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

The Effect of Connective Tissue Graft Compared to Concentrated Growth Factor Graft on Buccal Peri-Implant Gingival Thickness: A 12-month Randomized Controlled Clinical Trial

BACKGROUND

Attached gingival phenotype has a crucial impact on the implant's durability and its future success.

PURPOSE

This study aims to measure and compare buccal peri-implant gingival thickness following grafting with connective tissue graft (CTG) and the concentrated growth factor (CGF) graft.

STUDY DESIGN, SETTING, SAMPLE

This is a split-mouth designed randomized controlled clinical study in which a total of 20 aged 18 to 55 have bilateral missing teeth in the maxillary premolar region with less than 2 mm of healthy peri-implant gingival thickness. Patients were excluded if they were smokers, had poor oral hygiene, had uncontrolled widespread periodontal disease, or had a history of radiation treatment. The same surgical protocol was followed for each study participant, where an independent blinded medical practitioner assigned the first stage side to be treated with CTG, while the second stage side with CGF 2 weeks later.

EXPOSURE VARIABLE

The primary exposure variable of this study was the gingival grafting technique; CTG or CGF.

OUTCOME VARIABLE

The primary outcome variable was the buccal peri-implant gingival thickness. Gingival thickness was measured at six different times; immediately before the procedure (T0), after 30 days (T1), after 45 days (T2), after 3 months (T3), after 6 months (T4), and after 12 months (T5).

COVARIATES

The covariates were age, sex general health, and periodontal status.

ANALYSIS

The statistical analysis; repeated measures analysis of variance test was used to compare the gingival thickness between the studied follow-up times within each group. The level of significance was set at ≤ 0.05.

RESULTS

The sample was composed of 40 treatment sites of 20 patients. The mean age of the sample was 32 years and 45% were male. The mean gingival thickness value of the CTG group was 1.62 mm with a (standard deviation = 0.18) compared to 1.28 mm for the CGF group with (standard deviation = 0.20) and an overall P value (0.001) at T5.

CONCLUSIONS AND RELEVANCE

CTG showed to have better gingival thickness than CGF in managing peri-implant buccal gingival thickness deficiency.

Efficacy of concentrated growth factor (CGF) in the surgical treatment of oral diseases: a systematic review and meta-analysis

BACKGROUND

Concentrated growth factor (CGF), a new autologous platelet concentrate, has been widely investigated to the adjunctive treatment of oral diseases. This study aims to evaluate the efficacy of CGF in the surgical treatment of oral diseases.

METHODS

MEDLINE, Web of Science, Scopus, Cochrane, and EMBASE databases were searched up to July 2023. Only randomized clinical trials were included. The methodologic quality was evaluated by the Cochrane Risk of Bias Tool. RevMan 5.4 software was used for data analysis.

RESULTS

In the treatment of periodontal intrabony defects, bone graft combined with CGF was significantly superior to bone graft (P < 0.01), with mean intrabony defect depth reduction of 1.41 mm and mean clinical attachment level gain of 0.55 mm. In the regenerative surgery of furcation defects, the effect of CGF group was significantly better than control group (P < 0.0001), with mean probing depth reduction of 0.99 mm, vertical bone gain of 0.25 mm, and horizontal bone gain of 0.34 mm. CGF combined with coronally advanced flap (CAF) was more effective than CAF alone (mean keratinized tissue width increase of 0.41 mm, mean gingival thickness increase of 0.26 mm, P < 0.00001), but less effective than connective tissue graft (CTG) combined with CAF (mean root coverage difference of -15.1%, mean gingival thickness difference of -0.5 mm, P < 0.0001). In the alveolar ridge preservation, additional use of CGF reduced horizontal bone resorption by 1.41 mm and buccal vertical bone resorption by 1.01 mm compared to control group (P < 0.0001). The VAS score of CGF group was significantly lower than that of the control group at the 1st and 7th day after oral surgery (P < 0.0001).

CONCLUSIONS

CGF can exert a positive adjunctive effect for the regenerative surgery of periodontal intrabony defects, furcation defects, and alveolar ridge preservation procedure. CGF combined with CAF has a better therapeutic effect on gingival recession compared to CAF alone, although it is not as effective as CTG combined with CAF. CGF could promote postoperative healing and pain relief in oral surgery within a week. There is currently not enough evidence to support the clinical benefits of CGF in other oral surgeries.

Clinical Efficacy of Platelet Derivatives in Periodontal Tissue Regeneration: An Umbrella Review

Objectives

This umbrella review aimed to consolidate the best available evidence regarding the clinical efficacy of platelet derivatives in the treatment of periodontal defects associated with periodontitis and in the management of mucogingival deformities.

Materials and Methods

The "umbrella review" strategy was used to identify systematic reviews and meta-analyses. The search was performed without language restrictions and updated at the end of February 2023. The PubMed and Scopus databases, together with gray literature, were included in the search.

Results

The search yielded 412 studies. Subsequently, 12 articles were selected for further examination based on relevance. Finally, eight systematic reviews and meta-analyses were assessed. Regarding intrabony defects, in terms of clinical attachment level (CAL) gain, platelet-rich fibrin (PRF) was observed to lead to a statistically significant attachment gain compared to surgical therapy alone. PRF was also found to show greater CAL gain compared to platelet-rich plasma (PRP) and other biomaterials. The parameter probing depth decreased significantly when PRF was used compared to surgical therapy alone (P < 0.05). Similar results were seen when leukocyte- and platelet-rich fibrin (L-PRF) was applied. In terms of radiographic bone fill, both PRF and PRP showed significantly greater bone fill compared to surgical therapy. Regarding the results of periodontal plastic surgery, PRF favored a slight root coverage compared to the coronally displaced flap. This result depended on the number of PRF and L-PRF membranes used, but Emdogain or connective tissue graft produced better results regardless. However, an improvement in the healing of periodontal tissues was reported.

Conclusions

Therapies with platelet derivatives applied to intrabony defects provided superior regenerative results compared to monotherapies, except in the case of root coverage.

Alveolar ridge preservation in post-extraction sockets using concentrated growth factors: a split-mouth, randomized, controlled clinical trial

Aim

The aim of this clinical trial was to assess the impact of autologous concentrated growth factor (CGF) as a socket-filling material and its ridge preservation properties following the lower third molar extraction.

Materials and methods

A total of 60 sides of 30 participants who had completely symmetrical bilateral impacted lower third molars were enrolled. The primary outcome variables of the study were bone height and width, bone density, and socket surface area in the coronal section. Cone beam computed tomography images were obtained immediately after surgery and three months after surgery as a temporal measure. Follow-up data were compared to the baseline using paired and unpaired t-tests.

