Periodontal Wound Research Articles

In vitro activity of hyaluronic acid and human serum on periodontal biofilm and periodontal ligament fibroblasts

ObjectivesA beneficial effect of cross-linked hyaluronic acid (cHA) on periodontal wound healing and regeneration has recently been demonstrated. The present in vitro study was designed to obtain deeper knowledge on the effect of cHA when applied in the gingival sulcus (serum-rich environment) during non-surgical periodontal therapy.Materials and methodsThe influence of cHA, human serum (HS), and cHA/HS on (i) a 12-species biofilm formation, (ii) the adhesion of periodontal ligament fibroblasts (PDLF) to dentine surface, (iii) the expression and secretion of interleukin-8, and (iv) the expression of receptors of HA in PDLF and gingival fibroblasts (GF) were evaluated.ResultsAt 4 h of biofilm formation, cHA and HS in combination (cHA/HS) slightly decreased the colony-forming unit counts in biofilm whereas the metabolic activity of biofilm was reduced in all test groups (cHA, HS, cHA/HS) vs. control. At 24 h, the quantity of biofilm was reduced in all test groups vs. untreated control. The test substances did not affect adhesion of PDLF to dentin. HS increased the expression of IL-8 by PDLF and GF which was partially downregulated by cHA. HS and/or cHA promoted the expression of the HA receptor RHAMM in GF but not in PDLF.ConclusionsIn summary, the present data indicate that serum neither negatively affect the activity of cHA against periodontal biofilm nor had any unwanted influence on the activity of PDLF.Clinical relevanceThese findings lend additional support for the positive effects of cHA on cells involved in periodontal wound healing, thus pointing to its potential use in non-surgical periodontal therapy.

Induction of Migration and Collagen Synthesis in Human Gingival Fibroblasts Using Periodontal Ligament Stem Cell Conditioned Medium.

This study aimed to examine the effect of periodontal ligament stem cell conditioned medium (PDLSC-CM) on human gingival fibroblast (HGF) migration and collagen synthesis. To assess cell viability, we extracted PDLSC-CM, and the total derived protein concentration was adjusted to 12.5 to 200 µg/mL, followed by treatment with HGFs. The viability of HGFs was observed for 24 hours using the MTT assay. Cell migration was monitored for 24 to 48 hours by wound healing and Boyden chamber assays. Collagen synthesis from HGFs was examined by picrosirius red dye and real-time polymerase chain reaction (PCR) to measure collagen type I and III gene expression for 7 to 10 days. A comparison among the groups was assessed using a one-way analysis of variance (ANOVA) and Bonferroni post hoc test, with the exception of the cell viability assay, which was subjected to Welch's test and Dunnett's T3 post hoc test. HGF viability was significantly enhanced by 12.5, 25, and 50 µg/mL PDLSC-CM. The HGFs treated with 50 µg/mL PDLSC-CM promoted cell migration as shown by wound healing and Boyden chamber assays. At this concentration, collagen synthesis increased at 10 days. Collagen type I gene expression increased by 1.6-fold (p < 0.001) and 4.96-fold (p < 0.001) at 7 and 10 days, respectively. Collagen type III gene expression showed an increase of 1.76-fold (p < 0.001) and 6.67-fold (p < 0.001) at the same time points. Our study suggested that a low concentration of PDLSC-CM at 50 µg/mL has given an amelioration of HGFs providing for periodontal wound healing and periodontal regeneration, particularly migration and collagen synthesis.

Analyzing the relevant factors affecting the clinical outcome of periodontal regeneration surgery

Periodontitis can lead to periodontal tissue defect, tooth mobility and loss, which seriously affects the quality of life. Periodontal regeneration surgery is an important treatment method for repairing periodontal defects, and it is also the hotspot of current periodontal clinical and basic research. A comprehensive understanding of the factors affecting the efficacy of periodontal regenerative surgery can improve clinicians' periodontal treatment concepts, increases the predictability of treatment results, and enhances the level of clinical diagnosis and periodontal treatment. In order to instruct the clinicians, this article will explain the basic principles of periodontal regeneration and the key points of periodontal wound healing, and analyze the elements of periodontal regeneration surgery, which including the patient-related factors, local factors, surgical factors and regenerative material selection.

