BACKGROUND: Effective treatments for the alveolar bone defect remain a major concern in dental therapy. The objectives of this study were to develop a fibrin and konjac glucomannan (KGM) composite hydrogel as scaffolds for the osteogenesis of nasal mucosa-derived ectodermal mesenchymal stem cells (EMSCs) for the regeneration of alveolar bone defect, and to investigate the osteogenesis-accelerating effects of black phosphorus nanoparticles (BPNs) embedded in the hydrogels.
METHODS: Primary EMSCs were isolated from rat nasal mucosa and used for the alveolar bone recovery. Fibrin and KGM were prepared in different ratios for osteomimetic hydrogel scaffolds, and the optimal ratio was determined by mechanical properties and biocompatibility analysis. Then, the optimal hydrogels were integrated with BPNs to obtain BPNs/fibrin-KGM hydrogels, and the effects on osteogenic EMSCs in vitro were evaluated. To explore the osteogenesis-enhancing effects of hydrogels in vivo, the BPNs/fibrin-KGM scaffolds combined with EMSCs were implanted to a rat model of alveolar bone defect. Micro-computed tomography (CT), histological examination, real-time quantitative polymerase chain reaction (RT-qPCR) and western blot were conducted to evaluate the bone morphology and expression of osteogenesis-related genes of the bone regeneration.
RESULTS: The addition of KGM improved the mechanical properties and biodegradation characteristics of the fibrin hydrogels. In vitro, the BPNs-containing compound hydrogel was proved to be biocompatible and capable of enhancing the osteogenesis of EMSCs by upregulating the mineralization and the activity of alkaline phosphatase. In vivo, the micro-CT analysis and histological evaluation demonstrated that rats implanted EMSCs-BPNs/fibrin-KGM hydrogels exhibited the best bone reconstruction. And compared to the model group, the expression of osteogenesis genes including osteopontin (Opn, p < 0.0001), osteocalcin (Ocn, p < 0.0001), type collagen (Col , p < 0.0001), bone morphogenetic protein-2 (Bmp2, p < 0.0001), Smad1 (p = 0.0006), and runt-related transcription factor 2 (Runx2, p < 0.0001) were all significantly upregulated.
CONCLUSIONS: EMSCs/BPNs-containing fibrin-KGM hydrogels accelerated the recovery of the alveolar bone defect in rats by effectively up-regulating the expression of osteogenesis-related genes, promoting the formation and mineralisation of bone matrix.

Developing effective methods for alveolar bone defect regeneration is a significant challenge in orthopedics. Exosomes from human umbilical cord mesenchymal stem cells (HUMSC-Exos) have shown potential in bone repair but face limitations due to undefined application methods and mechanisms. To address this, HUMSC-Exos were encapsulated in polyvinyl alcohol (PVA) hydrogel (Exo@PVA) to create a novel material for alveolar bone repair. This combination enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) more effectively than Exos alone. Additionally, Exo@PVA significantly improved alveolar bone regeneration and defect repair in rats. The microRNA-21-5p (miR-21-5p) in Exo@PVA, identified through the GEO database and analyzed via in silico methods, played a crucial role. miR-21-5p promoted BMSC osteogenic differentiation by inhibiting WWP1-mediated KLF5 ubiquitination and enhanced HUVEC angiogenesis by targeting ATP2B4. These findings underscore the potential of an Exo-based approach with PVA hydrogel scaffolds for bone defect repair, operating through the miR-21-5p/WWP1/ATP2B4 signaling axis.

The rehabilitation of alveolar bone defects of moderate to severe size is often challenging. Currently, the therapeutic approaches used include, among others, the guided bone regeneration technique combined with various bone grafts. Although these techniques are widely applied, several limitations and complications have been reported such as morbidity, suboptimal graft/membrane resorption rate, low structural integrity, and dimensional stability. Thus, the development of biomimetic scaffolds with tailor-made characteristics that can modulate cell and tissue interaction may be a promising tool. This article presents a critical consideration in scaffold\'s design and development while also providing information on various fabrication methods of these nanosystems. Their utilization as delivery systems will also be mentioned.