Results

CGF sites had higher values in height and width when compared to control sites (Buccal wall 32.9 ± 3.5 vs 29.4 ± 4.3 mm, Lingual wall 25.4 ± 3.5 vs 23.1 ± 4 mm, and Alveolar bone width 21.07 ± 1.55vs19.53 ± 1.90 mm, respectively). Bone density showed significantly higher values in CGF sites than in control sites (Coronal half 200 ± 127.3 vs -84.1 ± 121.3 and Apical half 406.5 ± 103 vs 64.2 ± 158.6, respectively). There was a significant difference between both sites in the reduction of the periodontal pockets.

Conclusion

CGF application following surgical extraction provides an easy, low-cost, and efficient option for alveolar ridge preservation. Thus, the use of CGF by dentists during dental extractions may be encouraged, particularly when alveolar ridge preservation is required.

Clinical trial registration

TCTR identification, TCTR20221028003.

Comparison of the clinical efficacy of concentrated growth factor and advanced platelet-rich fibrin in the treatment of type I multiple gingival recessions: a controlled randomized clinical trial

OBJECTIVES

The purpose of this randomized controlled clinical trial was to compare and evaluate the clinical effects of concentrated growth factor (CGF) and advanced platelet-rich fibrin (A-PRF) applied together with coronally advanced flap (CAF) technique using a microsurgical approach in the treatment of type I multiple gingival recessions (GR).

MATERIALS AND METHODS

Sixteen patients with multiple recession defects (Cairo type I) were included in this randomized and controlled study. Forty-five gingival recession defects were randomly equally divided into three groups (n = 15): CAF + CGF (test site); CAF + A-PRF (test site), and CAF alone (control site). Clinical attachment level (CAL), vertical gingival recession (VGR), horizontal gingival recession (HGR), gingival thickness (GT), width of keratinized gingiva (KGW), percentages of the mean (MRC), and complete root coverage (CRC), patient esthetic score (PES), and hypersensitivity score (HS) were recorded at baseline and 6 months after surgery. Patient comfort score (PCS) was evaluated at the day of surgery.

RESULTS

Significant improvements were determined in CAL, VGR, HGR, KGW, and GT at 6 months when compared to baseline levels in intra-group comparisons for all groups, and also GT was increased in CAF + A-PRF and CAF + CGF compared to CAF alone at 6 months in intergroup comparisons (p < 0.05). At 6 months, MRC was detected 85.66 ± 22.68% in the CAF + CGF, 90.88 ± 20.87% in the CAF + A-PRF, and 75.10 ± 32,37% in the CAF alone, and a significant increase was detected in the CAF + A-PRF group compared to CAF alone (p < 0.05). CRC in CAF + CGF was 66.66%, in CAF + A-PRF 80% and in CAF alone was 53.33% (p > 0.05). PES and HS values showed significant improvement from baseline to 6 months for all groups and also in CAF + CGF and CAF + A-PRF compared to CAF alone at 6 months in intergroup comparisons (p < 0.05).

CONCLUSIONS

The present study showed that the use of A-PRF and CGF membranes in GR therapy may have an additional benefit in GT increase and also A-PRF may increase the percentages of MRC. The use of A-PRF and CGF membranes may be beneficial in terms of improving patient-related parameters.

CLINICAL RELEVANCE

A-PRF and CGF may be superior to CAF alone in terms of patient-related parameters and GT increase in multiple recession defects.

TRIAL REGISTRATION NUMBER

17578e02-00a9-4a41-8c8d-42a637143531.

Efficacy of biologics in root coverage and gingival augmentation therapy: An American Academy of Periodontology best evidence systematic review and network meta-analysis

BACKGROUND

The aim of this systematic review was to assess the efficacy of three biologics, namely autologous blood-derived products (ABPs), enamel matrix derivatives (EMD) and recombinant human platelet-derived growth factor BB (rhPDGF-BB), in root coverage and gingival augmentation therapy.

METHODS

The protocol of this PRISMA 2020-compliant systematic review was registered in PROSPERO (CRD42021285917). After study selection, data of interest were extracted. A network meta-analysis (NMA) was conducted to assess the effect of different surgical interventions on the main clinical outcomes of interest (i.e., mean root coverage [MRC%], complete root coverage [CRC%], keratinized tissue width [KTW], gingival thickness [GT] change, and recession depth [RD] reduction).

RESULTS

A total of 48 trials reported in 55 articles were selected. All studies reported on the treatment of gingival recession defects for root coverage purposes. Forty-six treatment arms from 24 trials were included in the NMA. These arms consisted of treatment with coronally advanced flap (CAF) alone, EMD + CAF, platelet-rich fibrin (PRF) + CAF, and subepithelial connective tissue graft (SCTG) + CAF. Regarding MRC%, SCTG+CAF was associated with a significant higher estimate (13.41%, 95% CI [8.06-18.75], P <  0.01), while EMD+CAF (6.68%, 95% CI [-0.03 to 13.4], P = 0.061) and PRF+CAF (1.03%, 95% CI [-5.65 to 7.72], P = 0.71) failed to show statistically significant differences compared with CAF alone (control group) or with each other. Similarly, only SCTG+CAF led to a significantly higher CRC% (14.41%, 95% CI [4.21 to 24.61], P < 0.01), while treatment arms EMD + CAF (13.48%, 95% CI [-3.34 to 30.32], P = 0.11) and PRF+CAF (-0.91%, 95% CI [-15.38, 13.57], p = 0.81) did not show significant differences compared with CAF alone or with each other. Differences in the CI of PRF+CAF (symmetrical around a zero adjunctive effect) and EMD+CAF (non-symmetrical) suggest that EMD could have some additional value compared with PRF. Treatment with SCTG+CAF led to a statistically significant higher RD reduction (-0.39 mm, 95% CI [-0.55 to 0.22], P < 0.01), however EMD+CAF (-0.13 mm, 95% CI [-0.29 to 0.01], P = 0.08) and PRF+CAF (-0.06 mm, 95% CI [-0.23 to 0.09], P = 0.39) failed to show significant differences compared with CAF or with each other. While SCTG+CAF was associated with a statistically significant higher gain of KTW (0.71 mm, 95% CI [0.48 to 0.93], P < 0.01), EMD+CAF (0.24 mm, 95% CI [-0.02 to 0.51], P = 0.08) and PRF+CAF (0.08 mm, 95% CI [-0.23 to 0.41], P = 0.58) did not result into significant changes compared with CAF alone or with each other. Regarding the use of rhPDGF-BB+CAF, although available studies have reported equivalent results compared with SCTG+CAF, evidence is very limited.

CONCLUSIONS

The use of ABPs, EMD, or rhPDGF-BB in conjunction with a CAF for root coverage purposes is safe and generally promotes significant improvements respective to baseline clinical parameters. However, the adjunctive use of ABPs and EMD does not provide substantial additional improvements in terms of clinical outcomes and patient-reported outcome measures to those achieved using CAF alone, when baseline KTW is >2 mm. Both PRF+CAF and EMD+CAF rendered inferior MRC%, CRC%, RD reduction, and KTW gain compared with SCTG+CAF, which should still be considered the gold-standard in root coverage therapy. Although some studies have reported equivalent results for rhPDGF-BB+CAF compared with the gold-standard intervention, limited evidence precludes formal comparisons with CAF or SCTG+CAF that could be extrapolated to guide clinical practice.

