Role of platelet rich fibrin and platelet rich plasma in wound healing of extracted third molar sockets: a comparative study

Er:YAG Laser Therapy on Alveolar Osteitis After Mandibular Third Molar Surgery: A Randomized Controlled Clinical Study

Background: Alveolar osteitis (AO) or "dry socket" affects the quality of life of patients, and there is a high clinical demand for its effective treatment. Objective: To evaluate the effect of Er:YAG laser therapy (ErLT) on AO after mandibular third molar surgery. Methods: Eighty-three patients were randomly divided into Er (n = 43) and control groups (n = 40). In the Er group, the Er:YAG laser (2940 nm; AT Fidelis Fotona, Ljubljana, Slovenia) was used to irradiate the AO site directly in micro short-pulsed mode (pulse duration 0.1 ms, pulse energy 100 mJ, frequency 40 Hz, water 4, and air 2) until all debris and necrotic material had been removed, exposing fresh bone and soft tissue surfaces with blood exudation. The control group received mechanical therapy until the treated lesions resembled those in the Er group. Pain assessment was performed at baseline and on days 1-7 post-intervention using the visual analog scale (VAS). Wound healing was assessed using the wound healing index (WHI). The operating times of the two therapies were also recorded. Results: Group Er had lower VAS scores than the control group on days 1-3 (p = 0.00). There was no significant difference between the two groups on days 4-7 (p = 0.15). The WHI scores were better in the Er group than those in the control group (t = 2.65, p = 0.01), especially in terms of redness (t = 2.70, p = 0.01). There was no significant difference in the operating time between the two groups (t = 0.76, p = 0.45). Conclusions: Compared with mechanical therapy, ErLT for AO provides rapid pain relief and improved wound healing.

The Effectiveness of Autologous Platelet Concentrates in the Clinical and Radiographic Healing after Endodontic Surgery: A Systematic Review

Regenerative techniques are increasingly applied in endodontic surgery, but different materials may have varying impacts on soft and hard tissue healing. This systematic review aims to evaluate the effectiveness of autologous platelet concentrates (APCs) in clinical and radiographic healing after endodontic surgery. The data for this systematic review were processed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for improving the reporting of systematic reviews and meta-analyses. A literature search was conducted until October 2023 on PubMed, Scopus, and Cochrane Databases. Randomized controlled trials and controlled clinical trials addressing the use of APCs in patients who presented persistent periapical lesions and needed periapical surgery were included. Dual publications, narrative reviews, systematic reviews, case series, questionnaires, animal studies, case reports, letters to the editor, in vitro studies, and abstracts were excluded. In total, the search resulted in 14 papers. Clinical and radiographical findings were reported, showing that when APCs were used, patients exhibited less pain and swelling and a greater reduction of apical radiolucency after 12 months follow-up on average. However, the moderate/high risk of bias of included studies and their high heterogeneity, do not allow one to draw definitive conclusions on the effectiveness of APC after endodontic surgery.

Evaluation of bone repair with platelet-rich fibrin following the extraction of impacted third molars - randomized clinical trial

BACKGROUND

The aim of the present study was to evaluate postoperative effects of platelet-rich fibrin (PRF) in wound and bone healing, pain, swelling and periodontal complications outcomes after impacted third molars extraction.

MATERIAL AND METHODS

A prospective, randomized, split-mouth, double-blind clinical trial was conducted. PRF was placed within sockets following tooth removal and before suturing mucoperiosteal flap while no treatment was performed on control group's sockets. Patients were evaluated considering bone volume which was obtained in the 90-day postoperative period. Other variables included trabecular thickness, trabecular distance and grey values, pain, swelling, and wound healing. A Wilcoxon test and a t-Student test were used at a 5% significance level and a Friedman test was used to multiple comparisons.

RESULTS

Forty-four surgeries were performed in the present study. The patients' mean age was 22.41 (± 2.75 years) and 72.73% were women. PRF was associated to increased trabecular thickness and bone volume means (p < 0.001). The experimental group had significantly lower pain scores at 4h, 6h, 8h, 16h, 24h, and 72h (p ˂ 0.05). Mean swelling was lower on the experimental group (p < 0.001). The PRF group showed significant higher wound healing (p ˂ 0.001).

CONCLUSIONS

Alveolar filling with PRF improves wound and bone healing after extractions while also decreasing pain and swelling in the postoperative period.

The Effect of Local Melatonin Application Following the Removal of an Impacted Mandibular Third Molar

PURPOSE

Pain, swelling, limitation of the mouth opening, development of intra-bony defects, and bone loss are common side effects of removing the impacted third molar. The purpose of this study was to measure the association of applying melatonin in the socket of an impacted mandibular third molar with osteogenic activity and the anti-inflammatory effects.

METHODS

This prospective, randomized, blinded trial comprised of patients who required removal of the impacted mandibular third molar. The patients were divided into two groups (n = 19) as follows: melatonin group (3 mg of melatonin into 2 ml of 2% hydroxyethyl cellulose gel was packed into the socket) and placebo group (2 ml of 2% hydroxyethyl cellulose gel was placed in the socket). The primary outcome was bone density, measured using Hounsfield unit immediately after surgery and 6 months later. Secondary outcome variables included serum osteoprotegerin level (Ng/ml) that measured immediately, 4 weeks and 6 months postoperatively. Other clinical outcome measures were pain by visual analog scale, maximum mouth opening (MMO) (millimeter), and swelling (millimeter) that were evaluated immediately, 1, 3, and 7 days postoperatively. The data were analyzed by independent t-test of Wilcoxon's rank-sum, analysis of variance, and generalized estimating equation (P ≤ .05).

