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

Evaluation of platelet derived growth factor-BB levels in injectable platelet rich fibrin coated graft using gingival pedicle split thickness tunnel technique for isolated gingival recession: A randomized controlled trial

Background

Use of injectable-platelet rich fibrin (i-PRF) in the field of periodontal regeneration is quite well known due to its efficacy. The study was aimed to evaluate the platelet derived growth factor-BB (PDGF-BB) levels in cases of isolated gingival recession using gingival pedicle split thickness tunnel technique (GPST) and de-epithelialized gingival graft (DGG) with or without coating it with i-PRF.

Methodology

20 patients exhibiting Miller's class I/II isolated gingival recession were selected for this parallel arm randomized controlled trial. Recipient site was prepared using GPST technique, free gingival graft was harvested and de-epithelialized, further graft was coated with i-PRF and wound fluid samples from surgical site were collected at baseline, 3rd day and 7th day for group A. The same procedure without coating the graft in i-PRF was carried out for group B. Clinical parameters like probing depth, recession depth, recession width, width of keratinized gingiva, wound healing index (WHI), complete root coverage was recorded at baseline and after 4 months.

Results

Significant intergroup difference was seen in WHI and the levels of PDGF-BB from baseline to the last estimated time point (p < 0.05).

Conclusion

The study emphasizes on the use of novel GPST technique in conjunction with DGG coated with liquid PRF, which has shown sustained release of PDGF-BB resulting in better wound healing.

Mixed-Thickness Tunnel Access (MiTT) through a Linear Vertical Mucosal Incision for a Minimally Invasive Approach for Root Coverage Procedures in Anterior and Posterior Sites: Technical Description and Case Series with 1-Year Follow-Up

PURPOSE

The goal of this article was to introduce a new root coverage (RC) technique, the mixed-thickness tunnel access (MiTT) technique, which approaches a full-split design and intends to augment soft tissues coronal to the gingival margin. It was shown step-by-step, and the results were presented in a case series.

METHODS

Healthy individuals (non-diabetics) and non-smokers with gingival recession (GR) type 1 or 2 (RT1 or RT2) were included. After evaluation, prophylaxis was performed 14 days before the surgical procedure. During the surgical appointment, one or two vertical incision(s) on the mucosa (around 1-2 mm apical to the MGJ), lateral to the papilla base, was/were performed after anesthesia. Initially, there was a partial incision to detach the mucosa of the muscles (split design). It was permitted (but not mandatory) to perform intrasulcular incisions. Through the vertical incision, internally, subperiosteal access from the MGJ toward the gingival margin (coronally) was performed to create a full-thickness tunnel. Then, communication from the vertical incision with the gingival sulcus and the papilla base occurred, keeping the papilla tip intact. A connective tissue graft was harvested and inserted through the linear incision or intrasulcularly. There were interrupted sutures. An adjunctive material may be applied (e.g., Endogain). The root coverage was measured using a periodontal probe and considered fully covered when the gingival margin was 1 mm coronal to the cementum-enamel junction (CEJ).

RESULTS

Nine healthy individuals (seven females and two males) aged 19 and 43 were enrolled. They were treated following the MiTT steps. Four cases had a single GR; two patients had two teeth involved; and three others had three or four GR. There were seven cases of RT1 and two RT2. All RT1 cases achieved 100% RC, while the mean RC obtained for RT2 was around 80%.

CONCLUSION

The MiTT technique can be considered a more straightforward approach for minimally invasive surgical techniques, which is a feasible option to treat RC with a high success rate, predictability, and esthetic preservation. Therefore, there is a technical sensitivity to performing the full-split design procedure.

Effectiveness of Plasma-Rich Fibrin and De-Epithelialized Free Gingival Graft in the Treatment of Gingival Recessions

Introduction/Aim: Soft tissue dehiscences such as gingival recessions are a very common problem that we face in modern periodontics. This clinical study aimed to analyze the effectiveness of surgical procedures using a de-epithelialized gingival graft (DGG) combined with a coronally advanced flap and to evaluate the application of plasma-rich fibrin (PRF). Methods: The study included 40 teeth (20 patients) with Miller class I and II gingival recessions. Twenty recessions (20 patients) were treated utilizing the de-epithelialized gingival graft in combination with the coronally advanced flap, and on the opposite side of the jaw, the same number of recessions were treated utilizing plasma-rich fibrin combined with the coronally advanced flap. To evaluate tissue condition and the clinical parameters before and after the surgical procedure, the following parameters were used: the degree of epithelial attachment (DEA), the width of keratinized gingiva (WKG), and the vertical depth of recession (VDR). Results: based on the achieved results and the analysis of clinical parameters, a statistically significant reduction in the vertical depth of recession was proven in both groups, with very similar mean percentages of root coverage, with the difference being that the stability of the soft tissues of the treated region was more visible in the DGG. Conclusion: using modern surgical procedures allows the regeneration of not only the soft tissues but also deeper periodontal tissues.