UNASSIGNED: Reconstruction of alveolar bone defects resulting from aging, trauma, ablative surgery or pathology, remains a significant clinical challenge. The objective of this study was to investigate the antibacterial and antifungal activities of mixed polymethylmethacrylate-hydroxyapatite (PMMA-HA) against oral microorganisms. Our findings could provide valuable insights into the prospective application of PMMA-HA as a synthetic bone graft material to manage alveolar bone defects via tissue engineering.
UNASSIGNED: HA powder was obtained from the Center for Ceramics in Indonesia and PMMA granules were obtained from HiMedia Laboratories; these were prepared in 20:80, 30:70, and 40:60 ratios. The antibacterial diffusion method was then performed against Staphylococcusaureus, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Fusobacterium nucleatum, while the antifungal diffusion method was used to test against Candida albicans. Standardized protocols were used for microbial culturing and inhibition zones were measured with digital calipers. Statistical analyses included one-way ANOVA and Kruskal-Wallis tests, supplemented by post-hoc Tukey HSD tests.
UNASSIGNED: A PMMA-HA scaffold with a 20:80 ratio demonstrated the highest antibacterial activity against S. aureus, A. actinomycetemcomitans, P. gingivalis, and F. nucleatum. This was followed by the 30:70 and 40:60 ratios in terms of antibacterial activity. Statistical significance was achieved with p < 0.05 in comparison to controls. However, none of the PMMA-HA ratios showed antifungal activity against C. albicans.
UNASSIGNED: PMMA-HA scaffolds have significant activity against bacteria, but not against fungi.
UNASSIGNED: الحنك المشقوق هو عيب خلقي شائع يتطلب غالبا ترقيع العظام السنخية للحصول على علاج فعال. كان الهدف من هذه الدراسة هو دراسة الأنشطة المضادة للبكتيريا والفطريات لمختلط بولي ميثيل ميثاكريلات-هيدروكسيباتيت ضد الكائنات الحية الدقيقة في الفم. يمكن أن تفيد النتائج الاستخدام المحتمل لـ بولي ميثيل ميثاكريلات-هيدروكسيباتيت كمواد تطعيم عظمية اصطناعية لعلاج عيوب العظام السنخية في حالات الحنك المشقوق.
UNASSIGNED: تم تحضير مسحوق هيدروكسيباتيت من مركز السيراميك في إندونيسيا وحبيبات بولي ميثيل ميثاكريلات من مختبرات هاي ميديا بنسبة 20:80 و30:70 و40:60. تم استخدام طريقة الانتشار المضاد للبكتيريا ضد المكورات العنقودية الذهبية، المشعشعة المصاحبة للورم الفطري، وحيدات الخلية البورفيرينية اللثوية و المغزلية الناخرة، في حين تم اختبار طريقة الانتشار المضاد للفطريات ضد المبيضات البيضاء. استخدمت بروتوكولات موحدة للزراعة الميكروبية. تم قياس مناطق التثبيط باستخدام الفرجار الرقمي. وشملت التحليلات الإحصائية اختبارات أنوفا و كروسكال-واليس أحادية الاتجاه، بالإضافة إلى اختبارات \"تركي الفرق الكبير بصراحة\" اللاحقة.
UNASSIGNED: أظهرت سقالة بولي ميثيل ميثاكريلات-هيدروكسيباتيت بنسبة 20:80 أعلى نشاط مضاد للجراثيم ضد المكورات العنقودية الذهبية، المشعشعة المصاحبة للورم الفطري، وحيدات الخلية البورفيرينية اللثوية و المغزلية الناخرة. وتلاها النسب 30:70 و40:60 من حيث النشاط المضاد للبكتيريا. تم تحقيق أهمية إحصائية بالمقارنة مع الضوابط. ومع ذلك، لم تظهر أي من نسب بولي ميثيل ميثاكريلات-هيدروكسيباتيت نشاطا مضادا للفطريات ضد المبيضات البيضاء.
UNASSIGNED: سقالات بولي ميثيل ميثاكريلات-هيدروكسيباتيت لها نشاط مضاد للجراثيم، ولكن ليس لها نشاط مضاد للفطريات.

