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Monographs in Oral Science 2023Pathology is the science of how a tissue changes during the process of the disease. The pathology is of important knowledge for understanding subsequent treatment... (Review)
Review
Pathology is the science of how a tissue changes during the process of the disease. The pathology is of important knowledge for understanding subsequent treatment concepts of a disease. In the cariology field, pathological features of caries are often presented using tooth sections, whereby the sequence and spread can be monitored. It is optimal to describe such changes using thin undecalcified tooth sections as an overview can be given of both enamel demineralization and pulp-dentine reactions. Also, an optimal understanding is achieved if the clinical status of carious lesion activity is known. Different studies using human teeth have shown the principle changes in progressive stages of carious lesions; the growth of the enamel lesion reflects the growth condition of the cariogenic biofilm. Surprisingly, the pulp (the odontoblast) is aware of the cariogenic stimuli even before mineral alteration has taken place within the dentine. The microorganisms mainly invade the dentine during enamel cavitation. In this chapter, the current improvement of knowledge on advanced carious lesions has been assessed in detail both histologically and radiographically. From a radiographic point of view, well-defined deep and extremely deep carious lesions and their difference are presented. Recent advances in artificial intelligence (AI) in medicine have raised the possibility of increasing the accuracy and speed of histopathological examination techniques. However, the literature involving AI-based histopathological features of hard and soft dentinal tissue pathologic changes is still scarce.
Topics: Humans; Dentin; Artificial Intelligence; Dental Caries Susceptibility; Dental Caries; Dental Pulp
PubMed: 37364550
DOI: 10.1159/000530557 -
Journal of Endodontics Nov 2023During pulpitis, as bacteria penetrate deeper into the dentin and pulp tissue, a pulpal innate immune response is initiated. However, the kinetics of the immune...
INTRODUCTION
During pulpitis, as bacteria penetrate deeper into the dentin and pulp tissue, a pulpal innate immune response is initiated. However, the kinetics of the immune response, how this relates to bacterial infiltration during pulpitis and an understanding of the types of immune cells in the pulp is limited.
METHODS
Dental pulp exposure in the molars of mice was used as an animal model of pulpitis. To investigate the kinetics of immune response, pulp tissue was collected from permanent molars at different time points after injury (baseline, day 1, and day 7). Flow cytometry analysis of CD45+ leukocytes, including macrophages, neutrophils monocytes, and T cells, was performed. 16S in situ hybridization captured bacterial invasion of the pulp, and immunohistochemistry for F4/80 investigated spatial and morphological changes of macrophages during pulpitis. Data were analyzed using two-way ANOVA with Tukey's multiple comparisons.
RESULTS
Bacteria mostly remained close to the injury site, with some expansion towards noninjured pulp horns. We found that F4/80 macrophages were the primary immune cell population in the healthy pulp. Upon injury, CD11b Ly6G neutrophils and CD11b Ly6GLy6C monocytes constituted 70-90% of all immune populations up to 7 days after injury. Even though there was a slight increase in T cells at day 7, myeloid cells remained the main drivers of the immune response during the seven-day time period.
CONCLUSIONS
As bacteria proliferate within the pulp chamber, innate immune cells, including macrophages, neutrophils, and monocytes, predominate as the major immune populations, with some signs of transitioning to an adaptive immune response.
Topics: Animals; Immunity, Innate; Disease Models, Animal; Mice; Pulpitis; Dental Pulp; Macrophages; Neutrophils; Monocytes; Flow Cytometry
PubMed: 37678750
DOI: 10.1016/j.joen.2023.08.019 -
International Journal of Oral Science Aug 2023Carious lesions are bacteria-caused destructions of the mineralised dental tissues, marked by the simultaneous activation of immune responses and regenerative events...
