[Evaluation of the photodynamic effect on the state of microcirculation and oxygenation in periodontal tissues in the treatment of chronic generalized periodontitis]. / Otsenka fotodinamicheskogo vozdeistviya na sostoyanie mikrotsirkulyatsii i oksigenatsii v tkanyakh parodonta pri lechenii khronicheskogo generalizovannogo parodontita.

OBJECTIVE: Increasing the effectiveness of treatment of chronic generalized periodontitis using PDT based on clinical and functional substantiation of the effects of a photosensitizer. MATERIALS AND METHODS: A clinical and functional study and treatment of moderate chronic generalized periodontitis was carried out in 62 people (26 men and 36 women) aged from 35 to 55 years without a somatic model with an orthognathic occlusion diagnosed according to ICD-10 - K05.3. Of these, 2 groups were divided depending on the type of treatment: Group 1 (main) - patients with moderate chronic generalized periodontitis - 32 people. (17 men and 15 women, average age of the group - 43.2±2.2 years); Group 2 (control) - patients with moderate chronic generalized periodontitis - 30 people. (14 men and 16 women, average age of the group - 44.0±3.3 years). Complex treatment consisted of sanitation of the mouth, removal of dental plaque and curettage of periodontal pockets in group 1, followed by PDT with Revixan gel using a special wired aligner REVIXAN DENTAL LED (16 r). The clinical condition of the periodontium was assessed using the Greene Vermillion Hygienic Index (OHI-S), the Mühlleman Bleeding Index (SBI) modified by Cowell, and the periodontal index PI. To study the state of microcirculation in the gum tissue, the laser Doppler flowmetry (LDF) method was used using the LAKK-M device (NPP «Lazma¼, Russia). The state of microcirculation was assessed by the microcirculation index (M), which characterizes the level of tissue blood flow; parameter - «σ¼, which determines the fluctuation of the erythrocyte flow. According to Wavelet analysis of LDF-grams, the shunt index (SH) of blood flow was determined. In the «LDF + spectrometry¼ mode, oxygenation in periodontal tissues was studied using optical tissue oximetry (OTO), based on the results of which the perfusion saturation index (Sm) and the specific oxygen consumption index (U, %) were determined. RESULTS: According to LDF data, after PDT (group 1), normalization of clinical indices and the level of microcirculation in periodontal tissues was established, which was accompanied by an increase in the level of blood flow (M) and its activity (σ), which persisted after 3 and 6 months. after PDT. The perfusion saturation index (Sm) and specific oxygen consumption (U) increased more significantly after PDT, which persisted after 3 and 6 months. In the control group, the dynamics of indicators was less pronounced. CONCLUSION: The use of PDT with Revixan gel normalizes the clinical condition of the periodontium, indicators of microhemodynamics and oxygen metabolism.

The impact of Thiopeptide antibiotics on inflammatory responses in periodontal tissues through the regulation of the MAPK pathway.

Periodontitis is a bacteria-induced inflammatory disease that damages the tissues supporting the teeth, gums, periodontal ligaments, and alveolar bone. Conventional treatments such as surgical procedures, anti-inflammatory drugs, and antibiotics, are somewhat effective; however, these may lead to discomfort and adverse events, thereby affecting patient outcomes. Therefore, this study aimed to find an effective method to prevent the onset of periodontal disease and explore the specific mechanisms of their action.The impact of thiostrepton on Porphyromonas gingivalis and periodontal ligament stem cells was evaluated in an inflammatory microenvironment. In vivo experiments were performed using a mouse periodontitis model to assess the effectiveness of locally applied thiostrepton combined with a silk fibroin hydrogel in impeding periodontitis progression. Thiostrepton exhibited significant antimicrobial effects against Porphyromonas gingivalis and anti-inflammatory properties by regulating the MAPK pathway through DUSP2. Locally applied thiostrepton effectively impeded the progression of periodontitis and reduced tissue damage. Thiostrepton treatment is a promising and tolerable preventive strategy for periodontitis, offering antimicrobial and anti-inflammatory benefits. These findings suggest the potential of thiostrepton as a valuable addition to periodontitis management, warranting further research and clinical exploration to improve patient outcomes.

