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

Efficacy of autologous platelet concentrate products for alveolar preservation: A meta-analysis

PURPOSE

The purpose of the study was to systematically evaluate the efficacy of autologous platelet concentrate products in the preservation of the alveolar ridge after tooth extraction through meta-analysis and provide a theoretical basis for the clinical application of autologous platelet concentrates to reduce alveolar bone resorption.

METHODS

This study conducted a meta-analysis of clinical trials between 2013 and 2023, focusing on autologous platelet concentrate products (e.g., PRP, PRF, CGF, and PRCF) used for alveolar ridge preservation after tooth extraction. The analysis included 122 articles and 371 extraction sockets. All statistical analyses were performed using Review Manager version 5.4.

RESULTS

Results indicate that these platelet concentrates effectively reduced changes in horizontal width 1 mm below the alveolar crest and vertical socket height. They also promoted a higher percentage of new bone formation in extraction sockets compared with control groups. However, they did not significantly prevent horizontal bone resorption at 3 and 5 mm below the alveolar crest.

CONCLUSION

In conclusion, autologous platelet concentrates are useful for alveolar ridge preservation, but larger clinical studies are needed to confirm these findings due to the relatively small sample size in this study.

Postextraction infections, prevention, and treatment

Postoperative infection is one of the most common complications of tooth extraction. It may manifest as localized infection or develop to systemic infection. Clinically, oral surgeons can prevent postoperative infections by urging patients to strengthen oral hygiene, applying antibiotics in a rational and compliant manner, and choosing appropriate surgical methods for tooth extraction. For the treatment of infection, the oral surgeon should formulate a response strategy on the basis of different diagnoses. For local infections such as dry socket, delayed alveolar osteitis, gap infection, and marginal osteomyelitis of the jaws, the infection can be controlled by local debridement, therapeutic use of antibiotics, and incise and drain if necessary. For patients suspected of necrotizing fasciitis, timely extensive debridement should be made to reduce the area of tissue necrosis. For those who have received radiotherapy or anti-resorptive drugs, tooth extraction should follow the recommendations of the relevant clinical guidelines or expert consensus to minimize the risk of osteonecrosis of the jaws. For patients with poor systemic health or dysfunction of the immune system, attention should be paid to identifying infective endocarditis and intracranial infection to ensure the life safety of patients. In this study, the author intends to combine literature review and clinical experience to tackle postextraction infection and its prevention to provide a reference for colleagues on oral and maxillofacial surgery.

How to explain the beneficial effects of leukocyte- and platelet-rich fibrin

The survival of an organism relies on its ability to repair the damage caused by trauma, toxic agents, and inflammation. This process involving cell proliferation and differentiation is driven by several growth factors and is critically dependent on the organization of the extracellular matrix. Since autologous platelet concentrates (APCs) are fibrin matrices in which cells, growth factors, and cytokines are trapped and delivered over time, they are able to influence that response at different levels. The present review thoroughly describes the molecular components present in one of these APCs, leukocyte- and platelet-rich fibrin (L-PRF), and summarizes the level of evidence regarding the influence of L-PRF on anti-inflammatory reactions, analgesia, hemostasis, antimicrobial capacity, and its biological mechanisms on bone/soft tissue regeneration.

Effect of platelet-rich fibrin on the recovery after third molar surgery: A systematic review and meta-analysis