RESULTS

Thirty-eight patients (25 female and 13 males) with a median age of 27 years were enrolled in the study. There was no statistical significance in bone density observed in both groups [melatonin group: 978.5(951.3-1015.8), control group: 965.8 (924.6-998.7), P = .1]. Alternatively, there were statistically significant improvements in osteoprotegerin levels (on week 4), MMO (on day1), and swelling (on day 3) in the melatonin group compared to those in the placebo group [1.9(1.4-2.4), 39.68 ± 1.35, and 14.36 ± 0.80 versus 1.5(1.2-1.4); 38.33 ± 1.20, and 14.88 ± 0.59; P = .02, .003, 0.031, respectively]. The pain values showed statistically significant improvement throughout the follow-up period in the melatonin group compared to the placebo group [5(3-8), 2(1-5), and 0(0-2) versus 7(6-8), 5(4-6), and 2(1-3); P < .001, respectively].

CONCLUSIONS

The results support the anti-inflammatory effect of melatonin in reducing the pain scale and swelling. Furthermore, it plays a role in the improvement of MMO. On the other hand, the osteogenic activity of melatonin could not be detected.

Coaxial electrospun angiogenic nanofiber wound dressing containing advanced platelet rich-fibrin

Advanced platelet-rich fibrin (A-PRF) provides long-term release of growth factors that potentially accelerate wound healing. In this study, core-shell nanofibrous structure of polyvinyl alcohol (PVA) core and gelatin (Gel) shell containing A-PRF is fabricated through coaxial electrospinning method. PVA/(Gel/A-PRF) core-shell nanofibers had the highest porosity, specific surface area and hydrophilicity among all the studied nanofibers. PVA/(Gel/A-PRF) core-shell nanofibers with a tensile stress of 7.43 ± 0.38 MPa and an elastic modulus of 102.05 ± 9.36 MPa had higher mechanical properties than PVA/Gel/A-PRF and PVA/Gel blend nanofibers. PVA/(Gel/A-PRF) nanofibers had a 47.41 ± 1.97 % degradability over 7 days of immersion in PBS. The release of VEGF and PDGF-AB growth factors from PVA/(Gel/A-PRF) core-shell nanofibers and PVA/Gel/A-PRF blend nanofibers were evaluated. It was shown that L929 cell proliferation and adhesion on PVA/(Gel/A-PRF) core-shell nanofibers were significantly higher than other samples. Also, chicken chorioallantoic membrane (CAM) assay revealed that the highest angiogenic potential among the studied samples related to PVA/(Gel/A-PRF) sample. In vivo studies on a rat model showed wound closure for PVA/(Gel/A-PRF) group was 97.83 ± 2.03 % after 11 days. Histopathological and immunohistochemical examinations approved the acceleration of wound healing by PVA/(Gel/A-PRF) core-shell nanofiber dressing. The results strongly recommend the use of PVA/(Gel/A-PRF) core-shell nanofiber dressing for the repair of full-thickness wounds.

Autologous Platelet Concentrates (APCs) for Hard Tissue Regeneration in Oral Implantology, Sinus Floor Elevation, Peri-Implantitis, Socket Preservation, and Medication-Related Osteonecrosis of the Jaw (MRONJ): A Literature Review

Simple Summary

Autologous platelet concentrates with high growth factor levels are used in many fields of dentistry. In recent years, the critical role of blood-derived materials in bone and soft tissue engineering has become apparent. After tooth extraction, the alveolar bone is exposed to progressive bone resorption, which can lead to difficulties in implant placement. Hence, many studies have demonstrated that APCs have the potential for soft tissue and bone regeneration. Furthermore, no inflammatory reactions occur, and they may be used alone or in combination with bone grafts, promoting bone growth and maturation. Moreover, the released growth factors and the presence of fibrin structures can induce osteogenesis. This review aims to provide information regarding the applications, indications, advantages, and disadvantages of three APC techniques in hard tissue regeneration.

Abstract

Over recent years, the usage of autologous platelet concentrates (APCs) has risen in hard tissue regeneration and oral implantology. The purpose of the present review is to offer an overview of the use of three APC techniques in dentistry: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factor (CGF). A narrative summary of articles published between January 2011 and April 2022 is provided. The PubMed, Cochrane Library, Scopus, and Embase databases were used to conduct the search. The following keywords were used in the preliminary: “VEGF”, “TGF-b1”, “PRP”, “PRF”, “CGF”, AND “sinus augmentation” OR “implants” OR “peri-implantitis” OR “socket preservation” OR “MRONJ”. A total of 82 articles was finally included. The review then takes into account the application of the three techniques in different areas of treatment—including oral implantology, sinus floor elevation, peri-implantitis, socket preservation, and medication-related osteonecrosis of the jaw (MRONJ)—as well as their advantages and disadvantages.

