Treatment of an Infrabony Defect of a Maxillary Canine Tooth Using Enamel Matrix Derivatives with Allogeneic Bone Augmentation in a Dog.

A 5-year-old Miniature Dachshund was presented having an infrabony pocket on the palatal aspect of the right maxillary canine tooth. The bony defect had worsened despite previous closed root planing and administration of a perioceutic agent. A second surgery using an allogeneic cancellous bone augmentation with an enamel matrix derivative was performed in the infrabony defect following open root planing. Eight months after the periodontal surgery, the osseous defect showed healing by improved periodontal probing measurements and increased radiopacity using dental radiography and computed tomography.

Effects of enamel matrix derivative in nonsurgical periodontal therapy on pro-inflammatory profiles, microbial environment and clinical outcome: a randomized clinical trial.

OBJECTIVES: This study aimed to evaluate the impact of enamel matrix derivative (EMD) application following subgingival instrumentation of residual pockets in periodontitis patients on inflammatory host response, microbiological composition, and clinical outcome. METHODS: In this double-blinded randomized controlled trial, a total of 22 patients with generalized periodontitis stage III or IV presenting with ≥ 6 mm probing pocket depth (PPD) at re-evaluation after initial periodontal therapy were included. Participants were randomly allocated at a 1:1 ratio to subgingival instrumentation with (EMD +) or without (EMD-) non-surgical EMD application into the pocket. PPD, clinical attachment level (CAL), bleeding on probing (BoP), plaque index (PI), as well as a panel of pro-inflammatory cytokines and periodontal pathogen count in the gingival crevicular fluid (GCF) of the respective sites were evaluated at baseline (T0) and six months afterwards (T1). RESULTS: Both treatment groups showed a significant PPD reduction (EMD + 1.33 ± 1.15 mm, p < 0.001; EMD- 1.32 ± 1.01 mm, p < 0.001) as well as CAL gain (EMD + 1.13 ± 1.58 mm, p < 0.001; EMD- 0.47 ± 1.06 mm, p = 0.005) from T0 to T1. While no intergroup differences for PPD reduction were observed, CAL gain was higher in EMD + sites compared to EMD- (p = 0.009). No essential effects on cytokine expression as well as bacterial count were detected. CONCLUSIONS: Application of EMD as an adjunct to subgingival instrumentation of residual pockets yielded benefits regarding CAL gain; however, effects on PPD reduction, inflammatory cytokines, and bacterial count were negligible. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04449393), registration date 26/06/2020. CLINICAL RELEVANCE: Based on the obtained results, additional non-surgical EMD application compared to subgingival instrumentation alone showed no clinically relevant effects on treatment outcome and underlying biological mechanisms.

Enamel Matrix Derivative Suppresses Chemokine Expression in Oral Epithelial Cells.

Epithelial cells in periodontitis patients increasingly express chemokines, suggesting their active involvement in the inflammatory process. Enamel matrix derivative (EMD) is an extract of porcine fetal tooth germs clinically applied to support the regrowth of periodontal tissues. Periodontal regeneration might benefit from the potential anti-inflammatory activity of EMD for epithelial cells. Our aim was, therefore, to set up a bioassay where chemokine expression is initiated in the HSC2 oral squamous carcinoma cell line and then test EMD for its capacity to lower the inflammatory response. To establish the bioassay, HSC2 cells being exposed to TNFα and LPS from E. coli (Escherichia coli) or P. gingivalis (Porphyromonas gingivalis) were subjected to RNAseq. Here, TNFα but not LPS caused a robust increase of chemokines, including CXCL1, CXCL2, CXCL8, CCL5, and CCL20 in HSC2 cells. Polymerase chain reaction confirmed the increased expression of the respective chemokines in cells exposed to TNFα and IL-1ß. Under these conditions, EMD reduced the expression of all chemokines at the transcriptional level and CXCL8 by immunoassay. The TGF-ß receptor type I kinase-inhibitor SB431542 reversed the anti-inflammatory activity. Moreover, EMD-activated TGF-ß-canonical signaling was visualized by phosphorylation of smad3 and nuclear translocation of smad2/3 in HSC2 cells and blocked by SB431542. This observation was confirmed with primary oral epithelial cells where EMD significantly lowered the SB431542-dependent expression of CXCL8. In summary, our findings suggest that TGF-ß signaling mediates the effects of EMD to lower the forced expression of chemokines in oral epithelial cells.

