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Journal of Periodontal Research Oct 2023This study aimed to investigate (1) the temporal pattern of ferroptosis, an iron-dependent cell death, in ligation-induced rat periodontitis and (2) the effect of...
OBJECTIVE
This study aimed to investigate (1) the temporal pattern of ferroptosis, an iron-dependent cell death, in ligation-induced rat periodontitis and (2) the effect of ferrostatin-1, a ferroptosis inhibitor, on the model.
BACKGROUND
Ferroptosis may contribute to various diseases. However, the role of ferroptosis in periodontitis is still fully understood.
METHODS
In the first experiment, 25 rats with ligation-induced periodontitis were sacrificed on days 0, 1, 2, 7, and 10. Gingivae were obtained to determine tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and ferroptotic biomarkers, including solute carrier family 3 member 2 (SLC3A2) and solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (Gpx4), via immunoblotting. Using microcomputed tomography (μCT) and histology, the periodontal soft and hard tissue lesions, including dental alveolar bone crest level, bony characteristics of the surrounding alveolus, periodontal tissue inflammation, and periodontal tissue losses, were evaluated. In study two, 16 rats with induced periodontitis were grouped according to ferrostatin-1 treatment. The rats were intraperitoneally injected with solvent or ferrostatin-1 (1.5 mg/kg/day) 1 day before ligation and sacrificed on days 7 and 10. Gingival protein changes and periodontal tissue damage were also examined.
RESULTS
In study one, SLC3A2/SLC7A11 and Gpx4 decreased since day 1; however, TNF-α/IL-1β increased on days 7 and 10. Moreover, the μCT/histology revealed resorptive bony characteristics, inflamed gingival tissue, and periodontal attachment loss. In study two, ferrostatin-1-injected rats exhibited significantly increased SLC3A2/SLC7A11 and Gpx4 but decreased TNF-α/IL-1β than vehicle rats. They also revealed lessened bone resorption, tissue inflammation, and attachment loss.
CONCLUSION
This study highlights the role of ferroptosis, via the system Xc/Gpx4 pathway, in experimental periodontitis and may serve as a regulatory strategy.
Topics: Rats; Animals; Ferroptosis; Tumor Necrosis Factor-alpha; X-Ray Microtomography; Periodontitis; Inflammation
PubMed: 37477155
DOI: 10.1111/jre.13165 -
Transfusion Medicine and Hemotherapy :... Aug 2023The application of blood concentrates has gained popularity in dentistry in recent years. Platelet-rich fibrin (PRF) has been discussed frequently due to a high content... (Review)
Review
BACKGROUND
The application of blood concentrates has gained popularity in dentistry in recent years. Platelet-rich fibrin (PRF) has been discussed frequently due to a high content of growth factors and the option of chair-side manufacturing in a simple centrifugation process. PRF is free from adjuvants and inexpensive to produce. The number of studies reporting beneficial effects of PRF in various clinical applications such as alveolar ridge preservation, sinus floor elevation, management and prevention of medical-related osteonecrosis of the jaw, third molar extractions, and guided bone regeneration in dentistry has increased recently. However, to date, neither clinical recommendations nor guidelines are available. The present narrative review aims to summarize the level of evidence on the clinical application of PRF within the field of oral surgery and implantology.
SUMMARY
A literature search in Pubmed and Medline has identified 34 articles as a basis for this narrative review. The effectiveness of the clinical application of PRF has been analyzed for five indications within dentistry: medical-related osteonecrosis of the jaw, wisdom tooth extraction, guided bone regeneration, sinus floor elevation, and alveolar ridge preservation. The amount of data for third molar extractions, socket preservation, and guided bone regeneration is extensive. Less data were available for the use of PRF in combination with sinus floor elevations. There is a lack of studies with scientific evidence on PRF and medical-related osteonecrosis of the jaw; however, studies positively impact patient-related outcome measures. Most studies report on beneficial effects when PRF is additionally applied in intrabony defects. There is no evidence of the positive effects of PRF combined with bone graft materials during sinus floor elevation. However, some benefits are reported with PRF as a sole filling material.
KEY MESSAGES
Many recently published studies show the positive clinical impact of PRF. Yet, further research is needed to ensure the validity of the evidence.
PubMed: 37767284
DOI: 10.1159/000527526 -
Journal of Indian Society of... 2023To analyze through finite element analysis the stress distribution in peri-implant bone tissues, implants, and prosthetic components induced by the socket shield (SS)...
BACKGROUND
To analyze through finite element analysis the stress distribution in peri-implant bone tissues, implants, and prosthetic components induced by the socket shield (SS) technique in comparison to other techniques used to treat tooth loss.
MATERIALS AND METHODS
A three-dimensional model of a superior central incisor crown supported by implant was modeled and three different placement conditions were simulated: SS - 2.0-mm-thick root dentin fragment positioned between the alveolar buccal wall and implant; heterologous bone graft (HBG) - bovine bone graft positioned the alveolar buccal wall and implant; and control (C) - implant fully placed in bone tissue of a healed alveolus. The model was restricted at the lateral surfaces of the bone tissue and the following loads were simulated: Both oblique (45°) loads of 100 N on the lingual surface of the crown (maximal habitual intercuspation) and 25.5 N on the incisal edge of the crown (tooth contact during mandibular protrusion) were simultaneously applied. Tensile stress, shear stress, compression, and displacement were analyzed in the cortical bone, trabecular bone, dentin root fragment, and bone graft; while equivalent von Mises stresses were quantified in the implant and prosthetic components.
RESULTS
Stress values of SS and HBG in the bone tissues were higher than C, while slight differences within models were observed for dentin root fragment, bone graft, implant, and prosthetic components.
CONCLUSIONS
The SS technique presented the highest stress concentration in the peri-implant tissues.