Pre-Clinical Study: Immunohistochemical evaluation of matrix metalloproteinase-13 on rabbit (Oryctolagus cuniculus) socket healing after application of platelet-rich fibrin with and without hydroxyapatite

Background: Tissue engineering technology has been used globally and proven to accelerate wound healing. This study aimed to analyse the effect of adding hydroxyapatite (HA) as a scaffold to platelet-rich fibrin (PRF) as a growth factor in accelerating the wound healing process as seen from the expression of matrix metalloproteinase-13 (MMP-13). Methods: This research is an animal experiment conducted on 18 rabbits (Oryctolagus cuniculus). Rabbits were randomly divided into the following three groups of treatment: (G1) the application of PRF group, (G2) the application of PRF+HA group and (C) the control group without any application. Furthermore, each treatment group was split randomly into three groups of observation time. Periodontal tissue biopsy was performed to analyse the histopathological features that were examined on the basis of the level of MMP-13 immunoexpression. Results: MMP-13 immunoexpression in the PRF+HA group showed better histoscore results, indicating a substantial reduction in MMP-13 values compared with other groups. The healing process was shown to increase with increasing observation time (p<0.05), and the PRF+HA group outperformed the PRF and control groups. On day 3, MMP-13 exhibited a dark brown colour of Immunohistochemistry (IHC), which indicated an increase in the expression value of MMP-13 in the early stages of healing, namely, inflammation. On day 14, light brown IHC was seen, especially in group 2, as a reference that the remodeling process had begun. Conclusions: This study indicates that the administration of PRF and HA was capable of reducing the MMP-13 expression that significantly accelerates the socket healing process. Hydroxyapatite is an alloplastic material that has inherent bioactive properties that support osteoconduction, can bind MMPs, and showed faster healing results based on the observation time as documented by immunohistochemistry.

Randomized controlled study on effect of concentrated growth factors on crestal bone levels and peri-implant bone density in dental implants

Introduction:

Modern dentistry aims to restore the comfort and health of the stomatognathic system. Dental implants have emerged as a promising option for this purpose. Concentrated growth factors (CGFs) have been suggested to enhance the healing of bone grafts and enhance the integration of implants into the bone. Growth factors are proteins which regulate the complex process of wound healing. They play an important role in cell migration, cell proliferation, and angiogenesis in the tissue regeneration phase. CGF was first developed by Sacco in 2006. It can be used as a barrier membrane to accelerate soft-tissue healing. CGF does not require any chemical or anticoagulants, and hence, it is free from viral transmission diseases. Crestal bone levels, peri-implant bone density, bleeding, probing depth, mobility, occlusion factors, restoration adequacy, radiographic images, oral hygiene, and patient health status are some of the important parameters for determining longevity of success rates in implant dentistry. This study will assess the peri-implant bone density and crestal bone levels with and without the use of CGF.

Aim:

To evaluate the effect of CGFs on peri-implant bone density and in the preservation of crestal bone levels around dental implants.

Materials and Methods:

Sampling procedure: Random selection of population (Sealed envelope method)

Number of groups: Two-Control group (Group 1) and Experimental group (Group 2)

Sample size: 20

For Group 2, implants were placed with CGF. For Group 1, implants were placed without CGF. The peri-implant bone density and bone levels were measured by Digora and signora software.

Results:

The mean crestal bone loss on the mesial aspect of implants placed in Group 2 is 0.294 mm and Group 1 is 0.345 mm, and the mean crestal bone loss on the distal aspect of implants placed in Group 2 is 0.320 mm and in Group 1 is 0.331 mm. There are no many significant differences on mesial and distal aspects around implants between the two groups Intragroup comparison of bone density values in Group 1 shows the mean difference from baseline to 1 month is 0.6, and after three and 6 months periods are 1.1 and 1.1, respectively, which indicates not much significant improvement in bone density values in Group 1. Intergroup comparison shows a significant difference between both the groups starting from as early as the 1^st month.

Conclusion:

The results of this study indicate that CGF is significantly better in the regeneration of bone around the implants when comparing with nonCGF groups. Although CGF showed improvement in bone formation, there are no many differences in crestal bone level changes on mesial and distal sides of the implants between the two groups.

Effects of Impacted Lower Third Molar Extraction on Periodontal Tissue of the Adjacent Second Molar

The extraction of impacted lower third molars (ILTM) is one of the most common procedures in oral-maxillofacial surgery. Being adjacent to lower second molars, most impacted lower third molars often lead to distal periodontal defects of adjacent second molars. Several symptoms may occur after extraction, such as periodontal pocket formation, loss of attachment, alveolar bone loss and even looseness of second molar resulting in extraction. The distal periodontal defects of second molars are affected by many factors, including periodontal conditions, age, impacted type of third molars, and intraoperative operations. At present, several studies have suggested that dentists can reduce the risk of periodontal defects of the second molar after ILTM extraction through preoperative evaluation, reasonable selection of flap design, extraction instruments and suture type, and necessary postoperative interventions. This review summarizes the research progress on the influence factors, interventions methods and some limitations of distal periodontal defects of adjacent second molar after extraction of impacted mandibular third molars, with the aim of opening up future directions for studying effects of ILTM extraction on periodontal tissue of the adjacent second 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.

An Injectable Fibrin Scaffold Rich in Growth Factors for Skin Repair

Platelet aggregates, such as PRP, PRF, and CGF, have been used alone or in combination with other grafting materials to enhance restoration outcomes. The process for preparing these autografting materials requires two-step centrifugation or specific centrifuges. In this study, we obtained an injectable fibrin scaffold (IFS) rich in growth factors by one-step centrifugation of whole blood from rabbits. The purpose of this study is to introduce some characteristics of IFS. This scaffold was characterized using various techniques, including Masson's trichrome staining, scanning electron microscopy, porosity measurements, and cell counting. The sustained release of growth factors, including PDGF, VEGF, TGF-β1, IGF, FGF, and EGF, was quantified using ELISA assay. The obtained IFS was tested for its effects on cell proliferation, extracellular matrix deposition, and full-thickness skin defect repair. The prepared IFS is characterized by a loose fibrin network structure with white blood cells and platelets that slowly release growth factors and can promote the healing of skin defects via the promotion of cell proliferation, collagen deposition, and tissue revascularization. In addition, its liquid properties and porous structure are conducive to its application as a therapeutic component in tissue engineering.

