Clinical context and challenges of periodontal regeneration

The treatment of infra-bony defects in patients with stage III or IV periodontitis (grades B/C) represents a major surgical challenge in terms of tissue stability. While enamel matrix derivatives (EMD) are established as the documented biological standard, platelet-rich fibrin (PRF) has emerged as a promising autologous alternative. For the practitioner, the choice between a manufactured biological agent and an autologous platelet concentrate depends on the ability of these materials to maintain consistent clinical results over time.

Study objective and hypotheses

This prospective and randomized clinical study (NCT07183631) aims to compare the long-term clinical results (3 years) of PRF compared to EMD in the treatment of periodontal intrabony defects. The study evaluates whether PRF can constitute a reliable alternative to EMD by measuring the clinical attachment level (CAL) gain as the primary endpoint. The hypothesis tested is based on the comparability of the two modalities in terms of pocket depth (PPD) reduction and gingival recession (GR) evolution, in order to determine if the autologous nature of PRF influences marginal tissue stability compared to enamel matrix derivatives.

Study methodology: PRF vs EMD over the long term

This prospective randomized clinical trial included 30 patients with Stage III/IV, Grade B/C periodontitis. The objective was to compare the long-term clinical efficacy of two regenerative approaches for the treatment of intrabony defects.

Inclusion criteria for surgical sites were strict: each patient had to present at least one intrabony defect with a probing pocket depth (PPD) ≥ 6 mm and an intrabony component ≥ 4 mm.

The protocol divided the defects into two experimental groups:

• Test Group (PRF): Regenerative surgery using platelet-rich fibrin, an autologous alternative.
• Control Group (EMD): Surgery using enamel matrix derivatives, the gold standard biological agent.

Clinical parameters were recorded at baseline, at 6 months and at 3 years postoperatively. Out of the 30 initial patients, 26 completed the full 3-year follow-up. The primary analysis focused on clinical attachment level (CAL) gain, while PPD reduction, gingival recession (GR) and bone sounding (BS) constituted the secondary criteria. Statistical validity was ensured by parametric and non-parametric tests with a significance threshold set at α = 0.05.

3-year clinical stability: PRF vs EMD

Of the 30 patients initially included (Stage III/IV periodontitis), 26 completed the 3-year follow-up. The study demonstrates that both approaches achieve significant and stable clinical improvements, with no major statistical difference between autologous (PRF) and enamel matrix derivative (EMD) for the majority of parameters.

The analysis of the results highlights several key points for daily practice:

• Clinical Attachment Level (CAL): Although the PRF group shows numerically superior values (3.77 mm versus 2.54 mm at 3 years), the difference between the two groups is not statistically significant.
• Gingival recession (GR): This is where PRF stands out. At 6 months, the increase in recession was already lower in the PRF group (0.53 mm vs 1.40 mm; p = 0.079). At 3 years, this difference becomes statistically significant: the PRF group shows stability, or even a slight improvement (-0.08 ± 0.64 mm), while the EMD group presents a more marked residual recession (0.77 ± 1.30 mm; p = 0.046).
• Bone sounding (BS): No significant inter-group difference was detected regarding the reduction in bone sounding.

Notable fact: the results obtained at 6 months are maintained over the long term. PRF thus confirms its role as a reliable autologous alternative, with a potential advantage in preserving the marginal gingival level compared to EMD in the treatment of infra-bony defects.

Analysis of clinical performance at 3 years

The data from this randomized clinical trial confirm that PRF is not only a promising alternative, but a biological agent whose long-term efficacy is comparable to that of EMD, the historical reference in the treatment of intrabony defects. Clinically, the stability of the results at 3 years — with a CAL gain of 3.77 mm for PRF compared to 2.54 mm for EMD — underlines the viability of the autologous approach. A major point of differentiation emerges: soft tissue management. The PRF group showed superior gingival stability, with significantly lower recession at 3 years (-0.08 mm vs 0.77 mm for EMD, p=0.046), a valuable clinical advantage for periodontal longevity and aesthetics.

Limits and nuances

The study, however, presents methodological limitations to consider. Although randomized and prospective, the final sample size remains modest (n=26). Furthermore, the retrospective registration of the clinical trial and the absence of statistically significant differences for pocket depth reduction (PPD) or CAL gain between the two groups suggest that, while PRF is effective, it does not supplant EMD in terms of pure regeneration, but equals it while being autologous.

Implications for practice

For the practitioner, these results validate PRF as a reliable and cost-effective therapeutic alternative for the treatment of deep periodontal defects (PPD ≥ 6 mm; infra-bony component ≥ 4 mm). While EMD is a standardized commercial product, PRF offers an autologous option without risk of immunogenic reaction, with comparable long-term efficacy and a potential benefit on post-operative gingival margin stability.

Summary of results

At 3 years, PRF and EMD show comparable and stable clinical performance for the treatment of intrabony defects, with respective CAL gains of 3.77 mm and 2.54 mm. PRF is distinguished by better soft tissue preservation, presenting significantly less gingival recession than EMD (-0.08 mm versus 0.77 mm; p=0.046).

In concrete terms, for the practitioner:

• High-performance autologous alternative: Use PRF as a reliable and cost-effective substitute for EMD; results on pocket reduction and attachment gain are clinically equivalent in the long term.
• Priority for aesthetic areas: Prioritize PRF in patients with a thin periodontium or high aesthetic requirements, as its ability to limit post-operative recession at 3 years is superior.
• Easier maintenance: Rely on the tissue stability offered by PRF, which guarantees better maintenance of the gingival margins compared to enamel matrix derivatives.

Technical lexicon of the study

Platelet-rich fibrin (PRF): Autologous second-generation platelet concentrate used in this study as a biological alternative for regenerative periodontology surgery.

Enamel matrix derivative (EMD): Enamel matrix derivative acting as the reference biological agent (control) to stimulate the regeneration of the tooth's supporting tissues.

Intrabony defects: Periodontal lesions characterized by bone loss where the base is located apically to the alveolar crest. The study included defects with an intrabony component ≥ 4 mm.

Clinical attachment level (CAL): Clinical attachment level measured from the cemento-enamel junction. It constitutes the primary outcome to evaluate the success of regeneration in this protocol.

Probing pocket depth (PPD): Probing pocket depth, corresponding to the distance between the marginal gingival margin and the base of the periodontal pocket (secondary evaluation criterion).

Gingival recession (GR): Gingival recession measuring the retreat of the gingival margin. The study compares the evolution of GR between the PRF and EMD groups, noting a significant difference in favor of PRF at 3 years.

Bone sounding (BS): Trans-gingival bone sounding performed under anesthesia to clinically evaluate the position and remodeling of the postoperative bone crest.

Information intended for healthcare professionals. This content may contain errors or truncated summaries. We recommend always verifying with the original source article. Delynov disclaims any responsibility regarding the use of this information. This document is not intended for patients or the general public.