Enamel Matrix Derivative (EMD) as an Adjunct to Non-surgical Periodontal Therapy: A Systematic Review.

If left untreated, periodontitis is a chronic, irreversible disease that can contribute to tooth loss. The primary objective of periodontal treatment is to arrest the progression of the disease and restore the supporting structures of the tooth. Scaling and root planing (SRP) is a common non-surgical periodontal therapy (NSPT) used to reduce inflammation, pocket depth, and clinical attachment loss. However, NSPT has limitations, notably in difficult-to-access deep pockets and molar furcations. Deep pockets (greater than 4 mm) frequently retain calculus following NSPT. To attain direct access, surgical periodontal therapy (SPT) is recommended, particularly for pockets deeper than 5 mm. Enamel matrix derivative (EMD) has emerged in recent years as a tool for periodontal regeneration when used in conjunction with NSP for infrabony defects. EMD may also have advantageous effects when combined with NSPT. The purpose of this review is to provide a thorough understanding of the effects of EMD as an adjunct to NSPT. The databases Scopus, PubMed/MEDLINE, Google Scholar, Cochrane, and Embase were systematically searched to identify relevant studies on the benefits of EMD and its use as an adjunct to NSPT. Incorporating EMD into NSPT reduces chair time, and 60% of studies demonstrated considerable benefits compared to SRP alone, according to the findings. On the basis of research, it can be concluded that EMD can be used as an adjunct to NSPT, thereby reducing the amount of time spent in the operating chair. In some cases, it can, therefore, be regarded as an alternative to surgical treatment.

Enhancing attachment of human gingival fibroblasts to periodontally compromised teeth: A comparative analysis of hyaluronic acid, EDTA, enamel matrix derivatives.

Background: Gingival recession is a characteristic indicator of periodontitis and one of the factors that contributes to increased tooth clinical crown length. Patients with root exposure frequently undergo periodontal surgical procedures in addition to adjunctive therapy to increase root coverage area and soft tissue stability. Purpose: This study aimed to evaluate fibroblast-root surface adhesion and determine whether periodontitis-damaged root surface microstructure can be restored using ethylenediaminetetraacetic acid (EDTA) and an enamel matrix derivative (EMD), individually or in combination. Material and methods: Teeth extracted from patients with periodontal disease were used to create 60 samples, with each group containing six specimens. The test groups were provided root planing or root condition-specific materials (hyaluronic acid [HA], 24% EDTA, EMD, or EDTA/EMD) for varying treatment time periods. In contrast, the control group did not undergo any surface modifications. The samples and fibroblast cells were incubated for 72 h. The number of living cells on the root surface in each group was calculated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay (cell viability assessment). Results: The control, root planing, and EMD groups showed that the root surfaces treated with EDTA for 4 min had significantly better cell adhesion. Surface EDTA treatment for 2 min significantly promoted cell attachment compared to root planing treatment. The root surfaces modified with EDTA/EMD for 2 and 4 min showed significantly improved cellular migration and adhesion compared to the root surface treated with root planing. Conclusion: EDTA and EDTA/EMD substantially affected the root surface, which was related to the length of the treatment process. This effect shifts the surface properties, alters fibroblast interactions with the root surface, and recruits more cells to cover a larger area.

Enamel matrix derivative for alveolar ridge preservation: A randomized controlled trial.