Evaluation of postoperative changes in the course of mandibular canals impacted by cystic lesions

BACKGROUND

This study aims to determine the positional alterations in the course of mandibular canal, which were caused by the common cystic lesions in the posterior mandible. Also, the effects of treatment methods on bone formation were evaluated.

METHODS

We designed a retrospective cohort study with patients which were treated due to cystic lesions in the maxillofacial region between the years 2012-2018. Forty eight subjects were included and grouped regarding histopathologic diagnoses (radicular dentigerous and odontogenic keratocyst) and treatment methods (enucleation and marsupialization). The mean (range) of patients' age was 31.25 (18-66) years, and there were 32 male and 16 female individuals. The displacement of mandibular canals was verified on preoperative cone-beam computed tomographic images. The measurements of displacement and bone formation were performed on panoramic radiographs. In the statistical analysis of the data, descriptive statistics, parametric independent sample t-test, non-parametric Kruskal Wallis test, and one-way analysis of variance test were utilized.

RESULTS

All the evaluated mandibular canals were replaced by a mean(SD) of 5.46(2.59) mm after the lesions eliminated, which was significant in the marsupialization group (p = 0.002). The bone formation was significantly higher in the enucleation group (p = 0.003). The multiple regression analyses revealed that the treatment methods significantly influenced the replacement of mandibular canal (p < 0.001) and the bone formation (p = 0.026).

CONCLUSION

In cases where there is an adequate distance between the lesion and the mandibular canal, the enucleation technique was found to be superior in terms of bone formation and the amount of bone height obtained.

Effects of ınjectable platelet-rich fibrin in experimental periodontitis in rats

Injectable platelet-rich fibrin (i-PRF) is an effective biological material that positively contributes to angiogenesis, wound healing, inflammation, regeneration processes, etc. This research aimed to evaluate the effect of i-PRF in rats with experimental periodontitis. Following the development of ligature-induced periodontitis, 24 Wistar albino rats were divided into three groups. Group-1: scaling and root planing (only-SRP); Group-2: SRP + i-PRF; Group-3: only- i-PRF. Heart blood from six donors was used for the i-PRF application. i-PRF was administered as a subgingival injection in the relevant groups on the 1st, 3rd, and 7th days. The tissues were evaluated histopathologically and immunohistochemically. Also, bone structures were examined using micro-CT. According to the data obtained, no statistically significant difference was observed among the groups in terms of bone resorption, inflammation, bone volume, bone levels (mesial/distal), and IL-1β, IFN-ɤ, TNF-α, VEGF values (p > 0.05). However, bone mineral density was statistically significantly different among the groups (Group3 > Group2 > Group1) (p < 0.0001). Subgingival injection of only-i-PRF showed promising results in periodontitis treatment but contribution to SRP has not been proved according to this study results. The study results suggested that the i-PRF application was as effective as SRP in reducing bone loss, modulating inflammatory process, and effecting cytokines in experimental periodontitis. The significant effect of i-PRF on bone mineral density was the most remarkable result.

Evaluation of wound healing following surgical extractions using the IPR Scale

OBJECTIVE

To monitor wound healing following surgical extraction of wisdom teeth using the novel Inflammatory Proliferative Remodeling (IPR) Scale.

METHODS

A prospective study design was used. Participants included 94 otherwise healthy adult patients undergoing surgical extraction of a wisdom tooth at a tertiary medical centre from June 2018 to June 2019. The IPR Scale was completed by two resident surgeons in oral and maxillofacial surgery at three time points after the procedure, corresponding to the three phases of wound healing. Mean subscale and total scores were calculated. Patients graded their preoperative anxiety, intraoperative pain, and pain during follow-up on a 10 cm visual analog scale, and the findings were correlated with the IPR Scale scores.

RESULTS

Mean IPR total score (range 0-16) was excellent (14.43 ± 1.45). Mean scores by healing phase were as follows: inflammatory 6.35 ± 1.34 (range 0-8); proliferation, 4.56 ± 0.8 (range 0-5); remodeling, 2.83 ± 0.51 (range 0-3). There was a positive correlation between mean preoperative anxiety level (5.9 ± 3.6) and intraoperative pain perception (2.4 ± 2.4; P = 0.65) and a negative correlation between mean preoperative anxiety level and IPR Scale scores for each healing phase. Two cases were complicated by abscesses which resolved with treatment.

CONCLUSION

The IPR Scale is a promising tool for the effective evaluation of the wound healing process following wisdom tooth extractions. Relaxation methods and behavioural adaptation might help to lower patient anxiety and thereby improve oral wound healing.

Evaluation of the Effect of Platelet-Rich Fibrin on Wound Healing at Split-Thickness Skin Graft Donor Sites: A Randomized, Placebo-Controlled, Triple-Blind Study

Split-thickness skin grafting (STSG) is widely used to heal wounds resulting from trauma, burns, and chronic wounds. This study aimed to determine the true effect of platelet-rich fibrin (PRF) on patients with burn wounds requiring STSG during treatment of donor wounds. This randomized, triple-blind clinical trial was conducted on patients who referred to the burn ward of Vasei Hospital of Sabzevar, Iran, from May 2017 to May 2018. The donor site was randomly divided into 2 groups: PRF and control (Vaseline petrolatum gauze) using Vaseline gauze. In the intervention group, the PRF gel was applied to the wound and covered with Vaseline gauze and wet dressing. Conversely, only Vaseline gauze and wet dressing were applied to the control group. Outcome evaluation was conducted using paired t test and Wilcoxon signed rank-sum test, as appropriate, on days 8 and 15. The mean age of the patients was 33.10 ± 2.60 years, and 51.50% were male. The mean wound healing time in the PRF and control groups was 11.80 ± 3.51 and 16.30 ± 4.32 days, respectively ( P < .001). The PRF group showed significantly higher wound healing rates than the control group at 8 and 15 days dressing ( P < .001 and P < .001, respectively). Moreover, the mean wound healing for all wound healing indices diagnosed by 2 specialists in PRF was higher than control group on days 8 and 15 ( P < .001). We found a statistically significant difference on days 8 and 15 regarding the mean pain levels between the 2 groups ( P < .001). The findings showed that PRF can significantly increase the time and rate of donor wound healing compared with conventional treatment and also reduce the severity of pain.