BACKGROUND: Alveolar bone defects, particularly palatal bone dehiscence (PBD) and labial bone fenestration (LBF), occur frequently as a result of retraction of the maxillary anterior teeth. The study aims to explore the long-term bone remodeling of maxillary anterior teeth in adult patients with post-orthodontic treatment PBD and LBF.
METHODS: The study includes 24 adult patients with maxillary protrusion (8 males, 16 females) who were treated with extraction of four first premolars and had alveolar bone defects (PBD or LBF) in maxillary anterior teeth following orthodontic treatment. Cone-beam computed tomography imaging measurements were obtained before (T1), after (T2) orthodontic treatment, and after at least 1-year removable thermoplastic retainer retention (T3). The maxillary anterior teeth with PBD or LBF at T2 were divided into the PBD or LBF groups, respectively. The labial and palatal alveolar bone height (ABH), alveolar bone thickness (ABT), and movement of maxillary anterior teeth were measured during retraction (T2-T1) and retention (T3-T2) periods.
RESULTS: The incidence of PBD and LBF in maxillary anterior teeth significantly increased after orthodontic treatment and decreased during the retention period. In the PBD group, the palatal ABH of all maxillary anterior teeth significantly increased from T1 to T2 but decreased from T2 to T3. The ABT of the maxillary central incisor and canine significantly increased on the palatal side and decreased on the labial side during the retention period. In the LBF group, the labial ABT of the maxillary central incisor at the apical level showed a significant decrease from T1 to T2, followed by an increase from T2 to T3. In both groups, the maxillary central incisor showed significant labial movement, with a relative intrusion during the retention period.
CONCLUSIONS: For adult patients with maxillary protrusion, the alveolar bone defect of maxillary anterior teeth caused by orthodontic retraction significantly improved during the retention period, indicating good long-term bone remodeling. Our findings suggest that a combination of spontaneous reorientation of maxillary anterior teeth and bone remodeling contributed to alveolar bone covering in these patients.

The efficiency of bone tissue regeneration by decellularized tooth matrix, demineralized tooth matrix, and commercial xenograft Bio-Oss Spongiosa was compared on the model of a critical-size circular defect in the alveolar bone of the upper jaw of adult Wistar rats. The defect healing dynamics was assessed using histological, histomorphometrical, and immunohistochemical methods on days 30 and 60. In contrast to demineralized matrix and commercial xenograft, decellularized matrix induces the formation of the new bone tissue by day 60. Decellularized matrix can be considered as a biomaterial for cell-free tissue engineering for alveolar bone restoration in dentistry and maxillofacial surgery.

This study aimed to assess effects of 3-dimensionally (3D) printed poly-d,l-lactin (PDLLA) on human alveolar bone-derived mesenchymal stem cell (h-ABMSC) osteogenic proliferation and differentiation. Human ABMSCs were cultured and identified using flow cytometry and morphological analysis. Control and PDLLA experimental groups were assessed using a Cell Counting Kit-8 (CCK-8) to detect cellular cytotoxicity and proliferative activity. Real-time quantitative polymerase chain reaction was used to determine expression levels of osteogenesis genes including alkaline phosphatase (ALP), Runt-related transcription factor 2 (Runx-2), osteopontin (OPN), and osteocalcin (OCN). The results showed that h-ABMSCs were successfully cultured and revealed by microscopic observation. Human ABMSCs were spindle-shaped, with clustered and fish-like primary cells. Cell surface markers were negative for CD34 and positive for CD44 and CD90. PDLLA had no cytotoxicity. Human ABMSCs proliferated normally, and osteogenic differentiation of the cells was observed on the surface of PDLLA. Cellular proliferative activity and expression levels of osteogenesis-related genes of PDLLA and control groups showed no significant difference, including ALP, Runx-2, OPN, and OCN. These results suggest that 3D-printed PDLLA has good cell compatibility and biological activity.