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

To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing/regeneration in intrabony defects. Intrabony defects were surgically created in the mandible of 3 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. Postoperative clinical healing was uneventful. At the defect level, no adverse reactions (e.g., 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=0.937). Moreover, regrowth of new bone was greater in the test compared to the control group (3.51 mm and 2.97 mm, respectively, p=0.309). 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.

Assessment of tissue healing after periodontal and peri-implant surgery

Relevance. In clinical practice, a dentist usually faces surgical wound healing peculiarities. We know that wound healing by primary intention is preferable, but the postoperative period does not always go this way. In practice, doctors observe a variety of wound healing options, which are not always documented correctly and in full. An incomplete and unprecise diagnosis may lead to c omplications, including iatrogenic ones.Material and methods. This study included patients undergoing surgical treatment in the Samara dental outpatient department. The study assessed the healing of periodontal and peri-implant tissues on the 4th-5th day after surgery. One hundred-and-thirty subjects, aged 27 to 65 y.o., participated in the study.Results. The study revealed the criteria for oral surgical wound healing, which included density and quality of the approximation of wound edges, oedema, exudate, hyperemia, fibrin coat amount, and purulent discharge. The study also recorded the subjective sensations of the patients. After analyzing the postoperative wound condition, we divided the patients into groups according to a similar clinical situation. We identified six types of wound healing processes around implants and teeth. Thus, we formed classes and subclasses of our "Classification of periodontal and peri-implant surgical wound healing assessment." This classification will optimize and simplify communication between specialists and speed up medical charting. The analysis helped to develop and implement a decisionmaking algorithm for postoperative surgical site treatment.Conclusion. The method of soft tissue condition classification and treatment after periodontal and peri-implant surgery is easily reproducible and available in routine outpatient surgical practice. The algorithm will allow for the successful treatment of surgical wounds based on the wound-healing process characteristics.

The therapeutic perspective of cold atmospheric plasma in periodontal disease.

Periodontal disease (PD) is one of the most common infectious diseases with complex inflammatory conditions, having irreversibly destructive impacts on the periodontal supporting tissues. The application of cold atmospheric plasma (CAP) is a promising adjuvant therapy modality for PD. However, the mechanism of CAP in PD treatment is still poorly understood. The review motivates to outline the latest researches concerning the applications of CAP in PD treatment. We searched CAP-related literature through utilizing the well-established databases of Pubmed, Scopus and Web of Science according to the following keywords related to periodontal disease (periodontal, gingival, gingivitis, gingiva, periodontium, periodontitis). A total of 18 concerning original studies were found. These studies could be classified according to three pathophysiological perspectives of PD. The therapeutic mechanisms of CAP may be attributed to the oxidative stress-related cell death of periodontal bacteria, the suppression of periodontal inflammation and pro-inflammatory cytokine secretion, as well as the acceleration of periodontal soft tissue wound healing and hard tissue reconstruction. Cold atmospheric plasma has potential therapeutic effects on PD through three mechanisms: antimicrobial effect, inflammation attenuation, and tissue remodeling. This review hopefully provides a comprehensive perspective into the potential of CAP in PD therapy.

The role of PRX1-expressing cells in periodontal regeneration and wound healing.