This meta-analysis aimed to elucidate the effects of platelet-rich fibrin (PRF) on the recovery of alveolar bone after surgical removal of the mandibular third molars. PubMed, Cochrane Library, Web of Science, and Embase databases were searched from the inception to February 2023 for relevant studies on the application of PRF after the extraction of impacted mandibular third molars, with the language limited to English. Literature screening was conducted by two independent researchers. The Cochrane risk-of-bias tool was adopted for quality evaluation, and Stata 15.0 was used for statistical analysis. A total of 33 randomized controlled trials were included in the present study. Following surgical removal of the mandibular third molars, 1139 tooth sockets were filled with PRF, while 1138 sockets were sutured after conventional saline irrigation. The meta-analyses showed that PRF can relieve pain [(RR 0.454; 95% CI 0.23, 0.891); (SMD -0.74; 95% CI -0.97, 0.52)], improve swelling (SMD -1.48; 95% CI -1.90, -1.06), alleviate trismus (SMD -0.35; 95% CI -0.51, -0.19), reduce dry socket (SMD -0.18; 95% CI -030, -0.05), and promote bone tissue healing (SMD 2.34; 95% CI 0.18, 4.51). The current study confirms that PRF can reduce some postoperative complications. Local application of PRF after lower third molar extraction is a viable method for relieving pain and swelling, reducing the incidence of dry socket and trismus, and increasing bone density. However, whether it can promote soft tissue healing remains unclear. For patients undergoing complicated surgical extraction, local application of PRF into the sockets might be a good option.

Prevalence and Factors Influencing Post-Operative Complications following Tooth Extraction: A Narrative Review

Background

Complications from dental extractions may result in multiple post-operative visits and adversely affect the patient's life. Preventing complications may decrease post-operative morbidity for the individual as well as lower societal costs, such as lost time from work and healthcare costs.

Objectives

This narrative review aims to assess the prevalence and factors influencing post-operative complications following tooth extraction, helping clinicians minimise the risk. Data Sources. Cross-sectional studies. Study Eligibility and Participants. Patients undergoing dental extractions. Our exclusion criteria included in vitro studies, animal studies, terminally ill patients, and tooth loss not due to dental extraction. Literature was collected from "PubMed" and "Web of Science" through search criteria based on the "PICO" framework. Twenty articles were used to formulate a prevalence table, and 156 articles were included for the factors influencing complications. Study Appraisal and Synthesis Methods. This narrative review was reported using the SANRA (a scale for the quality assessment of narrative review articles) checklist. Due to the scope of our narrative review and its associated objectives, the quality of cross-sectional studies (AXIS) will be conducted from the studies outlining the prevalence.

Results

Alveolar osteitis appears to be the most prevalent post-operative complication following tooth extraction. Predisposing factors can be significant in their ability to alter the risk of postoperative complications, and clinicians should provide patient-centred care to mitigate this risk. Limitations. Due to the breadth of context, a systematic review was not feasible, as it may have introduced heterogeneity.

Conclusion

This narrative review has highlighted an array of factors which can influence the prevalence of post-operative complications. Future research would benefit from individually reporting post-operative complications, reducing the heterogeneity in definitions of the complications, and including greater detail on the predisposing factors studied.

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.

Three-dimensional facial swelling evaluation of pre-operative single-dose of prednisone in third molar surgery: a split-mouth randomized controlled trial

BACKGROUND

Facial swelling, pain, and trismus are the most common postoperative sequelae after mandibular third molar (M3M) surgery. Corticosteroids are the most used drugs to reduce the severity of inflammatory symptoms after M3M surgery. This study aimed to evaluate the effect of a single pre-operative dose of prednisone on pain, trismus, and swelling after M3M surgery.

METHODS

This study was designed as a split-mouth randomized, controlled, triple-blind trial with two treatment groups, prednisone (PG) and control (CG). All the parameters were assessed before the extraction (T0), two days (T1), and seven days after surgery (T2). Three-dimensional evaluation of facial swelling was performed with Bellus 3D Face App. A visual analogue scale (VAS) was used to assess pain. The maximum incisal distance was recorded with a calibrated rule to evaluate the trismus. The Shapiro-Wilk test was used to evaluate the normal distribution of each variable. To compare the two study groups, the analysis of variance was performed using a two-tailed Student t-test for normal distributions. The level of significance was set at a = 0.05. Statistical analysis was conducted using the software STATA (STATA 11, StataCorp, College Station, TX).