Analysis of the effects of concentrated growth factor and low-level laser therapy on the bone healing

Purpose

The aim of this study is to evaluate whether concentrated growth factor (CGF) and photobiomodulation (PBMT) can show synergistic effect on bone healing process.

Methods

In vivo osteogenesis studies were performed in a rabbit critical-sized calvarial defect model. Four 8 mm critical-sized bone defects were created on each rabbit calvarium, and these 4 defects were randomly divided into 4 groups: 1-control (defect filled with autologous blood clot); 2-CGF (defect filled with CGF); 3-LLLT (defect filled with autologous blood clot and received Nd:YAG low-level laser irradiation); 4-CGF + LLLT (defect filled with CGF and received LLLT). 15 Japanese big-ear white rabbits were operated on using the same procedure in this study. Then, 5 rabbits were selected randomly and sacrificed at 4th, 6th and 8th week postoperatively and respectively. The calvariums were harvested and scanned by micro-CT. The volumes of new bone formation of these defects were calculated by analyzing the micro-CT image. Data were analyzed as mean values of each group, comparisons were made for statistical analysis with the group and among the 4 groups using analysis of variance (ANOVA, P < 0.05).

Results

At the 4th, 6th and 8th weeks, compared with the control group, the volume of new bone formed in each experimental group was significantly increased. Both CGF and LLLT can accelerate bone healing, but the effect of LLLT is better than that of CGF, and the difference between the two is statistically significant (P < 0.01). There was no statistically significant difference in the osteogenic effect between the combined application of CGF + LLLT and the application of CGF alone. And the osteogenic effect of the former two groups was weaker than that obtained by laser irradiation alone.

Conclusions

Both CGF and LLLT can promote osteogenesis effectively, but the combination of the two did not show a synergistic effect. The pro-osteogenic effect of Nd:YAG low-level laser irradiation is superior to that of CGF, and also superior to the combined effect of the two.

Tensile Strength Essay Comparing Three Different Platelet-Rich Fibrin Membranes (L-PRF, A-PRF, and A-PRF+): A Mechanical and Structural In Vitro Evaluation

Predictable outcomes intended by the application of PRF (platelet-rich fibrin) derivative membranes have created a lack of consideration for their consistency and functional integrity. This study aimed to compare the mechanical properties through tensile strength and analyze the structural organization among the membranes produced by L-PRF (leukocyte platelet-rich fibrin), A-PRF (advanced platelet-rich fibrin), and A-PRF+ (advanced platelet-rich fibrin plus) (original protocols) that varied in centrifugation speed and time. L-PRF (n = 12), A-PRF (n = 19), and A-PRF+ (n = 13) membranes were submitted to a traction test, evaluating the maximum and average traction. For maximum traction, 0.0020, 0.0022, and 0.0010 N·mm−2 were obtained for A-PRF, A-PRF+, and L-PRF, respectively; regarding the average resistance to traction, 0.0012, 0.0015, and 0.006 N·mm−2 were obtained, respectively (A-PRF+ > A-PRF > L-PRF). For all groups studied, significant results were found. In the surface morphology observations through SEM, the L-PRF matrix showed a highly compact surface with thick fibers present within interfibrous areas with the apparent destruction of red blood cells and leukocytes. The A-PRF protocol showed a dense matrix composed of thin and elongated fibers that seemed to follow a preferential and orientated direction in which the platelets were well-adhered. Porosity was also evident with a large diameter of the interfibrous spaces whereas A-PRF+ was the most porous platelet concentrate with the greatest fiber abundance and cell preservation. Thus, this study concluded that A-PRF+ produced membranes with significant and higher maximum traction results, indicating a better viscoelastic strength when stretched by two opposing forces.