OBJECTIVE: The aims of this clinical trial were to evaluate the radiographic dimensional changes in alveolar ridge and patient-reported outcomes following tooth extraction and alveolar ridge preservation (ARP) using either deproteinized bovine bone mineral (DBBM) with EMD or DBBM alone. METHODS: Participants requiring at least one posterior tooth extraction and ARP were randomly allocated into two treatment groups: ARP using either DBBM with EMD or DBBM alone. Cone-beam computed tomography (CBCT) images were recorded immediately prior to extraction and at 6 months. Changes in alveolar ridge height (ARH) and alveolar ridge width (ARW) at 1, 3, and 5 mm were recorded. RESULTS: A total of 18 participants with 25 preserved sites were evaluated. ARH and ARW changed significantly from baseline to 6 months for both treatment groups but the difference between the groups was not statistically significant over the 6-month follow-up period (ARH: DBBM/EMD 1.26 ± 1.53 mm vs. DBBM 2.26 ± 1.60 mm; ARW-1 DBBM/EMD 1.98 ± 1.80 mm vs. DBBM 2.34 ± 1.89 mm). A significant difference, favoring DBBM with EMD group, was observed in percentage of sites that had less than 1 mm loss in ARH (54.5% sites in DBBM/EMD group vs. 14.3% sites in DBBM alone group). The participants' perception of bruising, bleeding, and pain in the first two postoperative days was significantly in favor of DBBM alone group. CONCLUSIONS: There were no significant differences in radiographic mean measurements of ARH and ARW following ARB with DBBM and EMD or DBBM alone.

The Combined Effects of Hydraulic Calcium Silicate Cement and Enamel Matrix Derivative Regarding Osteogenic and Dentinogenic Differentiation on Human Dental Pulp Stem Cells.

The ideal treatment option for immature necrotic permanent teeth is regeneration of the pulp-dentin complex. Mineral trioxide aggregate (MTA), the conventional cement used for regenerative endodontic procedures, induces hard tissue repair. Various hydraulic calcium silicate cements (HCSCs) and enamel matrix derivative (EMD) also promote osteoblast proliferation. The purpose of the present study was to determine the osteogenic and dentinogenic potential of commercially distributed MTA and HCSCs when applied in combination with Emdogain gel on human dental pulp stem cells (hDPSCs). The presence of Emdogain resulted in greater cell viability, and higher alkaline phosphatase activity was detected in the Emdogain-supplemented groups in the early days of cell culture. On qRT-PCR, the groups treated, respectively, with Biodentine and Endocem MTA Premixed in the presence of Emdogain showed an increased expression of the dentin formation marker DSPP, and the group treated with Endocem MTA Premixed in the presence of Emdogain showed an upregulated expression of the bone formation markers OSX and RUNX2. In an Alizarin Red-S staining assay, all of the experimental groups exhibited a greater formation of calcium nodules when treated in combination with Emdogain. Overall, the cytotoxicity and osteogenic/odontogenic potential of HCSCs were similar to that of ProRoot MTA. The addition of the EMD increased the osteogenic and dentinogenic differentiation markers.

Synergy of Regenerative Periodontal Surgery and Orthodontics Improves Quality of Life of Patients with Stage IV Periodontitis: 24-Month Outcomes of a Multicenter RCT.