RESULTS

Thirty-two patients were recruited with a mean age of 23.6 ± 3.7 years, with a male-to-female ratio of 1:3. A total of 64 M3Ms (32 right and 32 left) were randomly assigned to PG or CG. Surgery time recorded a mean value of 15.6 ± 3.7 min, without statistically significant difference between the groups. At T1, PG showed a significantly lower facial swelling compared to CG (PG: 3.3 ± 2.1 mm; CG: 4.2 ± 1.7 mm; p = 0.02). Similar results were recorded comparing the groups one week after surgery (PG: 1.2 ± 1.2; CG: 2.1 ± 1.3; p = 0.0005). All patients reported a decrease in facial swelling from T1 to T2 without differences between the two groups. At T1, the maximum buccal opening was significantly reduced than T0, and no difference between PG (35.6 ± 8.2 mm) and CG (33.7 ± 7.3 mm) (p > 0.05) was shown. Similar results were reported one week after surgery (PG: 33.2 ± 14.4 mm; CG: 33.7 ± 13.1 mm; p > 0.05). PG showed significantly lower pain values compared to CG, both at T1 (PG: 3.1 ± 1.5; CG: 4.6 ± 1.8; p = 0.0006) and T2 (PG: 1.0 ± 0.8; CG: 1.9 ± 1.4; p = 0.0063).

CONCLUSION

Our results showed that pre-operative low-dose prednisone administration could reduce postoperative sequelae by improving patient comfort after M3M surgery and reducing facial swelling two days and one week after surgical procedures.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov - NCT05830747 retrospectively recorded-Date of registration: 26/04/2023.

Platelet-Rich Fibrin in Oral Surgery and Implantology: A Narrative Review

Background

The application of blood concentrates has gained popularity in dentistry in recent years. Platelet-rich fibrin (PRF) has been discussed frequently due to a high content of growth factors and the option of chair-side manufacturing in a simple centrifugation process. PRF is free from adjuvants and inexpensive to produce. The number of studies reporting beneficial effects of PRF in various clinical applications such as alveolar ridge preservation, sinus floor elevation, management and prevention of medical-related osteonecrosis of the jaw, third molar extractions, and guided bone regeneration in dentistry has increased recently. However, to date, neither clinical recommendations nor guidelines are available. The present narrative review aims to summarize the level of evidence on the clinical application of PRF within the field of oral surgery and implantology.

Summary

A literature search in Pubmed and Medline has identified 34 articles as a basis for this narrative review. The effectiveness of the clinical application of PRF has been analyzed for five indications within dentistry: medical-related osteonecrosis of the jaw, wisdom tooth extraction, guided bone regeneration, sinus floor elevation, and alveolar ridge preservation. The amount of data for third molar extractions, socket preservation, and guided bone regeneration is extensive. Less data were available for the use of PRF in combination with sinus floor elevations. There is a lack of studies with scientific evidence on PRF and medical-related osteonecrosis of the jaw; however, studies positively impact patient-related outcome measures. Most studies report on beneficial effects when PRF is additionally applied in intrabony defects. There is no evidence of the positive effects of PRF combined with bone graft materials during sinus floor elevation. However, some benefits are reported with PRF as a sole filling material.

Key Messages

Many recently published studies show the positive clinical impact of PRF. Yet, further research is needed to ensure the validity of the evidence.

Does the Choice of Preparation Protocol for Platelet-Rich Fibrin Have Consequences for Healing and Alveolar Ridge Preservation After Tooth Extraction? A Meta-Analysis

PURPOSE

Multiple preparation protocols for platelet-rich fibrin (PRF) are in use today, and clinical results are often heterogeneous. This study analyzes the impact of the chosen PRF preparation protocol on 1) wound healing and 2) alveolar ridge preservation.