Platelet-Rich Fibrin as a Bone Graft Material in Oral and Maxillofacial Bone Regeneration: Classification and Summary for Better Application

Platelet-rich fibrin (PRF) is an autologous platelet concentrate that consists of cytokines, platelets, leukocytes, and circulating stem cells. It has been considered to be effective in bone regeneration and is mainly used for oral and maxillofacial bone. Although currently the use of PRF is thought to support alveolar ridge preservation, there is a lack of evidence regarding the application of PRF in osteogenesis. In this paper, we will provide examples of PRF application, and we will also summarize different measures to improve the properties of PRF for achieving better osteogenesis. The effect of PRF as a bone graft material on osteogenesis based on laboratory investigations, animal tests, and clinical evaluations is first reviewed here. In vitro, PRF was able to stimulate cell proliferation, differentiation, migration, mineralization, and osteogenesis-related gene expression. Preclinical and clinical trials suggested that PRF alone may have a limited effect. To enlighten researchers, modified PRF graft materials are further reviewed, including PRF combined with other bone graft materials, PRF combined with drugs, and a new-type PRF. Finally, we will summarize the common shortcomings in the application of PRF that probably lead to application failure. Future scientists should avoid or solve these problems to achieve better regeneration.

A novel method for harvesting concentrated platelet-rich fibrin (C-PRF) with a 10-fold increase in platelet and leukocyte yields

BACKGROUND AND OBJECTIVES

Liquid platelet rich fibrin (PRF; often referred to as injectable PRF) has been utilized as an injectable formulation of PRF that is capable of stimulating tissue regeneration. Our research group recently found that following standard L-PRF protocols (2700 RPM for 12 min), a massive increase in platelets and leukocytes was observed directly within the buffy-coat layer directly above the red blood cell layer. The purpose of this study was to develop a novel harvesting technique to isolate liquid PRF directly from this buffy coat layer and to compare this technique to standard i-PRF.

MATERIALS AND METHODS

Standard high g-force L-PRF and low g-force i-PRF protocols were utilized to separate blood layers. Above the red blood corpuscle layer, sequential 100-μL layers of plasma were harvested (12 layers total; i.e., 1.2 mL, which represents the total i-PRF volume), and 3 layers (3 × 100 μL) were harvested from the red blood cell layer to quantify blood cells. Each layer was then sent for complete blood count (CBC) analysis, and the cell numbers were quantified including red blood cells, leukocytes, neutrophils, lymphocytes, monocytes, and platelets. The liquid PRF that was directly collected from the buffy-coat layer following L-PRF protocols was referred to as concentrated PRF (C-PRF).

RESULTS

The i-PRF protocol typically yielded a 2- to 3-fold increase in platelets and a l.5-fold increase in leukocyte concentration from the 1- to 1.2-mL plasma layer compared to baseline concentrations in whole blood. While almost no cells were found in the first 4-mL layer of L-PRF, a massive accumulation of platelets and leukocytes was found directly within the buffy coat layer demonstrating extremely high concentrations of cells in this 0.3-0.5-mL layer (~ 20-fold increases). We therefore proposed harvesting this 0.3- to 0.5-mL layer directly above the red blood cell corpuscle layer as liquid C-PRF. In general, i-PRF was able to increase platelet numbers by ~ 250%, whereas a 1200-1700% increase in platelet numbers could easily be achieved by harvesting this 0.3-0.5 mL of C-PRF (total platelet concentrations of > 2000-3000 × 10⁹ cells/L).

CONCLUSION

While conventional i-PRF protocols increase platelet yield by 2-3-fold and leukocyte yield by 50%, we convincingly demonstrated the ability to concentrate platelets and leukocytes over 10-fold by harvesting the 0.3-0.5 mL of C-PRF within the buffy coat following L-PRF protocols.

CLINICAL RELEVANCE

Previous studies have demonstrated only a slight increase in platelet and leukocyte concentrations in i-PRF. The present study described a novel harvesting technique with over a 10-fold increase in platelets and leukocytes that can be further utilized for tissue regeneration.

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.

Assessing periapical dental radiographs as a screening parameter for early indications of osteoporosis in postmenopausal periodontal patients and root surface evaluation using spectrochemical analysis

Objectives:

To assess the usefulness of periapical dental radiograph as a screening tool aimed at early signs of osteoporosis in postmenopausal periodontal patients and root surface evaluation using spectrochemical analysis.

