This randomized clinical trial aims to evaluate the effect of microneedling with and without accelerated growth factor (AGF) injection on gingival tissue surrounding implant-supported fixed restorations. The peri-implant soft tissue phenotype is an important determinant of long-term implant stability and esthetic success. Patients with thin gingival biotype are more susceptible to mucosal recession, soft tissue transparency, and peri-implant complications. Enhancing gingival thickness and keratinized tissue width using minimally invasive methods can improve esthetic and biological outcomes.

Microneedling has recently been proposed as a simple and minimally invasive approach that stimulates local healing by inducing controlled micro-injury. It triggers angiogenesis and the release of intrinsic growth factors that promote soft tissue regeneration. Accelerated Growth Factor (AGF) is an autologous platelet concentrate obtained through a single-step centrifugation technique. It contains a high concentration of platelet-derived and vascular growth factors that enhance tissue repair and collagen synthesis. Combining microneedling with AGF may therefore produce synergistic effects, improving the soft tissue phenotype and peri-implant mucosal stability.

The study will include 20 participants aged 18-34 years with thin gingival biotype (0.8-1 mm) around maxillary anterior implants. Participants will be randomly assigned to one of two groups:

1. AGF group: AGF injection alone.
2. Microneedling + AGF group: Microneedling using sterile disposable lancets until pinpoint bleeding occurs, followed by AGF injection (0.2-0.3 mL per site).

Clinical parameters including gingival thickness (GT), keratinized tissue width (KTW), probing depth (PD), and bleeding index (BI) will be recorded at baseline, 3 months, and 6 months. All participants will receive standardized zirconia restorations following osseointegration. Statistical analysis will include intra- and inter-group comparisons, with significance set at p < 0.05.

The study is expected to clarify whether combining microneedling with AGF enhances peri-implant soft tissue thickness more effectively than AGF alone. If successful, this combined minimally invasive approach may offer a practical and biologically based technique to improve soft tissue health and esthetics around dental implants.

The peri-implant mucosa plays a crucial role in the biological and esthetic stability of dental implants. A thin gingival biotype is often associated with soft tissue recession, marginal bone loss, and esthetic compromise. Conventional augmentation techniques such as connective tissue grafting are effective but involve additional morbidity, donor site discomfort, and variable esthetic results. This study investigates a minimally invasive approach combining microneedling and accelerated growth factor (AGF) injection to enhance the gingival tissue phenotype around implant-supported restorations.

Microneedling is based on creating controlled micro-perforations in the soft tissue surface using fine needles. These micro-injuries induce a natural wound healing cascade that includes platelet activation, release of endogenous growth factors, angiogenesis, and fibroblast stimulation. The process enhances collagen deposition and epithelial thickening, which may increase the overall gingival thickness and keratinized tissue width.

AGF is an autologous blood-derived product obtained by a standardized single-step centrifugation technique that separates platelet-rich fractions containing high levels of biologically active molecules such as PDGF, VEGF, and TGF-β. These factors promote tissue regeneration and accelerate wound healing. Injecting AGF into peri-implant mucosa provides a reservoir of growth factors that stimulate fibroblast activity, improve tissue vascularity, and enhance collagen formation.

The hypothesis of this trial is that combining microneedling with AGF will yield superior soft tissue enhancement compared to AGF alone.

Study Design

This is a prospective, randomized, single-blinded, parallel-arm interventional clinical trial. 20 sites for patients aged 18-34 years with thin gingival biotype (0.8-1mm) in the maxillary anterior region will be included. Participants will be randomly assigned to two groups using a computer-generated random sequence:

1. AGF Group: AGF injection only.
2. Microneedling + AGF Group: Microneedling using sterile disposable lancets until pinpoint bleeding occurs, immediately followed by AGF injection (0.2-0.3 mL per site).

Methodology

The study follows five sequential phases:

1. Pre-surgical Phase: Clinical and radiographic evaluation, oral hygiene instructions, baseline measurement of GT, KTW, PD, and BI.

2. Surgical Phase: Implant placement in the maxillary anterior region followed by 3-4 months of osseointegration.

3. Intervention Phase: Randomized treatment application after healing.

4. Restorative Phase: Fabrication and cementation of standardized zirconia crowns.

5. Follow-up Phase: Assessment of all parameters at baseline, 3, and 6 months. Outcome Measures

   • Primary Outcome: Gingival thickness (GT) at baseline, 3, and 6 months.
   • Secondary Outcomes: Keratinized tissue width (KTW), probing depth (PD), and bleeding index (BI).

Statistical Analysis Data will be analyzed using SPSS software (IBM). Paired and unpaired t-tests will compare intra- and inter-group differences. The significance level will be set at p < 0.05.

Inclusion Criteria:

• Patients aged 18-34 years
• Thin gingival biotype ( 0.8- 1mm GT at maxillary anterior teeth)
• Non-smokers
• Plaque index (PI) score 0-1
• No bleeding on probing
• No malocclusion or crowding affecting implant site

Exclusion Criteria:

• Active orthodontic treatment
• Previous periodontal surgery at study sites
• Systemic diseases affecting healing
• Use of anticoagulants or drugs causing gingival enlargement
• Mucogingival stress or bruxism