Efficacy of Platelet-Rich Fibrin After Mandibular Third Molar Extraction: A Systematic Review and Meta-Analysis

Efficacy of Platelet-Rich Fibrin in Preserving Alveolar Ridge Volume and Reducing Postoperative Pain in Site Preservation of Post-Extracted Sockets

Background and Objectives: In socket preservation, the goal is to minimize bone resorption after tooth extraction to maintain the volume and contour of the alveolar ridge. The use of PRF in post extraction sites may reduce ridge resorption by encouraging the growth of new bone and acting as a scaffold for tissue. In addition, PRF may enhance healing and minimize postoperative pain. The aim of this study was to evaluate the effectiveness of platelet-rich fibrin (PRF) in maintaining the ridges' dimensions at the extraction site, in the maxilla and mandible, as well as its impact on post-extraction discomfort. Methods: The study was conducted on 60 patients presenting for extraction of posterior teeth and was randomly divided into three groups: group I PRF (n = 20), group II PRF + collagen (n = 20), and group III control (n = 20). Sockets were filled with PRF (group I) and PRF + collagen (group II). At baseline and follow-up after 3 months, CBCT was used to assess the bone dimensions. The postoperative pain evaluations were performed at 24 h, 3 days, and 7 days after the tooth extraction. The pain rate was evaluated using a numerical rating scale from the British Pain Society. Results: The study examined the effects of platelet-rich fibrin (PRF) and PRF combined with collagen on the height and width of the ridges, as well as the pain experienced by the patients following alveolar ridge preservation surgery. ANOVA and t-tests were used to evaluate and compare the ridge dimensions. Comparing the results to the control group, there were no significant differences in the height or width of the ridges. However, both the PRF and PRF + Collaplug® treatments effectively reduced the short-term postoperative pain. Conclusions: The study findings suggest that platelet-rich fibrin (PRF) and PRF combined with collagen do not exert significant effects on ridge width and height compared to the standard treatment following alveolar ridge preservation. However, it is noteworthy that both the PRF and PRF + collagen treatments demonstrated efficacy in reducing postoperative pain in the short term, offering a potential advantage over standard treatment protocols.

Comprehensive evaluation of advanced platelet-rich fibrin in common complications following sagittal split ramus osteotomy: a double-blind, split-mouth, randomized clinical trial

The sagittal split ramus osteotomy (SSRO) carries potential risks and complications. A double-blind, split-mouth, randomized clinical trial was performed, involving 30 patients undergoing mandibular setback. Advanced platelet-rich fibrin (A-PRF) was applied to one side, and the other side served as a control. The volume of postoperative drainage over 24 h was recorded. At 1, 2, and 5 days, and 3 months postsurgery, nerve recovery was assessed using the two-point discrimination test (TPD), while pain was evaluated using a visual analogue scale (VAS pain). Facial swelling was evaluated by taking linear measurements from facial reference points at the same time intervals. In the treatment group, the 24-hour drainage volume was lower (P = 0.011), pain was better on day 5 (P = 0.011), and TPD was better on day 2 (P = 0.011), day 5 (P = 0.007), and 3 months postoperatively (P = 0.020) than in the control group. There was also less facial swelling in the treatment group when compared to the baseline of 3 months postoperative (day 1, P = 0.012; day 2, P = 0.001; day 5, P = 0.011). The difference in bone mineral density (HU) at 3 months between the treatment group (469.7 ± 134.2) and the control group (348.3 ± 127.2) was statistically significant (P = 0.011), in favour of the treatment group. A-PRF may reduce postoperative complications such as neurosensory disturbance of the inferior alveolar nerve, pain, swelling, and drainage while enhancing bone healing in the osteotomy gap following SSRO. TRIAL REGISTRATION: The study was registered with the Chinese Clinical Trial Register (ChiCTR2200064534).

Effect of Advanced Platelet-Rich Fibrin (A-PRF) on Postoperative Level of Pain and Swelling Following Third Molar Surgery

BACKGROUND

Postoperative pain and swelling following third molar (M3) removal can be debilitating, and there is interest in using advanced platelet-rich fibrin (A-PRF) to reduce their severity.

PURPOSE

This study compared postoperative pain and swelling between A-PRF and gelatin dressing in extraction sockets following mandibular M3 removal.

METHODS, SETTING, SAMPLE

This split-mouth, single-blinded, randomized controlled trial was completed at the Oral Surgery clinic of University of Otago between November 2020 and July 2021. Patients aged between 16 and 40 years with bilaterally impacted mandibular M3 of similar Pederson index difficulty and deemed to be American Society of Anesthesiologists (ASA) I or II comprised the study sample.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE

The exposure variable was M3 socket management. One socket received A-PRF and 1 gelatin dressing, while the other received 2 gelatin dressings.

MAIN OUTCOME VARIABLE(S)

The outcome variables were postoperative pain and swelling over 7 days. Pain was measured using the visual analog scale (VAS), and swelling using stereophotogrammetry.

COVARIATES

Demographic characteristics (gender, ethnicity, and age), dental anxiety, smoking status, Pederson index, and intraoperative surgical time were the covariates.

ANALYSES

The two sides were compared using cross-tabulations and the McNemar test for categorical and paired t-tests for continuous variables. Statistical analysis used IBM SPSS Statistics for Windows (version 28).The Alpha level was 0.05.

RESULTS

76 (87.3%) of 87 patients who met the eligibility criteria participated in the study, and 70 patients (65.7% female; age range 16-30 years) were included in the analysis. Mean visual analog scale scores showed no statistically significant difference between the A-PRF and control sides, being 29.6 (95% CI 23.9, 35.3) and 29.5 (95% CI 23.5, 35.5) on day 2, and falling to 12.6 (95% CI 8.7, 16.5) and 14.2 (95% CI 10.0, 18.4) by day 7. Likewise, mean peak facial swelling on day 2 was recorded as 6.3 cm3 (95% CI 4.9, 7.7) and 6.6 cm3 (95% CI 5.5, 7.7), and by day 7 they were 1.1 cm3 (95% CI 0.5, 1.7) and 1.0 cm3 (95% CI 0.3, 0.7) on the A-PRF and control sides, respectively.

CONCLUSIONS

A-PRF placement in M3 sockets did not reduce postoperative pain and swelling over gelatin dressing alone.

Do blood concentrates influence inflammatory signs and symptoms after mandibular third molar surgery? A systematic review and network meta-analysis of randomized clinical trials

OBJECTIVES

To investigate, through a network meta-analysis, the effectiveness of blood concentrates in reducing pain perception, trismus, and edema after mandibular third molar extraction.

MATERIALS AND METHODS

An electronic search was performed in nine databases to locate randomized clinical trials comparing blood concentrate use after mandibular third molar extraction. Two authors selected and extracted the data independently. The individual risk of bias in the studies was assessed with the RoB v2.0 tool. A network meta-analysis compared postoperative pain and trismus scores after applying different blood concentrates, using the mean difference (MD) as an effect estimate. The GRADE approach assessed the certainty of evidence.

RESULTS

Thirty-one randomized clinical trials were included in the review and 18 in the meta-analysis. Leukocyte- and platelet-rich fibrin (L-PRF) was the most used blood concentrate, followed by platelet-rich plasma (PRP). The network meta-analysis, depending on the analyzed period, evaluated up to 1240 surgeries. Among the analyzed blood concentrates, advanced platelet-rich fibrin (A-PRF) performed better among the analyzed blood concentrates, decreasing postoperative pain in 1, 2, 3, and 7 days and reducing trismus up to the inflammatory peak compared to blood clots. Only two studies had a low risk of bias.

CONCLUSIONS

Based on very low certainty of evidence, using concentrates seemed efficient compared to blood clots in reducing pain and trismus after mandibular third molar surgeries. A-PRF decreased postoperative pain throughout the evaluated time and trismus during the acute inflammatory peak.