Impacto do uso sistêmico de estatinas e de bisfosfonatos nos tecidos periodontais: revisão narrativa / Impact of the systemic use of statins and bisphosphonates in the periodontal tissues: narrative review

Introdução: A literatura tem apontado uma possível relação entre diversas condições sistêmicas e as doenças periodontais. Dentro das doenças sistêmicas que podem gerar o uso crônico de medicamentos, com potencial associação com as doenças periodontais, destacam-se a hipercolesterolemia e o uso de estatinas; e as doenças do metabolismo ósseo e o uso de bisfosfonatos. Objetivo: Dessa maneira, o presente estudo objetivou revisar a literatura sobre o efeito das estatinas e dos bisfosfonatos nos parâmetros clínicos e radiográficos periodontais de indivíduos adultos. Resultados: Apenas estudos observacionais em humanos foram incluídos. Um estudo mostrou que, em pacientes que apresentam doença periodontal e usam estatina, houve 37% menos bolsas periodontais (profundidade de sondagem ≥4mm) quando comparadas aos que não utilizam a medicação, além de apresentarem menor índice de carga inflamatória e menor perda de inserção clínica. Em relação aos bisfosfonatos em indivíduos com doenças que envolvem o metabolismo ósseo, sugere-se que a utilização do fármaco tem obtido resultados positivos nos parâmetros periodontais, como menores sinais clínicos de inflamação gengival, menor profundidade de sondagem, menor perda de inserção clínica e maior nível de osso alveolar, quando comparados aos que nunca realizam essa terapia. Conclusão: Dessa forma, as estatinas e os bisfosfonatos apresentam efeitos promissores, em pacientes sob tratamento para suas respectivas condições sistêmicas, na melhoria dos parâmetros periodontais, porém é importante salientar que são necessários mais estudos sobre o assunto para melhor entender os reais efeitos a longo prazo do uso desses fármacos.(AU)

Introduction: The literature showed a possible relationship between several systemic conditions and periodontal diseases. Within the systemic diseases that can generate the chronic use of these drugs, potentially related with periodontal diseases, it may be cited the hypercholesterolemia and the use of statins; and bone metabolism diseases and the use of bisphosphonates. Objective: In this sense, the present study aimed to review the literature about the effect of statins and bisphosphonates in the periodontal parameters of adults individuals. Results: Only observational studies in humans were included. A study showed that, in patients with periodontal disease and users of statins, there 37% fewer periodontal pockets (probing depth ≥4mm) when compared to those who do not use the medication, as well as having a lower rate of inflammatory burden and less loss of clinical insertion. Regarding the bisphosphonates in individuals diagnosed with diseases involving bone metabolism, it was suggested that the use of the drug has obtained positive results in periodontal parameters, such as a greater absence of plaque, less clinical signs of gingival inflammation, less probing depth, lower level of clinical insertion and higher level of alveolar bone when compared to those who never undergo this therapy. Conclusion: Thus, statins and bisphosphonates have promising effects in patients under treatment for their respective systemic condition in improving periodontal parameters, but it is important to emphasize that further studies on the subject are needed to better understand the long-term effects of the use of these drugs.(AU)

Dental Follicle Stem Cells Promote Periodontal Regeneration through Periostin-Mediated Macrophage Infiltration and Reprogramming in an Inflammatory Microenvironment.