In stage IV periodontitis patients with pathologic tooth migration (PTM), interdisciplinary treatment includes regenerative periodontal surgery (RPS) with an application of biomaterials and orthodontic therapy (OT) to restore function, esthetics and thereby quality of life (QoL). In a 24-month randomized trial we explored the synergy between regenerative medicine and biomechanical force application. The following methods were used: Forty-three patients had been randomized to a combined treatment comprising RPS and subsequent OT starting either 4 weeks (early OT) or 6 months (late OT) post-operatively. Clinical periodontal parameters and oral health-related QoL (GOHAI) were recorded up to 24 months. We obtained the following results: Mean clinical attachment gain (∆CAL ± SD) was significantly higher with early OT (5.96 ± 2.1 mm) versus late OT (4.65 ± 1.76 mm) (p = 0.034). Pocket closure (PPD ≤ 4 mm) was obtained in 91% of defects with early OT compared to 90% with late OT. GOHAI-scores decreased significantly from 26.1 ± 7.5 to 9.6 ± 4.7 (early OT) and 25.1 ± 7.1 to 12.7 ± 5.6 (late OT). Inconclusion, teeth severely compromised by intrabony defects and PTM can be treated successfully by RPS followed by early OT with the advantage of an overall reduced treatment time. As a result of the combined periodontal-orthodontic therapy, the oral health-related QoL of patients was significantly improved. Early stimulation of wound healing with orthodontic forces had a favorable impact on the outcomes of regenerative periodontal surgery.

Healing of intrabony defects using a novel human recombinant amelogenin: a preclinical study.

OBJECTIVE: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing/regeneration in intrabony defects. METHOD AND MATERIALS: Intrabony defects were surgically created in the mandible of three minipigs. Twelve defects were randomly treated with either rAmelX and carrier (test group) or with the carrier only (control group). At 3 months following reconstructive surgery, the animals were euthanized, and the tissues histologically processed. Thereafter, descriptive histology, histometry, and statistical analyses were performed. RESULTS: Postoperative clinical healing was uneventful. At the defect level, no adverse reactions (eg, suppuration, abscess formation, unusual inflammatory reaction) were observed with a good biocompatibility of the tested products. The test group yielded higher values for new cementum formation (4.81 ± 1.17 mm) compared to the control group (4.39 ± 1.71 mm) without reaching statistical significance (P = .937). Moreover, regrowth of new bone was greater in the test compared to the control group (3.51 mm and 2.97 mm, respectively, P = .309). CONCLUSIONS: The present results provided for the first-time histologic evidence for periodontal regeneration following the use of rAmelX in intrabony defects, thus pointing to the potential of this novel recombinant amelogenin as a possible alternative to regenerative materials from animal origins.

Synergistic effects of enamel matrix derivatives and surface morphology of anodized titanium on osteogenic differentiation of bone marrow mesenchymal stem cells sheet.

OBJECTIVE: To explore the potential osteogenic induction mechanism of enamel matrix derivatives (EMDs) on bone marrow mesenchymal stem cell (BMSC) sheets with different titanium surface morphologies. METHODS: The BMSCs were inoculated on the surfaces of titanium alloys with different morphologies: anodic oxidation (AO), sand-blasted, large grit and acid-etched, and no treatment (control). The proliferation and osteogenic differentiation of BMSCs on the different surface morphologies were observed with the same concentration of EMDs. To further understand the osteogenic mechanism of EMDs on BMSC sheets with different morphologies, a real-time RT-PCR and a western blot were used to detect the overall levels of osteogenic genes and osteogenic proteins. Finally, to verify the osteogenic effect of BMSC sheets stimulated by EMDs in vivo, BMSC sheets with different morphologies were implanted into the subcutaneous tissue of the back of nude mice, and the bone formation was detected by HE staining. RESULTS: The EMDs and surface morphology in the AO group synergically increased the expression levels of osteogenic active factors (RUNX2, OSX and OCN) and enhanced the osteogenic differentiation effect of BMSCs. The in vivo experiments showed that the BMSC sheets in the AO group were rich in osteogenic active factors, and promoted the formation of ectopic bone tissue after implantation into the subcutaneous tissue of the back of nude mice. CONCLUSION: EMDs and AO morphology synergically enhance the secretion of bone osteogenic active factors of BMSCs and promote the formation of heterotopic bone.

Radiographic angle width as predictor of clinical outcomes following regenerative periodontal therapy with enamel matrix derivative: a retrospective cohort study with a mean follow-up of at least 10 years.

