The adjunctive use of platelet concentrates in the therapy of gingival recessions: a systematic review and meta-analysis

Clinical Efficacy of Concentrated Growth Factors for the Management of Marginal Tissue Recession: A Systematic Review and Meta-Analysis

INTRODUCTION

To systematically review existing scientific literature to determine, compare, and evaluate whether concentrated growth factors (CGF) or connective tissue grafts (CTG) is a better treatment alternative for patients with marginal tissue recession (MTR).

METHODS

Electronic databases like PubMed, Embase, Scopus, and Google Scholar were screened from the last 20 years reporting treatment of MTR using CGF or CTG and other techniques. Periodontal parameters like probing depth, clinical attachment level, recession depth, recession width, keratinized tissue width, root coverage, increase in gingival thickness and plaque index, and gingival index were compared. Standardized mean difference was used as a summary statistic measure with a random effect model and P value <0.05 as statistically significant.

RESULTS

Six studies fulfilled eligibility criteria and were included in qualitative synthesis, of which only 4 studies were suitable for meta-analysis. The pooled estimate through standardized mean difference signifies that CGF was superior to CTG in the reduction of probing depth, gingival index, and plaque index and gain in clinical attachment level while CTG was superior in reducing the recession depth and recession width. Both the procedures had an overall equal effect on keratinized tissue width and root coverage, but these differences were statistically insignificant ( P >0.05). Publication bias through the funnel plot showed symmetric distribution without systematic heterogeneity.

CONCLUSION

The present study suggests that treatment of MTR with CTG or CGF resulted in clinically favorable outcomes, but no statistically significant differences was observed between these 2 procedures regarding the outcome.

Autologous Platelet Concentrate of 2nd and 3rd generations efficacy in the surgical treatment of gingival recession: an overview of systematic reviews

BACKGROUND

Autologous platelet concentrate (APC)/platelet-rich fibrin (PRF) of second and third generations has increased use in periodontics to optimize wound healing. Few systematic reviews (SRs) have reported improved clinical outcomes, while other studies reported significantly better results for the connective tissue graft (CTG). There is still unclear clinical evidence about APC/PRF use to treat gingival recession (GR) defects. Then, the purpose of this SR was to evaluate the use of APC/PRF membranes (2nd and 3rd generations) in root coverage (RC) procedures and assess its efficacy as a substitute biomaterial.

MATERIALS AND METHODS

An electronic search was conducted in PubMed, Cochrane Central, Web of Science, Google Scholar, BookSC databases, and gray literature. The search strategy, without date restriction up to April 2020, included keywords as "platelet-rich fibrin," "autologous platelet concentrates," "blood," "systematic review," "periodontics," "surgery," "tissue," "gingiva," "gingival recession," "connective tissue," "graft," and "root coverage." The methodological quality was evaluated through the AMSTAR2, and a population, index test, comparator, outcome strategy was used to assess specific clinical parameters such as recession depth, clinical attachment levels, and RC outcomes.

RESULTS

Nine SRs were included. Only three articles described the technique of APC/PRF production. Three studies reported unfavorable outcomes using APC, while six reported favorable results and postoperative discomfort reduction. Articles included in this SRs that provided information about APC/PRF membranes (n = 13) showed no significant difference between APC/PRF and the control group for the parameters analyzed.

CONCLUSIONS

This implies that APC/PRF may be considered a feasible substitute biomaterial for treating GR defects, although the CTG still provides superior outcomes. Further long-term and controlled studies are needed to verify this finding.

Concentrated growth factor regulates the macrophage-mediated immune response

Concentrated growth factor (CGF) is a promising regenerative material that serves as a scaffold and adjunct growth factor for tissue engineering. The host immune response, particularly macrophage activity, plays a critical role in injury repair and tissue regeneration. However, the biological effect of CGF on the immune response is not clear. To enrich the theoretical groundwork for clinical application, the present study examined the immunoregulatory role of CGF in macrophage functional activities in vitro. The CGF scaffold appeared as a dense fibrin network with multiple embedded leukocytes and platelets, and it was biocompatible with macrophages. Concentrated bioactive factors in the CGF extract enhanced THP-1 monocyte recruitment and promoted the maturation of suspended monocytes into adherent macrophages. CGF extract also promoted THP-1 macrophage polarization toward the M2 phenotype with upregulated CD163 expression, as detected by cell morphology and surface marker expression. A cytokine antibody array showed that CGF extract exerted a regulatory effect on macrophage functional activities by reducing secretion of the inflammatory factor interleukin-1β while inducing expression of the chemokine regulated on activation, normal T cell expressed and secreted. Mechanistically, the AKT signaling pathway was activated, and an AKT inhibitor partially suppressed the immunomodulatory effect of CGF. Our findings reveal that CGF induces a favorable immune response mediated by macrophages, which represents a promising strategy for functional tissue regeneration.