Dental follicle stem cells (DFSCs) have been verified to promote periodontal regeneration in an inflammatory microenvironment. When coping with inflammatory stimulation, DFSCs highly express periostin, a bioactive molecule closely related to periodontal homeostasis. It is worth exploring whether and how periostin plays a role in the promotion of periodontal regeneration by DFSCs. By tracking the fate of DFSCs, it was found that DFSCs significantly contributed to periodontal regeneration in rat periodontal defects while they had a low survival rate. They highly expressed periostin and improved the immune microenvironment in the defect area, especially via the recruitment and reprogramming of macrophages. Silencing periostin attenuated the effects of DFSCs in promoting periodontal regeneration and regulating macrophages. Recombinant human periostin (rhPeriostin) could not only directly promote macrophage reprogramming through the integrin αM/phosphorylated extracellular signal-regulated kinase (p-Erk)/Erk signaling pathway, but it also exhibited the potential to promote periodontal regeneration in rats when loaded in a collagen matrix. These results indicated that periostin is actively involved in the process by which DFSCs promote periodontal regeneration through the regulation of macrophages and is a promising molecular agent to promote periodontal regeneration. This study provides new insight into the mechanism by which DFSCs promote periodontal regeneration and suggests a new approach for periodontal regeneration therapy.

Injectable and Self-Healing Hydrogels with Double-Dynamic Bond Tunable Mechanical, Gel-Sol Transition and Drug Delivery Properties for Promoting Periodontium Regeneration in Periodontitis.

Injection of a hydrogel loaded with drugs with simultaneous anti-inflammatory and tissue regenerating properties can be an effective treatment for promoting periodontal regeneration in periodontitis. Nevertheless, the design and preparation of an injectable hydrogel with self-healing properties for tunable sustained drug release is still highly desired. In this work, polysaccharide-based hydrogels were formed by a dynamic cross-linked network of dynamic Schiff base bonds and dynamic coordination bonds. The hydrogels showed a quick gelation process, injectability, and excellent self-healing properties. In particular, the hydrogels formed by a double-dynamic network would undergo a gel-sol transition process without external stimuli. And the gel-sol transition time could be tuned by the double-dynamic network structure for in situ stimuli involving a change in its own molecular structure. Moreover, the drug delivery properties were also tunable owing to the gel-sol transition process. Sustained drug release characteristics, which were ascribed to a diffusion process, were observed during the first stage of drug release, and complete drug release owing to the gel-sol transition process was achieved. The sustained drug release time could be tuned according to the double-dynamic bonds in the hydrogel. The CCK-8 assay was used to evaluate the cytotoxicity, and the result showed no cytotoxicity, indicating that the injectable and self-healing hydrogels with double-dynamic bond tunable gel-sol transition could be safely used in controlled drug delivery for periodontal disease therapy. Finally, the promotion of periodontal regeneration in periodontitis in vivo was investigated using hydrogels loaded with ginsenoside Rg1 and amelogenin. Micro-CT and histological analyses indicated that the hydrogels were promising candidates for addressing the practical needs of a tunable drug delivery method for promoting periodontal regeneration in periodontitis.

Improved Healing after Non-Surgical Periodontal Therapy Is Associated with Higher Protein Intake in Patients Who Are Non-Smokers.

The aim of this study was to determine whether a relationship between periodontal healing and protein intake exists in patients undergoing non-surgical treatment for periodontitis. Dietary protein intake was assessed using the 2005 Block food frequency questionnaire in patients with chronic generalized periodontitis undergoing scaling and root planing (n = 63 for non-smokers, n = 22 for smokers). Protein intake was correlated to post-treatment probing depth using multiple linear regression. Non-smoking patients who consumed ≥1 g protein/kg body weight/day had fewer sites with probing depth ≥ 4 mm after scaling and root planing compared to patients with intakes <1 g protein/kg body weight/day (11 ± 2 versus 16 ± 2, p = 0.05). This relationship was strengthened after controlling for baseline probing depth, hygienist and time between treatment and follow-up (10 ± 2 versus 16 ± 1, p = 0.018) and further strengthened after controlling for potential confounders including age, sex, body mass index, flossing frequency, and bleeding on probing (8 ± 2 versus 18 ± 2, p < 0.001). No associations were seen in patients who smoked. Consuming ≥1 g protein/kg body weight/day was associated with reductions in periodontal disease burden following scaling and root planing in patients who were non-smokers. Further studies are needed to differentiate between animal and plant proteins.

Recombinant Human Derived Growth and Differentiating Factors in treatment of periodontal intrabony defects: Systematic review and network meta-analysis.