The ideal outcome of wound healing is the complete restoration of the structure and function of the original tissue. Stem cells are one of the key factors in this process. Currently, the strategy of periodontal regeneration based on mesenchymal stem cells (MSCs) is generally used to expand stem cells in vitro and then transplant them in vivo. However, their clinical application is limited. In fact, the human body has the capacity to regenerate through stem cells residing in different tissues, even without external therapeutic intervention. Stem cell niches are present in many adult tissues, such as the periodontal ligament and gingiva, and stem cells might remain in a quiescent state in their niches until they are activated in response to a regenerative need. Activated stem cells can exit the niche and proliferate, self-renew, and differentiate to regenerate original structures. Thus, harnessing the regenerative potential of endogenous stem cells in situ has gained increasing attention as a simpler, safer, and more applicable alternative to stem cell transplantation. Nevertheless, there are several key problems to be solved in the application of periodontal mesenchymal stem cells. Thus, animal studies will be especially important to deepen our knowledge of the in vivo mechanisms of mesenchymal stem cells. Studies with conditional knockout mice, in which the expression of different proteins can be eliminated in a tissue-specific manner, are especially important. Post-natal cells expressing the paired-related homeobox protein 1 (PRX1 or PRRX1), a transcription factor expressed in the mesenchyme during craniofacial and limb development, have been shown to have characteristics of skeletal stem cells. Additionally, following wounding, dermal Prx1+ cells are found out of their dermal niches and contribute to subcutaneous tissue repair. Postnatal Prx1+ cells are uniquely injury-responsive. Meanwhile, current evidence shows that Prx1+ cells contribute to promote dentin formation, wound healing of alveolar bone and formation of mouse molar and periodontal ligament. Initial result of our research group also indicates Prx1-expressing cells in bone tissue around the punch wound area of gingiva increased gradually. Collectively, this review supports the future use of PRX1 cells to stimulate their potential to play an important role in endogenous regeneration during periodontal therapy.

Clinical Evaluation of the Combination of rhPDGF-BB and Xenogeneic Bone Substitutes for Treatment of Severe Periodontal Intrabony Defects: A Case Series.

Growth factors are considered an important component for periodontal wound healing and a key element in the periodontal regeneration triad. Randomized controlled clinical trials have demonstrated that purified recombinant human platelet-derived growth factor-BB (rhPDGF-BB) in combination with bone graft materials is effective in treating intrabony periodontal defects. Many clinicians are currently using rhPDGF-BB in combination with xenogeneic or allogeneic bone. Therefore, the purpose of this case series was to assess the clinical effectiveness of combining rhPDGF-BB with xenogeneic bone substitutes to treat severe intrabony periodontal defects. Three patients with challenging deep and wide intrabony defects were treated using a combination of rhPDGF-BB and xenogeneic graft matrix. Probing depth (PD) reduction, bleeding on probing (BOP), mobility reduction, and radiographic bone fill (RBF) were observed for 12 to 18 months. PD decreased from 9 mm to 4 mm, BOP was eliminated, mobility decreased, and RBF ranged from 85% to 95% over the postsurgical observation period. These results indicate that combination of rhPDGF-BB with xenogeneic bone substitutes is a safe and effective graft that leads to favorable clinical and radiographic outcomes for treating severe intrabony periodontal defects. Larger case series or randomized studies will further elucidate the clinical predictability of this treatment protocol. Int J Periodontics Restorative Dent 2023;43:193-200. doi: 1011607/prd.6313.

Effects of ozone therapy on periodontal and peri-implant surgical wound healing: a systematic review.

To evaluate the effectiveness of the use of adjuvant ozone therapy in the healing process of wounds resulting from periodontal and peri-implant surgical procedures by answering the following focused question: "Can adjuvant ozone therapy improve wound healing outcomes related to periodontal and peri-implant surgical procedures?". MEDLINE (via PubMed), EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched, without language restriction, for peer-reviewed articles published until 23 March 2022, in addition to manual search. Only controlled clinical trials (randomized or not) were considered. The risk of bias was evaluated by the Cochrane risk-of-bias tool for RCTs - version 1 (RoB1). Data were pooled into evidence tables and a descriptive summary was presented. Of the 107 potentially eligible records, only seven studies were included. Four addressed free/deepithelialized gingival grafts with a palatal donor area, two evaluated implant sites, and one comprised gingivectomy and gingivoplasty. A total of 225 patients were evaluated in the included studies, considering control and test groups (ozone and other adjuvant therapies for comparison). Ozone therapy had a positive effect on outcomes directly or indirectly related to periodontal/peri-implant surgical wound healing. Furthermore, it could also increase the stability of immediately loaded single implants installed in the posterior mandible. In general, ozone therapy seems to both accelerate the healing processes of periodontal/peri-implant wounds and increase the secondary stability of dental implants; however, considering the limited evidence available and the risk of bias in the included studies (none classified as low risk), a definitive conclusion cannot be drawn. (Quintessence Int 2023;54: 100-110; doi: 10.3290/j.qi.b3512007).