Splith mouth randomized control trial comparison of T‐PRF and subepithelial connective tissue graft in the treatment of maxillar multiple gingival recessions

AIM

The aim of this study is to compare the treatment efficacy of the bilateral multiple gingival recession areas with a titanium-platelet-rich-fibrin (T-PRF) and subepithelial connective tissue graft (SCTG) combined with a modified coronal advanced flap (MCAF) and the clinical results.

METHOD

In the study, 118 maxillary bilateral multiple Miller I recessions were treated. Gingival index, plaque index, probing pocket depth, gingival thickness, recession height, recession width, keratinized gingival width and open root surface area were measured at baseline and at 6 months. Postoperative pain levels Visual Analog Scale, healing status, wound healing index evaluated with. The results of both groups pre and postoperative were compared.

RESULTS

The initial recession height was 2.15 ± 1.0 mm in the T-PRF group; 2.04 ± 0.80 mm in the SCTG group. After 6 months, the mean root closure rate was 61.77%, 75.31% in T-PRF and SCTG group, respectively. Clinical attachment gain was achieved in both groups compared to baseline. When the results were compared, the gains achieved in the SCTG group were statistically significantly higher. İt was determined that patient satisfaction was higher in T-PRF group and wound healing was faster.

CONCLUSION

Considering the advantages of T-PRF such as providing effective results in the treatment of defects, patient satisfaction and rapid recovery; It can be applied as an alternative to SCTG.

CLINICAL SIGNIFICANCE

T-PRF can be an alternative to SCTG in the treatment of gingival recessions.

Emerging roles of platelet concentrates and platelet-derived extracellular vesicles in regenerative periodontology and implant dentistry

Platelet concentrates (PCs) are easily obtained from autogenous whole blood after centrifugation and have evolved through three generations of development to include platelet-rich plasma, platelet-rich fibrin, and concentrated growth factor. Currently, PCs are widely used for sinus floor elevation, alveolar ridge preservation, periodontal bone defects, guided bone regeneration, and treatment of gingival recession. More recently, PCs have been leveraged for tissue regeneration to promote oral soft and hard tissue regeneration in implant dentistry and regenerative periodontology. PCs are ideal for this purpose because they have a high concentration of platelets, growth factors, and cytokines. Platelets have been shown to release extracellular vesicles (P-EVs), which are thought to be essential for PC-induced tissue regeneration. This study reviewed the clinical application of PCs and P-EVs for implant surgery and periodontal tissue regeneration.

Effects of autologous concentrated growth factor on gingival thickness in periodontal accelerated osteogenic orthodontics: a 6-month randomized controlled trial

Background

Earlier studies have not given clear results of concentrated growth factor (CGF) on gingival thickness (GT) in periodontal accelerated osteogenic orthodontics (PAOO). This randomized controlled trial aimed to evaluate the effects of CGF on GT in patients with thin gingival phenotype undergoing PAOO.

Methods

Forty four patients presenting 264 anterior mandibular teeth were recruited and randomly allocated to one of the groups: test—positioning of autologous CGF after PAOO or control—positioning of a collagen membrane after PAOO. GT, gingival height (GH), buccal alveolar bone thickness (BT), and buccal alveolar bone height (BH) were evaluated depending on cross-sectional CBCT images at t0 (before surgery) and t1(6 months after surgery).

Results

GT were increased in both groups at t1 compared to t0. Yet, higher values were observed in the test group (from 0.94 ± 0.23 to 1.31 ± 0.33 mm) compared to the control group (from 0.94 ± 0.19 to 1.02 ± 0.16 mm) (p < 0.05). Moreover, in the intergroup comparison, GT at t1 in the test group was significantly higher compared to the control group (p < 0.01). Furthermore, the GT of central incisors, lateral incisors and canine teeth all showed significantly changes compared with baseline and the test group showed higher increase (p < 0.01). No statistically significant difference were found in GH, BT, BH and all clinical parameters between two groups at t1 (p > 0.05).

Conclusions

Within the limitation of this study, gingival thickness could be increased by using CGF in PAOO for the patients with thin gingival phenotype.

Trial registration The study was registered in Chinese Clinical Trial Registry (http://www.chictr.org.cn/index.aspx) under the number ChiCTRINR17013346, Registered 11 November 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01967-5.

Soft Tissue Regeneration at Natural Teeth

This article provides an overview of the best-documented surgical techniques for recession coverage and draws conclusions for the clinician. Use of a connective tissue graft with either coronally advanced flap (CAF) or tunnel is the most predictable technique for the treatment of single and multiple gingival recessions. Long-term results exist only for CAF with/without connective tissue graft providing evidence for long-term stability with only minor relapses. Soft tissue replacement materials and biologics may represent a valuable modality to additionally improve the clinical outcomes obtained with CAF alone or, in certain clinical situations, to serve as an alternative to autogenous tissue.

Treatment of multiple gingival recessions with concentrated growth factor membrane and coronally advanced tunnel technique via digital measurements: A randomized controlled clinical trial

Background/purpose

Research into biomaterial alternatives to connective tissue grafts (CTG) is a research hotspot. The purpose of this clinical trial was to compare the effectiveness of root coverage through tunnel technique with concentrated growth factor (CGF) vs CTG in treating multiple gingival recessions using digital measurements.

Materials and methods

Seventy Cairo Class I multiple gingival recessions (in 28 patients) were treated with either CGF or CTG combined with coronally advanced tunnel technique. Digital models were obtained at baseline, 2 weeks, 6 weeks, and 6 months post-op to compare the gain in gingival height, area, volume, and thickness. Tooth sensitivity, post-operative pain, and healing index were also recorded.

Results

Complete root coverage at 6 months post-op were 47.06% in the CGF group and 77.78% in the CTG groups. Mean root coverages were 80.55% and 96.18%, respectively. No statistical difference was demonstrated between the two groups in terms of gingival area gain at 2 weeks post-op, but the CTG group had greater increases in gingival height, area, volume, and thickness in the period after 2 weeks post-op. Pain scores were statistically significantly lower in the CGF group. At 6 months post-op, sensitivity scores decreased more significantly in the CTG group.

Conclusion

Digital measurements revealed post-operative gingival shrinkage was more pronounced in the CGF group than in the CTG group when combined with coronally advanced tunnel technique. Despite the ease-of-use and minimal post-operative discomfort, it is difficult to achieve similar root coverage outcomes to CTG when using CGF alone in treating multiple gingival recessions.

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.