Carious lesions are bacteria-caused destructions of the mineralised dental tissues, marked by the simultaneous activation of immune responses and regenerative events within the soft dental pulp tissue. While major molecular players in tooth decay have been uncovered during the past years, a detailed map of the molecular and cellular landscape of the diseased pulp is still missing. In this study we used single-cell RNA sequencing analysis, supplemented with immunostaining, to generate a comprehensive single-cell atlas of the pulp of carious human teeth. Our data demonstrated modifications in the various cell clusters within the pulp of carious teeth, such as immune cells, mesenchymal stem cells (MSC) and fibroblasts, when compared to the pulp of healthy human teeth. Active immune response in the carious pulp tissue is accompanied by specific changes in the fibroblast and MSC clusters. These changes include the upregulation of genes encoding extracellular matrix (ECM) components, including COL1A1 and Fibronectin (FN1), and the enrichment of the fibroblast cluster with myofibroblasts. The incremental changes in the ECM composition of carious pulp tissues were further confirmed by immunostaining analyses. Assessment of the Fibronectin fibres under mechanical strain conditions showed a significant tension reduction in carious pulp tissues, compared to the healthy ones. The present data demonstrate molecular, cellular and biomechanical alterations in the pulp of human carious teeth, indicative of extensive ECM remodelling, reminiscent of fibrosis observed in other organs. This comprehensive atlas of carious human teeth can facilitate future studies of dental pathologies and enable comparative analyses across diseased organs.
Topics: Humans; Dental Pulp; Fibronectins; Extracellular Matrix; Dental Caries; Sequence Analysis, RNA
PubMed: 37532703
DOI: 10.1038/s41368-023-00238-z -
International Endodontic Journal Dec 2023To determine the prevalence of symptoms, clinical signs and radiographic presentation of external cervical resorption (ECR). (Observational Study)
Observational Study
AIM
To determine the prevalence of symptoms, clinical signs and radiographic presentation of external cervical resorption (ECR).
METHODOLOGY
This study involved 215 ECR lesions in 194 patients referred to the Endodontic postgraduate Unit at King's College London or Specialist Endodontic practice (London, UK). The clinical and radiographic findings (periapical [PA] and cone beam computed tomography [CBCT]) were readily accessible for evaluation. A checklist was used for data collection. Inferential analysis was carried out to determine if there was any potential association between type and location of tooth in the jaw as well as sex, age of the patient and ECR presentation and radiographic feature.
RESULTS
Eighty-eight patients (94 teeth) were female and 106 patients were male (121 teeth), the mean age (±SD) was 41.5 (±17.7) years. Fifteen patients (7.7%) had more than one ECR lesion. The most affected teeth were maxillary central incisors (21.4% [46 teeth]) and mandibular first molars (10.2% [22 teeth]). ECR was most commonly detected as an incidental radiographic finding in 58.1% [125 teeth] of the cases. ECR presented with symptoms of pulpal/periapical disease in 23.3% [n = 50] and clinical signs (e.g. pink spot, cavitation) in 16.7% [36 teeth] of the cases. Clinical signs such as cavitation (14%), pink spot (5.1%) and discolouration (2.8%) were uncommon, but their incidence increased up to 24.7% when combined with other clinical findings. ECR was detected in the resorptive and reparative phases in 70.2% and 29.8% of the cases respectively.
CONCLUSION
ECR appears to be quiescent in nature, the majority being asymptomatic and diagnosed incidentally from PA or CBCT. When assessed with the Patel classification, most lesions were minimal to moderate in relation to their height (1 or 2) and circumferential spread (A or B). However, the majority of ECRs were in (close) proximity to the pulp. Symptoms and clinical signs were associated with (probable) pulp involvement rather than the height and circumferential spread of the lesion. Clinical signs were more frequently associated when ECR affected multiple surfaces.
Topics: Humans; Male; Female; Young Adult; Adult; Middle Aged; Tooth Cervix; Cone-Beam Computed Tomography; Dental Pulp; Incisor; Molar; Dental Pulp Diseases; Root Resorption
PubMed: 37801348
DOI: 10.1111/iej.13968 -
Stem Cell Reviews and Reports Aug 2021Deep caries, trauma, and severe periodontitis result in pulpitis, pulp necrosis, and eventually pulp loss. However, no clinical therapy can regenerate lost pulp. A novel... (Review)
Review
Deep caries, trauma, and severe periodontitis result in pulpitis, pulp necrosis, and eventually pulp loss. However, no clinical therapy can regenerate lost pulp. A novel pulp regeneration strategy for clinical application is urgently needed. Signaling transduction plays an essential role in regulating the regenerative potentials of dental stem cells. Cytokines or growth factors, such as stromal cell-derived factor (SDF), fibroblast growth factor (FGF), bone morphogenetic protein (BMP), vascular endothelial growth factor (VEGF), WNT, can promote the migration, proliferation, odontogenic differentiation, pro-angiogenesis, and pro-neurogenesis potentials of dental stem cells respectively. Using the methods of signaling modulation including growth factors delivery, genetic modification, and physical stimulation has been applied in multiple preclinical studies of pulp regeneration based on cell transplantation or cell homing. Transplanting dental stem cells and growth factors encapsulated into scaffold regenerated vascularized pulp-like tissue in the root canal. Also, injecting a flowable scaffold only with chemokines recruited endogenous stem/progenitor cells for pulp regeneration. Notably, dental pulp regeneration has gradually developed into the clinical phase. These findings enlightened us on a novel strategy for structural and functional pulp regeneration through elaborate modulation of signaling transduction spatially and temporally via clinically applicable growth factors delivery. But challenges, such as the adverse effects of unphysiological signaling activation, the controlled drug release system, and the safety of gene modulation, are necessary to be tested in future works for promoting the clinical translation of pulp regeneration.
