Comparative Evaluation of Vitamin C and Injectable Platelet-rich Fibrin in the Management of Thin Gingival Phenotype: A Split-mouth Randomized Clinical Trial.

2026-04-24
The journal of contemporary dental practice 27(2)
- Noha M Abdelhay
- Manar T Elzanaty
- Riham O Ibrahim

PubMed: 42145166
DOI: 10.5005/jp-journals-10024-4022

Study Design

Type: Randomized Controlled Trial (RCT)
Population: 16 systemically healthy participants (14 females, 2 males; 18-40 years) presenting with a thin gingival phenotype
Methods: Randomized, controlled, split-mouth clinical trial; one side received MN + vitamin C (intervention), contralateral side received MN + i-PRF (control); interventions performed in three sessions at 7-day intervals; clinical parameters recorded at baseline, 1, 3, and 6 months
Duration: 6 months
Funding: Unclear

Aim

To compare the clinical efficacy of injectable vitamin C and injectable platelet-rich fibrin (i-PRF), each combined with microneedling (MN), in enhancing gingival thickness (GT) among individuals with a thin gingival phenotype.

Materials and methods

This randomized, controlled, split-mouth clinical trial included 16 systemically healthy participants (14 females, 2 males; 18-40 years) presenting with a thin gingival phenotype. In each patient, one side received MN + vitamin C (intervention), and the contralateral side received MN + i-PRF (control). Interventions were performed in three sessions at 7-day intervals. Clinical parameters-GT, keratinized tissue width (KTW), pocket depth (PD), gingival index (GI), and plaque index (PI)-were recorded at baseline, 1, 3, and 6 months. Data were analyzed using two-way repeated measures ANOVA and mixed cumulative linked models (CLMs), with p < 0.05 considered significant.

Results

Both groups showed a statistically significant increase in GT over time (p < 0.001). The vitamin C group achieved significantly greater GT at 1 month (1.71 ± 0.29 vs 1.55 ± 0.35 mm; p = 0.007) and 3 months (1.39 ± 0.33 vs 1.26 ± 0.33 mm; p = 0.034), while differences were not significant at 6 months. Keratinized tissue width changes were minimal and comparable between groups. Pocket depth decreased slightly in both groups, with i-PRF showing a significantly lower PD at 6 months (p = 0.040). Both GI and PI improved significantly over time, with vitamin C showing a trend toward greater GI reduction (p = 0.053). No adverse effects were observed, and 92.3% of participants reported high satisfaction.

Conclusion

Injectable vitamin C combined with MN is a safe, minimally invasive, and effective approach for improving GT and esthetics in thin periodontal phenotypes, showing comparable long-term outcomes to i-PRF.

Clinical significance

Development of newer, less invasive therapeutic approaches that help in the prevention of gingival recession. A thin gingival biotype is more prone to gingival recession and to achieve satisfactory therapeutic results with minimum trauma to tissues of any interventional process. How to cite this article: Abdelhay NM, Elzanaty MT, Ibrahim RO. Comparative Evaluation of Vitamin C and Injectable Platelet-rich Fibrin in the Management of Thin Gingival Phenotype: A Split-mouth Randomized Clinical Trial. J Contemp Dent Pract 2026;27(2):170-178.

Research Insights

Vitamin C→Increased Gingival Thickness
The vitamin C group achieved significantly greater GT at 1 month (1.71 ± 0.29 vs 1.55 ± 0.35 mm; p = 0.007) and 3 months (1.39 ± 0.33 vs 1.26 ± 0.33 mm; p = 0.034)
Effect
Beneficial
Effect size
Moderate
Vitamin C→Increased Keratinized Tissue Width
Keratinized tissue width changes were minimal and comparable between groups.
Effect
Neutral
Effect size
Small
Vitamin C→Reduced Gingival Index
Both GI and PI improved significantly over time, with vitamin C showing a trend toward greater GI reduction (p = 0.053)
Effect
Beneficial
Effect size
Small
Vitamin C→Reduced Plaque Index
Both GI and PI improved significantly over time
Effect
Beneficial
Effect size
Small
Vitamin C→Reduced Pocket Depth
Pocket depth decreased slightly in both groups, with i-PRF showing a significantly lower PD at 6 months (p = 0.040)
Effect
Neutral
Effect size
Small

Adverse Events Reported

Vitamin C→Overall tolerability
No adverse effects were observed, and 92.3% of participants reported high satisfaction.
Finding
Reported