The introduction of recombinant human growth and differentiation factors (rhGFs) for intrabony defects regeneration has represented a considerable breakthrough in recent years. However, they have been used in different concentrations, doses and combined with various scaffolds, and there is no evidence on which the most effective formulation for periodontal regeneration is. Therefore, we aimed to evaluate and rank the various formulations of such bioactive agents through network meta-analysis of clinical studies. The protocol registration was done on PROSPERO with registration ID CRD42020213753. To report NMA, we followed PRISMA guidelines and searched PUBMED, Embase, Web of Science and Cochrane Central electronic databases. Studies were screened based on specific inclusion criteria. Primary outcomes extracted from included studies were the most common indexes for periodontal regeneration (PPD, CAL, %bone filling). The NMA analysis included network plots, contribution plots, inconsistency plots (if eligible to form the loop), predictive interval plots, SUCRA rankings and multidimensional scale ranking (MDS) plots. SUCRA would demonstrate the rankings of multiple competing bioactive agents based on their best performance. Twelve clinical studies for qualitative and quantitative analysis were considered. Network meta-analysis found that rhFGF + hyaluronic acid was ranked highest in PPD and CAL outcome. rhPDGF-BB + ß-tricalcium phosphate was ranked highest in the percentage of bone filling. In addition, all bioactive agents performed better than control groups without rhGFs. Despite clear benefits deriving from rhGFs for periodontal regeneration, the present results should be interpreted with caution due to several confounding factors affecting the outcome. Nevertheless, further well designed randomized clinical trials will allow establishing guidelines for an appropriate indication of the use of rhGFs.

The effect of hyaluronic acid on the periodontium in spontaneous periodontitis in rats / El efecto del ácido hialurónico sobre el periodonto en periodontitis espontánea en ratas

SUMMARY: The aim of the article was to study changes in periodontal tissues in rats with spontaneous periodontitis (SP) and to evaluate the effect of hyaluronic acid (HA) on the state of the periodontium. Wistar rats with signs of SP were divided into 6 groups: 1) intact group; 2) intact animals with HA "HD-1,0 MDa"; 3) SP group; 4) SP with HA "S-2,4 MDa"; 5) SP with HA "ST-2,4 MDa"; 6) SP with HA "HD-1,0 MDa". The study of the periodontium rats with SP noted the main structural changes (collagen reduction, resorption of alveolar bone, dilatation and stasis of the vessels of the periodontium, gingival papilla and tooth pulp), which were assessed as moderate. Morphological evidence of inflammation was infiltration of neutrophils into the connective tissue of the gums, without the formation of abscesses. Local administration of HA did not cause additional structural damage in periodontal tissues of rats with SP, but also did not affect changes in the microvascular system of periodontium and tooth pulp, periodontal ligaments, only a tendency to inhibit alveolar bone resorption in rats was noted. One can consider the tendency to improve the condition of periodontal tissues in the group of rats injected with high molecular HA and HA with mannitol (2.4 MDa).

RESUMEN: El objetivo del artículo fue estudiar los cambios en los tejidos periodontales en ratas con periodontitis espontánea (PE) y evaluar el efecto del ácido hialurónico (HA) sobre el estado del periodonto. Las ratas Wistar con signos de PE se dividieron en 6 grupos: 1) grupo intacto; 2) animales intactos con HA "HD-1,0 MDa"; 3) grupo PE; 4) PE con HA "S-2,4 MDa"; 5) PE con HA "ST-2,4 MDa"; 6) PE con HA "HD-1,0 MDa". En las ratas con PS se observaron los principales cambios estructurales (reducción de colágeno, reabsorción del hueso alveolar, dilatación y estasis de los vasos del periodonto, papila gingival y pulpa dentaria), que fueron evaluados como moderados. La evidencia morfológica de inflamación fue la infiltración de neutrófilos en el tejido conectivo de las encías, sin la formación de abscesos. La administración local de HA no causó daño estructural adicional en los tejidos periodontales de las ratas con PE, pero tampoco se produjo cambios en el sistema microvascular del periodonto y en la pulpa dental y ligamentos periodontales.Se observó una tendencia a inhibir la resorción del hueso alveolar. Se puede considerar la tendencia a mejorar el estado de los tejidos periodontales en el grupo de ratas inyectadas con HA de alto peso molecular y HA con manitol (2,4 MDa).

