Periodontitis, a prevalent chronic inflammatory disease caused by bacteria, poses a significant challenge to current treatments by merely slowing their progression. Herein, we propose an innovative solution in the form of hierarchical nanostructured 3D printed bilayer membranes that serve as dual-drug delivery nanoplatforms and provide scaffold function for the regeneration of periodontal tissue. Nanocomposite hydrogels were prepared by combining lipid nanoparticle-loaded grape seed extract and simvastatin, as well as chitin nanocrystals, which were then 3D printed into a bilayer membrane that possesses antimicrobial properties and multiscale porosity for periodontal tissue regeneration. The constructs exhibited excellent mechanical properties by adding chitin nanocrystals and provided a sustained release of distinct drugs over 24 days. We demonstrated that the bilayer membranes are cytocompatible and have the ability to induce bone-forming markers in human mesenchymal stem cells, while showing potent antibacterial activity against pathogens associated with periodontitis. In vivo studies further confirmed the efficacy of bilayer membranes in enhancing alveolar bone regeneration and reducing inflammation in a periodontal defect model. This approach suggests promising avenues for the development of implantable constructs that not only combat infections, but also promote the regeneration of periodontal tissue, providing valuable insights into advanced periodontitis treatment strategies.

Bioactive ceramics, primarily consisting of bioactive glasses, glass-ceramics, calcium orthophosphate ceramics, calcium silicate ceramics and calcium carbonate ceramics, have received great attention in the past decades given their biocompatible nature and excellent bioactivity in stimulating cell proliferation, differentiation and tissue regeneration. Recent studies have tried to combine bioactive ceramics with bioactive ions, polymers, bioactive proteins and other chemicals to improve their mechanical and biological properties, thus rendering them more valid in tissue engineering scaffolds. This review presents the beneficial properties and potential applications of bioactive ceramic-based materials in dentistry, particularly in the repair and regeneration of dental hard tissue, pulp-dentin complex, periodontal tissue and bone tissue. Moreover, greater insights into the mechanisms of bioactive ceramics and the development of ceramic-based materials are provided.
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Understanding patient responses to periodontal regeneration is crucial. This systematic review and meta-analysis addressed two key questions: (a) the impact of periodontal regeneration on patient-reported outcome measures (PROMs) for intrabony and furcation involvement and (b) the cost-effectiveness of periodontal regeneration for treating periodontal defects. Twenty-four studies were included, with 20 randomized clinical trials (RCTs) reporting patient-reported outcomes and five (three RCTs and two economic model-based studies) reporting cost-effectiveness outcomes. Results favored regeneration therapy over conventional flap surgery for intrabony defects, showing improvements in qualitative (i.e., amount of regenerated attachment apparatus) and quantitative parameters (i.e., probing and radiographic parameters). In terms of PROMs, regenerative treatments involving barrier membranes resulted in longer chair times and higher rates of complications (such as membrane exposure or edema) compared to flap with biologic agents or access flap alone. Despite this, oral health-related quality of life improved after both regenerative and extraction procedures. Economically, regeneration remained favorable compared to extraction and replacement or open flap debridement alone for periodontal defects. Single-flap variants in open flap debridement yielded similar outcomes to regenerative treatment, offering a potentially cost-effective option. Nevertheless, further discussion on the benefits of less-invasive flap designs is needed due to the lack of histological evaluation.