METHODS

For this systematic review and meta-analysis, eligible studies were identified in PubMed and Cochrane databases. Included were randomized controlled and controlled clinical trials with healthy patients treated with PRF after atraumatic tooth extraction compared to untreated socket(s), reporting at least one of the following outcome variables: pain, swelling, soft tissue healing, alveolar osteitis risk, horizontal and vertical bone loss, socket fill, and new bone formation. Main predictor variable was relative centrifugal force (RCF) comparing high RCF (high PRF), intermediate RCF (standard [S-PRF]), low RCF (advanced PRF), and various RCF settings (concentrated growth factor preparation [CGF]). The type of centrifugation tubes (silica-coated plastic and glass) was a secondary predictor. Weighted or standardized mean differences, risk ratio and corresponding 95% confidence intervals were calculated.

RESULTS

Forty studies published between 2012 and 2022 were selected. The pooled effects of all outcomes were significant against untreated sockets. Within the subgroups high PRF or advanced PRF had the lowest efficacy for many outcome parameters. Pain reduction (in visual analog scale units) was highest for S-PRF (-1.18 [-1.48, -0.88], P < .00001) and CGF (-1.03 [-1.16, -0.90], P < .001). The risk ratio of alveolar osteitis (0.09 [0.01, 0.69], P < .02) and soft tissue healing (standardized mean difference = 2.55 [2.06, 3.03], P < .001) were best for CGF. No subgroup differences were found for bone-related outcomes. No meaningful analysis of the tube material effect was possible.

CONCLUSION

This study confirms that PRF is associated with reduced postoperative complications but indicates that preparation protocol influences clinical outcomes. S-PRF and CGF protocols appear to be superior for several outcome parameters.

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.

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.

Local interventions for the management of alveolar osteitis (dry socket)

BACKGROUND

Alveolar osteitis (dry socket) is a complication of dental extractions more often involving mandibular molar teeth. It is associated with severe pain developing 2 to 3 days postoperatively with or without halitosis, a socket that may be partially or totally devoid of a blood clot, and increased postoperative visits. This is an update of the Cochrane Review first published in 2012.  OBJECTIVES: To assess the effects of local interventions used for the prevention and treatment of alveolar osteitis (dry socket) following tooth extraction.

SEARCH METHODS

An Information Specialist searched four bibliographic databases up to 28 September 2021 and used additional search methods to identify published, unpublished, and ongoing studies.

SELECTION CRITERIA

We included randomised controlled trials of adults over 18 years of age who were having permanent teeth extracted or who had developed dry socket postextraction. We included studies with any type of local intervention used for the prevention or treatment of dry socket, compared to a different local intervention, placebo or no treatment. We excluded studies reporting on systemic use of antibiotics or the use of surgical techniques because these interventions are evaluated in separate Cochrane Reviews.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We followed Cochrane statistical guidelines and reported dichotomous outcomes as risk ratios (RR) and calculated 95% confidence intervals (CI) using random-effects models. For some of the split-mouth studies with sparse data, it was not possible to calculate RR so we calculated the exact odds ratio (OR) instead. We used GRADE to assess the certainty of the body of evidence.