Application of Propolis in Protecting Skeletal and Periodontal Health-A Systematic Review.

Chronic inflammation and oxidative stress are two major mechanisms leading to the imbalance between bone resorption and bone formation rate, and subsequently, bone loss. Thus, functional foods and dietary compounds with antioxidant and anti-inflammatory could protect skeletal health. This review aims to examine the current evidence on the skeletal protective effects of propolis, a resin produced by bees, known to possess antioxidant and anti-inflammatory activities. A literature search was performed using Pubmed, Scopus, and Web of Science to identify studies on the effects of propolis on bone health. The search string used was (i) propolis AND (ii) (bone OR osteoporosis OR osteoblasts OR osteoclasts OR osteocytes). Eighteen studies were included in the current review. The available experimental studies demonstrated that propolis could prevent bone loss due to periodontitis, dental implantitis, and diabetes in animals. Combined with synthetic and natural grafts, it could also promote fracture healing. Propolis protects bone health by inhibiting osteoclastogenesis and promoting osteoblastogenesis, partly through its antioxidant and anti-inflammatory actions. Despite the promising preclinical results, the skeletal protective effects of propolis are yet to be proven in human studies. This research gap should be bridged before nutraceuticals based on propolis with specific health claims can be developed.

Controlled release of iodine from cross-linked cyclodextrin metal-organic frameworks for prolonged periodontal pocket therapy.

Effective therapeutic system to periodontitis was designed using cross-linked cyclodextrin metal-organic framework (COF) as carrier for iodine and further suspended in hydroxyethyl cellulose gel as I2@COF-HEC hydrogel. Inclusion of iodine within the COF was demonstrated by SR-FTIR spectral and characteristic DSC and TGA changes. Molecular modelling identified the interaction of iodine with both COF central cavity and individual cyclodextrin moieties of COF. In vitro results of study demonstrated that iodine release in artificial saliva from I2@COF-HEC hydrogel could be extended up to 5 days, which was slower than I2@COF particles. Using an in vivo rat model of periodontitis, micro-computed tomography of alveolar bone morphology demonstrated that I2@COF-HEC hydrogel showed similar effects in decreasing periodontal pocket depth and alveolar bone resorption to minocycline ointment, a periodontitis antibiotic. The I2@COF-HEC hydrogel is a novel local delivery device of iodine as a broad spectrum antimicrobial use for treatment of periodontitis.

Regeneration potential of decellularized periodontal ligament cell sheets combined with 15-deoxy-Δ12,14-prostaglandin J2 nanoparticles in a rat periodontal defect.

Periodontitis is a chronic inflammatory disease characterized by loss of attachment and destruction of the periodontium. Decellularized sheet, as an advanced tissue regeneration engineering biomaterial, has been researched and applied in many fields, but its effects on periodontal regeneration remain unclear. In this study, the biological properties of decellularized human periodontal ligament cell (dHPDLC) sheets were evaluated in vitro. Polycaprolactone/gelatin (PCL/GE) nanofibers were fabricated as a carrier to enhance the mechanical strength of the dHPDLC sheet. 15-deoxy-[Formula: see text]-prostaglandin J2 (15d-PGJ2) nanoparticles were added for anti-inflammation and regeneration improvement. For in vivo analysis, dHPDLC sheets combined with 15d-PGJ2 nanoparticles, with or without PCL/GE, were implanted into rat periodontal defects. The periodontal regeneration effects were identified by microcomputed tomography (micro-CT) and histological staining, and immunohistochemistry. The results revealed that DNA content was reduced by 96.6%. The hepatocyte growth factor, vascular endothelial growth factor, and basic fibroblast growth factor were preserved but reduced. The expressions or distribution of collagen I and fibronectin were similar in dHPDLC and nondecellularized cell sheets. The dHPDLC sheets maintained the intact structure of the extracellular matrix. It could be recellularized by allogeneic human periodontal stem ligament cells and retain osteoinductive potential. Newly formed bone, cementum, and PDL were observed in dHPDLC sheets combined with 15d-PGJ2 groups, with or without PCL/GE nanofibers, for four weeks post-operation in vivo. Bringing together all these points, this new construct of dHPDLC sheets can be a potential candidate for periodontal regeneration in an inflammatory environment of the oral cavity.