Adipose-derived stem cell spheroid-laden microbial transglutaminase cross-linked gelatin hydrogel for treating diabetic periodontal wounds and craniofacial defects

BackgroundDiabetes mellitus deteriorates the destruction and impairs the healing of periodontal wounds and craniofacial defects. This study is to evaluate the potential of self-assembled adipose-derived stem cell spheroids (ADsp) in microbial transglutaminase cross-linked gelatin hydrogel (mTG) for treating diabetic periodontal wounds and craniofacial defects.MethodsHuman adipose-derived stem cells (ADSCs) were isolated by lipoaspiration, pluripotent genes and trilineage differentiation were examined, and the maintenance of ADsp properties in mTG was verified. Oral mucosal wounds and calvarial osseous defects were created in diabetic rats. Gross observation, histologic evaluation, and immunohistochemistry for proliferating cells and keratinization were conducted in the mucosal wounds within 4–28 days. Micro-CT imaging, histologic evaluation, and immunohistochemistry for proliferating cells and osteogenic differentiation were conducted in the osseous defects at 7 and 28 days.ResultsADSCs expressed pluripotent genes and were capable of trilineage differentiation. ADsp retained morphology and stemness in mTG. In diabetic mucosal wounds, wound closure, epithelization, and keratinization were accelerated in those with ADsp and ADsp-mTG. In diabetic osseous defects, osteogenic differentiation markers were evidently expressed, cell proliferation was promoted from day 7, and bone formation was significantly promoted at day 28 in those with osteogenically pretreated ADsp-mTG.ConclusionsADsp-mTG accelerated diabetic oral mucosal wound healing, and osteogenically pretreated ADsp-mTG promoted diabetic osseous defect regeneration, proving that ADsp-mTG facilitated diabetic periodontal wound healing and craniofacial osseous defect regeneration.

Comparative analysis of proliferative and multilineage differentiation potential of human periodontal ligament stem cells from maxillary and mandibular molars.

Clinical experience indicates that wounds in alveolar bone and periodontal tissue heal faster and more efficiently in the maxilla compared with the mandible. Since stem cells are known to have a decisive influence on wound healing and tissue regeneration, the aim of this study was to determine whether differences in proliferation and differentiation of periodontal ligament stem cells (PDLSC) from upper (u-PDLSC) and lower jaw (l-PDLSC) contribute to the enhanced wound healing in the maxilla. u-PDLSC and l-PDLSC from the same donor were harvested from the periodontal ligament of extracted human maxillary and mandibular third molars. Cell differentiation potential was assessed by analyzing stem cell markers, proliferation rate, and multilineage differentiation among each other and bone marrow-derived mesenchymal stem cells (MSC). Successful differentiation of PDLSC and MSC toward osteoblasts, adipocytes, and chondrocytes was analyzed via reverse transcriptase-quantitative polymerase chain reaction and histochemical staining (Alizarin Red, Oil Red O, Toluidine Blue). u-PDLSC and l-PDLSC expressed the MSC-markers CD73+ , CD90+ , and CD105+ and lacked expression of CD34- and CD45- . Proliferation was significantly higher in u-PDLSC than in l-PDLSC, regardless of the culture conditions. Osteogenic (ALP, RunX2, and osteocalcin) and chondrogenic (SOX9 and ACAN) related gene expression as well as staining intensities were significantly higher in u-PDLSC than in l-PDLSC. No difference in adipogenic differentiation was observed. u-PDLSC showed a significantly higher proliferative and differentiation potential than l-PDLSC, offering a possible cell-based explanation for the differences in periodontal wound healing efficacy between maxilla and mandible.