Use of PRP, PRF and CGF in Periodontal Regeneration and Facial Rejuvenation-A Narrative Review

Growth factors (GFs) play a vital role in cell proliferation, migration, differentiation and angiogenesis. Autologous platelet concentrates (APCs) which contain high levels of GFs make them especially suitable for periodontal regeneration and facial rejuvenation. The main generations of APCs presented are platelet-rich plasma (PRP), platelet-rich fibrin (PRF) and concentrated growth factor (CGF) techniques. The purpose of this review is to provide the clinician with an overview of APCs' evolution over the past decade in order to give reliable and useful information to be used in clinical work. This review summarizes the most interesting and novel articles published between 1997 and 2020. Electronic and manual searches were conducted in the following databases: Pubmed, Scopus, Cochrane Library and Embase. The following keywords were used: growth factors, VEGF, TGF-b1, PRP, PRF, CGF and periodontal regeneration and/or facial rejuvenation. A total of 73 articles were finally included. The review then addresses the uses of the three different techniques in the two disciplines, as well as the advantages and limitations of each technique. Overall, PRP is mainly used in cases of hard and soft tissue procedures, while PRF is used in gingival recession and the treatment of furcation and intrabony defects; CGF is mainly used in bone 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.

Platelet-Rich Fibrin in Single and Multiple Coronally Advanced Flap for Type 1 Recession: An Updated Systematic Review and Meta-Analysis

Background and Objectives: The aim of the present systematic review and meta-analysis was to investigate the efficacy of leukocyte–platelet-rich fibrin (L-PRF) in addition to coronally advanced flap (CAF) for the treatment of both single and multiple gingival recessions (GRs) compared to the CAF alone and to the adjunct of connective tissue graft (CTG). Root coverage outcomes using platelet concentrates have gained increased interest. In particular, it has been suggested that adding L-PRF to CAF may provide further benefits in the treatment of GRs. Materials and Methods: An electronic and manual literature search was conducted to identify randomized controlled trials (RTCs) investigating root coverage outcomes with CAF + L-PRF. The outcomes of interest included mean root coverage (mRC), recession reduction, keratinized tissue width (KTW) gain, gingival thickness (GT) gain, and patient-reported outcome measures (PROms) such as pain perception and discomfort. Results: A total of 275 patients and 611 surgical sites were analyzed. L-PRF in adjunct to single CAF seems to show statistically significant results regarding clinical attachment level (CAL) with a weighted means (WM) 0.43 95% CI (−0.04, 0.91), p < 0.0001, GT (WM 0.17 95% CI (−0.02, 0.36), p < 0.0001, and mRC (WM 13.95 95% CI (−1.99, 29.88) p < 0.0001, compared to single CAF alone. Interesting results were obtained from the adjunct of PRF to multiple CAF with respect to multiple CAF alone with an increase in the mRC WM 0.07 95% CI (−30.22, 30.35), p = 0.0001, and PPD change WM 0.26 95% CI (−0.06, 0.58), p < 00001. On the other hand, no statistically significant data were obtained when L-PRF was added to single or multiple CAF combined with CTG according to the included outcomes such as mRC (p = 0.03 overall). Conclusions: L-PRF is a valid alternative to CAF alone. L-PRF compared to CTG in single and multiple CAF showed statistically significant results regarding pain perception and discomfort PROms (p < 0.0001). However, CTG remains the gold standard for treating gingival recession.

The effect of concentrated growth factor (CGF) in the surgical treatment of medication-related osteonecrosis of the jaw (MRONJ) in osteoporosis patients: a randomized controlled study

OBJECTIVES

The purpose of this present study was to evaluate the efficiency of the growth factors delivered by concentrated growth factor (CGF) on the healing process of osteoporotic patients with medication-related osteonecrosis of the jaws (MRONJ).

METHODS

This randomized controlled study was composed of osteoporotic female patients who were treated with oral bisphosphonates (BPs) and diagnosed with MRONJ. For the CGF group, each patient was treated with a local application of CGF at the surgical site after removing the necrotic bone, while the surgical area was primarily closed as traditional surgical therapy for the control group. The patients underwent clinical examinations for 6 months postoperatively to check the presence of infection and dehiscence.

RESULTS

Complete healing was achieved in 19 patients of 28 patients (mean age: CGF group, 73.57 ± 5.1; control group, 73.64 ± 5.49) diagnosed with MRONJ. There was no significant difference in post-op healing data between groups during healing periods (p > 0.05). In the CGF group (n = 14) in three cases, bone exposure without infection was detected, and one of them showed a recurrent infection. In the control group (n = 14) in six cases, bone exposure without infection was detected, and three of them also showed recurrent infection.

CONCLUSION

Although our results were not statistically significant, our findings suggest that the local application of CGF appears to be an effective approach to the surgical treatment of MRONJ in osteoporosis patients by improving tissue regeneration.

CLINICAL RELEVANCE

A specific treatment protocol to manage MRONJ is still controversial. This study justifies that CGF can be used in combination with surgical treatment.

Considerations for Clinical Use of Concentrated Growth Factor in Maxillofacial Regenerative Medicine

Different strategies have been utilized to facilitate mineralized/soft tissues. Concentrated growth factor (CGF) emerges as a promising biomaterial for regenerative therapy due to high levels of platelets, growth factors, and nucleated cells entrapped in the fibrin scaffold. This review aimed to collect extensive studies on CGF used in maxillofacial regenerative medicine, discussing current obstacles, and expressing some considerations of CGF use. Articles were retrieved systematically without time limitation. In total, 27 human studies were included and separated accordingly. In general, CGF has been most evaluated in implant related therapy and maxillofacial bone regeneration where a majority of articles have revealed favorable outcomes. Little studies have supported the effects on improving probing periodontal depth reductions and clinical attachment level gains for intrabony and furcation defect regeneration. Very little data with high-level evidence was available directly to investigate its effects on the soft tissue regeneration and postoperative complications reduction. The evidence supporting the clinical efficacy of CGF in maxillofacial regenerative medicine is limited. Some conflicting results are worrisome. In addition, the characterization of CGF preparation protocols and CGF's components was not performed in most studies. Further studies should make a consensus on standardized end-product of CGF including characterization of protocols and optimal ratio of CGF' components. Defined algorithms and evidence-based protocols for the clinical use of CGF should be also available.

Gingival Thickness and Outcome of Periodontal Plastic Surgery Procedures: A Meta-regression Analysis

OBJECTIVE

To evaluate the impact of soft tissue thickness (STT) on root coverage achieved with different periodontal plastic surgery procedures.

BACKGROUND

Gingival recession has been managed successfully through various surgical approaches, with great variability in outcomes. Anatomic characteristics of the recipient site and selected technique account in part for this variability. Gingival flap thickness is one of the most critical site-related characteristics.