Characteristics and biologic effects of thermosensitive quercetin-chitosan/collagen hydrogel on human periodontal ligament stem cells.

Thermosensitive hydrogels could function as scaffolds and delivery vehicle of natural flavonoids. The current study aimed to investigate effects of chitosan/collagen ratios on properties of thermosensitive beta-glycerophosphate (bGP) chitosan/collagen hydrogels as delivery vehicle of quercetin and then examined effects of quercetin-hydrogels on growth and cell viability of human periodontal ligament stem cells (hPDLSCs). Microstructure and physical, mechanical and antioxidant properties and quercetin release profiles of the hydrogels were investigated. Fourier transform infrared spectroscopy and X-ray powder diffraction analyses were performed to examine gelation process of the hydrogels. Antioxidant assays were conducted to measure antioxidant capacity of quercetin-hydrogels. It was found that bGP-chitosan/collagen hydrogels exhibited porous structures with interconnected pore architecture and could sustain quercetin release. Chitosan content improved well defined porous structure, increased porosity of the hydrogels and decreased releasing rate of quercetin from the hydrogels. The quercetin-bGP-2:1 (wt/wt) chitosan/collagen hydrogels exhibited antioxidant capacity and were able to promote growth of hPDLSCs in a dose dependent manner. In conclusion, the thermosensitive quercetin-bGP-2:1 (wt/wt) chitosan/collagen hydrogel demonstrated optimal properties of scaffolds for bone tissue engineering and sustained release of natural flavonoids. Incorporating quercetin in the chitosan/collagen hydrogel enhanced bioactive microenvironment that supported stem cell encapsulation.

Comparing the sub-gingival levels of Cytomegalovirus, Epstein-Barr virus, Porphyromonas gingivalis in human immunodeficiency virus-1 seropositive patients with and without antiretroviral therapy.

OBJECTIVES: The effect of antiretroviral therapy (ART) on the oral pathogenic microbes in human immunodeficiency virus-1 seropositive patients remains relatively unexplored. Thus, the present study assessed the effect of ART on the sub-gingival levels of 3 pathogenic microbes. MATERIALS AND METHODS: The study groups consisted of 60 human immunodeficiency virus-1 seropositive patients divided into 3 groups of 20 each. Group 1 had periodontitis and did not start with the ART. Group 2 had periodontitis and started with ART (Tenofovir Disoproxil Fumarate 300 mg + Lamivudine 300 mg + Efavirenz 600 mg) at least 6 months before the study. Group 3 with normal periodontium, and have not started ART. The sub-gingival loads of Cytomegalovirus, Epstein-Barr virus, and the Porphyromonas gingivalis levels were assessed, along with the CD4 counts. RESULTS: The cytomegalovirus load was highest in group 1, followed by groups 2, and 3 (p-value of 0.271). The Epstein-Barr load was highest for group 2, followed by group 3, and 1 (p-value of 0.022). The P.gingivalis load was highest in group 2, followed by groups 1 and 3, (p-value of 0.028). The Epstein-Barr and Cytomegalovirus counts were significantly higher (p-value < 0.02) when the CD4 counts were less than 500 cells/cu3. CONCLUSION: ART did not cause any significant reduction in the sub-gingival levels of any of the 3 examined microbes. Given the lack of any significant effect on the sub-gingival microbial loads by the ART, human immunodeficiency virus patients may require additional anti-microbial agents and regular mechanical plaque removal to maintain their periodontal status.