Periodontal Wound Healing- A Review

Following Periodontal surgery, the site which underwent treatment is always considered as a wound area which has to be healed. This healing process can occur in the form of repair or regeneration. For normal wound healing to happen, the practitioner must understand the concept behind wound healing and possible complications in order to avoid them. With various periodontal therapies available in recent days, the healing pattern also varies with different treatment performed. The goal of this review article is to put forward the outline of periodontal wound healing in order to achieve wound stability and provide a professional treatment for the patient.

Macrophages contribute to periodontal wound healing mainly in the tissue proliferation stage.

The aim of this study was to determine the preliminary role of macrophages in different stages of periodontal healing. Macrophages are promising target cells for periodontal regeneration. However, the stage at which they play a more important role during periodontal repair has not been elucidated till date. First, the dynamic changes in M1 and M2 macrophages were analyzed in a rat periodontal-defect model at Days 1, 3, 5, 7, 14, 21, and 28 post-surgery. Macrophages were then depleted after 1, 6, and 14 days of surgery, and the healing results were evaluated via micro-computed tomography and histopathological detection. Finally, the effects of M1 and M2 macrophages on the proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) were verified in vitro. During natural periodontal healing, the number of M1 macrophages increased the most during the early stage of healing (3 days post-operation), and subsequently, it decreased rapidly. The number of M2 macrophages was at its peak during the middle and late stages of tissue healing (5-21 days post-surgery). Interestingly, the highest number of M2 macrophages was observed at 5-14 days post-operation in the alveolar bone, while it was observed at 21 days post-operation in the cementum area. On the first and 14th day post-operation, the clearance of macrophages had no significant effect on tissue healing; however, on the sixth day post-operation, macrophage depletion significantly inhibited tissue regeneration (p < .05). In vitro studies showed that M2 macrophages, rather than M1 macrophages, could significantly promote the proliferation of MSCs (p < .01). It is better to intervene in tissue proliferation phase when a M2 macrophage regulation-based periodontal regenerative therapy is planned in the future.

Enamel Matrix Derivatives (EMD) in Periodontics - Biomimicry Revisited

Enamel matrix derivatives are a class of xenogeneic proteins that have shown considerable clinical and histological improvements in periodontal wound healing. The proteins array is currently undetermined in its entirety, however it has been extensively studied in periodontal regeneration. It has resulted in true periodontal regeneration, with the formation of all periodontal structures resembling the developmental stages of periodontal structures. The biological cues in this chemical have received FDA approval for human usage in periodontal practise. It is employed in a variety of surgical treatments, including root covering surgery, periodontal regenerative surgery, bone regeneration, ridge augmentation techniques, and has gained popularity in difficult implant regenerative procedures. The creation of this sophisticated biomolecule-based protein concentration is a godsend to periodontists.

Baseline interleukin-10, CD163, and tumor necrosis factor-like weak inducer of apoptosis (TWEAK) gingival tissue levels in relation to clinical periodontal treatment outcomes: A 12-week follow-up study.

The aim of this study was to examine the relationship between healing response after non-surgical periodontal treatment and baseline gingival tissue levels of M2 macrophage activation-related proteins CD163, interleukin (IL)-10, interferon (IFN)-γ, and tumor necrosis factor-like weak inducer of apoptosis (TWEAK), and the CD163/TWEAK ratio. Eighty-eight gingival tissue samples from 44 Stage III/IV, Grade C periodontitis patients (18 smokers) and 41 tissue samples from 41 periodontally healthy participants (18 smokers) were evaluated. Clinical parameters were recorded in periodontally healthy individuals at baseline and in periodontitis patients at pre-treatment and 2, 6, and 12weeks following therapy. IL-10, IFN-γ, CD163, and TWEAK levels were analyzed with Luminex technique. Tissue levels (median, 1st -3rd quartile) of IL-10 (pg/ng protein), CD163 (pg/μg protein) and TWEAK (pg/μg protein) were as follows: IL-10 periodontitis: 2.08, 0.86-5.32 and periodontally healthy: 5.22, 3.20-10.25; CD163 periodontitis: 8.85, 4.92-14.06 and periodontally healthy: 18.36, 12.51-34.02; TWEAK periodontitis: 0.08, 0.05-0.11 and periodontally healthy: 0.16, 0.12-0.21. IL-10, CD163, and TWEAK levels were higher (P<0.001) in periodontally healthy tissues than in periodontitis tissues. Pocket closure at 12weeks was associated with elevated baseline gingival CD163 levels (P =0.047) and CD163/TWEAK ratio (P =0.001). Elevated baseline gingival CD163/TWEAK ratio was associated with pocket reduction at 6 (P =0.022) and 12weeks (P =0.002). Associations of pocket closure with pre-treatment gingival tissue CD163 levels and CD163/TWEAK ratio indicate that baseline M2 macrophage activation profile may play a role in periodontal wound healing.