CLINICAL RELEVANCE

A-PRF after mandibular third molar extractions performed better among the analyzed blood concentrates and seemed efficient in improving postoperative quality by decreasing inflammatory signs and symptoms.

Sema4D is diminished in leukocyte platelet-rich fibrin and impairs pre-osteoblastic MC3T3-E1 cells' functionality

OBJECTIVE

Semaphorin 4D (Sema4D) is a coupling factor expressed on osteoclasts that may hinder osteoblast differentiation. Since the leukocyte platelet-rich fibrin (L-PRF) membrane promotes growth factor concentration, this study aims to quantify the amount of Sema4D in L-PRF membranes, and analyze the impact of Sema4D on osteoblast cell function in vitro.

DESIGN

Enzyme-linked immunosorbent assay (ELISA) was used to quantify the levels of Sema4D in both L-PRF and whole blood (serum). To analyze the impairment of Sema4D on osteoblasts, MC3T3-E1 cells were induced to osteogenic differentiation and exposed to Sema4D ranging from 10 to 500 ng/ml concentrations. The following parameters were assayed: 1) cell viability by MTT assay after 24, 48, and 72 h; 2) matrix mineralization by Alizarin Red staining after 14 days, 3) Runt-related transcription factor 2 (RUNX-2), osteocalcin (OCN), osteonectin (ONC), bone sialoprotein (BSP) and alkaline phosphatase (ALP) gene expression by qPCR. For all data, the significance level was set at 5%.

RESULTS

The amount of Sema4D in the whole blood (serum) was higher than in L-PRF. Osteoblasts exposed to Sema4D at all tested concentrations exhibited a decrease in matrix mineralization formation as well in RUNX-2, OCN, ONC, BSP, and ALP gene expression (p < 0.05).

CONCLUSION

The presence of Sema4D, a molecule known for suppressing osteoblast activity, diminishes within L-PRF, enhancing its ability to facilitate bone regeneration.

Comparative Investigation of Anti-Inflammatory Effect of Platelet-Rich Fibrin after Mandibular Wisdom Tooth Surgery: A Randomized Controlled Study

This study evaluated the anti-inflammatory effect of platelet-rich fibrin (PRF) applied to the extraction socket after impacted mandibular third molar surgery with subjective and objective parameters. Forty-eight patients with impacted wisdom teeth in bilateral and similar positions were included in the study. The control group was formed with the standard surgery and the PRF group was formed with local PRF application in addition to standard procedure (n = 96). The anti-inflammatory activity of PRF on postoperative 2nd and 7th days was evaluated subjectively by clinical parameters and objectively by biochemical parameters. Postoperative 2nd- and 7th-day follow-up data of pain, edema, and trismus in the PRF group were found to be statistically significantly lower. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were found to be statistically significantly lower in the PRF group than the control in the postoperative 2nd-day follow-up period (p < 0.001). There was no statistically significant difference in interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) parameters when the PRF group and the control group were compared in both follow-up periods (p > 0.05). The study has demonstrated the effectiveness of locally applied PRF after ITM surgery via clinical parameters and objective data. The quantitative analysis of CRP and ERS can be an effective parameter in determining the amount of inflammation after ITM surgery.

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.

Comparative Study of Frequency of Alveolar Osteitis, with and without using Platelet-Rich Fibrin in Mandibular Third Molar Surgery

Introduction. Alveolar ostitis (AO) is the dissolution of blood clot due to enhanced local fibrinolysis and is caused by trauma to the jaw (direct) or because of bacterial involvement (indirect), which result in the activation of plasminogen pathway. Platelet-rich fibrin (PRF) is a platelet concentrate that comprises numerous autologous growth factors, and immune cells hence has the potential to expedite the healing process. The objective of the study was to determine the efficacy of PRF in the surgically extracted third molar in the context of its potential progress to AO. Materials and Methods. A total of 180 patients of 18–65 years with unilateral painful mandibular third molars due to caries, failed endodontics treatment, and pericoronitis were included in the study. Exclusion criteria were patients who were medically compromised, smokers, alcoholic, poor oral hygiene, third molar having associated periapical pathology, and receiving antibiotic regime in the last 2 weeks. Before starting surgical procedure, patients were randomly divided into two groups using lottery method. Group I received PRF in the extraction socket, while in Group II, the extraction site was left for normal healing as practiced in a standard procedure. Pain was assessed in terms of pain score, and it was recorded on a 10 mm visual analog scale on the first and third postoperative days. Results. Mean age of the patients was 41.35 ± 9.87 years. The mean age in Group I was 42.84 ± 10.52 years, and in Group II, it was 40.54 ± 9.52 years. Out of 180 patients, 90 (50.0%) were male and 90 (50.0%) were female, with a male-to-female ratio of 1 : 1. Frequency of AO following mandibular third molar surgery in Group I receiving PRF was 2.22% and in non-PRF group 12.22% (p-value = 0.010). Conclusion. The incidence of AO following mandibular third molar surgery was lower when PRF was used.

The effect of dental pulp stem cells and L-PRF when placed into the extraction sockets of impacted mandibular third molars on the periodontal status of adjacent second molars: a split-mouth, randomized, controlled clinical trial

PURPOSE

To compare the clinical and radiographic effectiveness of dental pulp stem cells (DPSCs) seeded onto L-PRF and L-PRF alone in the extraction socket of mandibular third molars.

METHODS

This study analyzed 13 patients who required surgical removal of impacted bilateral mandibular third molars. The main outcome measures were the probing pocket depth (PPD) and clinical attachment levels (CAL) that were recorded for the adjacent second molars (LM2) at the baseline and 6 months after surgery. The secondary outcomes were radiographic vertical bone loss (VD) and relative bone density (rBD) distal to the LM2.

RESULTS

Twenty-six LM2s were evaluated. After 6 months, the L-PRF and L-PRF + DPSC groups showed a significant reduction in PPD (1.65 ± 1.01 mm and 1.54 ± 0.78 mm) and CAL (2.23 ± 1.45 mm and 2.12 ± 0.74 mm), respectively. There was no difference between the groups for any periodontal parameters. No significant differences were found between the groups regarding the VD or rBD at the sixth month.

CONCLUSIONS

This study found that there was a significant improvement regarding the PPD, CAL, and VD measurements with the application of L-PRF, both alone and with the addition of DPSC, at the extraction socket. DPSC did not significantly contribute to the results compared to L-PRF therapy alone.

TRIAL REGISTRATION

This study was registered on 23 December 2020 on ClinicalTrials.gov under the number NCT04641533.

Does surgical removal of mandibular third molar influence the periodontal status of the adjacent second molars? A systematic review

Objective: This study aimed to assess the influence of mandibular third molar surgical removal on the periodontal status of adjacent second molars and to investigate the potential impact of the flap design. Methods: A systematic review of the literature, registered in PROSPERO, has been carried out from Pubmed and Scopus databases following PRISMA guidelines from January 2010 to January 2022. PICO method was used to select the relevant articles. Studies comparing the periodontal status of the second molar before and after mandibular third molar removal were considered. Results: Twenty-three studies involving 1067 patients were included. The two main parameters studied were periodontal pocket depth and clinical attachment level. The envelope flap and the triangular flap were the most commonly used flap techniques. Periodontal health of adjacent second molar was maintained or improved in most of the included studies. The flap design did not seem to have a significant influence either. Conclusion: Avulsion of impacted third molar in healthy young adults does not impair the periodontal health of adjacent second molars. Further studies, with higher levels of evidence, are needed to confirm these results and to identify possible risk factors (such as age, impaction depth or periodontal disease) responsible for poorer healing.