METHODS

An electronic search was conducted on the major databases (PubMed, Embase, Web of Science). Human prospective studies with at least 6 mo of follow-up and with a numeric baseline measurement for gingival thickness were eligible. Only studies including nonsmoking patients were considered. Variables included surgical approach, participant characteristics, local anatomic factors, and follow-up time. Primary outcome was mean percentage root coverage (%RC) achieved, and complete root coverage was a secondary outcome.

RESULTS

A total of 42 studies were included (35 randomized controlled trials, 5 case series, 1 prospective cohort study, and 1 controlled clinical trial). Across studies, the pooled %RC was 81.9% (95% CI, 79.1% to 84.7%). The %RC was not significantly associated (P = 0.267) with baseline soft tissue thickness; however there was a significant (P = 0.031) inverse relationship between STT and %RC after 12-mo follow-up. Subgroup analysis showed that for no graft, there was a significant (P = 0.025) positive relationship between STT and %RC with the exclusion of the single outlier study based on STT.

CONCLUSIONS

STT plays a limited role in predicting root coverage across all approaches; when flaps are performed with no graft, the effect of STT is most critical. The length of time following surgery appears to influence outcomes, with 12-mo follow-up offering greater insight.

KNOWLEDGE TRANSFER STATEMENT

The results of this study can suggest to clinicians which periodontal plastic surgery technique to employ when treating challenging cases. In particular, it can be helpful when selecting the treatment approach to treat thin phenotype sites. This study could help clinicians provide a more appropriate treatment decision in such cases.

Use of platelet-rich fibrin for the treatment of gingival recessions: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review and meta-analysis was to compare the use of platelet-rich fibrin (PRF) with other commonly utilized treatment modalities for root coverage procedures.

MATERIALS AND METHODS

The eligibility criteria comprised randomized controlled trials (RCTs) comparing the performance of PRF with that of other modalities in the treatment of Miller class I or II (Cairo RT I) gingival recessions. Studies were classified into 5 categories as follows: (1) coronally advanced flap (CAF) alone vs CAF/PRF, (2) CAF/connective tissue graft (CAF/CTG) vs CAF/PRF, (3) CAF/enamel matrix derivative (CAF/EMD) vs CAF/PRF, (4) CAF/amnion membrane (CAF/AM) vs CAF/PRF, and (5) CAF/CTG vs CAF/CTG/PRF. Studies were evaluated for percentage of relative root coverage (rRC; primary outcome), clinical attachment level (CAL), keratinized mucosa width (KMW), and probing depth (PD) (secondary outcomes).

RESULTS

From 976 articles identified, 17 RCTs were included. The use of PRF statistically significantly increased rRC and CAL compared with CAF alone. No change in KMW or reduction in PD was reported. Compared with PRF, CTG resulted in statistically significantly better KMW and RC. No statistically significant differences were reported between the CAF/PRF and CAF/EMD groups or between the CAF/PRF and CAF/AM groups for any of the investigated parameters.

CONCLUSIONS

The use of CAF/PRF improved rRC and CAL compared with the use of CAF alone. While similar outcomes were observed between CAF/PRF and CAF/CTG for CAL and PD change, the latter group led to statistically significantly better outcomes in terms of rRC and KTW. In summary, the use of PRF in conjunction with CAF may represent a valid treatment modality for gingival recessions exhibiting adequate baseline KMW.

CLINICAL RELEVANCE

The data indicate that the use of PRF in conjunction with CAF statistically significantly improves rRC when compared with CAF alone but did not improve KMW. Therefore, in cases with limited baseline KMW, the use of CTG may be preferred over PRF.

Gingival recession treatment with concentrated growth factor membrane: a comparative clinical trial

Objective

This clinical trial sought to evaluate the clinical effectiveness of concentrated growth factor (CGF) and compare it with connective tissue graft (CTG) with coronally advanced flap (CAF) in the treatment of Miller Class I gingival recessions (GR).

Methodology

This split-mouth study included 74 Miller Class I isolated (24 teeth) or multiple (50 teeth) GRs in 23 jaws of 19 patients. GRs were randomly treated using CGF (test group: 37 teeth; 12 teeth in isolated GRs, 25 teeth in multiple GRs) or CTG with CAF (control group: 37 teeth;12 teeth isolated GRs, 25 teeth in multiple GRs). Clinical variables, plaque index (PI), gingival index (GI), probing depth (PD), recession depth (RD), recession width (RW), clinical attachment level (CAL), keratinized tissue thickness (KTT), keratinized tissue width (KTW), and root coverage (RC) were assessed at the baseline as well as at three and six months post-surgery. Healing index (HI) were obtained in the second and third weeks post-surgery. Postoperative pain was assessed for the first seven days using a horizontal visual analog scale (VAS).

Results

No significant change was observed in PI, GI, or PD values in either the intergroup or the intragroup comparisons. A statistically significant decrease was observed in CAL, RD, and RW, and KTT increased in all groups at three and six months compared with the baseline. The control group had greater increases in KTW, KTT, and RC at three and six months. No significant difference was found in CAL or RD at the third and sixth months between the two groups. Healing was found to be similar for both groups in the second and third weeks post-surgery. The VAS values in the control group were higher than in the test group, especially at the second, fourth, fifth, and seventh days postoperatively.

Conclusions

CTG is superior to CGF with CAF for increasing KTT, KTW, and RC. CGF may be preferable due to decreased postoperative pain.

In vitro and in vivo effects of concentrated growth factor on cells and tissues

This article reviews the biological outcome of the concentrated growth factor (CGF), a new platelet derivative used for tissue regeneration, in published articles related to the use of this product in basic and clinical studies. An electronic literature research using PubMed and SCOPUS was performed using combination of keywords: "concentrated growth factor" (OR "CGF"), AND "stem cells," AND "cells" OR "cell proliferation" OR "cell migration" OR "cell differentiation," AND "repair" OR "survival" OR "revitalization," AND "tissue" OR "bone." Forty-five articles that were published between 2012 and 2020 met the inclusion criteria. These studies have used CGF as fresh solid form, freeze-dried, membrane, extract, or exudate. Most studies demonstrate the positive effects of CGF in a dose-dependent manner under certain concentrations. Studies comparing CGF with other platelet concentrates, report lower efficiency, no statistically significant differences, or better results for CGF. Combination of CGF with stem cells and biomaterials significantly improves bone regeneration and the effect of allograft or collagen membrane is better than CGF alone. For a better examination of the biological outcomes of CGF, the standardization of CGF preparation regarding the choice of the test tube material for blood collection, the required volume of blood, the necessary count of platelets in CGF, and the most appropriate type of CGF are recommended.

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.