OBJECTIVES: To assess the association between the baseline radiographic defect angle and the long-term clinical outcomes following periodontal regenerative therapy with enamel matrix derivative (EMD). METHOD AND MATERIALS: Baseline periapical radiographs obtained from a cohort of patients treated with periodontal regenerative therapy were digitized and the radiographic angle width between the root surface and the bony wall of the adjacent intraosseous defect was calculated and reported (in degrees). Changes in pocket probing depth (PD) and clinical attachment level (CAL) were assessed and reported (in mm). Clinical outcomes were evaluated at baseline (T0), 6 months following therapy (T1), and at the latest follow-up (T2). RESULTS: Thirty-eight defects in 26 patients enrolled in supportive periodontal care for a mean period of 10.4 years (range 8.0 to 15.5 years) were available for analysis. The mean PD change between T0 and T2 was 2.33 ± 1.66 mm at teeth with a defect angle width < 20 degrees and 0.86 ± 1.66 mm at teeth with a defect angle width > 30 degrees (P = .021). When the baseline radiographic angle width was < 20 degrees the probability of obtaining a CAL gain > 3 mm was 1.5-times higher (95% CI 0.19 to 13.8) at T1 and 2.5-times higher (95% CI 0.40 to 15.6) at T2 compared with defects with a radiographic angle width > 30 degrees. CONCLUSION: Within their limitations, these results indicate that pretherapeutic measurement of the radiographic defect angle width might provide relevant information on the short-/long-term clinical outcomes following regenerative periodontal therapy with EMD.

Recession coverage using the modified coronally advanced tunnel and connective tissue graft with or without enamel matrix derivative: 5-year results of a randomised clinical trial.

OBJECTIVES: To evaluate the 5-year results of single and multiple recession type (RT) 1 and 2 (Miller I to III) recessions treated with the modified coronally advanced tunnel (MCAT) and connective tissue graft (CTG) with or without an enamel matrix derivative (EMD). The main outcome variable was the stability of obtained root coverage from 6 months to 5 years. MATERIALS AND METHODS: In 24 patients, both complete and mean root coverage (CRC and MRC) and gain of keratinised tissue (KT) were assessed at 6 months and 5 years after recession coverage by means of MCAT and CTG with or without EMD. Aesthetic outcomes after 5 years were evaluated using the root coverage aesthetic score (RES). RESULTS: At 5 years, 24 patients with a total of 43 recessions were evaluated. Eight patients (57.14%) of the test and 6 (60.0%) of the control group showed complete root coverage. MRC revealed no statistically significant differences between the two groups, with 73.87 ± 26.83% (test) and 75.04 ± 22.06% (control), respectively. KT increased from 1.14 ± 0.57 mm to 3.07 ± 2.27 mm in the test group and from 1.24 ± 0.92 mm to 3.02 ± 1.55 mm in the control group, respectively. CONCLUSION: Treatment of single and multiple RT 1 and 2 recessions by means of MCAT and CTG with or without EMD yielded comparable clinical improvements which could be maintained over a period of 5 years. The additional use of EMD did not influence the clinical outcomes. CLINICAL RELEVANCE: The use of MCAT + CTG yielded successful coverage of single and multiple RT 1 and 2 gingival recessions, while the additional application of EMD did not seem to influence the results.

The Use of Enamel Matrix Derivative during Surgical Therapy for Peri-Implantitis: A Case Series.