Extra-oral approach to lower third molar: a rare surgical indication

The avulsion of the impacted lower third molar is one of the most common procedures in oral surgery. Even though it is characterized by possible complications due to the lesion of lingual and inferior alveolar nerves, the intra-oral surgical approach represents the first-choice strategy when planning surgery. However, in case of ectopic tooth in the mandibular basal bone, it is appropriate to consider an extra-oral transcutaneous surgical approach. The ectopia of the inferior wisdom tooth represents a very rare clinical condition and sometimes it is even unknown by patients and dentists: further evidence of this fact is represented by the paucity of paper related to the topic that can be found in the international scientific literature. The experience of the Department of Maxillofacial Surgery of San Gerardo Hospital in Monza (Italy) in management and treatment of ectopic impacted lower third molar is exposed through the presentation of three cases of ectopic third molar. Two out of three patients, aware of the risks related to the surgical procedure, refused the treatment proposed. One patient underwent surgical avulsion of the wisdom tooth through extra-oral transcervical approach. No early or late complications have been observed. Extra-oral surgical approach for ectopic lower third molar should be considered for selected cases. Given the rarity of the clinical condition and the procedure-related risks, accurate preoperative information has to be provided to the patient by physician and the procedure should only be performed by expert and competent surgeons.

Nonpharmacological Complementary Interventions for the Management of Pain after Third Molar Surgery: An Umbrella Review of Current Meta-Analyses

Objectives. To provide a nonbiased, complete assessment of what the evidence from meta-analyses informs us about complementary and nonpharmacological treatment options for the management of pain after third molar surgery, as well as highlight any discordancy, gaps, or lack of evidence among meta-analyses. Methods. The quality of the included systematic reviews was assessed using the ROBIS tool. Corrected covered area (CCA) was calculated for pairs of similar meta-analyses to identify the amount of overlap. Reviews that were the most recent, comprehensive, and had adequate quality were considered for analyses when reviews showed a high overlap. In cases with a low amount of overlap among meta-analyses, all eligible studies were included. Also, citation matrices were constructed to address overlap. A network meta-analytical approach was adopted to rank different interventions. Results. Ten meta-analyses were included for quantitative synthesis. The quantitative analysis revealed that platelet-rich fibrin and its derivatives as well as ozone therapy reduce early and late pain better than the other complementary interventions compared to control (no complementary intervention). Conclusions. Despite the shortcomings of included meta-analyses, consolidated evidence suggests that platelet-rich-fibrin and its derivatives as well as ozone therapy outperform the other nonpharmacological complementary interventions in reducing early and late postsurgical pain following third molar extraction. However, the results should be interpreted with caution due to an unclear risk of bias and lack of firm evidence in the included meta-analyses. Moreover, there is a need for a standard protocol for the application of nonpharmacological complementary interventions.

Plasma rich in growth factors (PRGF) and leukocyte-platelet rich fibrin (L-PRF): comparative release of growth factors and biological effect on osteoblasts

PURPOSE

To compare the release of platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF-I) and interleukin 1β (IL-1β) of plasma rich in growth factors (PRGF) and leucocyte platelet-rich fibrin (L-PRF) and to evaluate their biological implication in osteoblasts.

METHODS

Blood from 3 healthy volunteers was processed into PRGF, immediate L-PRF (L-PRF 0') and L-PRF 30 min after collection (L-PRF-30') and a control group. Growth factors release were analyzed at 7 times by ELISA. Cell proliferation, collagen-I synthesis and alkaline phosphatase activity were assessed in primary cultures of human osteoblasts.

RESULTS

A slower controlled release of IGF-I, VEGF and PDGF was observed in the PRGF group at day 14. A higher synthesis of type I collagen was also quantified in PRGF. L-PRF released significantly higher amounts of IL-1β, that was almost absent in the PRGF.

CONCLUSIONS

The addition of leukocytes dramatically increases the secretion of proinflammatory cytokines, which are likely to negatively influence the synthesis of type I collagen and alkaline phosphatase (ALP) by osteoblasts.

A Bibliometric Analysis of Platelet-Rich Fibrin in Dentistry

Platelet-rich fibrin (PRF), a second-generation platelet concentrate, has been widely recognized in numerous studies for its performance of wound healing and regeneration in dentistry. However, bibliometric analysis of PRF in dentistry is still scarce. Thus, this study aimed to conduct and delineate a bibliometric analysis of the application of PRF and its changing trend in dentistry. All papers concerning PRF up to 30 June 2022 were included in the literature search from the Web of Science Core Collection database. These data were then entered into Microsoft Excel, analyzed by the SAS statistical software, and visualized by the VOSviewer software. A total of 562 articles were retrieved following the exclusive criteria. The results demonstrated that the trend of annual publication increased continually (p for trend < 0.01), more notably in the last five years. The majority of the articles were original (58.01%), followed by reviews (17.08%), and case reports (10.14%). The three major study designs were clinical studies (20.11%), randomized controlled trials (17.62%), and review/meta-analysis (17.08%). PRF was most frequently employed in oral surgery (31.14%), periodontal regeneration (22.42%), and implant therapy (18.68%). Turkey (16.19%), India (12.28%) and China (7.12%) were the top 3 countries publishing PRF studies. By comparing the total number of publications, total citation counts and varying counting methods, a combination of numerous counting methods was suggested for use since each counting method yields different results. Taken together, we hope with these informative findings, researchers could focus on the future direction or advancement in PRF, laying a foundation for evidence-based dentistry.

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.

Dual-Function Semaphorin 4D Released by Platelets: Suppression of Osteoblastogenesis and Promotion of Osteoclastogenesis

Effects of the antiosteoblastogenesis factor Semaphorin 4D (Sema4D), expressed by thrombin-activated platelets (TPs), on osteoblastogenesis, as well as osteoclastogenesis, were investigated in vitro. Intact platelets released both Sema4D and IGF-1. However, in response to stimulation with thrombin, platelets upregulated the release of Sema4D, but not IGF-1. Anti-Sema4D-neutralizing monoclonal antibody (mAb) upregulated TP-mediated osteoblastogenesis in MC3T3-E1 osteoblast precursors. MC3T3-E1 cells exposed to TPs induced phosphorylation of Akt and ERK further upregulated by the addition of anti-sema4D-mAb, suggesting the suppressive effects of TP-expressing Sema4D on osteoblastogenesis. On the other hand, TPs promoted RANKL-mediated osteoclastogenesis in the primary culture of bone-marrow-derived mononuclear cells (BMMCs). Among the known three receptors of Sema4D, including Plexin B1, Plexin B2 and CD72, little Plexin B2 was detected, and no Plexin B1 was detected, but a high level of CD72 mRNA was detected in RANKL-stimulated BMMCs by qPCR. Both anti-Sema4D-mAb and anti-CD72-mAb suppressed RANKL-induced osteoclast formation and bone resorptive activity, suggesting that Sema4D released by TPs promotes osteoclastogenesis via ligation to a CD72 receptor. This study demonstrated that Sema4D released by TPs suppresses osteogenic activity and promotes osteoclastogenesis, suggesting the novel property of platelets in bone-remodeling processes.

Pain Relief and Antimicrobial Activity in Alveolar Osteitis after Platelet-Rich Fibrin Application—A Non-Randomized Controlled Study

The objective was to compare pain relief in alveolar osteitis achieved by the application of platelet-rich fibrin (PRF) and aspirin cones, and to assess the influence of both treatments on bacterial concentrations in post-extraction wounds. A split-mouth, single-center, non-randomized controlled trial was conducted in 30 patients. Pain relief was assessed using the visual analog scale at three time points (before, 24 h after, and 48 h after intervention). Bacterial concentrations were evaluated from cultures of swab samples collected at the three time points. A Wilcoxon matched-pairs signed-rank test was performed to detect differences in distributions of scalar variables between treatment with PRF and aspirin cones. Pain relief at 24 h and 48 h after treatment was significantly higher (p = 0.003) with PRF application than with aspirin cone placement. Additionally, PRF application caused a significantly higher reduction in aerobic bacteria concentration, an average increase, instead of a decrease, in lactic acid bacilli concentration in the first 24 h, and a significantly greater increase in streptococci concentration at 48 h follow-up. PRF provides better pain relief than aspirin cones in alveolar osteitis. Bacterial concentrations in the extraction wounds are consistent with the pain relief achieved after PRF or aspirin application.