UNASSIGNED: The study was aimed to compare and evaluate the clinical and radiographic outcomes of injectable platelet-rich fibrin (i-PRF) polymerized with hydroxyapatite (HA) bone graft and HA bone graft alone for treating three-wall intrabony defects (IBDs).
UNASSIGNED: The trial was planned as a randomized, prospective clinico-radiographic study with inclusion of 34 three-wall IBDs in patients with stage III periodontitis. IBDs were assigned randomly to one of the groups, i.e., Group I - experimental (i-PRF + HA) and Group II - control (HA alone). At baseline and 6 and 9-month intervals, both the clinical and radiographic measurements were taken and baseline and 9-month data were tabulated and imported into SPSS 22 software. Student unpaired and paired t- tests were used to find significant differences (p<0.05).
UNASSIGNED: Both the groups showed substantial changes in all clinical and radiographic measures on comparison from baseline values. On intergroup comparison, the i-PRF + HA group reported significantly higher original defect resolution and original defect fill as compared to the HA group.
UNASSIGNED: i-PRF polymerized with HA graft has shown better results as compared to HA graft alone in three-wall IBDs and therefore can be used as a better possible alternative for the treatment of three-wall IBDs.

Pluronic F127 (PF127) hydrogel has been highlighted as a promising biomaterial for bone regeneration, but the specific molecular mechanism remains largely unknown. Herein, we addressed this issue in a temperature-responsive PF127 hydrogel loaded with bone marrow mesenchymal stem cells (BMSCs)-derived exosomes (Exos) (PF127 hydrogel@BMSC-Exos) during alveolar bone regeneration. Genes enriched in BMSC-Exos and upregulated during the osteogenic differentiation of BMSCs and their downstream regulators were predicted by bioinformatics analyses. CTNNB1 was predicted to be the key gene of BMSC-Exos in the osteogenic differentiation of BMSCs, during which miR-146a-5p, IRAK1, and TRAF6 might be the downstream factors. Osteogenic differentiation was induced in BMSCs, in which ectopic expression of CTNNB1 was introduced and from which Exos were isolated. The CTNNB1-enriched PF127 hydrogel@BMSC-Exos were constructed and implanted into in vivo rat models of alveolar bone defects. In vitro experiment data showed that PF127 hydrogel@BMSC-Exos efficiently delivered CTNNB1 to BMSCs, which subsequently promoted the osteogenic differentiation of BMSCs, as evidenced by enhanced ALP staining intensity and activity, extracellular matrix mineralization (p < 0.05), and upregulated RUNX2 and OCN expression (p < 0.05). Functional experiments were conducted to examine the relationships among CTNNB1, microRNA (miR)-146a-5p, and IRAK1 and TRAF6. Mechanistically, CTNNB1 activated miR-146a-5p transcription to downregulate IRAK1 and TRAF6 (p < 0.05), which induced the osteogenic differentiation of BMSCs and facilitated alveolar bone regeneration in rats (increased new bone formation and elevated BV/TV ratio and BMD, all with p < 0.05). Collectively, CTNNB1-containing PF127 hydrogel@BMSC-Exos promote the osteogenic differentiation of BMSCs by regulating the miR-146a-5p/IRAK1/TRAF6 axis, thus inducing the repair of alveolar bone defects in rats.

Radiographic determination of the bone level is useful in the diagnosis and determination of the severity of the periodontal disease. Various two- and three-dimensional imaging modalities offer choices for imaging pathologic processes that affect the periodontium. In recent years, innovative computer techniques, especially artificial intelligence (AI), have begun to be used in many areas of dentistry and are helping increase treatment and diagnostic performance. This study was aimed at developing a machine-learning (ML) model and assessing the extent to which it was capable of classifying periodontal defects on 2D periapical images. Eighty-seven periapical images were examined as part of this research. The existence or absence of periodontal defects in the aforementioned images were evaluated by a human observer. The evaluations were subsequently repeated using a radiomics platform. A comparison was made of all data acquired through human observation and ML techniques by SVM analysis. According to the study findings the ability of human observers and the ML model to detect periodontal defects was significantly different in comparison to the gold standard. However, ML and human observers performed similarly for the detection of periodontal defects without a significant difference. This study reveals that the prediction of periodontal defects can be achieved by combining particular radiomic features with image variables. The proposed machine leaning model can be utilized for supporting clinical practitioners and eventually substitute evaluations conducted by human observers while enhancing future levels of performance.