Case-only design identifies interactions of genetic risk variants at SIGLEC5 and PLG with the lncRNA CTD-2353F22.1 implying the importance of periodontal wound healing for disease aetiology.

The basis of phenotypic variation of periodontitis is genetic variability. Disease relevant effects of individual risk alleles are considered to result from genetic interactions. We investigated gene × gene (G×G) interactions of suggestive periodontitis susceptibility alleles. We used the case-only design and investigated single-nucleotide polymorphism (SNPs) that showed associations in our recent genome-wide association study (GWAS) and GWAS meta-analysis with p < 5 × 10-6 . CRISPR-dCas9 gene activation followed by RNA-sequencing and gene-set enrichment analyses elucidated differentially expressed genes and gene networks. With the databases of SNPInspector and Transfac professional, luciferase reporter gene assays and antibody electrophoretic mobility shift experiments, we analysed allele-specific effects on transcription factor binding. SNPs at the genes sialic acid binding Ig-like lectin 5 (SIGLEC5) and plasminogen (PLG) showed G×G interactions with rs1122900 at the long non-coding RNA (lncRNA) CTD-2353F22. Associated chromatin cis-activated CTD-2353F22.1 6.5-fold (p=.003), indicating CTD-2353F22.1 as target gene of this interaction. CTD-2353F22.1 regulated GADD45A (padj < 4.9 × 10-11 , log2 fold change (FC)=-0.55), THBS1, SERPINE1 and Tissue Factor F3 (padj < 5 × 10-7 , log2 FC ≥ -0.35) and the gene set "angiogenesis" (area under the curve=0.71, padj =8.2 × 10-5 ). rs1122900 effect C-allele decreased reporter gene activity (5.5-fold, p=.0003) and PRDM14 binding (76%). CTD-2353F22.1 mediates interaction of SIGLEC5 and PLG, together with genes that function in periodontal wound healing.

Impact of health and lifestyle food supplements on periodontal tissues and health.

According to the new classification, periodontitis is defined as a chronic multifactorial inflammatory disease associated with dysbiotic biofilms and characterized by progressive destruction of the tooth-supporting apparatus. This definition, based on the current scientific evidence, clearly indicates and emphasizes, beside the microbial component dental biofilm, the importance of the inflammatory reaction in the progressive destruction of periodontal tissues. The idea to modulate this inflammatory reaction in order to decrease or even cease the progressive destruction was, therefore, a logical consequence. Attempts to achieve this goal involve various kinds of anti-inflammatory drugs or medications. However, there is also an increasing effort in using food supplements or so-called natural food ingredients to modulate patients' immune responses and maybe even improve the healing of periodontal tissues. The aim of this chapter of Periodontology 2000 is to review the evidence of various food supplements and ingredients regarding their possible effects on periodontal inflammation and wound healing. This review may help researchers and clinicians to evaluate the current evidence and to stimulate further research in this area.

Cross-linked hyaluronic acid gel with or without a collagen matrix in the treatment of class III furcation defects: A histologic and histomorphometric study in dogs.