MAIN RESULTS

We included 49 trials with 6771 participants; 39 trials (with 6219 participants) investigated prevention of dry socket and 10 studies (with 552 participants) looked at the treatment of dry socket. 16 studies were at high risk of bias, 30 studies at unclear risk of bias, and 3 studies at low risk of bias. Chlorhexidine in the prevention of dry socket When compared to placebo, rinsing with chlorhexidine mouthrinses (0.12% and 0.2% concentrations) both before and 24 hours after extraction(s) substantially reduced the risk of developing dry socket with an OR of 0.38 (95% CI 0.25 to 0.58; P < 0.00001; 6 trials, 1547 participants; moderate-certainty evidence). The prevalence of dry socket varies from 1% to 5% in routine dental extractions to upwards of 30% in surgically extracted third molars. The number of patients needed to be treated (NNT) with chlorhexidine rinse to prevent one patient having dry socket was 162 (95% CI 155 to 240), 33 (95% CI 27 to 49), and 7 (95% CI 5 to 10) for control prevalence of dry socket 0.01, 0.05, and 0.30 respectively.  Compared to placebo, placing chlorhexidine gel intrasocket after extractions reduced the odds of developing a dry socket by 58% with an OR of 0.44 (95% CI 0.27 to 0.71; P = 0.0008; 7 trials, 753 participants; moderate-certainty evidence). The NNT with chlorhexidine gel (0.2%) to prevent one patient developing dry socket was 180 (95% CI 137 to 347), 37 (95% CI 28 to 72), and 7 (95% CI 5 to 15) for control prevalence of dry socket of 0.01, 0.05, and 0.30 respectively. Compared to chlorhexidine rinse (0.12%), placing chlorhexidine gel (0.2%) intrasocket after extractions was not superior in reducing the risk of dry socket (RR 0.74, 95% CI 0.46 to 1.20; P = 0.22; 2 trials, 383 participants; low-certainty evidence).  The present review found some evidence for the association of minor adverse reactions with use of 0.12%, 0.2% chlorhexidine mouthrinses (alteration in taste, staining of teeth, stomatitis) though most studies were not designed explicitly to detect the presence of hypersensitivity reactions to mouthwash as part of the study protocol. No adverse events were reported in relation to the use of 0.2% chlorhexidine gel placed directly into a socket. Platelet rich plasma in the prevention of dry socket  Compared to placebo, placing platelet rich plasma after extractions was not superior in reducing the risk of having a dry socket (RR 0.51, 95% CI 0.19 to 1.33; P = 0.17; 2 studies, 127 participants; very low-certainty evidence).  A further 21 intrasocket interventions to prevent dry socket were each evaluated in single studies, and there is insufficient evidence to determine their effects. Zinc oxide eugenol versus Alvogyl in the treatment of dry socket Two studies, with 80 participants, showed that Alvogyl (old formulation) is more effective than zinc oxide eugenol at reducing pain at day 7 (mean difference (MD) -1.40, 95% CI -1.75 to -1.04; P < 0.00001; 2 studies, 80 participants; very low-certainty evidence) A further nine interventions for the treatment of dry socket were evaluated in single studies, providing insufficient evidence to determine their effects.

AUTHORS' CONCLUSIONS

Tooth extractions are generally undertaken by dentists for a variety of reasons, however, all but five studies included in the present review included participants undergoing extraction of third molars, most of which were undertaken by oral surgeons. There is moderate-certainty evidence that rinsing with chlorhexidine (0.12% and 0.2%) or placing chlorhexidine gel (0.2%) in the sockets of extracted teeth, probably results in a reduction in dry socket. There was insufficient evidence to determine the effects of the other 21 preventative interventions each evaluated in single studies. There was limited evidence of very low certainty that Alvogyl (old formulation) may reduce pain at day 7 in patients with dry socket when compared to zinc oxide eugenol.

Growth Factor Release within Liquid and Solid PRF

Aim: The purpose of this study was to obtain data concerning growth factor release within liquid and solid platelet-rich fibrin (PRF) matrices and to estimate the amount of potential interindividual variations as a basis for further preclinical and clinical trials. Therefore, we aimed to determine possible differences in the release of growth factors between liquid and solid PRF. Materials and Methods: Blood samples obtained from four subjects were processed to both liquid and solid PRF matrices using a standard centrifugation protocol. Five growth factors (vascular endothelial growth factor, VEGF; epidermal growth factor, EGF; platelet-derived growth factor-BB, PDGF-BB; transforming growth factor-β1, TGF-β1; and matrix metallopeptidase 9, MMP-9) have been evaluated at six time points by ELISA over a total observation period of 10 days (1 h, 7 h, 1 d, 2 d, 7 d, and 10 d). Results: Growth factor release could be measured in all samples at each time point. Comparing liquid and solid PRF matrices, no significant differences were detected (p > 0.05). The mean release of VEGF, TGFβ-1, PDGF-BB, and MMP-9 raised to a peak at time point five (day 7) in both liquid and solid PRF matrices. VEGF release was lower in liquid PRF than in solid PRF, whereas those of PDGF-BB and MMP-9 were higher in liquid PRF than in solid PRF at all time points. EGF had its peak release already at time point two after 7 h in liquid and solid matrices (hour 7 EGF solid: mean = 180 pg/mL, SD = 81; EGF liquid: mean = 218 pg/mL, SD = 64), declined rapidly until day 2, and had a second slight peak on day 7 in both groups (day 7 EGF solid: mean = 182 pg/mL, SD = 189; EGF liquid: mean = 81 pg/mL, SD = 70). Conclusions: This study detected growth factor release within liquid and solid PRF matrices with little variations. Further preclinical trials are needed to precisely analyze the growth factor release in larger samples and to better understand their effects on wound healing in different clinical indications.