Peri-implantitis is a growing concern and currently, there is no agreement on the best method for treating this condition. This study looked at surgical intervention with the use of enamel matrix derivative (EMD) for treating this condition. A cohort of 25 (34 implants) consecutive patients treated with EMD for peri-implantitis was followed for up to 6.4 years. The survival of the implants as well as changes in clinical parameters are reported. Statistical analysis was performed using paired t tests and general estimating equations. The mean length of time implants were followed post-surgery was 3.05 ± 1.53 years. All but two of the treated implants survived in function (94%). Both failed implants were lost in the same patient, who was a heavy smoker. The changes in mean probing depth (1.94 ± 1.18 mm), change in deepest probing depth (3.12 ± 1.45 mm), and reduction in bleeding on probing (73.6 ± 43.9%) according to patient means were all highly significant (p < 0.001 for all changes). When EMD is used during surgical treatment of peri-implantitis, there is a high survival rate of implants and significant improvements in clinical parameters.

Management of Teeth with Grade 3 Endo-Periodontal Lesions by Combined Endodontic and Regenerative Periodontal Therapy.

(1) Background: Severely compromised teeth affected by endo-periodontal lesions are often assigned a "hopeless" prognosis, however, there is only limited evidence available. (2) Methods: In a retrospective study, we evaluated the long-term effectiveness of combined endodontic and regenerative periodontal therapy in teeth with advanced endo-periodontal lesions: 35 patients (age 47-83 years) with a total of 39 teeth diagnosed with grade 3 endo-periodontal lesions were treated by endodontists using an operating microscope followed by regenerative periodontal surgery. (3) Results: Changes in radiographic bone levels (rBl) and probing pocket depths (PPDs) were evaluated after 1 year (T1) and up to 7 years postoperatively (Tfinal). Mean rBL gain was significant with 4.87 ± 3.47 mm after 1 year (T1) and stable results with a mean rBL gain of 4.70 ± 3.37 mm at Tfinal. Mean PPD was significantly reduced from 9.74 ± 2.05 mm at baseline to 5.04 ± 1.61 mm at T1 and to 4.87 ± 2.32 mm at Tfinal. Tooth loss amounted to 10.3% (n = 4) and was due to root fracture. (4) Conclusion: The results suggest that the combined endodontic and regenerative periodontal therapy of endo-periodontal lesions of "hopeless" teeth can lead to favorable long-term results with tooth retention for up to 7 years.

Efficacy of Enamel Matrix Derivative in Periodontal Regeneration Defects: A Systematic Review and Meta-Analysis.

Aim: To evaluate the efficacy of enamel matrix derivative (EMD) on periodontal regeneration defects. Materials and Methods: Four databases were searched until October 2021. Experimental animal studies evaluating the efficacy of EMD were used. The primary outcomes were bone formation (BF) and cementum formation (CF). The secondary outcomes were junctional epithelium (JE), gingival recession (GR), and clinical attachment level (CAL). Measures of effect were mean difference (MD) with 95% confidence intervals (CIs). Random-effects model were used for all meta-analyses. The Systematic Review Centre for Laboratory animal Experimentation tool was used to assess the risk of bias. Results: Seven experimental animal studies (n = 40) used with a maximum follow-up period of 3 months. Compared to control, EMD did not significantly reduce BF (MD 0.02 mm; 95% CI - 1.91-1.96; I2 = 89%). However, it increased CF (MD 1.38 mm; 95% CI 0.01-2.74; I2 = 55%). For secondary outcomes it was found that compared to control, EMD only significantly reduced JE (MD - 0.54 mm; 95% CI - 1.06 to - 0.02; I2 = 55%). However, the other secondary outcomes were not significant as in the case of GR (MD - 3. 88 mm; 95% CI - 68.29-60.53; I2 = 82%), and in CAL (MD 0.02 mm; 95% CI - 0.29-0.39; I2 = 38%). Finally, according to the risk of bias assessment, all included studies had a high risk of bias. Conclusion: EMD had no effect on BF values while it did not reduce CF. Otherwise, in the secondary outcomes, EMD only significantly reduced JE values and had no effect on GR and CAL.