The use of advanced platelet-rich fibrin after surgical removal of mandibular third molars: a systematic review and meta-analysis

The objective of this systematic review was to test the hypothesis of no difference in recovery following surgical removal of mandibular third molars with the application of advanced platelet-rich fibrin (A-PRF) in the extraction socket compared with alternative biomaterials or natural wound healing. A search of MEDLINE (PubMed), Embase, Cochrane Library, and Scopus was conducted. Human randomized controlled trials published in English up until December 31, 2020 were included. Outcome measures were pain, facial swelling, trismus, soft tissue healing, alveolar osteitis, and quality of life; these were evaluated by descriptive statistics and meta-analysis including 95% confidence intervals (CI). Four studies with a low or moderate risk of bias fulfilled the inclusion criteria. A-PRF resulted in significantly lower pain scores when compared with leucocyte platelet-rich fibrin or natural wound healing after 2 days (-16.8, 95% CI -18.9 to -14.7), 3 days (-12.1, 95% CI -13.4 to -10.7), and 7 days (-1.9, 95% CI -2.9 to -0.9). A-PRF seems to have a negligible effect on facial swelling and trismus and some beneficial effect on soft tissue healing. Alveolar osteitis and quality of life were not assessed. The included studies were characterized by considerable heterogeneity and confounding variables. Thus, the level of evidence appears to be inadequate for clinical recommendations according to the focused question.

The Growth Factors in Advanced Platelet-Rich Fibrin (A-PRF) Reduce Postoperative Complications after Mandibular Third Molar Odontectomy

Surgical removal of impacted mandibular third molars constitutes one of the most frequently performed procedures within oral surgery. This surgery procedure is associated with many post-operative complications. Advanced platelet-rich fibrin (A-PRF) belongs to the second generation of platelet concentrates and is rich in numerous growth factors. The aim of this study was to assess the influence of A-PRF on selected clinical features following the surgical removal of impacted mandibular third molars. The research was conducted on 100 generally healthy patients, who underwent a lower third molar odontectomy in Department of Oral Surgery, Medical University of Gdańsk, Poland, between 2018 and 2019. The research group consisted of 50 patients (immediate A-PRF socket filling) and control group (50 patients without A-PRF socket filling). During the study, the following clinical features were assessed: pain (visual analog scale), analgesics intake, the presence of trismus, edema, hematomas within the surrounding tissues (e.g., cheek), prevalence of pyrexia, dry socket, secondary bleeding, presence of hematomas, skin warmth in the post-operative area, and bleeding time observed by the patient were analyzed on the 3rd, 7th, and 14th day after the procedure. There was a significant association between A-PRF socket filling and pain intensity, the analgesics intake, trismus, and edema on the 3rd and the 7th day (p < 0.05). The presence of hematomas and skin warmth on the 3rd day after the surgery (p < 0.05) were also statistically associated with A-PRF use. The study showed that in reducing the incidence of postoperative complications, A-PRF was more important than the position of the tooth or the duration of the procedure. The growth factors in A-PRF reduce postoperative complications, such as pain, trismus, edema, analgesics intake, presence of hematomas, and skin warmth, after mandibular wisdom teeth odontectomy.

Assessment of the Effect of A-PRF Application during the Surgical Extraction of Third Molars on Healing and the Concentration of C-Reactive Protein

Extraction procedures for mandibular third molars are performed all over the world every day. Local inflammation resulting from surgery, and the pain that patients experience, often make it impossible to take up daily life activities, such as work or sports. Growth and anti-inflammatory factors, located in the fibrin network, have a positive effect on tissue-healing processes and should also reduce local inflammation. Advanced platelet-rich fibrin (A-PRF) applied locally influences such processes as: angiogenesis, osteogenesis and collagenogenesis. It also affects mesenchymal cell lines and anti- and pro-inflammatory mediators. Due to the autologous origin of the material, their use in guide bone regeneration (GBR) is more and more widespread in dentistry. The results of previous studies indicate that the use of A-PRF in the treatment area significantly reduces postoperative pain, while the formation of edema is not affected. C-reactive protein (CRP), which is an acute phase protein, appears in the blood as a consequence of inflammation. Due to the dynamics of changes in concentration of CRP, it is a protein that is sufficiently sensitive and is used in studies to monitor the tissue healing process. The effect of A-PRF application on CRP concentrations, before and after surgery, has not been investigated yet. The study was conducted on 60 generally healthy patients. A faster decrease of CRP levels was shown in patients who used A-PRF after the procedure. Additionally, it accelerated healing and reduced the occurrence of a dry socket close to 0.

Differences in platelet-rich plasma composition influence bone healing

AIM

Platelet-rich plasma (PRP) is an autologous blood-derived material that has been used to enhance bone regeneration. Clinical studies, however, reported inconsistent outcomes. This study aimed to assess the effect of changes in leucocyte and PRP (L-PRP) composition on bone defect healing.

MATERIALS AND METHODS

L-PRPs were prepared using different centrifugation methods and their regenerative potential was assessed in an in-vivo rat model. Bilateral critical-size tibial bone defects were created and filled with single-spin L-PRP, double-spin L-PRP, or filtered L-PRP. Empty defects and defects treated with collagen scaffolds served as controls. Rats were euthanized after 2 weeks, and their tibias were collected and analysed using micro-CT and histology.

RESULTS

Double-spin L-PRP contained higher concentrations of platelets than single-spin L-PRP and filtered L-PRP. Filtration of single-spin L-PRP resulted in lower concentrations of minerals and metabolites. In vivo, double-spin L-PRP improved bone healing by significantly reducing the size of bone defects (1.08 ± 0.2 mm³ ) compared to single-spin L-PRP (1.42 ± 0.27 mm³ ) or filtered L-PRP (1.38 ± 0.28 mm³ ). There were fewer mast cells, lymphocytes, and macrophages in defects treated with double-spin L-PRP than in those treated with single-spin or filtered L-PRP.

CONCLUSION

The preparation method of L-PRP affects their composition and potential to regenerate bone.

Photobiomodulation therapy reduces postoperative pain after third molar extractions: A randomized clinical trial

Background

To assess the efficacy of PBMT on reducing postoperative pain scores in patients submitted to third molar extractions.

Material and Methods

A randomized controlled trial (ReBEC:RBR-94BCKZ) was designed according to the SPIRIT and followed the CONSORT. Patients were randomly allocated according to control or PBMT groups. PBMT consisted of the application of GaAlAs laser (808nm;50mW) applied in six points (1.23 min;11 J/cm2) after extraction. Pain scores were assessed using the Visual Analogue Scale (VAS) in millimeters evaluated after 6 (T6), 24 (T24), and 48 (T48) hours. The Wilcoxon Mann–Whitney test was used to check for possible associations between VAS scores and treatment groups.

Results

A total of 101 third molar extractions were performed in 44 patients. The mean age was 28 years old(SD±11.54). Comparing control and intervention, PBMT group showed a significant effect on the reduction of postoperative pain at T6(mean VAS=0.9; C.I:0.63–1.16) compared to control (mean VAS=2.5;C.I:2.1–2.88)(p<0.001). The same statistically significant effect on the reduction of postoperative pain was observed at T24 (PBMT mean VAS=0.72;C.I:0.51–0.93; control mean VAS=2.86;C.I:2.40–3.31;p<0.001) and T48 (PBMT mean VAS=0.64;C.I:0.36–0.92; control mean VAS=2.86;C.I:2.37–3.34;p<0.001).