Inflammation caused by a bacterial infection and the subsequent dysregulation of the host immune-inflammatory response are detrimental to periodontal regeneration. Herein, we present an infection-sensitive scaffold prepared by layer-by-layer assembly of Feraheme-like superparamagnetic iron oxide nanoparticles (SPIONs) on the surface of a three-dimensional-printed polylactic-co-glycolic acid (PLGA) scaffold. The SPION/PLGA scaffold is magnetic, hydrophilic, and bacterial-adhesion resistant. As indicated by gene expression profiling and confirmed by quantitative real-time reverse transcription polymerase chain reaction and flow cytometry analysis, the SPION/PLGA scaffold facilitates macrophage polarization toward the regenerative M2 phenotype by upregulating IL-10, which is the molecular target of repair promotion, and inhibits macrophage polarization toward the proinflammatory M1 phenotype by downregulating NLRP3, which is the molecular target of anti-inflammation. As a result, macrophages modulated by the SPS promote osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) in vitro. In a rat periodontal defect model, the SPION/PLGA scaffold increased IL-10 secretion and decreased NLRP3 and IL-1β secretion with Porphyromonas gingivalis infection, achieving superior periodontal regeneration than the PLGA scaffold alone. Therefore, this antibacterial SPION/PLGA scaffold has anti-inflammatory and bacterial antiadhesion properties to fight infection and promote periodontal regeneration by immunomodulation. These findings provide an important strategy for developing engineered scaffolds to treat periodontal defects.

We report the successful treatment of multiple recession type (RT) 3 gingival recessions in periodontally compromised mandibular anterior teeth with limited keratinized tissue. A 35-yearold man with stage III, grade C periodontitis underwent a two-stage intervention. Initially, a modification of the connective tissue graft (m-CTG) wall technique was used as part of phenotype modification therapy. The CTG acted as a protective \'wall,\' securing space for periodontal regeneration, enhancing root coverage, soft tissue thickness, and keratinized mucosal width. Recombinant human fibroblast growth factor-2 and carbonate apatite promoted periodontal regeneration. This procedure successfully facilitated periodontal regeneration, resulting in the transition from RT3 to RT2 gingival recession and adequate keratinized mucosal width. Eighteen months later, the second surgery used a tunneled coronally advanced flap (TCAF) for root coverage. TCAF involved combining a coronally advanced flap and tunnel technique by elevating the trapezoidal surgical papilla and using a de-epithelialized CTG inserted beneath the tunneled flap. Root conditioning with ethylenediaminetetraacetic acid and enamel matrix derivative gel application were performed. Consequently, mean CAL gain was 5.3 mm, mean root coverage was 4.5 mm in height, and the gingival phenotype improved at the treated sites by the 12-month follow-up. This staged approach addresses the challenges of treating RT3 gingival recession with promising outcomes.

The intricate nature of oral-maxillofacial structure and function, coupled with the dynamic oral bacterial environment, presents formidable obstacles in addressing the repair and regeneration of oral-maxillofacial bone defects. Numerous characteristics should be noticed in oral-maxillofacial bone repair, such as irregular morphology of bone defects, homeostasis between hosts and microorganisms in the oral cavity and complex periodontal structures that facilitate epithelial ingrowth. Therefore, oral-maxillofacial bone repair necessitates restoration materials that adhere to stringent and specific demands. This review starts with exploring these particular requirements by introducing the particular characteristics of oral-maxillofacial bones and then summarizes the classifications of current bone repair materials in respect of composition and structure. Additionally, we discuss the modifications in current bone repair materials including improving mechanical properties, optimizing surface topography and pore structure and adding bioactive components such as elements, compounds, cells and their derivatives. Ultimately, we organize a range of potential optimization strategies and future perspectives for enhancing oral-maxillofacial bone repair materials, including physical environment manipulation, oral microbial homeostasis modulation, osteo-immune regulation, smart stimuli-responsive strategies and multifaceted approach for poly-pathic treatment, in the hope of providing some insights for researchers in this field. In summary, this review analyzes the complex demands of oral-maxillofacial bone repair, especially for periodontal and alveolar bone, concludes multifaceted strategies for corresponding biomaterials and aims to inspire future research in the pursuit of more effective treatment outcomes.