One-Year Results Evaluating the Effects of Concentrated Growth Factors on the Healing of Intrabony Defects Treated with or without Bone Substitute in Chronic Periodontitis

Background

The restoration of damaged periodontium, especially one-wall intrabony defects, is a major challenge for clinicians. Concentrated growth factors (CGF) are a 100% autologous fibrin with multiple concentrated growth factors. The rigid fibrin structure of CGF makes it possible to preserve or reconstruct the initial bone volume. The aim of this study was to evaluate the clinical healing patterns after surgical application of CGF with and without a Bio-Oss graft in one-wall infrabony defects.

Material/Methods

We randomly divided 120 one-wall intrabony defects in 54 patients into 4 groups: flap surgery alone (Group 1), flap surgery with autologous CGF (Group 2), flap surgery with Bio-Oss (Group 3), and flap surgery with CGF+Bio-Oss (Group 4). Clinical parameters such as probing depth (PD) and clinical attachment level (CAL) change were recorded at baseline and at 6 and 12 months postoperatively.

Results

At 12 months postoperatively, Group 2 showed significant improvement in clinical parameters over Group 1 (P<0.05) and the results were significantly greater in Groups 3 and 4 compared to the other groups (P<0.05). Although no significant difference was noted between Groups 3 and 4 in clinical parameters (P>0.05) compared to Group 3, the mean change of CAL at 6–12 months in Group 4 was not significant (P>0.05).

Conclusions

CGF reduced periodontal intrabony defects depth and, when mixed with Bio-Oss, CGF showed better results in the early period and the effect was more stable.

The potential application of concentrated growth factor in pulp regeneration: an in vitro and in vivo study

Background

Concentrated growth factor (CGF), as a natural biomaterial, is known to contain platelets, cytokines, and growth factors to facilitate the healing process, but there has been little information acquired in regenerative endodontics. The purpose of this study was to investigate the effects of CGF on proliferation, migration, and differentiation in human dental stem pulp cells (hDPSCs) exposed to lipopolysaccharide (LPS) in vitro and its potential role in pulp regeneration of the immature teeth in vivo.

Methods

In vitro experiments: CGF-conditioned medium were extracted by freeze-dried method. hDPSCs were isolated and identified. The proliferative potential of hDPSCs with different concentration of CGF and LPS was evaluated by Cell Counting Kit-8. Migration capacity was analyzed by Transwell assays, odonto/osteoblastic differentiation was determined by measuring alkaline phosphatase (ALP) activity using ALP staining, and the extent of mineralization was evaluated by using Alizarin red S staining. The mRNA expression level of DMP-1, DSPP, OPN, Runx2, and OCN were determined by quantitative polymerase chain reaction (qPCR).

In vivo experiments: CGF were used as root canal filling agent of the immature single-rooted teeth in the beagle dogs. The teeth were then radiographed, extracted, fixed, demineralized, and subjected to histologic analyses at 8 weeks. The newly formed dentine-pulp complex and the development of apical foramen were evaluated by the hematoxylin-eosin (HE) and Masson trichrome technique. Soft tissues were analyzed by immunohistochemical staining of vascular endothelial growth factor (VEGF) and Nestin.

Results

In vitro experiments: The cultured cells exhibited the characteristics of mesenchymal stem cell. The treatment of LPS significantly increased the expression of TNF-α, IL-1β, IL-6, and IL-8 in hDPSCs, and CGF inhibited the mRNA expression of IL-8 in LPS-stimulated hDPSCs. The proliferation values of the CGF group in LPS-stimulated hDPSCs were significantly higher than that of the control group from day 3 to day 7 (P < 0.05). In addition, the number of migratory cells of the CGF group was greater than that of the control group at 24 h with or without LPS treatment. ALP activities increased gradually in both groups from day 4 to day 7. The mineralized nodules and the expression of odontogenesis-related genes DMP-1 and DSPP, osteogenesis-related genes OPN, Runx2, and OCN were dramatically enhanced by CGF in LPS-stimulated hDPSCs at days 21 and 28.

In vivo experiments: In CGF treated group, the results of radiograph, HE, and Masson trichrome staining showed a continuing developed tooth of the immature teeth in the beagle dogs (i.e., the ingrowth of soft tissues into the root canal, the thickened internal root dentin walls, and the closed apex), which resembled the normal tooth development in the positive control group. The immunohistochemical staining showed that VEGF and Nestin were both moderately expressed in the regenerated pulp-like tissues which indicating the vascularization and innervation.

Conclusions

CGF has a positive effect on the proliferation, migration, and differentiation of hDPSCs exposed to LPS in vitro, and it can also promote the regeneration of dentine-pulp complex of the immature teeth in the beagle dogs in vivo. Therefore, CGF could be a promising alternative biomaterial in regenerative endodontics.

Modulation of proliferation and differentiation of gingiva‑derived mesenchymal stem cells by concentrated growth factors: Potential implications in tissue engineering for dental regeneration and repair

The aim of the present study was to evaluate the proliferation and osteogenic differentiation ability of gingiva-derived mesenchymal stem cells (GMSCs) cultured with different concentrations of concentrated growth factors (CGF). GMSCs were isolated from gingival connective tissues and characterized by flow cytometry, immunofluorescence staining and immunohistochemical staining. Cell proliferation activity was determined by the MTT assay, and the effect of CGF on MCSCs was detected with the Cell Counting Kit (CCK)-8 assay. Mineralization induction was evaluated by alkaline phosphatase (ALP)-positive cell staining and mineralized nodule formation assay. Dentin matrix acidic phosphoprotein (DMP)1, dentin sialophosphoprotein (DSPP), bone morphogenetic protein (BMP)2 and runt-related transcription factor (RUNX)2 mRNA and protein expression were evaluated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis and western blotting. The flow cytometry, immunofluorescence staining and immunohistochemical staining results indicated that the cultured cells were GMSCs. The MTT assay results revealed that the third-generation gingival stem cells exhibited the highest proliferative capacity, and the CCK-8 results indicated that 10% CGF achieved the most prominent promotion of GMSC proliferation. ALP activity analysis and mineralized nodule assay demonstrated that CGF may successfully induce osteogenic differentiation of GMSCs, whereas RT-qPCR and western blot analyses demonstrated that CGF is involved in the differentiation of GMSCs by regulating the expression of DMP1, DSPP, BMP2 and RUNX2 (P<0.05). In conclusion, CGF were demonstrated to promote the proliferation and osteogenic differentiation of GMSCs. Therefore, CGF may be applied in tissue engineering for tooth regeneration and repair.

Autologous platelet concentrates for treating periodontal infrabony defects

BACKGROUND

Periodontal disease is a condition affecting tooth-supporting tissues (gingiva, alveolar bone, periodontal ligament, and cementum), with the potential of introducing severe adverse effects on oral health. It has a complex pathogenesis which involves the combination of specific micro-organisms and a predisposing host response. Infrabony defects are one of the morphological types of alveolar bone defects that can be observed during periodontitis. Recent approaches for the treatment of infrabony defects, combine advanced surgical techniques with platelet-derived growth factors. These are naturally synthesized polypeptides, acting as mediators for various cellular activities during wound healing. It is believed that the adjunctive use of autologous platelet concentrates to periodontal surgical procedures produces a better and more predictable outcome for the treatment of infrabony defects.