Conclusions

PBMT significantly reduce the postoperative pain scores when assessed 6, 24, and 48 hours after third molar extractions.

Key words:Controlled clinical trial, gallium aluminium arsenide lasers, third molar.

Third molar surgery: Past, present, and the future

Third molar surgery is the most common ambulatory procedure done by oral and maxillofacial surgeons. Surgical approaches for the removal of third molars have been published since the 20th century. This article reviews the history and development of extraction techniques through a literature review. The literature was selected through a search of an electronic database. Key words for the Medline search were "mandibular/maxillary third molar," "impacted mandibular/maxillary third molar," "mandibular/maxillary third molar flap design," and "mandibular/maxillary third molar incision." The search was restricted to English-language articles. Additionally, a manual search in the major oral surgery journals and books was performed. The aim of this article is to examine the evolution of third molar surgery, recognize pioneering techniques, and compare these techniques to current approaches. Common approaches employed today are discussed and treatment philosophies with thoughts for future therapies are provided.

Efficacy of Sticky Bone as a Novel Autologous Graft for Mandibular Third Molar Extraction Socket Healing - An Evaluative Study

Introduction

Recently, initiation and enhancement of extraction socket healing has been amplified by platelet concentrates, whereas the positive role of Sticky bone has been focused on maintaining alveolar bone dimensions. This study aimed to determine the effectiveness of Sticky Bone for socket grafting of mandibular third molars (M3Ms) in terms of soft- and hard-tissue healing.

Materials and Methods

This split-mouth prospective trial constituted prophylactic removal of M3Ms with Sticky bone grafted in the study site as a primary predictor variable. Patients underwent 3 months of mandatory follow-up where pain, swelling, interincisal mouth opening, and gingival healing were measured on the 3^rd, 7^th, and 14^th day using the Numeric Rating Scale, anatomic landmarks, steel metric ruler, and criteria given by Landry et al. respectively. Radiological healing was calculated based on the height of the socket, Kelly's Index, and histogram values immediately after the procedure at 1 week, 1 month, and 3 months, respectively. Statistical comparison was made using Paired t-test. P < 0.05 was considered significant.

Results

Forty-seven patients (mean 26.83 ± 6.58 years) demonstrated significantly lesser pain, swelling, and better gingival healing at the study site on multiple periods of follow-up. Rapid bone formation with superior density, lesser alveolar resorption, earlier bone blending, and trabecular formation were noticed on the study site with a significant difference at all time intervals.

Discussion

Sticky bone was chosen as the graft owing to advantages such as simple preparation, convenient handling characteristics, safety, evident postoperative patient comfort, better retention of the clot, enhanced soft-tissue healing, absence of infection, and decreased osseous deformation as compared to the control site. This study validated the role of Sticky bone as an indispensable component of regenerative therapy in the orofacial osseous tissues as it was an ideal biologic graft with fibrin rich structure.

Conclusion

This study validated the role of Sticky bone as an indispensable component of regenerative therapy in the orofacial osseous tissues as it was an ideal biologic graft with fibrin rich structure.

Leukocyte and Platelet-Rich Fibrin Have Same Effect as Blood Clot in the 3-Dimensional Alveolar Ridge Preservation. A Split-Mouth Randomized Clinical Trial

PURPOSE

Leukocyte- and platelet-rich fibrin (L-PRF) has been used for alveolar ridge preservation (ARP) in postextraction tooth sockets. However, current reports have measured its effectiveness in linear measurements of 3-dimensional ridge preservation. The purpose of this study was to determine the effectiveness of the use of L-PRF filling versus natural clot blood healing in ARP according to the clinical, radiographic, and volumetric measurements of postextraction tooth sockets.

MATERIALS AND METHODS

A split-mouth randomized clinical trial was designed. Healthy patients who needed bilateral extraction of upper third molars were selected. After the tooth extraction, the socket was filled and distributed randomly with L-PRF and the contralateral socket only with the blood clot. The dimensional change of soft tissue healing around the sockets, and the length, depth, and difference of bone formation were examined using standardized periapical radiographs. Volumetric measurement variation of the sockets was evaluated by 3-dimensional scanning of dental casts. Changes of all measures were analyzed at 7 days (initial) and 3 months (final) after the tooth extraction and compared between both groups (t test; P < .05).

RESULTS

Sixteen patients (aged 24.75 ± 3.53 years; 56.25% women) participated. Measurements of wound healing and the length, depth, and difference of bone formation were similar for both study groups at initial and final times. The calculation of initial-final volumetric socket variation was 15.45 ± 13.12 μL using L-PRF and 14.12 ± 11.23 μL using blood clot (P = .78).

CONCLUSIONS

L-PRF filling showed the same dimensional and volumetric behavior as normal blood clot healing in the ARP of postextraction tooth sockets. Future investigations will have to analyze the use of surgical models and digital instruments in ARP techniques.

Effect of platelet-rich fibrin on the control of alveolar osteitis, pain, trismus, soft tissue healing, and swelling following mandibular third molar surgery: an updated systematic review and meta-analysis

The purpose of this study was to estimate the effect of platelet-rich fibrin (PRF) on the control of alveolar osteitis (AO), pain, trismus, soft tissue healing, and swelling following mandibular third molar surgery. A comprehensive search of the literature was conducted through PubMed, Embase, Web of Science, and Cochrane Library up to May 2019. Randomized controlled studies conforming to the inclusion criteria were included. The record screening and data extraction were conducted by two authors independently. The risk of bias assessment was performed according to the guidelines recommended by the Cochrane Collaboration. The quantitative analysis was performed using RevMan version 5.3. Nineteen studies were included in the systematic review and 17 studies were eligible for the meta-analysis. The use of PRF significantly reduced the incidence of AO and postoperative pain when compared to the controls (AO: relative risk 0.43, 95% confidence interval (CI) 0.28 to 0.65, Z=3.90, P<0.0001 (I²=0%); pain: day 1, standardized mean difference (SMD) -1.12, 95% CI -1.87 to -0.37, Z=2.93, P=0.003 (I²=95%); day 3, SMD -0.93, 95% CI -1.48 to -0.38, Z=3.30, P=0.001 (I²=92%); day 7, SMD -1.84, 95% CI -2.98 to -0.71, Z=3.19, P=0.001 (I²=97%)). Additionally, the result showed a better soft tissue healing when PRF was used (mean difference -0.63, 95% CI -1.08 to -0.18, Z=2.76, P=0.006 (I²=90%)). The use of PRF reduced the incidence of AO and postoperative pain following third molar surgery. Furthermore, PRF may also improve the postoperative soft tissue healing.

Efficacy of concentrated growth factors combined with mineralized collagen on quality of life and bone reconstruction of guided bone regeneration

To evaluate the clinical efficacy of concentrated growth factors (CGFs) combined with mineralized collagen (MC) in guided bone regeneration (GBR). A retrospective study involving 29 patients treated with GBR technique, which was performed either CGF and MC complexes or MC alone. Implants were inserted simultaneously and cone-beam computed tomography was taken immediately, at 3 and 6 months postoperation. Questionnaires were completed by all patients so as to evaluate the main symptoms and daily activities during the first week after surgery. The outcomes of the two groups were statistically compared. All implants healed uneventfully. Patients in both groups suffered from different levels of discomfort for the reason of swelling, pain and chewing impairment on 1–2 days. Meanwhile, swelling of the Trial group was weaker than the Control group. When compared with the Control group, pain levels in Trial group were more rapidly reduced and patients took fewer analgesics from Day 3. Furthermore, the reconstitution mean value of the graft was thicker at 3 and 6 months in Trial group. CGFs complex with MC were beneficial to relieve the clinical symptoms, promote the peri-implant bone regeneration and shorten the healing time.

