This clinical trial is designed to evaluate and compare the performance of two soft
tissue augmentation techniques-autogenous subepithelial connective tissue graft (CTG) and
xenogeneic collagen matrix (XCM, Mucoderm®)-when used concurrently with dental implant
placement in the aesthetic zone of the anterior maxilla. The rationale for this study
stems from the clinical challenge of achieving optimal soft tissue esthetics and function
following tooth loss. While CTG has long been considered the gold standard for increasing
peri-implant soft tissue thickness, it requires a secondary surgical site, which may lead
to donor site morbidity, limited tissue availability, and increased surgical time. In
contrast, XCM offers a promising alternative that is biocompatible, readily available,
and less invasive.
Patients aged 18 years or older with a single missing tooth in the aesthetic zone,
adequate bucco-palatal bone (≥6 mm), and at least 5 mm of keratinized tissue width will
be considered eligible for the study. The enrollment process begins with a thorough
screening process involving clinical and radiographic examinations, including a low-dose,
small-field CBCT scan and an intraoral scan. These imaging modalities allow for accurate
digital implant planning using specialized software, ensuring optimal implant
positioning. The digital data will be used to fabricate a stereolithographic surgical
guide and design a custom CAD/CAM screw-retained provisional restoration.
Following successful screening and informed consent, the surgical phase commences. Under
local anesthesia, a full-thickness flap is elevated at the implant site. Guided by the
digital plan, a dental implant is precisely positioned using the surgical guide. At this
point, participants are allocated to one of two intervention groups based on a strict
randomization protocol.
In the CTG group, a connective tissue graft is harvested from the palatal mucosa using
the de- epithelialized free gingival graft technique. The harvested graft is then trimmed
to match the dimensions of the recipient site and carefully positioned under the elevated
flap to augment the soft tissue. The donor site is sutured using gelatin matrix to ensure
proper healing. This technique, while effective, is associated with postoperative
discomfort and additional surgical time due to the need for a second operative site.
Conversely, in the XCM group, soft tissue augmentation is achieved using a xenogeneic
collagen matrix (Mucoderm®). The graft, initially measuring 15 × 20 mm, is first
moistened in saline for 10 minutes and slightly compressed to adapt its thickness to the
defect. After a superficial incision to release any muscle tension, the XCM is accurately
positioned and secured to the buccal mucosa using single sutures. Following soft tissue
augmentation, a screw-retained provisional restoration is attached immediately,
contributing to both function and esthetics during the healing phase.
The primary outcome of the study is the increase in the buccal soft tissue profile,
quantitatively assessed using intraoral scans to generate digital surface models at three
critical time points: preoperatively (T0), immediately after surgery (T1), and 3 months
postoperatively (T2). Secondary outcomes include clinical assessments-such as probing
depth, plaque index, bleeding on probing, keratinized tissue width, graft dimensions,
wound closure, surgery time, and complications-as well as radiographic evaluation of
marginal bone loss. In addition, patient-reported outcome measures (PROMs), including
postoperative pain, swelling, aesthetic satisfaction, and willingness to undergo the same
treatment again, will be recorded using validated visual analogue and Likert scales.
Aesthetic outcomes, including mid-facial recession, Pink aesthetic score, and mucosal
scarring index, will also be documented.
The data will be analyzed on an intention-to-treat basis by an independent statistician.
Statistical comparisons between the two groups will help determine whether the xenogeneic
collagen matrix offers comparable or superior results to the autogenous connective tissue
graft regarding soft tissue volume augmentation, esthetic outcomes, and patient
satisfaction. Ethical approval has been obtained from the University of Damascus, and the
trial follows the CONSORT guidelines. The results will be disseminated through
peer-reviewed publications and presentations at professional conferences, contributing
valuable evidence to the field of implant dentistry.
Overall, this study is expected to provide insight into whether XCM can serve as a
reliable, less invasive alternative to CTG, thereby potentially enhancing patient
outcomes and reducing the complications associated with donor site morbidity.