Sutureless socket technique after removal of third molars: a multicentric, open, randomized controlled trial

BACKGROUND

Although wisdom-tooth extraction is a routine intervention, the postoperative period remains marked by local inflammation classically manifesting as pain, edema and trismus. Furthermore, there is no consensus on the best operative techniques, particularly for the mucosal closure stage on impacted mandibular wisdom teeth.

METHODS

This parallel, randomized, non-blinded study compared pain following removal of impacted third molars, with and without sutures. Patients were electronically allocated 1:1 to extraction with versus without sutures. Patients ≥ 14 years' old scheduled for extraction of four impacted wisdom teeth under general anesthesia at three French hospitals were eligible for inclusion. Exclusion criteria included taking antiplatelet agents or anticoagulants, coagulation disorders or immunosuppression, and planned orofacial surgical procedures or emergency pain/infection. The primary objective was pain evaluated by Visual Analogue Scale on Day 3. Secondary outcomes were edema, trismus, healing, complications, painkiller consumption and quality of life on Day 3 and 31.

RESULTS

Between June 2016 and November 2018, 100 patients were randomized. Finally, 44 patients in the Suture group and 50 patients in the Without Suture group were analyzed. Mean age was 16.5 years and 66.6% of patients were female. After adjustment on center, age and smoking, no statistical difference was seen between groups for pain on Day 3 (p = 0.904). No differences were seen for swelling, trismus, consumption of painkillers, healing, complications or quality of life. Smokers had a 3.65 times higher complications rate (p = 0.0244).

CONCLUSIONS

Sutureless removal of third molars is thus a reliable technique without negative consequence on outcomes, and allows shorter operating time. Smoking is a risk factor for postoperative complications. Trial registration www.

CLINICALTRIALS

gov (NCT02583997), registered 22/10/2015.

Mesenchymal Stem Cells Based Treatment in Dental Medicine: A Narrative Review

Application of mesenchymal stem cells (MSC) in regenerative therapeutic procedures is becoming an increasingly important topic in medicine. Since the first isolation of dental tissue-derived MSC, there has been an intense investigation on the characteristics and potentials of these cells in regenerative dentistry. Their multidifferentiation potential, self-renewal capacity, and easy accessibility give them a key role in stem cell-based therapy. So far, several different dental stem cell types have been discovered and their potential usage is found in most of the major dental medicine branches. These cells are also researched in multiple fields of medicine for the treatment of degenerative and inflammatory diseases. In this review, we summarized dental MSC sources and analyzed their treatment modalities with particular emphasis on temporomandibular joint osteoarthritis (TMJ OA).

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.

Application of platelet-rich fibrin on mandibular third molar extraction: systematic review and Meta-analysis

OBJECTIVES

This study aims to analyze the effectiveness of platelet-rich fibrin (PRF) in mandibular third molar extraction and provide suggestions for alleviating postoperative complications.

METHODS

Pubmed, EMBASE, Web of Science, and SinoMed were searched electronically on February 2020. Randomized controlled trials focusing on PRF usage in mandibular third molar extraction were included. Reviewers assessed the risk of bias in the included literature and extracted data independently using the criteria recommended by the Cochrane Collaboration. Meta-analysis was performed using RevMan 5.3 and STATA 13.0.