Methods:

This study was conducted at the Department of Periodontics, Riyadh Elm University, Riyadh, Saudi Arabia, for 12 months between December 2016 and November 2017. Two groups consisted healthy postmenopausal women having chronic periodontitis and postmenopausal women having chronic periodontitis with osteoporosis. Osteoporosis were evaluated for plaque index (PI); gingival index (GI); clinical attachment level (CAL); probing pocket depth (PPD), and bone mineral density (BMD). A standardized digital dental periapical radiographs were taken for every patient. The spectrochemical analysis was carried out using the self-assembled Laser-Induced Breakdown Spectroscopy (LIBS) system used for qualitative and quantitative analysis of Calcium (Ca), Potassium (K), Phosphorus (P), Fluoride (F), and Magnesium (Mg)

Results:

There was no statistically significant difference between both groups for GI and PI. Similarly PPD and CAL were showing the difference but statistically, significant difference was only for CAL. Value of distance starting from cement enamel junction to the alveolar crest (CEJ-AC) and BMD were having a statistically significant variance between both groups. The differences between osteoporotic and control group were statistically significant regarding Ca with the mean higher in the control group. Furthermore, the variances between the groups in both K and Mg were statistically significant with higher mean in the osteoporotic group (p<0.05).

Conclusion:

The clinical, radiographic, and experimental findings of this study indicated that osteoporosis has a direct effect on the progression rate of periodontal tissue destruction and dental radiographic can be suggested as a screening tool for an early sign of osteoporosis.

Fifteen Years of Platelet Rich Fibrin in Dentistry and Oromaxillofacial Surgery: How High is the Level of Scientific Evidence?

Platelet-rich fibrin is a blood concentrate system used for soft tissue and bone tissue regeneration. In the last decade, platelet rich fibrin (PRF) has been widely used in different indication fields, particularly in oral and maxillofacial surgery. This review investigates the level of scientific evidence of published articles related to the use of PRF for bone and soft tissue regeneration in dentistry and maxillofacial surgery. An electronic literature research using the biomedical search engine “National Library of Medicine” (PubMed-MEDLINE) was performed in May 2017. A total of 392 articles were found, 72 of which were classified for each indication field. When comparing PRF with biomaterials vs biomaterial alone in sinus lift (5 studies; IIa), no statistically significant differences were detected. Socket preservation and ridge augmentation using PRF significantly enhanced new bone formation compared to healing without PRF (7 studies Ib, IIa, IIb). Reepithelialization and bone regeneration was achieved in 96 of 101 patients diagnosed with medication-related osteonecrosis of the jaw (5 studies, III). In periodontology, PRF alone (6 studies; Ib, IIa, IIb) or its combination with biomaterials (6 studies; Ib, IIa, IIb) significantly improved the pocket depth and attachment loss compared to a treatment without PRF. Over 70% of the patients were part of studies with a high level of scientific evidence (randomized and controlled prospective studies). This published evidence (38 articles), with a high scientific level, showed that PRF is a beneficial tool that significantly improves bone and soft tissue regeneration. However, the clinical community requires a standardization of PRF protocols to further examine the benefit of PRF in bone and soft tissue regeneration in reproducible studies, with a higher scientific level of evidence.

Evaluating the possible association between systemic osteoporosis and periodontal disease progression in postmenopausal women

To evaluate the association between systemic osteoporosis and periodontal diseases in postmenopausal women. A total of 300 women aged (50-70 years) were divided into an osteoporotic (OP) group (n = 150) and non-osteoporotic (NOP) group (n = 150) depending on BMD measured using (DXA) at the femoral neck and lumbar spine. Periodontal examination including PI, GI, PPD, and CAL was measured. A standard digital dental panoramic radiograph was taken for each patient and analyzed using specially developed software graphic program to assess the alveolar bone level and BMD. Elemental analysis of root surfaces of extracted teeth was done for detecting Ca, P, F, Mg, and K using (LIBS). Results showed the differences between both groups were not statistically significant in PI, GI, and PPD. A statistically significant difference was found between both groups in CAL, the distance between CEJ-AC and alveolar bone density. Elemental analysis of the root surfaces revealed that Ca was statistically significantly less in the OP group while the differences between both groups regarding F and P were not statistically significant. Mg and K found to be significantly more in the OP group than in the NOP group. To conclude osteoporosis is certainly a risk factor for periodontal disease and seems to plays a vital role in disease progression.

Biomaterials Enabled Cell-Free Strategies for Endogenous Bone Regeneration

Repairing bone defects poses a major orthopedic challenge because current treatments are constrained by the limited regenerative capacity of human bone tissue. Novel therapeutic strategies, such as stem cell therapy and tissue engineering, have the potential to enhance bone healing and regeneration, and hence may improve quality of life for millions of people. However, the ex vivo expansion of stem cells and their in vivo delivery pose technical difficulties that hamper clinical translation and commercial development. A promising alternative to cell delivery-based strategies is to stimulate or augment the inherent self-repair mechanisms of the patient to promote endogenous restoration of the lost/damaged bone. There is growing evidence indicating that increasing the endogenous regenerative potency of bone tissues for therapeutics will require the design and development of new generations of biomedical devices that provide key signaling molecules to instruct cell recruitment and manipulate cell fate for in situ tissue regeneration. Currently, a broad range of biomaterial-based deployment technologies are becoming available, which allow for controlled spatial presentation of biological cues required for endogenous bone regeneration. This article aims to explore the proposed concepts and biomaterial-enabled strategies involved in the design of cell-free endogenous techniques in bone regenerative medicine.

Autologous platelet-rich fibrin: can it secure a better healing?

OBJECTIVE

The aim of this study was to evaluate the efficacy of platelet-rich fibrin (PRF) in the healing of impacted mandibular third molar (M3) extraction sockets.

STUDY DESIGN

This study included 30 patients with bilaterally symmetric impacted M3 (N = 60) requiring transalveolar extraction. All patients were assigned numbers randomly; left-sided M3 patients with odd numbers and right-sided patients with even numbers were categorized into group A (test group), and the other side of the mouth was classified as "group B" (control group). Group A M3 extraction sockets received PRF, whereas group B sockets were closed without PRF. Patients were evaluated for pain and swelling on postoperative days 1, 3, 7, and 14. Bone healing was compared on postoperative weeks 8 and 16. Analysis of variance (ANOVA) and Tukey's multiple comparison tests were applied for statistical analysis.