Systematic review of clinical effects of enamel matrix derivative as adjunctive therapy for gingival recession / 口腔疾病防治

Objective @#To evaluate the clinical effect of enamel matrix derivative(EMD) assisted with connective tissue graft(CTG) in the treatment of gingival recession.@*Methods @#Search The Cochrane Library, PubMed, EMbase, Web of Science, Wanfang Public Database,VIP database and CNKI to search for randomized controlled trials of EMD in the treatment of gingival recession. The search period is from the establishment of the databases to October 3, 2022. The test group was treated with EMD+CTG, while the control group was treated with CTG alone. Meta-analyses were performed using Review Manager 5.4.1 and Stat12.0.@*Results@# Meta analysis results showed that only 12 months after treatment, there was a statistically significant difference in the PD and CAL outcome indicators between the EMD assisted treatment group and the control group [MDPD=-0.10, 95% CI (-0.19, -0.01), P = 0.03], [MDCAL=-0.38, 95% CI(-0.71, -0.04), P = 0.03]. There was no significant difference between the test group and the control group in other indicators.@*Conclusion @#EMD assisted CTG in the treatment of gingival recession may be beneficial to the reduction of PD and CAL.

Five-year results following regenerative periodontal surgery with an enamel matrix derivative in patients with different smoking status.

OBJECTIVE: To evaluate the five-year results following regenerative periodontal surgery of intrabony defects using an enamel matrix derivative (EMD) in patients with different smoking status. METHOD AND MATERIALS: The dental records of patients treated with regenerative periodontal surgery with EMD between 2001 and 2011 were screened. The clinical parameters at baseline (T0) and 6 months (T1) and 5 years (T2) after surgery were collected and analyzed in relation to patient's smoking status (smokers, former smokers, and nonsmokers). RESULTS: A total of 71 sites were initially assessed in 38 patients. In total, 56 sites could be evaluated at T1, and 34 after 5 years (T2). At 6 months after surgery, a statistically significant mean probing pocket depth (PPD) reduction of 2.91 ± 1.60 mm and a mean clinical attachment level (CAL) gain of 1.89 ± 1.90 mm were measured. Nonsmokers revealed a greater, statistically not significant CAL gain compared to smokers (2.38 ± 2.12 mm vs 1.50 ± 1.71 mm). Although at 5 years the site-specific PPD values remained stable in nonsmokers, smokers showed an increase of 1.60 ± 2.41 mm. CONCLUSIONS: The present study provides evidence that regenerative periodontal surgery with EMD may lead to clinically relevant improvements even in smoking patients. However, the positive effect of EMD seems to be limited in time and can only partially compensate for the negative influence of smoking.

TGF-ß Signalling Mediates the Anti-Inflammatory Activity of Enamel Matrix Derivative In Vitro.

Enamel matrix derivative (EMD) prepared from extracted porcine fetal tooth material can support the regrow of periodontal tissues. Previous findings suggest that EMD has anti-inflammatory properties and TGF-ß activity in vitro. However, the anti-inflammatory activity of EMD is mediated via TGF-ß has not been considered. To this aim, we first established a bioassay to confirm the anti-inflammatory activity of EMD. The bioassay was based on the RAW 264.7 macrophage cell line and proven with primary macrophages where EMD significantly reduced the forced expression of IL-6. We then confirmed the presence of TGF-ß1 in EMD by immunoassay and by provoking the Smad2/3 nuclear translocation in RAW 264.7 macrophages. Next, we took advantage of the TGF-ß receptor type I kinase-inhibitor SB431542 to block the respective signalling pathway. SB431542 reversed the anti-inflammatory activity of EMD and TGF-ß in a bioassay when IL-6 and CXCL2 expression was driven by the LPS stimulation of RAW 264.7 macrophages. This central observation was supported by showing that SB431542 reversed the anti-inflammatory activity of EMD using IL-1ß and TNF-α-stimulated ST2 bone marrow stromal cells. Together, these findings implicate that the TGF-ß activity mediates at least part of the anti-inflammatory activity of EMD in vitro.