RESULTS

Twenty-one studies were included, comprising 991 patients who had mandibular third molar extraction. The topical application of PRF effectively reduced pain after extraction [MD=-12.06, 95%CI (-21.42, -2.71), P=0.01], attenuated post-extraction swelling [MD=-1.42, 95%CI (-2.41, -0.44), P=0.005], and promoted soft tissue hea-ling [MD=0.66, 95%CI (0.34, 0.99), P<0.000 1]. PRF significantly reduced trismus and alveolar osteitis (P<0.05). However, data could not prove whether PRF has any significant positive effect on bone healing compared with the control group (P>0.05).

CONCLUSIONS

Limited clinical evidence indicates that applying PRF after mandibular third molar extraction could reduce pain, swelling, trismus and the occurrence of dry socket and promote soft tissue healing. However, the effect of PRF on bone healing requires further large-scale randomized controlled trials and unified measurement criteria.

Comparing the Effect of Facial Compression Bandage to That of Systemic Dexamethasone on Postsurgical Sequels after Extraction of Impacted Mandibular Third Molars: A Split-mouth Randomized Clinical Trial

AIM: The present study aimed to compare the clinical efficiency of facial pressure bandage, to that of intramuscular injection of dexamethasone (8 mg) on postsurgical sequels (swelling, pain, and trismus) of extraction of impacted mandibular third molar. METHODS: The study implemented a randomized split-mouth design. Patients with symmetrical bilateral impacted molars were eligible for the present trial. Sides were randomly assigned to two groups: pressure bandage group and dexamethasone group. The evaluated postsurgical sequels were extraoral swelling, trismus, and pain after 48 h and 7 days. RESULTS: The study included 42 impacted third molars (n = 42) in 21 patients with a mean age of 23.4 years. Most participants were females (66.7%). The mean postoperative swelling rates after 48 h and 7 days in pressure bandage group were found to be comparable to those of dexamethasone group. No significant difference was found in the mean rates of postoperative trismus between study groups after 48 h and 7 days. Differences in mean pain level scores between the pressure bandage group and dexamethasone group were statistically insignificant after 48 h and 7 days. CONCLUSION: The study findings showed that the effect of the pressure bandage was comparable to dexamethasone effect on the postsurgical sequels after surgical extraction of impacted mandibular third molars.

Effect of Photobiomodulation on the Incidence of Alveolar Osteitis and Postoperative Pain following Mandibular Third Molar Surgery: A Double-Blind Randomized Clinical Trial

The current study aimed to evaluate the effectiveness of photobiomodulation therapy for the prevention of incidence of alveolar osteitis (AO) and postoperative pain following third molar surgery. In this double-blind clinical trial, the impacted teeth of patients having bilateral impacted mandibular third molars were surgically extracted; for each participant, one socket was randomly assigned to receive photobiomodulation treatment, the other received sham treatment. 660 nm 200 mW CW was applied at a distance of ~1cm to 4 points on the occlusal area of extraction socket (beam area at the tissue ~0.64 cm² , 312.5 mW cm^-2 , 1J, 1.6 J cm^-2 ). Also, 810 nm 200 mW CW was applied at tissue surface at three points on the buccal and three points on the lingual gingiva, for 15 s (400 mW cm^-2 , 3 J, 6 J cm^-2 ). There was a statistically meaningful difference in AO frequency between the two groups, and the photobiomodulation group showed lower AO frequency compared with the sham PBM treatment (P-value = 0.035). According to the findings of this study, photobiomodulation therapy reduced the incidence of AO following surgical removal of impacted mandibular third molars. The incidence of AO typically occurs 3-7 days post-extraction, and our results suggest that PBM treatment within the 7 days could help reduce the risk of AO development.

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.

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.

Postoperative effects of intra-alveolar application of 0.2% chlorhexidine or 1% hyaluronic acid bioadhesive gels after mandibular third molar extraction: a double-blind randomized controlled clinical trial

OBJECTIVE

The aim of this study was to analyze the postoperative effects of intra-alveolar applications of 0.2% chlorhexidine (CHL) or 1% hyaluronic (HA) acid bioadhesive gels following the extraction of mandibular impacted third molars (MITMs).