Effect of concentrated growth factors on frequency of alveolar Osteitis following partially-erupted mandibular third molar surgery: a randomized controlled clinical study

Background

The aim of this prospective study was to assess the effectiveness of concentrated growth factors (CGF) in preventing the development of alveolar osteitis (AO) after the extraction of partially-erupted mandibular third molars.

Methods

Seventy patients (26 men and 44 women) 18 years or older (mean age 25.86; range 18–35) underwent 140 third molar extractions. All the patients presented with bilateral, partially-erupted mandibular third molars and underwent surgical extractions. In each case, one socket received CGF and the other served as a control. The predictor variable was the CGF application and the sides were categorized as ‘CGF’ and ‘non-CGF’. The outcome variable was the development of AO during the first postoperative week. Other study variables included age and gender. Data were analyzed using Cochran’s Q test with the significance level set at a P value less than 0.05.

Results

The overall frequency of AO was 11.4% for the control group. The frequency of AO in the CGF group was significantly lower than in the non-CGF group (p < 0.001).

Conclusions

Based on the results of this study, application of CGF fibrin gel may decrease the risk of AO development after mandibular third molar surgery.

Trial registration

This study was registered in ClinicalTrials.gov database on November 1, 2019 (ID: NCT04151147, retrospectively registered).

A new insight of Platelet-Rich Fibrin clots morphology and their elemental composition

This study analyzed the architecture of Platelet-Rich Fibrin (PRF) clots and assessed their elemental composition in order to provide new insight into this biomaterial. Five surplus PRF clots (2,700 RPM, 12 min.) donated by patients (63.6 ± 12.3 years old) were prepared for use in dental clinical procedures. The internal three-dimensional morphology of the red zones and the thirds of the yellow zones of the clots were analyzed by Variable Pressure Scanning Electron Microscope (VPSEM) after sample preparation by two methods: 1. Fixation (2.5% gluataraldehyde); and 2. Fixation with subsequent partial removal of extracellular elements (8 N, HCl). Semi-quantitative elemental analysis was performed by energy-dispersive X-ray spectrometry (EDX). VPSEM analysis showed erythrocytes in both the red zone and the yellow zone, which consisted mainly of fibrin. Removal of extracellular elements enriched the morphology of both zones; the organization of the fibrin was observed to differ in the thirds of the yellow zone, with increasing density and organization to distal. The elements that compose organic substances (C-Carbon, N-Nitrogen, O-Oxygen, Na-Sodium and P-Phosphorus) and halogens (Cl-Chloride and S-Sulfur) were detected; the highest concentrations were of C, followed by O (p < 0.05), in the proximal region of the fibrin. The results of the present study suggest organization of fibrin in the PRF clot, and also reveal the distribution of the elements present in the different regions of the clot. Improved understanding of these characteristics may favor the use of this biomaterial by increasing its efficiency and functionality.

Platelet Concentrate Treatments for Temporomandibular Disorders: A Systematic Review and Meta-analysis

OBJECTIVES

This systematic review compared platelet concentrates (PCs) versus hyaluronic acid (HA) or saline/Ringer's solution injections as treatments of temporomandibular osteoarthritis and disc displacement in terms of pain and maximum mouth opening (MMO).

METHODS

PubMed, Cochrane, and Scopus were searched up to March 6, 2020. Inclusion criteria were randomized clinical trials (RCTs). Exclusion criteria were case series, observational studies, animal studies, and reviews. The Effective Public Health Practice Project (EPHPP) quality assessment tool was used to assess the risk of bias in the included studies. The weighted mean difference was used to compare the results.

RESULTS

Nine RCTs were included with a total of 407 patients. The numbers of joints treated were 262, 112, and 112 in the PC, HA, and saline groups, respectively. The quality of studies was rated as strong in 4 studies, moderate in 4 studies, and weak in 1 study. The meta-analysis revealed that PCs decreased pain visual analogue scale (VAS) scores compared to HA by an average of -1.11 (CI, -1.62 to -0.60; P < 0.0001) and -0.57 (CI, -1.55 to 0.41; P = 0.26) at 3 and 12 mo follow-up respectively. Also, the average decrease in pain scores with PC compared to saline was -1.33 (CI, -2.61 to -0.06; P = 0.04), -2.07 (CI, -3.46 to -0.69; P = 0.003), and -2.71 (CI, -4.69 to -0.72; P = 0.008) at 3, 6, and 12 mo, respectively. Regarding MMO measurements, PC was comparable to HA, but it was significantly better than saline after 3 and 6 mo [2.9 mm (CI,1.47 to 4.3; P < 0.0001), and 1.69 mm (CI, 0.13 to 3.25; P = 0.03) respectively].

CONCLUSION

PC reduces pain VAS scores compared to HA during the first 3 m after treatment, and when compared to saline, it reduces pain and increases MMO for longer durations. However, due to differences between groups regarding PC preparation protocols and study heterogeneity, further standardized RCTs are required.

KNOWLEDGE TRANSFER STATEMENT

This study provides researchers and clinicians with quantitative and qualitative analyses of the current evidence regarding the clinical outcomes of platelet concentrate injections in the treatment of temporomandibular joint osteoarthritis and disc displacement in terms of pain control and maximum mouth opening.

The use of leukocyte- and platelet-rich fibrin in the management of soft tissue healing and pain in post-extraction sockets: A randomized clinical trial

This study aimed to evaluate the clinical effect of leukocyte- and platelet-rich fibrin (L-PRF) to improve epithelialization and decrease postoperative pain in post-extraction sockets. Thirty two participants requiring extractions of posterior teeth were randomized into two groups: 1) extractions and socket filling with L-PRF membrane (test group) and 2) extraction with spontaneous healing (control group). One week after extraction, an assessment of soft tissue healing around the sockets was performed using the healing index. Also, postoperative pain by visual analog scale (VAS) and number of consumed analgesic tablets were recorded. In the first week, the sockets of the test group presented a significantly (mean of 3.81 ± 0.54; p = 0.0138) higher level of healing when compared to the sockets of the control group (mean of 3.18 ± 0.65). The participants of control group reported a significantly (mean of 5.12 ± 1.08; p = 0.0128) higher level of postoperative pain when compared to the test group (mean of 4 ± 1.15). Also, the control group consumed a greater number of analgesics (mean of 1.75 ± 0.85; p = 0.0136) when compared to the test group (mean of 1 ± 1.15). The results of the present study demonstrate that whenever improved healing of the extraction socket is needed, the use of L-PRF should be considered. In addition, the use of L-PRF decreases postoperative pain and discomfort.

Reduction in post extraction waiting period for dental implant patients using plasma rich in growth factors: an in vivo study using cone-beam computed tomography

Objectives

This study examined the effects of plasma-rich growth factors (PRGF) on accelerating bone regeneration/repair in fresh extraction sockets, and determined the quality and quantity of bone by assessing the bone density using cone-beam computed tomography (CBCT).

Materials and Methods

Twenty patients, who had undergone bilateral extractions, were included in this study. In one extraction socket, PRGF was used and covered with an autologous fibrin plug. Nothing was used in the opposite side extraction socket. Thirteen weeks post extraction, the level of bone regeneration was evaluated on both sides with CBCT.

Results

At the end of the study, the mean bone density according to the Hounsfield units (HU) in the control group and PRGF group was 500.05 HU (type III bone type) and 647.95 HU (type II bone type), respectively.