Use of Enamel Matrix Derivative in Minimally Invasive/Flapless Approaches: A Systematic Review with Meta-Analysis.

PURPOSE: The aim of the present systematic review with meta-analysis was to investigate the clinical effectiveness of EMD (enamel matrix derivative) using a minimally invasive surgical technique (MIST) or flapless approach for the treatment of severe periodontal probing depths. MATERIALS AND METHODS: A systematic review of the literature including searches in PubMed/Medline, Cochrane Library, Google Scholar, and Grey Literature databases as well as manual searches was performed on September 1st, 2021. Studies utilising EMD in a non-surgical or minimally invasive approach were included. The eligibility criteria comprised randomised controlled trials (RCTs) comparing minimally-invasive/flapless approaches with/without EMD for the treatment of probing depths >5 mm. RESULTS: From 1525 initial articles, 7 RCTs were included and 12 case series discussed. Three studies investigated a MIST approach, whereas 3 studies utilised a flapless approach. One study compared EMD with either a MIST or a flapless approach. The RCTs included ranged from 19-49 patients with at least 6 months of follow-up. While 5 of the studies included smokers, patients smoking >20 cigarettes/day were excluded from the study. The meta-analysis revealed that EMD with MIST improved recession coverage (REC) and bone fill (BF) when compared to MIST without EMD. However, no difference in CAL or PD was observed between MIST + EMD vs MIST without EMD. No statistically significant advantage was found for employing the EMD via the flapless approach. CONCLUSIONS: Implementing EMD in MIST procedures displayed statistically significant improvement in REC and BF when compared to MIST alone. These findings suggest that MIST in combination with EMD led to improved clinical outcomes while EMD employed in nonsurgical flapless therapy yielded no clinical benefits when compared to nonsurgical therapy alone without EMD. More research is needed to substantiate these findings.

Enamel Matrix Derivative Decreases Pyroptosis-Related Genes in Macrophages.

Background: Pyroptosis is a caspase-dependent catabolic process relevant to periodontal disorders for which inflammation is central to the pathophysiology of the disease. Although enamel matrix derivative (EMD) has been applied to support periodontal regeneration, its capacity to modulate the expression of pyroptosis-related genes remains unknown. Considering EMD has anti-inflammatory properties and pyroptosis is linked to the activation of the inflammasome in chronic periodontitis, the question arises whether EMD could reduce pyroptosis signalling. Methods: To answer this question, primary macrophages obtained from murine bone marrow and RAW 264.7 macrophages were primed with EMD before being challenged by lipopolysaccharide (LPS). Cells were then analysed for pyroptosis-signalling components by gene expression analyses, interleukin-1ß (IL-1ß) immunoassay, and the detection of caspase-1 (CAS1). The release of mitochondrial reactive oxygen species (ROS) was also detected. Results: We report here that EMD, like the inflammasome (NLRP3) and CAS1 specific inhibitors-MCC950 and Ac-YVAD-cmk, respectively-lowered the LPS-induced expression of NLRP3 in primary macrophages (EMD: p = 0.0232; MCC950: p = 0.0426; Ac-YVAD-cmk: p = 0.0317). EMD further reduced the LPS-induced expression of NLRP3 in RAW 264.7 cells (p = 0.0043). There was also a reduction in CAS1 and IL-1ß in RAW 264.7 macrophages on the transcriptional level (p = 0.0598; p = 0.0283; respectively), in IL-1ß protein release (p = 0.0313), and CAS1 activity. Consistently, EMD, like MCC950 and Ac-YVAD-cmk, diminished the ROS release in activated RAW 264.7 cells. In ST2 murine mesenchymal cells, EMD could not be tested because LPS, saliva, and IL-1ß + TNF-α failed to provoke pyroptosis signalling. Conclusion: These findings suggest that EMD is capable of dampening the expression of pyroptosis-related genes in macrophages.