RESULTS

A total of 30 patients, ages 18 to 40 years, participated in this study. The overall postoperative pain score (visual analogue scale [VAS]) and facial swelling percentages were lower for group A compared with group B (P < .05). Early bone healing was also evident on postoperative radiographs obtained at weeks 8 and 16 in group A (P < .001).

CONCLUSIONS

The use of autologous PRF aids in earlier and better wound healing in a controlled manner.

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.

The use of platelet-rich fibrin with platelet-rich plasma support meniscal repair surgery

Introduction

Platelet-rich fibrin (PRF) is the only autologous blood product that releases growth factors and has scaffolding properties. We hypothesized that the use of PRF and Platelet-rich plasma (PRP) would improve operative results, including the recovery of function and repaired meniscus.

Materials and Methods

Seventeen patients underwent arthroscopic meniscus repair with PRF and PRP (PRF group) using our novel device for the injection of the PRF into the joint. Another five patients as a control group underwent meniscal repair without PRF and PRP (non-PRF group). The groups were compared in terms of clinical results (Tegner Activity Level Scale, Lysholm Knee Scoring Scale, and International Knee Documentation Committee [IKDC] scores) and changes in magnetic resonance imaging (MRI) findings before surgery and 6 months after surgery.

Results

The Lysholm and IKDC scores improved in all patients postoperatively. However, there was no significant differencies in the postoperative score between the PRF group and the non-PRF group. Follow-up MRI findings did not clearly show improvements.

Conclusions

PRF and PRP are autologous, safe, and cost-effective sources of growth factors. Therefore, we propose a new application of PRF and PRP for autologous transplantation in meniscus repair surgery.

Influence of platelet rich fibrin on post-extraction socket healing: A clinical and radiographic study

Aim

The aim of this study was to evaluate clinically and radiographically, extraction socket healing using autologous platelet rich fibrin (PRF).

Materials and methods

Twenty-four subjects needing single tooth simple extractions were selected. Twenty-four extraction sockets were divided into test group (PRF, n = 12) and control group (blood clot, n = 12). PRF was prepared with blood drawn from individuals after extraction using standard technique. PRF was placed in test group sockets followed by pressure application and figure 8 sutures. Sockets in control group were allowed to heal in the presence of blood clot and received a figure 8 suture. Ridge width was assessed using cast analysis with the help of acrylic stent and a pair of calipers. Radiographic analysis of socket surface area was performed using computer graphic software program. The clinical follow up assessments were performed at 1, 4 and 8 weeks. Collected data was assessed using ANOVA and multiple comparisons test.

Results

Subjects were aged between 25 and 50 (mean 37.8) years, including 15 females. The mean horizontal ridge width for sockets in the test group were 11.70 ± 2.37 mm, 11.33 ± 2.30 mm and 10.97 ± 2.33 mm at 1, 4 and 8 weeks respectively. Ridge width proportions were significantly higher among test group as compared to control group between baseline to 4 and 8 weeks respectively. The mean radiographic bone fill (RBF) percentage in the test group, was 74.05 ± 1.66%, 81.54 ± 3.33% and 88.81 ± 1.53% at 1, 4 and 8 weeks respectively. The mean RBF was significantly higher in the test group than control group at all time intervals.

Conclusion

The study outcomes demonstrate that the use of PRF accelerate socket wound healing after tooth extraction as noticed by increased bone fill and reduced alveolar bone width resorption using clinical and radiographic methods.

The Effect of Platelet-Rich Fibrin, Calcium Sulfate Hemihydrate, Platelet-Rich Plasma and Resorbable Collagen on Soft Tissue Closure of Extraction Sites

Rapid and complete soft tissue healing after tooth extraction minimizes surgical complications and facilitates subsequent implant placement. We used four treatment methods and assessed changes in soft tissue socket closure following tooth extraction in humans. The effects of platelet-rich fibrin-calcium sulfate hemihydrate (PRF-CSH), platelet-rich plasma-calcium sulfate hemihydrate (PRP-CSH), a resorbable collagen dressing (RCD), and no grafting material were compared in a randomized, controlled pilot study with a blinded parallel design (N = 23). Patients with a hopeless tooth scheduled for extraction were randomly assigned to one of the four treatment groups. Socket measurements were obtained immediately after extraction and treatment, as well as after 21 days. There was a significant decrease in the total epithelialized external surface area of the extraction sockets in each group at all time points. However, there were no significant differences in soft tissue closure (p > 0.05) at any time point and PRF-CSH or PRP-CSH did not provide any additional benefit to enhance the soft tissue closure of extraction sockets compared with either RCD or sites without graft.

Regenerative potential of leucocyte- and platelet-rich fibrin. Part B: sinus floor elevation, alveolar ridge preservation and implant therapy. A systematic review

AIM

To analyse the effect of leucocyte- and platelet-rich fibrin (L-PRF) on bone regeneration procedures and osseointegration.

MATERIALS AND METHODS

An electronic and hand search was conducted in three databases (MEDLINE, EMBASE and Cochrane). Only randomized clinical trials, written in English where L-PRF was applied in bone regeneration and implant procedures, were selected. No follow-up restrictions were applied.