Conclusion

This study recommends the use of PRGF in post extraction sites to accelerate the rate of bone regeneration and improve the quality of regenerated bone. The technique to process PRGF was simple compared to previously mentioned techniques used for platelet-rich plasma (PRP) preparation. PRP preparation requires a two-cycle centrifugation procedure, leading to a longer processing time.

Use of Platelet-Rich Plasma and Platelet-Rich Fibrin in Dentistry and Oral Surgery: Introduction and Review of the Literature

Platelet concentrates, mostly represented by platelet-rich plasma and platelet-rich fibrin, have gained significant interest in various medical and oral disciplines because of their potential to stimulate and boost regeneration of hard and soft tissues. Prepared from the patient’s own blood, they have been tested and used in various different surgical fields including oral and maxillofacial surgery. The effects of these biomaterials are described to be a result of the large concentration of platelets which contain a wide range of growth factors. The aim of this article is to introduce the principle and function of these platelet concentrates, to review their preparation, and to provide a comprehensive examination of the published oral and maxillofacial literature on this subject.

Regenerative Effect of Platelet Concentrates in Oral and Craniofacial Regeneration

Platelet concentrates (PCs) are biological autologous products derived from the patient's whole blood and consist mainly of supraphysiologic concentration of platelets and growth factors (GFs). These GFs have anti-inflammatory and healing enhancing properties. Overall, PCs seem to enhance bone and soft tissue healing in alveolar ridge augmentation, periodontal surgery, socket preservation, implant surgery, endodontic regeneration, sinus augmentation, bisphosphonate related osteonecrosis of the jaw (BRONJ), osteoradionecrosis, closure of oroantral communication (OAC), and oral ulcers. On the other hand, no effect was reported for gingival recession and guided tissue regeneration (GTR) procedures. Also, PCs could reduce pain and inflammatory complications in temporomandibular disorders (TMDs), oral ulcers, and extraction sockets. However, these effects have been clinically inconsistent across the literature. Differences in study designs and types of PCs used with variable concentration of platelets, GFs, and leucocytes, as well as different application forms and techniques could explain these contradictory results. This study aims to review the clinical applications of PCs in oral and craniofacial tissue regeneration and the role of their molecular components in tissue healing.

Usefulness of platelet-rich fibrin as a hemostatic agent after dental extractions in patients receiving anticoagulant therapy with factor Xa inhibitors: a case series

PURPOSE

To evaluate the clinical outcomes of platelet-rich fibrin (PRF) application for hemostasis after dental extraction in patients receiving anticoagulant therapy with factor Xa inhibitors.

METHODS

In total, 25 patients receiving anticoagulant therapy with rivaroxaban or apixaban who required routine dental extraction were evaluated. In all patients, PRF was used for hemostasis in addition to adapting sutures. Bleeding was subjectively assessed using a sterilize gauze pad at 24, 48, and 72 h after the procedure.

RESULTS

All invited participants (n = 25) consented to participate. The PRF clots successfully arrested bleeding after extraction in all patients, with no complications at any time point after the procedure. Favorable soft tissue healing was observed during suture removal at 10 days after the procedure in all patients, with no signs of infection or late healing.

CONCLUSIONS

The results of this case series indicate that PRF is a promising natural hemostatic agent for the management of bleeding after dental extraction in patients receiving factor Xa inhibitor therapy. Further controlled clinical studies with larger patient samples are necessary to clarify the findings of this case series.

Platelet-rich fibrin and collagen membrane in the preservation of the alveolar bone: Feasibility of the elemental inorganic composition and scanning electron microscopy analysis

The success of dental implants is related to the amount, quality, and composition of the alveolar bone. The placement of platelet-rich fibrin (PRF) clot associated with a resorbable collagen membrane (RCM) in a postextraction alveolus is a technique used for ridge preservation. This case report study analyzed the ultrastructural characteristics of cross-sectioned alveolar bone that received PRF and RCM using scanning electron microscopy and the inorganic composition using "energy dispersive X-ray spectrometry," in order to explore the feasibility of this method to clinical studies. Three alveolar bone samples from two male patients (37 and 58 years old), obtained in the procedure of placing the dental implant, were analyzed. Two bone samples previously received PRF and RCM (M37 and M58), the third sample represented a physiological bone formation without treatment (M37-control). The bone sample M37 showed irregularly shaped islets of calcified material intermingled with connective tissue. The other samples, from the 58-year-old patient with PRF and RCM (M58); and the other untreated bone sample from the same 37-year-old patient (M37-control) showed similar ultrastructural morphology with trabecular conformation without islets agglomerations. The inorganic composition analysis showed higher concentrations of calcium and phosphorus in both samples treated with PRF and RCM in comparison to the untreated bone sample. The Ca/P ratio was higher in the M37 sample compared to the others samples. The results showed morphology and inorganic composition differences among the treatments used, suggesting that this method is feasible to analyze parameters of the alveolar bone tissue.

Effects of leukocyte- and platelet-rich fibrin associated or not with bovine bone graft on the healing of bone defects in rats with osteoporosis induced by ovariectomy

OBJECTIVE

To evaluate the healing of critical size defects (CSDs) in calvaria of rats with osteoporosis induced by ovariectomy and treated with leukocyte- and platelet-rich fibrin (L-PRF) associated or not with bovine bone graft (XENO).

MATERIAL AND METHODS

A total of 32 rats underwent a bilateral ovariectomy procedure. After 3 months, one 5 mm in diameter CSD was created in the middle of the calvaria of each animal. In group C, defect was filled with blood clot only. In PRF, XENO, and PRF-XENO groups, defects were filled with 0.1 ml of L-PRF, 0.1 ml of XENO, and a mixture of 0.1 ml of L-PRF plus 0.1 ml of XENO, respectively. L-PRF compressed clots were used to cover the defects in PRF and PRF-XENO groups. Animals were submitted to euthanasia at 30 postoperative days. Histomorphometric, microtomographic, and immunohistochemical analyses were performed.

RESULTS

PRF-XENO group presented greater amount of neoformed bone (NB) when compared with XENO group, as well as higher expression of vascular endothelial growth factor (VEGF), osteocalcin (OCN), and bone morphogenetic protein (BMP-2/4) (p < .05). PRF group presented increased amount of NB and higher expression of VEGF, OCN, BMP-2/4, and Runt-related transcription factor 2 (RUNX-2) when compared with group C (p < .05).

CONCLUSIONS

(a) The isolated use of L-PRF clot can improve bone neoformation in CSDs in rats with osteoporosis induced by ovariectomy, but seems to lead to decreased amount of bone neoformation when compared to the isolated use of XENO; (b) L-PRF potentiates the healing of XENO in rats with osteoporosis induced by ovariectomy.

Impact of platelet-rich fibrin on mandibular third molar surgery recovery: a systematic review and meta-analysis

Background

The present study investigated and evaluated the efficacy and safety of platelet-rich fibrin (PRF) in patients during bilateral mandibular third molars extraction by systematic review and meta-analysis.

Methods

The PubMed, Embase, and Cochrane library databases were retrieved, and the effect of PRF on the healing process of the alveolar socket after surgical extraction of the mandibular third molars was evaluated by meta-analysis. The postoperative pain, swelling, trismus, osteoblastic activity, and soft tissue healing were assessed, and the incidence of alveolar osteitis, weighted mean difference (WMD)/standard mean difference (SMD), the risk ratio (RR), and the 95% confidence interval (CI) were calculated.

Results

The current results showed that the local application of PRF during lower third molar extraction prevented postoperative complications. Subsequently, the pain (SMD = − 0.53, 95% CI: − 1.02–-0.05, P_{heterogeneity} = 0.001, I² = 75.7%) and swelling (WMD = − 0.55, 95% CI: − 1.08–-0.01, P_{heterogeneity} = 0.573, I² = 0) were relieved and the incidence of alveolar osteitis was reduced (RR = 0.35, 95% CI: 0.16–0.75, P_{heterogeneity} = 0.597, I² = 0%). However, no significant difference was observed in trismus, osteoblastic activity, and soft tissue healing between the PRF and non-PRF groups.