OBJECTIVES

To assess the effects of autologous platelet concentrates (APC) used as an adjunct to periodontal surgical therapies (open flap debridement (OFD), OFD combined with bone grafting (BG), guided tissue regeneration (GTR), OFD combined with enamel matrix derivative (EMD)) for the treatment of infrabony defects.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 27 February 2018); the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 1) in the Cochrane Library (searched 27 February 2018); MEDLINE Ovid (1946 to 27 February 2018); Embase Ovid (1980 to 27 February 2018); and LILACS BIREME Virtual Health Library (from 1982 to 27 February 2018). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials on 27 February 2018. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of both parallel and split-mouth design, involving patients with infrabony defects requiring surgical treatment. Studies had to compare treatment outcomes of a specific surgical technique combined with APC, with the same technique when used alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted data extraction and risk of bias assessment, and analysed data following Cochrane methods. The primary outcomes assessed were: change in probing pocket depth (PD), change in clinical attachment level (CAL), and change in radiographic bone defect filling (RBF). We organised all data in four groups, each comparing a specific surgical technique when applied with the adjunct of APC or alone: 1. APC + OFD versus OFD, 2. APC + OFD + BG versus OFD + BG, 3. APC + GTR versus GTR, and 4. APC + EMD versus EMD.

MAIN RESULTS

We included 38 RCTs. Twenty-two had a split-mouth design, and 16 had a parallel design. The overall evaluated data included 1402 defects. Two studies were at unclear overall risk of bias, while the remaining 36 studies had a high overall risk of bias.1. APC + OFD versus OFD alone Twelve studies were included in this comparison, with a total of 510 infrabony defects. There is evidence of an advantage in using APC globally from split-mouth and parallel studies for all three primary outcomes: PD (mean difference (MD) 1.29 mm, 95% confidence interval (CI) 1.00 to 1.58 mm; P < 0.001; 12 studies; 510 defects; very low-quality evidence); CAL (MD 1.47 mm, 95% CI 1.11 to 1.82 mm; P < 0.001; 12 studies; 510 defects; very low-quality evidence); and RBF (MD 34.26%, 95% CI 30.07% to 38.46%; P < 0.001; 9 studies; 401 defects; very low-quality evidence).2. APC + OFD + BG versus OFD + BG Seventeen studies were included in this comparison, with a total of 569 infrabony defects. Considering all follow-ups, as well as 3 to 6 months and 9 to 12 months, there is evidence of an advantage in using APC from both split-mouth and parallel studies for all three primary outcomes: PD (MD 0.54 mm, 95% CI 0.33 to 0.75 mm; P < 0.001; 17 studies; 569 defects; very low-quality evidence); CAL (MD 0.72 mm, 95% CI 0.43 to 1.00 mm; P < 0.001; 17 studies; 569 defects; very low-quality evidence); and RBF (MD 8.10%, 95% CI 5.26% to 10.94%; P < 0.001; 11 studies; 420 defects; very low-quality evidence).3. APC + GTR versus GTR alone Seven studies were included in this comparison, with a total of 248 infrabony defects. Considering all follow-ups, there is probably a benefit for APC for both PD (MD 0.92 mm, 95% CI -0.02 to 1.86 mm; P = 0.05; very low-quality evidence) and CAL (MD 0.42 mm, 95% CI -0.02 to 0.86 mm; P = 0.06; very low-quality evidence). However, given the wide confidence intervals, there might be a possibility of a slight benefit for the control. When considering a 3 to 6 months and a 9 to 12 months follow-up there were no benefits evidenced, except for CAL at 3 to 6 months (MD 0.54 mm, 95% CI 0.18 to 0.89 mm; P = 0.003; 3 studies; 134 defects). No RBF data were available.4. APC + EMD versus EMDTwo studies were included in this comparison, with a total of 75 infrabony defects. There is insufficient evidence of an overall advantage of using APC for all three primary outcomes: PD (MD 0.13 mm, 95% CI -0.05 to 0.30 mm; P = 0.16; 2 studies; 75 defects; very low-quality evidence), CAL (MD 0.10 mm, 95% CI -0.13 to 0.32 mm; P = 0.40; 2 studies; 75 defects; very low-quality evidence), and RBF (MD -0.60%, 95% CI -6.21% to 5.01%; P = 0.83; 1 study; 49 defects; very low-quality evidence).All studies in all groups reported a survival rate of 100% for the treated teeth. No complete pocket closure was reported. No quantitative analysis regarding patients' quality of life was possible.

AUTHORS' CONCLUSIONS

There is very low-quality evidence that the adjunct of APC to OFD or OFD + BG when treating infrabony defects may improve probing pocket depth, clinical attachment level, and radiographic bone defect filling. For GTR or EMD, insufficient evidence of an advantage in using APC was observed.

Root coverage procedures for treating localised and multiple recession-type defects

BACKGROUND

Gingival recession is defined as the oral exposure of the root surface due to a displacement of the gingival margin apical to the cemento-enamel junction and it is regularly linked to the deterioration of dental aesthetics. Successful treatment of recession-type defects is based on the use of predictable root coverage periodontal plastic surgery (RCPPS) procedures. This review is an update of the original version that was published in 2009.

OBJECTIVES

To evaluate the efficacy of different root coverage procedures in the treatment of single and multiple recession-type defects.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 15 January 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 12) in the Cochrane Library (searched 15 January 2018), MEDLINE Ovid (1946 to 15 January 2018), and Embase Ovid (1980 to 15 January 2018). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials (15 January 2018). No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) only of at least 6 months' duration evaluating recession areas (Miller's Class I or II ≥ 3 mm) and treated by means of RCPPS procedures.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, data extraction and risk of bias assessment were conducted independently and in duplicate. Authors were contacted for any missing information. We expressed results as random-effects models using mean differences (MD) for continuous outcomes and odds ratios (OR) for dichotomous outcomes with 95% confidence intervals (CI). We used GRADE methods to assess the quality of the body of evidence of our main comparisons.