RESULTS

A total of 14 articles were included and processed. Three subgroups were created depending on the application: sinus floor elevation (SFE), alveolar ridge preservation and implant therapy. In SFE, for a lateral window as well as for the trans-alveolar technique, histologically faster bone healing was reported when L-PRF was added to most common xenografts. L-PRF alone improved the preservation of the alveolar width, resulting in less buccal bone resorption compared to natural healing. In implant therapy, better implant stability over time and less marginal bone loss were observed when L-PRF was applied. Meta-analyses could not be performed due to the heterogeneity of the data.

CONCLUSIONS

Despite the lack of strong evidence found in this systematic review, L-PRF might have a positive effect on bone regeneration and osseointegration.

The effects of a topical gel containing chitosan, 0,2% chlorhexidine, allantoin and despanthenol on the wound healing process subsequent to impacted lower third molar extraction

BACKGROUND

Despite efforts to prevent postoperative discomfort, there are still many immediate side effects associated with the surgical extraction of impacted lower third molars. Cicatrization is a physiological process through which the loss of integrity of oral mucosa is recovered and damaged tissues are repaired. Bexident Post (ISDIN, Spain) is a topical gel that contains chitosan, 0.2% chlorhexidine, allantoin and dexpanthenol. While this gel has many clinical indications, there are no published clinical trials evaluating its use in impacted mandibular third molar surgery. This study aims to clinically evaluate the efficacy of a gel containing chitosan, 0.2% chlorhexidine, allantoin and dexpanthenol on wound healing and reduction of postoperative side effects and complications after extraction of an impacted mandibular third molar.

MATERIAL AND METHODS

A split-mouth design study was carried out on a total of 50 bilaterally and symmetrically impacted third molar extractions, which were randomly placed into either a control group (CG=25) or an experimental group (EG=25). Patients were all informed of the purpose of the study and provided written consent. All procedures were carried out by the same dental practitioner, in accordance with standard surgical protocol. A different dental practitioner, unaware of which treatment had been applied, provided follow-up care. The EG applied 10 ml of topical gel composed of chitosan, 0.2% chlorhexidine, allantoin and dexpanthenol to the surgical wound three times a day for 10 days, patients in the CG did not apply any gel.

RESULTS

The groups were homogeneous insofar as potentially confounding variables. No significant findings were found regarding postoperative swelling and pain. Neither of the groups displayed poor healing or infectious complications of the wound during the postoperative period. In all the recorded follow-ups (Day 7 p=0.001, and Day 14 p=0.01), the wound's aesthetic appearance was better in the EG. Overall treatment tolerance was satisfactory and similar in both groups.

CONCLUSIONS

The gel composed of chitosan, 0.2% chlorhexidine, allantoin and dexpanthenol did not aid in patients' postoperative comfort; however, improved wound healing was observed.

Platelet-Rich Fibrin and Soft Tissue Wound Healing: A Systematic Review

The growing multidisciplinary field of tissue engineering aims at predictably regenerating, enhancing, or replacing damaged or missing tissues for a variety of conditions caused by trauma, disease, and old age. One area of research that has gained tremendous awareness in recent years is that of platelet-rich fibrin (PRF), which has been utilized across a wide variety of medical fields for the regeneration of soft tissues. This systematic review gathered all the currently available in vitro, in vivo, and clinical literature utilizing PRF for soft tissue regeneration, augmentation, and/or wound healing. In total, 164 publications met the original search criteria, with a total of 48 publications meeting inclusion criteria (kappa score = 94%). These studies were divided into 7 in vitro, 11 in vivo, and 31 clinical studies. In summary, 6 out of 7 (85.7%) and 11 out of 11 (100%) of the in vitro and in vivo studies, respectively, demonstrated a statistically significant advantage for combining PRF to their regenerative therapies. Out of the remaining 31 clinical studies, a total of 8 reported the effects of PRF in a randomized clinical trial, with 5 additional studies (13 total) reporting appropriate controls. In those clinical studies, 9 out of the 13 studies (69.2%) demonstrated a statistically relevant positive outcome for the primary endpoints measured. In total, 18 studies (58% of clinical studies) reported positive wound-healing events associated with the use of PRF, despite using controls. Furthermore, 27 of the 31 clinical studies (87%) supported the use of PRF for soft tissue regeneration and wound healing for a variety of procedures in medicine and dentistry. In conclusion, the results from the present systematic review highlight the positive effects of PRF on wound healing after regenerative therapy for the management of various soft tissue defects found in medicine and dentistry.

Evaluation of the efficacy of platelet-rich plasma and platelet-rich fibrin in alveolar defects after removal of impacted bilateral mandibular third molars

AIM AND OBJECTIVES

This study attempted the evaluation of the efficacy of platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) in alveolar defects after removal of bilateral mandibular third molars.

MATERIALS AND METHODS

A total of 30 patients reporting to Department of Oral and Maxillofacial Surgery and having bilateral mandibular third molar impaction in both male and female aged between 18 and 30 years were included in this study. PRF and PRP were placed in extraction site and recalled at 2(nd), 4(th), and 6(th) month postoperatively. Data were statistically analyzed using IBM SPSS software for Windows, version 19.0. IBM Corp., Armonk, NY, USA.

RESULTS

This study showed decreased probing depth in PRF group compared to PRP and control one. This signifies a better soft tissue healing of extraction sockets with PRF as compared to the PRP and the control group and increase in the bone density highlights the use of PRP and PRF certainly as a valid method in inducing hard tissue regeneration.

CONCLUSION

This study indicates a definite improvement in the periodontal health distal to second molar after third molar surgery in cases treated with PRF as compared to the PRP group and control group. Hence, PRP and PRF can be incorporated as an adjunct to promote wound healing and osseous regeneration in mandibular third molar extraction sites.