Conclusion

The current study confirms that PRF only reduces some of the postoperative complications but does not prevent all the postoperative complications. PRF significantly relieved the pain and swelling and reduced the incidence of alveolar osteitis after the extraction of an impacted lower third molar.

Electronic supplementary material

The online version of this article (10.1186/s12903-019-0824-3) contains supplementary material, which is available to authorized users.

The use of platelet-rich fibrin to enhance the outcomes of implant therapy: A systematic review

Objective

To assess the impact of platelet‐rich fibrin (PRF) on implant dentistry. The primary focused question was as follows: What are the clinical, histological, and radiographic outcomes of PRF administration for bone regeneration and implant therapy?

Method

A systematic literature search comprised three databases: MEDLINE, EMBASE, and Cochrane followed by a hand search of relevant scientific journals. Human studies using PRF for bone regeneration and implant therapy were considered and articles published up to December 31, 2017 were included. Eligible studies were selected based on the inclusion criteria. Randomized controlled trials (RCT) and controlled clinical trials (CCT) were included.

Results

In total, 5,963 titles were identified with the search terms and by hand search. A total of 12 randomized controlled trials (RCT) met the inclusion criteria and were chosen for data extraction. Included studies focused on alveolar ridge preservation after tooth extraction, osseointegration process, soft tissue management, bone augmentation, bone regeneration after sinus floor elevation and surgical peri‐implantitis treatment. Overall, the risk of bias was moderate or unclear. Nine studies showed superior outcomes for PRF for any of the evaluated variables, such as ridge dimension, bone regeneration, osseointegration process, soft tissue healing. Three studies failed to show any beneficial effects of PRF. No meta‐analysis could be performed due to the heterogeneity of study designs.

Conclusions

There is moderate evidence supporting the clinical benefit of PRF on ridge preservation and in the early phase of osseointegration. It remains unclear whether PRF can reduce pain and improve soft tissue healing. More research support is necessary to comment on the role of PRF to improve other implant therapy outcomes.

An on-site preparable, novel bone-grafting complex consisting of human platelet-rich fibrin and porous particles made of a recombinant collagen-like protein

Platelet‐rich fibrin (PRF) is widely used in regenerative medicine. Nonetheless, major issues include its controversial effects on bone regeneration and a lack of quality‐assured glass tubes required for coagulation. We used porous particles (FBG) comprising a recombinant RGD motif‐enriched collagen I‐like protein to activate the coagulation pathway and examined the effects of the resulting PRF–FBG complex on bone regeneration. Human whole‐blood samples were mixed with FBG in plastic tubes and centrifuged to prepare a PRF–FBG complex. Platelet‐derived growth factor‐BB (PDGF‐BB) levels and cell growth activity were determined by ELISA and a bioassay using osteoblasts. Bone regenerative activity was assessed using a mouse model of calvarial bone defect. FBG facilitated PRF‐like matrix formation during centrifugation. In this PRF–FBG complex, the microstructure of fibrin fibers was similar to that of PRF prepared conventionally in glass tubes. PDGF‐BB levels and mitogenic action were not significantly influenced by FBG. In the bone defect model, although PRF did not exert any significant positive effects on its own, in combination with FBG, it synergistically stimulated new bone formation. This study demonstrated that incorporation of FBG into whole‐blood samples induces PRF formation without the aid of glass tubes. The resulting PRF–FBG complex could be a promising bone grafting material in clinical settings. © 2018 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1420–1430, 2019.

Platelet-rich fibrin in oral surgical procedures: a systematic review and meta-analysis

The effect of platelet-rich fibrin (PRF) in enhancing the healing after oral surgical interventions is still a matter of debate. The purpose of this study was to identify instances where PRF has been shown to be effective in oral surgical procedures. A comprehensive literature search was performed up to 2017 on PubMed/MEDLINE, Cochrane Library, Web of Science, Scopus and LILACS databases and grey literature. The full-text of potentially relevant studies were reviewed and only randomized clinical trials (RCTs) were included. A total of 559 studies were found, of which 30 were included for qualitative analysis and 13 for quantitative analysis. Three review authors assessed the risk of bias independently. The available literature suggests that PRF has a positive effect in improving alveolar preservation on extraction sockets and around dental implants. The qualitative analysis showed a significantly better effect of PRF in promoting bone regeneration for alveolar cleft reconstruction. The meta-analysis for third molar surgery showed a decrease in prevalence of alveolar osteitis. PRF increased implant stability 1 week and 1 month after surgery (P=0.0005 and 0.0003). Due to the lack of studies with low risk of bias and a limited number of patients available, further RCTs are needed to confirm these results.

Delayed Socket Healing After Dental Extraction in Patients Undergoing Myelosuppressive Chemotherapy for Hematological Malignancy: Incidence and Risk Factors

PURPOSE

The purpose of this study was to measure the frequency and identify factors associated with delayed socket healing after dental extraction in patients undergoing myelosuppressive chemotherapy for hematologic malignancy.

MATERIALS AND METHODS

This prospective cohort study focused on delayed healing after extraction in patients with hematologic malignancy. Sockets with delayed healing were defined as those with intense pain and bone exposure 1 week postoperatively. Patients with and without delayed socket healing were compared using the Fisher exact test and Mann-Whitney U test with some variables. Receiver operating characteristics curve analysis was conducted to define cutoff values for delayed healing.

RESULTS

One hundred ninety-four dental extractions in 93 patients (median age, 64 yr; range, 20 to 85 yr) were analyzed. The incidence of delayed socket healing was 7.5% (7 of 93 patients). There was no postoperative bleeding. Older age, type of hematologic malignancy (acute leukemia), shorter time from dental extraction to initiation of chemotherapy, low platelet count or hemoglobin level, requirement for red blood cell concentrate or platelet transfusion, and use of an absorbable hemostatic agent were statistically associated with the occurrence of delayed socket healing. Platelet and hemoglobin cutoffs were 4.6 × 10⁴/μL and 7.7 g/dL, respectively.

CONCLUSIONS

Although dental extraction can be safely performed in patients undergoing myelosuppressive chemotherapy for hematologic malignancy, oral surgeons should understand the potential risk for delayed socket healing. When considering dental extraction, patients with hematologic malignancy and low hemoglobin or platelet levels should be informed about the possibility of delayed socket healing.

Efficacy of platelet concentrates in pulpotomy - a systematic review

The main purpose of the present systematic review was to evaluate the efficacy of platelet concentrates in pulpotomy of human teeth. Our systematic search included Medline, Embase, CINAHL, PsycINFO, Scopus, key journals, and review articles; the date of the last search was July 30, 2017. We graded the methodological quality of the studies by Cochrane Risk of Bias tool. Four randomized controlled trails were included in the present systematic review. The number of study participants ranged from 28 to 50, with a mean of 45.5. The age of study participants ranged between 4 and 25 years. In three of the included studies, platelet-rich fibrin (autologous) was used and in one study lyophilized freeze-dried platelet (allogenic) was used as pulpotomy material. Calcium hydroxide and mineral trioxide aggregate were used in control groups. The quality assessment rated three studies as being of fair quality and one study as poor quality. Two of the included studies showed a 100% success of pulpotomy with platelet concentrates and two studies showed more than 80% of success, but the difference between control group and platelet concentrates group was not statistically significant. To conclude, the number of publications that met all inclusion criteria was found to be very limited and no significant difference was reported in the studies comparing platelet concentrates with other materials in pulpotomy. The present results point to the need for high-quality randomized controlled trials in further research.