OBJECTIVE: This study aimed to investigate the temporal and spatial changes in the expression of periostin during periodontal inflammation in mice.
METHODS: A periodontitis model was constructed using silk thread ligation. Mice were randomly divided into five groups including control group, 4-day ligation group, 7-day ligation group, 14-day ligation group, and self-healing group (thread removal for 14 days after 14-day ligation). Micro-CT and histological staining were performed to characterize the dynamic changes in the mouse periodontal tissue in each group. RNAscope and immunohistochemical staining were used to analyze the pattern of changes in periostin at various stages of periodontitis. The cell experiment was divided into three groups: control group, lipopolysaccharide (LPS) stimulation group (treated with LPS for 12 h), and LPS stimulation removal group (treated with LPS for 3 h followed by incubation with medium for 9 h). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of periostin, transforming growth factor-β1 (TGF-β1), and matrix metalloproteinase 2 (MMP2).
RESULTS: Significant alveolar bone resorption was observed 7 days after ligation. With increasing duration of ligation, the damage to the mouse periodontal tissue was aggravated, which manifested as increased osteoclasts, widening of the periodontal membrane space, and decreased alveolar bone height. Some degree of periodontal tissue repair was observed in the self-healing group. Periostin expression decreased at 4 and 7 days compared with the control group and increased at 14 days compared with 4 and 7 days. A significant recovery was found in the self-healing group. The qRT-PCR results showed that the expression of periostin and TGF-β1 in the LPS stimulation group decreased compared with that in the control group but significantly recovered in the LPS removal group.
CONCLUSIONS: Periostin expression in the PDL of mice showed a downward and upward trend with inflammation progression. The significant recovery of periostin expression after removing inflammatory stimuli may be related to TGF-β1, which is crucial to maintain the integrity of the PDL.
目的: 研究小鼠牙周炎进程中骨膜蛋白表达的时空变化规律。方法: 采用丝线结扎法构建小鼠牙周炎模型。设置对照组、栓丝4 d组、栓丝7 d组、栓丝14 d组、自愈组（栓丝14 d再去除丝线14 d），通过Micro-CT、组织学染色观察各组小鼠牙周组织的动态变化特征，利用RNAscope、免疫组织化学染色分析牙周膜内骨膜蛋白在牙周炎进程不同阶段的变化规律。培养人牙周膜细胞并随机分为对照组、脂多糖（LPS）刺激组（LPS处理12 h）、去除LPS刺激组（LPS处理3 h后再用培养基培养9 h），实时定量聚合酶链反应（qRT-PCR）检测骨膜蛋白、转化生长因子β1（TGF-β1）、基质金属蛋白酶2（MMP2）的表达。结果: 栓丝7 d组可见明显的牙槽骨吸收，栓丝14 d组牙周组织破坏加重，表现为破骨细胞增多、牙周膜间隙增宽、牙槽骨高度降低，而自愈组见一定程度的牙周组织修复。与对照组相比，栓丝4 d组、栓丝7 d组牙周膜内骨膜蛋白表达降低，栓丝14 d组骨膜蛋白表达相较于栓丝4 d组及栓丝7 d组增加，自愈组骨膜蛋白表达与对照组相似。qRT-PCR结果显示，LPS刺激组与对照组相比骨膜蛋白、TGF-β1的表达均下降，而去除LPS刺激组与LPS刺激组相比骨膜蛋白、TGF-β1的表达均升高。结论: 小鼠牙周膜内骨膜蛋白表达随炎症进展呈先下降后回升的趋势，去除炎症刺激后骨膜蛋白表达的恢复可能与TGF-β1表达上调有关。.