To histologically evaluate the effects of cross-linked hyaluronic acid (xHyA) with or without a collagen matrix (CM) on periodontal wound healing/regeneration in class III furcation defects in dogs. Class III furcation defects were surgically created in the mandibular premolars in six beagle dogs. The defects were randomly treated as follows: open flap debridement (OFD) + CM (CM), OFD + xHyA (xHyA), OFD + xHyA + CM (xHyA/CM) and OFD alone (OFD). At 10 weeks, the animals were euthanized for histological evaluation. The newly formed bone areas in the xHyA (4.04 ± 1.51 mm2 ) and xHyA/CM (4.32 ± 1.14 mm2 ) groups were larger than those in the OFD (3.25 ± 0.81 mm2 ) and CM (3.31 ± 2.26 mm2 ) groups. The xHyA (6.25 ± 1.45 mm) and xHyA/CM (6.40 ± 1.35 mm) groups yielded statistically significantly (p< .05) greater formation of new connective tissue attachment (i.e., new cementum, with inserting connective tissue fibres) compared with the OFD (1.47 ± 0.85 mm) group. No significant differences were observed in any of the histomorphometric parameters between the xHyA and xHyA/CM groups. Complete furcation closure was not observed in any of the four treatment modalities. Within their limits, the present results suggest that the use of xHyA with or without CM positively influences periodontal wound healing in surgically created, acute-type class III furcation defects.

Impact of Laser Therapy on Periodontal and Peri-Implant Diseases.

Objective: In the last few decades, lasers in dentistry have encompassed all branches in dentistry, with more focus in periodontology. In recent years, the use of lasers against periodontitis and peri-implantitis has undergone a decisive development that has involved various operational areas. The broadest applications were probably found in the clinical approach to soft tissues. Methods: Laser therapy is a novel technique that may provide further beneficial effects to conventional periodontal and peri-implant therapies. However, clinical evidence for the improvement of periodontal wound healing and tissue regeneration through laser treatment is still limited. Results: This review is aimed at assessing the advantages and disadvantages of the use of lasers in dental procedures and pathologies, focusing more on protocols for the management of periodontal and peri-implant diseases. Conclusions: The adjuvant action of laser therapy, in addition to conventional therapies for the management of periodontal and peri-implant disease, could induce benefits, but further investigation would be necessary to standardize better the protocols applied and to understand the actual tissue response to laser therapy.

M101, a therapeutic oxygen carrier derived from Arenicola marina, decreased Porphyromonas gingivalis-induced hypoxia and improved periodontal healing.

Porphyromonas gingivalis exacerbates tissue hypoxia and worsens periodontal inflammation. This study investigated the effect of a therapeutic oxygen carrier (M101), derived from Arenicola marina, on hypoxia and associated inflammation in the context of periodontitis. The effect of M101 on GLUT-1, GLUT-3, HIF-1α, and MMP-9 expression, hypoxia, and antioxidant status in oral epithelial cells (EC) exposed to CoCl2 (1000 μM), P. gingivalis (MOI 100), and CoCl2 + P. gingivalis was evaluated through hypoxia detection fluorescence assay, antioxidant concentration colorimetric assay, and RTqPCR. Evaluation of M101 on EC proliferation was evaluated in an in vitro wound assay. In experimental periodontitis, periodontal wound healing and osteoclastic activity were compared among natural wound healing, placebo, and gels containing M101 (1 and 2g/L) groups through histomorphometry and TRAP (tartrate-resistant acid phosphatase activity assay) assay respectively. The expression of HIF-1α, MMP-9, and NFκB in periodontal tissues was also evaluated through immunofluorescence studies. M101 downregulated GLUT-1, GLUT-3, HIF-1α, and MMP-9 levels in EC exposed to CoCl2 , P. gingivalis, and CoCl2 + P. gingivalis (p<0.05). Fluorescence and colorimetric analyses confirmed hypoxia reduction and antioxidant capacity improvement in such EC upon M101 treatment. Moreover, M101 improved significantly the in vitro wound closure. In vivo, the attachment level was significantly improved, and osteoclastic activity was reduced in mice treated with M101 gels compared to placebo and natural wound healing groups (p<0.05). HIF-1α, MMP-9, and NFκB expression in periodontal tissues was reduced in M101 gels treated mice compared to the controls. M101 showed promise in resolving hypoxia and associated inflammation-mediated tissue degradation. Its potential in the clinical management of periodontitis must be further investigated.