PubMed: 37593548
DOI: 10.4103/jisp.jisp_356_22 -
Frontiers in Immunology 2024
Topics: Tooth Extraction; Bone and Bones
PubMed: 38545105
DOI: 10.3389/fimmu.2024.1394835 -
Anatomical Record (Hoboken, N.J. : 2007) Oct 2023This article provides an ontogenetically-based comparative description of the Guercy 3 partial child's maxilla with Rdm -RM and unerupted RI -RP from Baume Moula-Guercy...
This article provides an ontogenetically-based comparative description of the Guercy 3 partial child's maxilla with Rdm -RM and unerupted RI -RP from Baume Moula-Guercy (MIS 5e) and examines its affinities to European and Middle Eastern Middle-to-Late Pleistocene (≈MIS 14-MIS 1) Homo. Description of the Guercy 3 maxilla and dentition (7.0 year ± 0.9 month) is based on observations of original fossils, casts, CT scans, literature descriptions, and virtual reconstructions. Our ontogenetic sample comprises a Preneanderthal-Neanderthal group and a Homo sapiens group. These groups are subdivided into (1) Preneanderthals (≈MIS 14-9), Early Neanderthals (MIS 7-5e), and Late Neanderthals (MIS 5d-3), and (2) Middle (MIS 5), Upper (MIS 3-2), and Late Upper Paleolithic (≈MIS 1), and recent H. sapiens. Standard techniques were employed for measurements and developmental age determinations.The Guercy 3 maxilla lacks changes found in Late Neanderthals, including the positioning of the root of the zygomatic process, infraorbital and nasal plates, premaxilla, buccal and labial alveolus, maxillary sinus, nasal cavity, and verticality of anterior tooth implantation. The morphology of the Guercy 3 maxilla more closely approximates that of Sima de los Huesos Preneanderthals, while the dentition more closely approximates the Early-Late Neanderthal condition. Maxillary remains of children and juveniles between MIS 14-MIS 5e are rare, and the available sample is fragmentary and distorted. Although fragmentary, the Guercy 3 maxilla is undistorted and provides new insights into the evolution of the midface in Neanderthals.
Topics: Humans; Child; Animals; Neanderthals; Maxilla; Skull; France; Fossils; Hominidae
PubMed: 37010952
DOI: 10.1002/ar.25218 -
Journal of Dental Research Sep 2023Regeneration of alveolar bone is an essential step in restoring healthy function following tooth extraction. Growth of new bone in the healing extraction socket can be...
Regeneration of alveolar bone is an essential step in restoring healthy function following tooth extraction. Growth of new bone in the healing extraction socket can be variable and often unpredictable when systemic comorbidities are present, leading to the need for additional therapeutic targets to accelerate the regenerative process. One such target is the TAM family (Tyro3, Axl, Mertk) of receptor tyrosine kinases. These proteins have been shown to help resolve inflammation and maintain bone homeostasis and thus may have therapeutic benefits in bone regeneration following extraction. Treatment of mice with a pan-TAM inhibitor (RXDX-106) led to accelerated alveolar bone fill following first molar extraction in a mouse model without changing immune infiltrate. Treatment of human alveolar bone mesenchymal stem cells with RXDX-106 upregulated Wnt signaling and primed the cells for osteogenic differentiation. Differentiation of human alveolar bone mesenchymal stem cells with osteogenic media and TAM-targeted inhibitor RXDX-106 (pan-TAM), ASP-2215 (Axl specific), or MRX-2843 (Mertk specific) showed enhanced mineralization with pan-TAM or Mertk-specific inhibitors and no change with Axl-specific inhibitor. First molar extractions in Mertk mice had increased alveolar bone regeneration in the extraction socket relative to wild type controls 7 d postextraction. Flow cytometry of 7-d extraction sockets showed no difference in immune cell numbers between Mertk and wild type mice. RNAseq of day 7 extraction sockets showed increased innate immune-related pathways and genes associated with bone differentiation in Mertk mice. Together, these results indicate that TAM receptor signaling, specifically through Mertk, can be targeted to enhance bone regeneration after injury.
Topics: Humans; Mice; Animals; c-Mer Tyrosine Kinase; Axl Receptor Tyrosine Kinase; Proto-Oncogene Proteins; Osteogenesis; Tooth Extraction; Tooth Socket
PubMed: 37350025
DOI: 10.1177/00220345231177996 -
Journal of Periodontal Research Aug 2023Teeth are subject to a variety of mechanical forces and vectors. The periodontal ligament (PDL), fibrous tissue that connects the cementum of the tooth to the bony... (Review)
Review
Teeth are subject to a variety of mechanical forces and vectors. The periodontal ligament (PDL), fibrous tissue that connects the cementum of the tooth to the bony socket, plays a decisive role in transmitting force to alveolar bone via Sharpey fibers, transforming and converting these forces into biological signals. This interaction effects significant osteoblastic and osteoclastic responses via autocrine proliferative and paracrine responses. Recent discoveries of receptors for temperature and touch by the Nobel laureates David Julius and Ardem Patapoutian, respectively have a profound impact on orthodontics. Transient receptor vanilloid channel 1 (TRPV1), initially described as a receptor for temperature, has been proposed to participate in the sensing of force. TRPV4, another ion channel receptor, perceives tensile forces as well as thermal and chemical stimuli. Piezo1 and 2, the classic receptors for touch, in addition to the aforementioned receptors, have similarly been described on PDL-derived cells. In this text, we review the role of the temperature-sensitive ion channels and mechanosensitive ion channels on their biological function and influence in orthodontic treatment.
Topics: Periodontal Ligament; Temperature; Ion Channels; Dental Cementum; Mechanotransduction, Cellular
PubMed: 37291724
DOI: 10.1111/jre.13137