Regenerating periodontal defects in osteoporosis patients presents a significant clinical challenge. Unlike the relatively straightforward regeneration of homogeneous bone tissue, periodontal regeneration requires the intricate reconstruction of the cementum-periodontal ligament-alveolar bone interface. Strontium (Sr)-doped biomaterials have been extensively utilized in bone tissue engineering due to their remarkable pro-osteogenic attributes. However, their application in periodontal tissue regeneration has been scarcely explored. In this study, we synthesized an innovative injectable Sr-BGN/GNM scaffold by integrating Sr-doped bioactive glass nanospheres (Sr-BGNs) into the nanofiber architecture of gelatin nanofiber microspheres (GNMs). This design, mimicking the natural bone extracellular matrix (ECM), enhanced the scaffold\'s mechanical properties and effectively controlled the sustained release of Sr ions (Sr2+), thereby promoting the proliferation, osteogenic differentiation, and ECM secretion of PDLSCs and BMSCs, as well as enhancing vascularization in endothelial cells. In vivo experiments further indicated that the Sr-BGNs/GNMs significantly promoted osteogenesis and angiogenesis. Moreover, the scaffold\'s tunable degradation kinetics optimized the prolonged release and pro-regenerative effects of Sr2+ in vivo, matching the pace of periodontal regeneration and thereby facilitating the regeneration of functional periodontal tissues under osteoporotic conditions. Therefore, Sr-BGNs/GNMs emerge as a promising candidate for advancing periodontal regeneration strategies.

OBJECTIVE: To compare the regenerative clinical and radiographic effects of cross-linked hyaluronic acid (xHyA) with enamel matrix proteins (EMD) at six months after regenerative treatment of periodontal intrabony defects.
METHODS: Sixty patients presenting one intrabony defect each were randomly assigned into control (EMD) and test (xHyA) groups. Clinical attachment level (CAL) gain was the primary outcome, while pocket probing depth (PPD), gingival recession (REC), bleeding on probing (BOP), full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), and radiographic parameters such as defect depth (BC-BD), and defect width (DW) were considered secondary outcome variables. Parameters were recorded at baseline and after 6 months.
RESULTS: At the 6-month follow-up, 54 patients were available for statistical analysis. In the control and test groups, the mean CAL gain was statistically significant in the intragroup comparison (p < 0.001). 48.1% of test sites showed a CAL gain ≤ 2 mm compared with 33.3% of control sites. The mean PPD reduction was statistically significant in the intragroup comparison in both groups (p < 0.001). The mean REC increase was similar in the two groups: 1.04 ± 1.29 mm vs 1.11 ± 1.22 mm (test vs control). The mean BC-BD, DW, FMPS, FMBS, and BOP changed statistically significantly only in the intragroup comparison, not in the intergroup comparison.
CONCLUSIONS: Both treatments, EMD and xHyA, produced similar statistically significant clinical and radiographical improvements after six months when compared with baseline.

Aim Allografts, autografts, alloplast and xenografts are frequently used for periodontal regeneration. The aim of this study was to determine the efficacy of advanced platelet-rich fibrin (A-PRF) in combination with demineralized freeze-dried bone allograft (DFDBA) and DFDBA alone in periodontal infrabony defects. Methodology This was a split-mouth design study where 20 infrabony defects in 10 patients were included. Patients were randomly divided into two groups, where DFDBA allograft and A-PRF were used in the test group, while the DFDBA allograft alone was used in the control group. Furthermore, the results were evaluated at baseline, three, and nine months, respectively, in terms of clinical and radiographic parameters. Data were analysed with an unpaired t-test at the significance level of P < 0.05 (statistically significant). Results Both treatments showed reduced clinical and radiographic parameters from baseline to nine months. There was a non-significant difference in the plaque index (PI), bleeding on probing (BOP), clinical attachment level (CAL), and radiographic defect fill (RDF). In comparison to the control group (3.40 ± 0.516), the probing pocket depth (PPD) in the test group at nine months (3.22 ± 0.422) was statistically significant showing reduction in the PPD (P = 0.042). Conclusion Within its limitations, the study showed that A-PRF plus DFDBA and DFDBA alone treatment modalities reduced clinical and radiographic parameters from baseline, at 9 months; however, the inclusion of A-PRF did not substantially improve the treatment outcome when comparing both the groups, except for the probing pocket depth after nine months.