MATERIALS AND METHODS

In this double-blind randomized controlled clinical trial, 90 patients with one asymptomatic MITM were randomized into three group (n = 30 per group): group 1 (0.2% CHL), group 2 (1% HA), and group 3 (control). Visual analogue scales (VAS) were used to assess postoperative pain 24, 48, and 72 h and 7 days after surgery. Postsurgical complications were recorded: trismus, alveolitis osteitis, infection, or hematoma.

RESULTS

In order from least to greatest, postoperative pain at all evaluation times was 0.2% CHL < 1% HA < control. At 24 h, statistically significant differences were found between both study groups and the control groups (0.2% CHL/control: P = 0.001; 1% HA/control: P = 0.010). At 48 and 72 h, significant differences were only found between 0.2% CHL and the control group (P = 0.229 and P = 0.046, respectively). At 7 days, no significant differences were found between any groups. Comparing the incidence of postoperative trismus, alveolitis osteitis, infection, or hematoma, although complications were more frequent in the control group, no statistical differences between groups were found (P > 0.050).

CONCLUSIONS

Both 0.2% CHL and 1% HA bioadhesive gels applied intra-alveolarly minimize the postoperative complications after MITM extraction. Further research is necessary to confirm the present results.

CLINICAL RELEVANCE

This study might help to reduce the postsurgical complications in patients after MITM extraction.

Case reports of medication-related osteonecrosis of the jaw (MRONJ) treated with uncultured stromal vascular fraction and L-PRF

Medication-related osteonecrosis of the jaw (MRONJ) is a challenging affection, considering the absence of a "Gold Standard" treatment. Cell therapy and tissue engineering, using adipose-tissue stromal vascular fraction (SVF) containing mesenchymal stromal cells (MSC) and endothelial progenitor cells (EPC); and a scaffold with healing properties, l-platelet-rich fibrin (L-PRF), could be a therapeutic option. Two cases of MRONJ were treated by tissue engineering. The patients presented respectively a stage-II and a stage-III MRONJ. The protocol consists of SVF injection in the L-PRF applied on the cleaned bone. Patients are followed clinically and by medical imaging (MI) for 18 months. The buccal mucosa was closed within a month. No recurrence was observed during the follow-up. The MI highlighted bone formation. MSC and EPC presence, in the SVF, were confirmed by immunophenotyping. We report the preliminary results of MRONJ patients successfully treated with the association of autologous fresh L-PRF-SVF.

Randomized controlled trial on the effectiveness of absorbable collagen sponge after extraction of impacted mandibular third molar: split-mouth design

Background

The purpose of this study was to compare the effectiveness of absorbable collagen sponge insertion in tooth extraction sites for socket healing of the impacted mandibular third molar.

Methods

Thirty-six patients with bilateral mandibular impacted third molars based on Pell-Gregory and Winter classification were included in this study. This study was a randomized clinical trial utilizing a split-mouth design with one side assigned as collagen sponge insertion and the other side assigned as the control. Post-operative clinical complications, periodontal integrities, and radiographic outcomes were assessed at 1, 2, and 14-weeks post operatively.

Results

Five patients were excluded during the follow-up period due to loss of follow-up. The study was conducted on 31 patients in total. The mean VAS score of collagen sponge insertion side at 1 week post operation was 1.42 ± 1.26, which was significantly lower than the control side (P < 0.05). The mean probing depth of collagen sponge insertion side at 2-week post operation was 5.55 ± 2.28 mm, which was significantly lower than the control side (7.13 ± 1.86; P < 0.05). Other various measurements including radiographic outcomes showed no significant group differences.

Conclusions

Placement of collagen sponge after extraction of mandibular impacted third molar reduced early stage post-operative complications and enhanced initial healing of soft tissues and periodontal defects.

Trial registration

This study was retrospectively registered at the WHO ICTRP platform and Clinical Research Information Service, KCT0003363. Registered 21 Sep 2018.