Global burden of periodontal disease and its relation with socioeconomic development during 1990-2019

Integrating network pharmacology and experimental evaluation to explore the complementary therapeutic effect and mechanism of melatonin in periodontitis

Objective

To explore the potential targets for melatonin in the treatment of periodontitis through network pharmacologic analysis and experimental validation via in vivo animal models and in vitro cellular experiments.

Materials and methods

In this study, we first screened melatonin targets from Pharm Mapper for putative targets, Drug Bank, and TCMSP databases for known targets. Then, disease database was searched and screened for differential expressed genes associated with periodontitis. The intersection of disease and melatonin-related genes yielded potential target genes of melatonin treatment for periodontitis. These target genes were further investigated by protein-protein interaction network and GO/KEGG enrichment analysis. In addition, the interactions between melatonin and key target genes were interrogated by molecular docking simulations. Then, we performed animal studies to validate the therapeutic effect of melatonin by injecting melatonin into the peritoneal cavity of ligation-induced periodontitis (LIP) mice. The effects of melatonin on the predicted target proteins were also analyzed using Western blot and immunofluorescence techniques. Finally, we constructed an in vitro cellular model and validated the direct effect of melatonin on the predicted targets by using qPCR.

Results

We identified 8 potential target genes by network pharmacology analysis. Enrichment analysis suggests that melatonin may treat periodontitis by inhibiting the expression of three potential targets (MPO, MMP8, and MMP9). Molecular docking results showed that melatonin could effectively bind to MMP8 and MMP9. Subsequently, melatonin was further validated in a mouse LIP model to inhibit the expression of MPO, MMP8, and MMP9 in the periodontal tissue. Finally, we verified the direct effect of melatonin on the mRNA expression of MPO, MMP8, and MMP9 in an in vitro cellular model.

Conclusions

Through a combination of network pharmacology and experimental validation, this study provides a more comprehensive understanding of the mechanism of melatonin to treat periodontitis. Our study suggests that MPO, MMP8, and MMP9 as key target genes of melatonin to treat periodontitis. These findings present a more comprehensive basis for further investigation into the mechanisms of pharmacological treatment of periodontitis by melatonin.

Injectable hydrogels activated with copper sulfide nanoparticles for enhancing spatiotemporal sterilization and osteogenesis in periodontal therapy

Developing biomaterials capable of promoting bone regeneration in bacteria-infected sites is of utmost urgency for periodontal disease therapies. Here we produce a hybrid hydrogel by integrating CuS nanoparticles (CuSNPs), which could kill bacteria through photothermal therapy (PTT) triggered by a near infrared (NIR) light, and a gelatin methacryloyl (GelMA) hydrogel, which is injectable and biocompatible. Specifically, CuSNPs were precipitated by chitosan (CS) firstly, then grafted with methacrylic anhydride (MA) to form CuSNP@CS-MA, which was photo-crosslinked with GelMA to synthesize hybrid hydrogels (GelMA/CuSNP). The hybrid hydrogels exhibited a broad-spectrum antibacterial property that could be spatiotemprorally manipulated through applying a NIR light. Their mechanical properties were adjustable by controlling the concentration of CuSNPs, enabling the hydrogels to become more adapted to the oral diseases. Meanwhile, the hybrid hydrogels showed good cytocompatibility in vitro and improved hemostasis in vivo. Moreover, they accelerated alveolar osteogenesis and vascular genesis, successfully treating periodontis in four weeks in a rat model. GelMA/CuSNP hydrogels showed a broad-spectrum sterilization ability via PTT in vitro and outstanding antibacterial property in vivo, suggesting that the hybrid hydrogels could function in the challenging, bacteria-rich, oral environment. Such injectable hybrid hydrogels, capable of achieving both facilitated osteogenesis and NIR-inducible sterilization, represent a new biomaterial for treating periodontitis.

Effect of mandibular advancement appliance use on oral and periodontal health in patients with OSA: a systematic review

STUDY OBJECTIVES

Use of a mandibular advancement appliance (MAA) is an effective treatment option for mild-to-moderate obstructive sleep apnea (OSA). MAA is well-tolerated but undesirable effects may be observed over time. The present systematic review aimed to assess the effect of MAA use on oral and periodontal health in patients with OSA.

