and for the control (the 4th group) group thirteen implants will receive the conventional healing abutment of same diameter of the implant. No connective tissue grafts are to be used in these two groups.

Inclusion Criteria:

1. Adults at or above the age of 18.
2. Patients who have at least one non-restorable maxillary anterior or premolar tooth with sound adjacent teeth.
3. Intact thick biotype gingival tissue with at least 2mm band of keratinized tissue.
4. Buccal bone thickness should be 1mm or less assessed in CBCT with good apical bone.
5. Sagittal root position type 1 as described by Kan et al(24).
6. Good oral hygiene
7. Patient accepts to provide an informed consent

Exclusion Criteria:

1. Smokers
2. Pregnant and lactating females.
3. Medically compromised patients, as Uncontrolled diabetic patients, patients taking bisphosphonates injection for treatment of osteoporosis, patients with active cardiac diseases, patients undergoing radiotherapy or chemotherapy, or any other medical and general contraindications for the surgical procedure (i.e. ASA score ≥III) (25)
4. Patients with active infection related at the site of implant/bone graft placement.
5. Patients with untreated active periodontal diseases.
6. Patients with parafunctional habits.