Necrotizing periodontal diseases in human immunodeficiency virus-infected patients receiving highly active antiretroviral therapy: A review.

Human immunodeficiency virus-infected patients have depleted CD4 lymphocyte counts and are susceptible to a plethora of infections of bacterial, viral, and fungal etiology. In addition to a wide range of systemic manifestations, human immunodeficiency virus-infected patients also display several characteristic oral manifestations. Studies have shown a correlation between some of the oral manifestations and CD4 lymphocyte counts which in turn is an independent prognostic indicator. To tackle the human immunodeficiency virus numerous drugs have been discovered and implemented. To overcome any potential resistance, human immunodeficiency virus patients are prescribed highly active antiretroviral therapy, wherein a combination of antiretroviral regimens are used. Studies have shown that in addition to controlling the viral activity, the treatment regimen, has a significant effect on the oral manifestations of the human immunodeficiency virus-infected patients. The present paper highlights the effects of highly active antiretroviral therapy on periodontal diseases in human immunodeficiency virus-infected individuals.

Wnt signaling: An attractive target for periodontitis treatment.

Periodontitis is the most common chronic inflammatory disease, and a leading cause of tooth loss. Characterized by resorption of alveolar process and destruction of periodontal ligaments, periodontitis can impact not only periodontal tissues but also systemic diseases, such as diabetes, cardiovascular diseases, and respiratory infections. Currently, it is a hotspot to manage destruction and gain regeneration of periodontal tissues. Increasing evidence indicates that the Wnt signaling plays an important role in homeostasis of periodontal tissues, functions of periodontal derived cells, and progression of periodontitis. Its molecule expressions were abnormal in periodontitis. As such, modulators targeting the Wnt signaling may be an adjuvant therapy for periodontitis treatment. This review elucidates the role of Wnt signaling and its molecules, with a view to develop a potential application of drugs targeting the Wnt signaling for periodontitis treatment.

Glucagon-Like Peptide-1 Receptor Agonist Liraglutide Ameliorates the Development of Periodontitis.

Periodontitis is one of the diabetic complications due to its high morbidity and severity in patients with diabetes. The prevention of periodontitis is especially important in diabetic patients because the relationship between diabetes and periodontitis is bidirectional. Here, we evaluated the impacts of glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide on the amelioration of periodontitis. Five-wk-old Male Sprague-Dawley (SD) rats (n = 30) were divided into 3 groups: normal, periodontitis, and periodontitis with liraglutide treatment groups. Periodontitis was induced by ligature around the maxillary second molar in SD rats. Half of the rats were administered liraglutide for 2 weeks. Periodontitis was evaluated by histological staining, gene expressions of inflammatory cytokines in gingiva, and microcomputed tomography. Periodontitis increased inflammatory cell infiltration, macrophage accumulation, and gene expressions of tumor necrosis factor-α and inducible nitric oxide synthase in the gingiva, all of which were ameliorated by liraglutide. Liraglutide decreased M1 macrophages but did not affect M2 macrophages in periodontitis. Moreover, ligature-induced alveolar bone resorption was ameliorated by liraglutide. Liraglutide treatment also reduced osteoclasts on the alveolar bone surface. These results highlight the beyond glucose-lowering effects of liraglutide on the treatment of periodontitis.

Sclerostin antibody stimulates periodontal regeneration in large alveolar bone defects.

