Soft Tissue Changes Around Dental Implants

This study will characterize, for the first time, the healing pattern of soft tissues around dental implants in case of soft tissue augmentation and in comparison, to normal healing.

An innovative and comprehensive geometric/thermal imaging analysis will be employed that is non-contact and non-invasive to patients and will allow to characterize the healing process in a 2D-3D dimensional and volumetric way.

This approach, combined with LSCI and clinical and radiographic outcomes, will provide new data on the biology and critical phases of soft tissue healing around implants, as well as on the stability and aesthetics of the peri-implant tissues with different grafts.

Patient-reported outcome measurements (PROMs) will also be used to assess the level of pain and discomfort associated with soft tissue augmentation procedures.

Inclusion criteria

• Age between 20 and 80 years.
• Good medical and psychological health.
• Absence of untreated caries lesions and untreated/uncontrolled periodontal disease. If patients require periodontal treatment (non-surgical and/or surgical), this has to be arranged outside the study protocol and completed at least 30 days prior to the enrolment.
• Need of a single-tooth replacement in the aesthetic (incisor, canine or premolar) region.
• Presence of adequate bone for implant placement without need for significant bone regeneration. In particular, the patients should have a bucco-palatal residual alveolar width of at least 6 mm at the central and crestal aspect of the single tooth gap to ensure complete embedding of an implant by bone (De Bruyckere et al., 2018).
• A residual alveolar height >8 mm, enough inter-arch space for a crown and a minimum distance of 6 mm from the adjacent teeth.
• The width and height will be confirmed after x-ray examination in Visit 1 (or extra visit). Cases of small apical fenestration (≤ 25% of implant length) after implant placement will not be excluded, but will be treated according to the GBR principle (collagen membrane associated with a deproteinized bovine bone graft) to re-establish the bone contour and without over contouring.
• At least 8 weeks of post-extraction socket healing had occurred in the edentulous site.
• Willingness to sign the informed consent form.

Exclusion criteria

• Self-reported pregnancy and lactation.
• Any known systemic disease affecting bone metabolism (e.g. Cushing's syndrome, crohn's disease, rheumatoid arthritis, osteoporosis, diabetes type I and uncontrolled diabetes type II), systemic infections or recent surgical procedures within 30 days of study initiation.
• Chronic treatment (i.e., 2 weeks or more) with any medication known to affect oral status (e.g., phenytoin, dihydropyridine, calcium antagonists and cyclosporine) or bone metabolism (e.g. bisphosphonates, hormone replacement therapy, immunosuppressants) within 1 month before baseline visit.
• HIV or viral hepatitis.
• Physical handicaps that would interfere with the ability to perform adequate oral hygiene.
• Self-reported alcoholism or chronic drug abuse.
• Heavy smokers (>10/cigarettes per day).
• Patients suffering from a known psychological disorder or with limited mental capacity or language skills such that study information could not be understood, informed consent could be obtained or simple instructions could be followed.
• Full-mouth bleeding (BOP) and plaque (PI) scores >30% or sites with periodontal pocket depth >5 mm at the completion of the pre-treatment phase.
• Very thin or very thick biotypes that according to the clinician's judgement would either risk to have complications or would not benefit from receiving a graft.
• <2 mm KT buccally (from the mucogingival junction to the coronal aspect of the crestal soft tissue).