METHODS

MEDLINE (PubMed), Cochrane, and Scopus were searched for randomized and non-randomized controlled trials (RCTs, NRCTs), cohorts, and case-control studies reporting on side effects of MAA treatment in OSA patients during a follow-up of at least 6 months.

RESULTS

From a total of 169 articles screened, 28 were selected. The most frequently reported MAA-related effects on oral health were: hypersalivation (weighted mean prevalence, 33.3%), occlusal changes (30.2%), muscle pain (22.9%), tooth discomfort or pain (20.2%), and xerostomia (18.3%). No MAA-related periodontal effect was reported. The periodontal status prior to MAA treatment was rarely assessed and described, but 5 studies (17.8%) stated that periodontitis was an exclusion criterion for MAA. Only one retrospective study specifically evaluated periodontal parameters and reported no significant changes in periodontally healthy patients with OSA using MAA for over 7 years.

CONCLUSION

MAA use is associated with a number of clinical consequences on oral health, but there is no evidence to conclude whether or not MAA affects periodontal health in patients with OSA. This aspect appears to be under-evaluated and should be further investigated in relation to the type of MAA, the duration of treatment, and prior history of periodontitis.

Clinical Research on the Safety Evaluation of Platelet-rich Plasma Treatment in Oral Diseases: A Study Protocol

Background

Platelet-rich plasma (PRP) is a biological product obtained from autologous blood that contains growth factors, promoting the healing and regeneration of human tissues. Several oral diseases require surgical intervention, producing residual wounds that undergo a healing process, accompanied by pain, swelling, superinfections, and bone remodeling. This protocol study aims to evaluate the safety of PRP use for the following dental procedures: post-extraction socket healing, periodontal tissue regeneration, maxillary sinus floor elevation, tooth transplantation, and intentional tooth replantation.

Methods

Ten patients will be enrolled and subjected to the required treatment with the addition of PRP, after appropriate hematological and biochemical evaluations. The participants will then be subjected to an observation period of 4 weeks to monitor adverse events through clinical observation. Secondary outcomes will regard pain, and clinical evolution of the treated site. Among these, presence of infection, swelling, wound healing, stability of the transplanted tooth.

Discussion

Safety of medical procedures represents the first requirement for their introduction in routine practice. A careful evaluation of clinical response during follow-up period and registration of adverse effects is fundamental for safety confirmation and subsequent use of PRP for the proposed dental procedures.

Trial registration

Japan Registry of Clinical Trials (https://jrct.niph.go.jp/, registry number: jRCTc030190273, jRCTc030190274, jRCTc030190275, jRCTc030190276, jRCTc030190277; Date of registration: 31 March 2020).

Prevalence of periodontitis in dentate people between 2011 and 2020: A systematic review and meta-analysis of epidemiological studies

AIM

The aim of the study was to evaluate the prevalence of periodontitis in dentate people between 2011 and 2020.

MATERIALS AND METHODS

PUBMED, Web of Science, and LILACS were searched up to and including December 2021. Epidemiological studies reporting the prevalence of periodontitis conducted between 2011 and 2020 were eligible for inclusion in this review. Studies were grouped according to the case definition of confidence as confident (Centers for Disease Control [CDC] AAP 2012; CDC/AAP 2007; and Armitage 1999) and non-confident (community periodontal index of 3 or 4, periodontal pocket depth >4 mm, and clinical attachment level ≥1 mm). Random effects meta-analyses with double arcsine transformation were conducted. Sensitivity subgroup and meta-regression analyses explored the effect of confounding variables on the overall estimates.

RESULTS

A total 55 studies were included. The results showed a significant difference, with confident case definitions (61.6%) reporting nearly twice the prevalence as non-confident classifications (38.5%). Estimates using confident periodontal case definitions showed a pooled prevalence of periodontitis of 61.6%, comprising 17 different countries. Estimates reporting using the CDC/AAP 2012 case definition presented the highest estimate (68.1%) and the CDC/AAP 2007 presented the lowest (48.8%). Age was a relevant confounding variable, as older participants (≥65 years) had the highest pooled estimate (79.3%).

CONCLUSION

Between 2011 and 2020, periodontitis in dentate adults was estimated to be around 62% and severe periodontitis 23.6%. These results show an unusually high prevalence of periodontitis compared to the previous estimates from 1990 to 2010.