Clinical evaluation of the treatment of multiple gingival recessions with connective tissue graft or concentrated growth factor using tunnel technique: a randomized controlled clinical trial

OBJECTIVE

To assess the effectiveness of the combination of tunnel technique (TT) and concentrated growth factor (CGF) for root coverage in treating multiple gingival recessions (GR) and compare with the connective tissue graft (CTG).

MATERIALS AND METHODS

Forty patients with Miller Class I and II maxillary or mandibular GR were randomly divided into two groups as follows: TT + CTG and TT + CGF. The results at baseline and 6 months were evaluated for the following clinical parameters: complete root coverage (CRC), mean root coverage (MRC), gingival thickness (GT), gingival recession width (RW), gingival recession depth (RD), and keratinized tissue width (KTW).

RESULTS

At 6 months, a statistically significant difference was found in RD, RW, MRC, CRC, KTW, and GT compared with the baseline (p < 0.05). MRC was determined 89.52±16.36% in the TT + CTG and 76.60±24.10% in the TT + CGF (p < 0.05). CRC was achieved in 66.7% of the TT + CTG and 47.4% of the TT + CGF (p < 0.05). The increase in KTW and GT was significantly better in the TT + CTG group compared to the TT + CGF (p < 0.05).

CONCLUSIONS

The study showed that TT + CGF did not improve the results as much as TT + CTG in the treatment of Miller Class I and II GR. However, this finding is not sufficient to advocate the true clinical effects of CGF on GR treatment with TT.

CLINICAL RELEVANCE

CGF could not serve as a direct alternative biomaterial to the gold standard CTG.

TRIAL REGISTRATION

ClinicalTrials.gov Identification Number: NCT04561947.

The Additional Effect of Autologous Platelet Concentrates to Coronally Advanced Flap in the Treatment of Gingival Recessions: A Systematic Review and Meta-Analysis

Background

To improve the efficacy of regenerative treatment for gingival recessions, the autologous platelet concentrates (APCs) combined with coronally advanced flap (CAF) have been investigated. However, few studies systematically assess the complementary effect of APCs in periodontal regeneration. The present study aims to evaluate the additional effect of different types of APCs to CAF in the treatment of gingival recessions.

Methods

Electronic databases (EMBASE, MEDLINE, and Cochrane Central Register of Controlled Trails) and relevant journals were searched until May 15, 2019. Only randomized controlled trials (RCTs) in English were included. Outcome variables include root coverage (RC), recession depth (RD), clinical attachment level (CAL), keratinized tissue width (KTW), and gingival thickness (GT). Data were analyzed with Revman5.3. The estimate of effect sizes was expressed as the mean differences and the 95% confidence interval.

Results

8 RCTs involving 170 patients (328 sites) were included. Our meta-analysis indicated RC, RD, CAL, KTW, and GT were better improved in the CAF plus APCs groups than the CAF alone. The subgroup analyses revealed that platelet-rich fibrin (PRF) brought significant improvement in RC, RD, CAL, and GT. Concentrated growth factors (CGF) lead clinic beneficial in CAL, KTW, and GT. No significant effect of platelet-rich plasma (PRP) could be found in any clinical parameters when combined with CAF.

Conclusions

PRF could exert additional effect to CAF; the preferred treatment for gingival recessions was considered. Based on the limited studies, it seemed that PRP failed to show any additional effect and it was not suggested for gingival recessions. Given the limited research and high risk of bias, it is still needed to confirm the additional effect of CGF by more high-quality studies.

Concentrated growth factor in the treatment of adjacent multiple gingival recessions: a split-mouth randomized clinical trial

AIM

The aim of this study was to determine the clinical effect of concentrated growth factor (CGF) in combination with coronally advanced flap (CAF) compared to CAF alone for the treatment of multiple adjacent gingival recessions (GRs).

MATERIALS AND METHODS

Twenty patients with a total of 119 Miller Class I and II GRs in the maxilla were included to this study. Recessions were randomly treated according to a split-mouth design by means of CAF + CGF (test; 60 defects) or CAF (control; 59 defects). Clinical outcomes were evaluated at baseline and 6 months after surgery.

RESULTS

The mean root coverage (MRC) was 82.06% and 86.67%, complete root coverage (CRC) was 45.8% (27/59) and 56.7% (34/60) for CAF and CAF + CGF, respectively at 6th month. Statistically no difference was demonstrated between the two groups in terms of recession depth (RD), MRC and CRC at 6th month. The increase in width of keratinized gingiva (KGW) and gingival thickness (GT) were statistically significant in the CAF + CGF group compared to the CAF group at 6th month.

CONCLUSIONS

The use of CGF in combination with CAF did not provide additional benefits in RD, CRC and MRC. This study suggests that use of CGF + CAF may increase the success of GRs because of a significant increase in KGW and GT.