Destruction of the alveolar bone in the jaws can occur due to periodontitis, trauma or following tumor resection. Common reconstructive therapy can include the use of bone grafts with limited predictability and efficacy. Romosozumab, approved by the FDA in 2019, is a humanized sclerostin-neutralizing antibody (Scl-Ab) indicated in postmenopausal women with osteoporosis at high risk for fracture. Preclinical models show that Scl-Ab administration preserves bone volume during periodontal disease, repairs bone defects surrounding dental implants, and reverses alveolar bone loss following extraction socket remodeling. To date, there are no studies evaluating Scl-Ab to repair osseous defects around teeth or to identify the efficacy of locally-delivered Scl-Ab for targeted drug delivery. In this investigation, the use of systemically-delivered versus low dose locally-delivered Scl-Ab via poly(lactic-co-glycolic) acid (PLGA) microspheres (MSs) was compared at experimentally-created alveolar bone defects in rats. Systemic Scl-Ab administration improved bone regeneration and tended to increase cementogenesis measured by histology and microcomputed tomography, while Scl-Ab delivered by MSs did not result in enhancements in bone or cemental repair compared to MSs alone or control. In conclusion, systemic administration of Scl-Ab promotes bone and cemental regeneration while local, low dose delivery did not heal periodontal osseous defects in this study.

Tooth-Supporting Hard Tissue Regeneration Using Biopolymeric Material Fabrication Strategies.

The mineralized tissues (alveolar bone and cementum) are the major components of periodontal tissues and play a critical role to anchor periodontal ligament (PDL) to tooth-root surfaces. The integrated multiple tissues could generate biological or physiological responses to transmitted biomechanical forces by mastication or occlusion. However, due to periodontitis or traumatic injuries, affect destruction or progressive damage of periodontal hard tissues including PDL could be affected and consequently lead to tooth loss. Conventional tissue engineering approaches have been developed to regenerate or repair periodontium but, engineered periodontal tissue formation is still challenging because there are still limitations to control spatial compartmentalization for individual tissues and provide optimal 3D constructs for tooth-supporting tissue regeneration and maturation. Here, we present the recently developed strategies to induce osteogenesis and cementogenesis by the fabrication of 3D architectures or the chemical modifications of biopolymeric materials. These techniques in tooth-supporting hard tissue engineering are highly promising to promote the periodontal regeneration and advance the interfacial tissue formation for tissue integrations of PDL fibrous connective tissue bundles (alveolar bone-to-PDL or PDL-to-cementum) for functioning restorations of the periodontal complex.

Investigation of the Effect of Formaldehyde on the Condition of Periodontal Tissues of Woodworking Industry Workers.

The high prevalence of periodontal diseases in workers with professional contact with unfavorable factors of the production environment is an unresolved problem of dentistry. This study aimed to investigate the harmful effects of formaldehyde on periodontal tissues in woodworkers who have long-term contact with formaldehyde in their professional activities. Sixty-nine men with occupational exposure to formaldehyde were examined to study the effect of formaldehyde on the human periodontal tissues, looking particularly at signs of the periodontal tissues' inflammatory process using a series of periodontal indices. The study results showed that the condition of periodontal tissues was statistically significantly worse in woodworkers who have long-term contact with formaldehyde in their professional activities. However, the hygiene status was not significantly different in the main group and the comparison group. Thus, we concluded that working under conditions of constant exposure to formaldehyde has a negative effect on the condition of periodontal tissues.

Lactobacillus-Derived Bioactive Metabolites for the Regulation of Periodontal Health: Evidences to Clinical Setting.

BACKGROUND: Gut microbiota plays a pivotal role in regulating host metabolism that affects the systemic health. To date, several studies have confirmed the fact that microbiota interacts with host, modulating immunity, controlling the homeostasis environment, and maintaining systemic condition. Recent studies have focused on the protective function of poly unsaturated fatty acids, 10-oxo-trans-11-oxadecenoic acid (KetoC) and 10-hydroxy-cis-12-octadecenoic acid (HYA), generated by gut microbiota on periodontal disease. Nevertheless, the mechanism remains unclear as investigations are limited to in vivo and in vitro studies. In this present review, we found that the administration of metabolites, KetoC and HYA, by a probiotic gut microbiota Lactobacillus plantarum from linoleic acid is found to inhibit the oxidation process, possess an antimicrobial function, and prevent the inflammation. These findings suggest the promising use of functional lipids for human health. CONCLUSION: Protective modalities of bioactive metabolites may support periodontal therapy by suppressing bacterial dysbiosis and regulating periodontal homeostasis in the clinical setting.