MAIN RESULTS

We included 48 RCTs in the review. Of these, we assessed one as at low risk of bias, 12 as at high risk of bias and 35 as at unclear risk of bias. The results indicated a greater reduction in gingival recession for subepithelial connective tissue grafts (SCTG) + coronally advanced flap (CAF) compared to guided tissue regeneration with resorbable membranes (GTR rm) + CAF (MD -0.37 mm; 95% CI -0.60 to -0.13, P = 0.002; 3 studies; 98 participants; low-quality evidence). There was insufficient evidence of a difference in gingival recession reduction between acellular dermal matrix grafts (ADMG) + CAF and SCTG + CAF or between enamel matrix protein (EMP) + CAF and SCTG + CAF. Regarding clinical attachment level changes, GTR rm + CAF promoted additional gains compared to SCTG + CAF (MD 0.35; 95% CI 0.06 to 0.63, P = 0.02; 3 studies; 98 participants; low-quality evidence) but there was insufficient evidence of a difference between ADMG + CAF and SCTG + CAF or between EMP + CAF and SCTG + CAF. Greater gains in the keratinized tissue were found for SCTG + CAF when compared to EMP + CAF (MD -1.06 mm; 95% CI -1.36 to -0.76, P < 0.00001; 2 studies; 62 participants; low-quality evidence), and SCTG + CAF when compared to GTR rm + CAF (MD -1.77 mm; 95% CI -2.66 to -0.89, P < 0.0001; 3 studies; 98 participants; very low-quality evidence). There was insufficient evidence of a difference in keratinized tissue gain between ADMG + CAF and SCTG + CAF. Few data exist on aesthetic condition change related to patients' opinion and patients' preference for a specific procedure.

AUTHORS' CONCLUSIONS

Subepithelial connective tissue grafts, coronally advanced flap alone or associated with other biomaterial and guided tissue regeneration may be used as root coverage procedures for treating localised or multiple recession-type defects. The available evidence base indicates that in cases where both root coverage and gain in the width of keratinized tissue are expected, the use of subepithelial connective tissue grafts shows a slight improvement in outcome. There is also some weak evidence suggesting that acellular dermal matrix grafts appear as the soft tissue substitute that may provide the most similar outcomes to those achieved by subepithelial connective tissue grafts. RCTs are necessary to identify possible factors associated with the prognosis of each RCPPS procedure. The potential impact of bias on these outcomes is unclear.

Concentrated Growth Factor Enhanced Fat Graft Survival: A Comparative Study

BACKGROUND

Concentrated growth factors (CGFs) belong to a new generation biomaterials that concentrate large number of growth factors and CD34 stem cells in small volume of plasma.

OBJECTIVE

The purpose of this study was to evaluate the impact of the new technique, CGF, on fat graft survival, which compared with platelet-rich plasma (PRP) and platelet-rich fibrin (PRF).

MATERIALS AND METHODS

Nude mice received fat graft were divided into PRP group, PRF group, CGF group, and saline. The grafts were volumetrically and histologically evaluated at 4, 8, and 12 weeks after fat grafting. In vitro growth factor levels in PRP, PRF, and CGF were compared using enzyme-linked immunoassay method. Cell count and real-time polymerase chain reaction were used to evaluate the impact of CGF in medium on human adipose-derived stem cell (hADSC) proliferation and vascular differentiation, respectively.

RESULTS

Fat graft weight was significantly higher in the CGF group than those in the other groups, and histologic evaluation revealed greater vascularity, fewer cysts, and less fibrosis. Adding CGF to the medium maximally promoted hADSC proliferation and expressing vascular endothelial growth factor and PECAM-1.

CONCLUSION

In this preliminary study, CGF treatment improved the survival and quality of fat grafts.

Platelet-rich Fibrin: A Paradigm in Periodontal Therapy - A Systematic Review

Periodontal tissue regeneration has always been a challenge for the periodontists owing to its structural complexity. Although with tissue engineering as a growing multidisciplinary field, this aim has partially been fulfilled. In recent years, platelet-rich fibrin (PRF) has gained wide attention for its utilization as a biocompatible regenerative material not only in dental but also in medical fields. The following systematic review has gathered all the currently available in vitro, animal, and clinical studies utilizing PubMed electronic database from January 2006 to August 2016 highlighting PRF for soft and hard tissue regeneration and/or wound healing. Although results are encouraging but require further validation from clinical studies to justify the potential role of PRF in periodontal regeneration so that this relatively inexpensive autologous biomaterial can be utilized at a wider scale.

Use of platelet-rich fibrin in regenerative dentistry: a systematic review

OBJECTIVES

Research across many fields of medicine now points towards the clinical advantages of combining regenerative procedures with platelet-rich fibrin (PRF). This systematic review aimed to gather the extensive number of articles published to date on PRF in the dental field to better understand the clinical procedures where PRF may be utilized to enhance tissue/bone formation.

MATERIALS AND METHODS

Manuscripts were searched systematically until May 2016 and separated into the following categories: intrabony and furcation defect regeneration, extraction socket management, sinus lifting procedures, gingival recession treatment, and guided bone regeneration (GBR) including horizontal/vertical bone augmentation procedures. Only human randomized clinical trials were included for assessment.

RESULTS

In total, 35 articles were selected and divided accordingly (kappa = 0.94). Overall, the use of PRF has been most investigated in periodontology for the treatment of periodontal intrabony defects and gingival recessions where the majority of studies have demonstrated favorable results in soft tissue management and repair. Little to no randomized clinical trials were found for extraction socket management although PRF has been shown to significantly decrease by tenfold dry sockets of third molars. Very little to no data was available directly investigating the effects of PRF on new bone formation in GBR, horizontal/vertical bone augmentation procedures, treatment of peri-implantitis, and sinus lifting procedures.

CONCLUSIONS

Much investigation now supports the use of PRF for periodontal and soft tissue repair. Despite this, there remains a lack of well-conducted studies demonstrating convincingly the role of PRF during hard tissue bone regeneration. Future human randomized clinical studies evaluating the use of PRF on bone formation thus remain necessary.

CLINICAL RELEVANCE

PRF was shown to improve soft tissue generation and limit dimensional changes post-extraction, with little available data to date supporting its use in GBR.

Quantitative changes in palatal donor site thickness after free gingival graft harvesting: a pilot study

AIM

The aim of this study was to investigate how donor sites thickness quantitatively change over time and at different points of donor site in spontaneous palatal wound healing after free gingival graft (FGG) harvesting.

MATERIALS AND METHODS

Forty individuals were enrolled and divided into the following two groups based on the residual tissue thickness (RTT) after harvesting: Group 1, <2 mm; and Group 2, ≥2 mm. FGGs were standardized according to their dimensions and thickness and then harvested. Tissue filling was measured at three points of the defect area (mesial, central and distal) at various time points (baseline, after harvesting, and at 1, 3 and 6 months).

RESULTS

The thickness of newly formed tissue from the baseline to 1 month after harvesting was greater in Group 2 than in Group 1, whereas the thickness from 1 to 3 months and from 3 to 6 months after harvesting was greater in Group 1 than in Group 2 (p < 0.005). RTT was positively correlated with tissue filling in all the groups at all time points (p < 0.05).

CONCLUSIONS

The palatal mucosal thickness after FGG harvesting might affect the filling of the defect. Within the study period, the periphery of the palatal wounds filled earlier and to a greater extent compared with the centre of the wounds.