Topics: Dental Pulp; Humans; Regeneration; Signal Transduction; Stem Cells
PubMed: 33459973
DOI: 10.1007/s12015-020-10117-3 -
Colloids and Surfaces. B, Biointerfaces Sep 2023Exosomes are produced by all the cells and exist in all body fluids. They have been regarded as potentially promising to diagnostic biomarkers and therapeutic bioactive... (Review)
Review
Exosomes are produced by all the cells and exist in all body fluids. They have been regarded as potentially promising to diagnostic biomarkers and therapeutic bioactive mediators since they transport DNA, RNA and protein information from cell to cell. Herein, we summarized the recent research about exosomes from gingival crevicular fluid, saliva and serum used as diagnostic markers in periodontitis and dental caries. Moreover, we highlighted the mechanisms of exosomes in dental pulp regeneration and periodontal regeneration, as well as the technological innovation of exosome delivery methods in oral disease. In the end, this review discussed the advantages and future challenges of exosomes in real clinical applications.
Topics: Humans; Exosomes; Dental Caries; Dental Pulp; Regeneration; Biomarkers
PubMed: 37451223
DOI: 10.1016/j.colsurfb.2023.113429 -
Pulmonary Pharmacology & Therapeutics Dec 2017Mechanisms which alter sensory neural activity, in particular those rendering nerves hyper-responsive have been implicated in the pathophysiology of common clinical... (Review)
Review
Mechanisms which alter sensory neural activity, in particular those rendering nerves hyper-responsive have been implicated in the pathophysiology of common clinical syndromes including chronic cough, itch and pain. However, experimental study of human sensory neurons is challenging because the cell bodies of peripheral neurons are housed in neuronal ganglia which are not accessible using peripheral biopsy techniques. While important advances have been made from studies conducted in animal models, there are interspecies differences. There is a need for development of a new generation of in vitro neuronal models based on human biology. In this article the propensity for human dental pulp stem cells to differentiate towards a neuronal phenotype and the potential of such a model to study altered sensory neural function will be discussed.
Topics: Animals; Cell Differentiation; Chronic Disease; Cough; Dental Pulp; Humans; In Vitro Techniques; Models, Biological; Sensory Receptor Cells; Species Specificity; Stem Cells
PubMed: 28782711
DOI: 10.1016/j.pupt.2017.08.001 -
Odontology May 2016The presence of viruses in endodontic disease has been studied in the last decade. Their presence is associated with periapical radiolucency and with clinical findings,... (Review)
Review
The presence of viruses in endodontic disease has been studied in the last decade. Their presence is associated with periapical radiolucency and with clinical findings, such as pain. The aim of this review is to analyze the scientific evidence currently published about viruses in pulp and periapical inflammation, and its possible clinical implications. A literature review was carried out using the Medline/Pubmed database. The search was performed, in English and Spanish, using the following keyword combinations: virus AND endodontic; virus AND periapical; virus AND pulpitis; herpesvirus AND periapical; papillomavirus AND periapical. We subsequently selected the most relevant studies, which complied with the search criterion. A total of 21 articles were included, of which 18 detected the present of viruses in the samples. In 3 of the studies, viral presence was not found in the samples studied. The Epstein-Barr virus was found in about 41 % of cases compared to controls, in which it was present in about 2 %. The main association between viruses and endodontic pathosis is between Cytomegalovirus and Epstein-Barr virus; these are found in 114 of the 406 samples of different endodontic pathosis. Some evidence supports that the Epstein-Barr virus is present in a significant number of endodontic diseases, without exact knowledge of their action in these diseases.
Topics: Cytomegalovirus; Dental Pulp; Herpesvirus 4, Human; Humans; Inflammation; Periapical Periodontitis
PubMed: 25796386
DOI: 10.1007/s10266-015-0200-y -
The Journal of Contemporary Dental... Jul 2015Paleomicrobiology is a special branch of micropaleontology concerned with the study of bacterial fossils. We have used the term 'oral paleomicrobiology', as in this... (Review)
Review
BACKGROUND
Paleomicrobiology is a special branch of micropaleontology concerned with the study of bacterial fossils. We have used the term 'oral paleomicrobiology', as in this review we have focused on the ancient oral microflora. Recently, dental calculus and dental pulp have been identified as rich sources of ancient microbial DNA. Study of this ancient genetic material opens a new door to the ancient world. This review gives an overview of history of ancient DNA research, various techniques of analyzing ancient DNA in dental calculus and dental pulp, and the implications of the oral paleomicrobiology.
MATERIALS AND METHODS
A comprehensive literature search was performed in the following databases-pubmed, medline and google scholar for studies published before 10 April, 2015. The following keywords were used- 'ancient DNA', 'ancient oral flora, 'oral paleomicrobiology' and 'oral microbiome', '16S rRNA sequencing'. To obtain additional data, a manual search was performed using the reference lists of selected articles.
RESULT
As a result of literature search, 27 articles were found in pubmed, 12 in google scholar and one in medline. Eight more articles were selected from the reference list of selected articles.
CONCLUSION
The combination of microbiology and paleontology has brought a revolution in the study of human evolution and microbial communities. The naturally well-preserved samples of microbial DNA from dental pulp and microbial colonies trapped in dental calculus are a potential source of microbial genetic material, which will prove invaluable in resolving mysteries of the past. This may be a beginning of a new era of oral paleomicrobiology, which will contribute in our studies about prevention of disease by establishing symbiosis between human beings and their microbiome.
Topics: DNA, Bacterial; Dental Calculus; Dental Pulp; History, Ancient; Humans; Microbiota; Paleodontology; Paleontology
PubMed: 26329415
DOI: 10.5005/jp-journals-10024-1726 -
Journal of Dental Research Dec 2014Stemming from in vitro and in vivo pre-clinical and human models, tissue-engineering-based strategies continue to demonstrate great potential for the regeneration of the... (Review)
Review
Stemming from in vitro and in vivo pre-clinical and human models, tissue-engineering-based strategies continue to demonstrate great potential for the regeneration of the pulp-dentin complex, particularly in necrotic, immature permanent teeth. Nanofibrous scaffolds, which closely resemble the native extracellular matrix, have been successfully synthesized by various techniques, including but not limited to electrospinning. A common goal in scaffold synthesis has been the notion of promoting cell guidance through the careful design and use of a collection of biochemical and physical cues capable of governing and stimulating specific events at the cellular and tissue levels. The latest advances in processing technologies allow for the fabrication of scaffolds where selected bioactive molecules can be delivered locally, thus increasing the possibilities for clinical success. Though electrospun scaffolds have not yet been tested in vivo in either human or animal pulpless models in immature permanent teeth, recent studies have highlighted their regenerative potential both from an in vitro and in vivo (i.e., subcutaneous model) standpoint. Possible applications for these bioactive scaffolds continue to evolve, with significant prospects related to the regeneration of both dentin and pulp tissue and, more recently, to root canal disinfection. Nonetheless, no single implantable scaffold can consistently guide the coordinated growth and development of the multiple tissue types involved in the functional regeneration of the pulp-dentin complex. The purpose of this review is to provide a comprehensive perspective on the latest discoveries related to the use of scaffolds and/or stem cells in regenerative endodontics. The authors focused this review on bioactive nanofibrous scaffolds, injectable scaffolds and stem cells, and pre-clinical findings using stem-cell-based strategies. These topics are discussed in detail in an attempt to provide future direction and to shed light on their potential translation to clinical settings.
Topics: Animals; Dental Pulp; Dentin; Humans; Prosthesis Design; Regeneration; Root Canal Therapy; Stem Cells; Tissue Engineering; Tissue Scaffolds
PubMed: 25201917
DOI: 10.1177/0022034514549809