Stem cells in clinical dentistry.

Background: Stem cells are present in most of the tissues in the craniofacial complex and play a major role in tissue homeostasis and repair. These cells are characterized by their capacity to differentiate into multiple cell types and to self-renew to maintain a stem cell pool throughout the life of the tissue.

Types Of Studies Reviewed: The authors discuss original data from experiments and comparative analyses and review articles describing the identification and characterization of stem cells of the oral cavity.

PDGF-BB signaling PDGFR-β regulates the maturation of blood vessels generated upon vasculogenic differentiation of dental pulp stem cells.

A functional vascular network requires that blood vessels are invested by mural cells. We have shown that dental pulp stem cells (DPSC) can undergo vasculogenic differentiation, and that the resulting vessels anastomize with the host vasculature and become functional (blood carrying) vessels. However, the mechanisms underlying the maturation of DPSC-derived blood vessels remains unclear.

Virtual clinic: Applying technology to expand dental school walls.

Dental education traditionally requires the use of dedicated fixed preclinic facilities to provide clinically relevant experiences to support the development of dexterity, critical thinking, and self-assessment skills that are essential for excellent patient care. As a result of the social distancing guidelines instituted at the height of the COVID pandemic, dental education was severely affected when education pivoted to remote instruction and had significant restrictions on in-person training. This study evaluated a novel application of modern technology to allow students to perform clinically relevant hands-on exercises away from dental school and, most importantly, receive feedback on their performance as an aid in their development.

p53 Inhibits Bmi-1-driven Self-Renewal and Defines Salivary Gland Cancer Stemness.

Purpose: Mucoepidermoid carcinoma (MEC) is a poorly understood salivary gland malignancy with limited therapeutic options. Cancer stem cells (CSC) are considered drivers of cancer progression by mediating tumor recurrence and metastasis. We have shown that clinically relevant small molecule inhibitors of MDM2-p53 interaction activate p53 signaling and reduce the fraction of CSC in MEC.

Pulpbow: A Method to Study the Vasculogenic Potential of Mesenchymal Stem Cells from the Dental Pulp.

Understanding how Mesenchymal Stem Cells (MSCs) form blood vessels is critical for creating mechanism-based approaches for the therapeutic use of these cells. In addition, understanding the determinants and factors involved in lineage hierarchy is fundamental to creating accurate and reliable techniques for the study of stem cells in tissue engineering and repair. Dental Pulp Stem Cells (DPSC) from permanent teeth and Stem cells from Human Exfoliated Deciduous teeth (SHED) are particularly interesting sources for tissue engineering as they are easily accessible and expandable.

Preclinical assessment of Class IV proximal contacts following different teaching strategies.

Introduction: Class IV composite restorations are one of the biggest challenges in dentistry. Furthermore, replacing adequate proximal contours on Class IV restorations is crucial for the function and aesthetics. The objective of this study is to assess four different teaching strategies used to improve first-year dental students' Class IV restoration proximal contact performance over a period of 4 years.

Survival of salivary gland cancer stem cells requires mTOR signaling.

Advanced salivary gland mucoepidermoid carcinoma (MEC) is a relentless cancer that exhibits resistance to conventional chemotherapy. As such, treatment for patients with advanced MEC is tipically radical surgery and radiotherapy. Facial disfigurement and poor quality of life are frequent treatment challenges, and many patients succumb to loco-regional recurrence and/or metastasis.

Phenotype changes of oral epithelial stem cells after in vitro culture.

The aim of our study was to isolate populations of keratinocyte stem cells based on the expression of cell surface markers and to investigate whether the culture could affect their phenotype. keratinocytes from human oral mucosa were sorted based on the expression of the epithelial stem cell markers p75NTR and CD71. We also examined the co-expression of other epithelial stem markers such as integrins β1 and α6 and their stem cell-like proprieties in in vitro assays.

Characterization of progenitor/stem cell population from human dental socket and their multidifferentiation potential.

Dental stem cells have many applications in medicine, dentistry and stem cell biology in general due to their easy accessibility and low morbidity. A common surgical manoeuvre after a tooth extraction is the dental socket curettage which is necessary to clean the alveolus and favour alveolar bone healing. This procedure can cause very low morbidity compared to bone marrow collection procedures and the collected material is normally discarded.

Apical Papilla Cells Are Capable of Forming a Pulplike Tissue with Odontoblastlike Cells without the Use of Exogenous Growth Factors.

Introduction: Dental pulp is a complex tissue with highly differentiated cells, which makes its reconstruction a challenging task. The apical papilla is an undifferentiated tissue considered as the remnant of the dental papilla that forms the dentin-pulp complex. Aiming to analyze morphologic features of the tissue formed in an in vivo pulp model, we used human apical papilla as a cell source without the use of exogenous growth factors.

Can stem cells enhance bone formation in the human edentulous alveolar ridge? A systematic review and meta-analysis.

Several non-biological materials are currently being used to increase the alveolar bone volume to support dental implants. Recently, stem cell therapy has emerged as a promising biological substitute or adjuvant to enhance bone healing. In order to determine if stem cell therapy has enough clinical evidence to bone ridge augmentation in humans, a systematic review and meta-analysis were conducted.

Expression of CD90 and P75NTR stem cell markers in ameloblastomas: a possible role in their biological behavior.

Multicystic and unicystic ameloblastomas are benign odontogenic tumors that present distinct biological behavior. The investigation of stem cells has become an important branch of tumor biology, with several studies addressing the possible role of these cells in tumor growth, angiogenesis, progression, infiltration and invasiveness. This study evaluated the immunohistochemical expression of CD90(Thy-1) and P75NTR stem cell markers in multicystic and unicystic ameloblastomas.

Synchrotron radiation X-ray micro-fluorescence: Protocol to study mesenchymal stem cells.

The micro-X-ray fluorescence by synchrotron radiation (μ-XRF) is a method to determine the composition of tissues without destroying the samples. However, this technique has never been used for the analysis of mesenchymal stem cells (MSC). This study compared different protocols for fixing, storing, preserving, and establishing the correct numbers of dental derived MSC submitted to μ-XRF analysis.

ALDH/CD44 identifies uniquely tumorigenic cancer stem cells in salivary gland mucoepidermoid carcinomas.

A small sub-population of cells characterized by increased tumorigenic potential, ability to self-renew and to differentiate into cells that make up the tumor bulk, has been characterized in some (but not all) tumor types. These unique cells, namedcancer stem cells, are considered drivers of tumor progression in these tumors. The purpose of this work is to understand if cancer stem cells play a functional role in the tumorigenesis of salivary gland mucoepidermoid carcinomas.

Recurrent multicentric peripheral ossifying fibroma-like lesion in a child: a case report.

Background: Gingival hyperplasias are peculiar conditions that may produce extreme growth that impairs masticatory function and causes psychological and aesthetic disturbances. They can vary from mild interdental papillae localized growth to marked swelling affecting both jaws.

Case Presentation: The aim of this case report is to present a rare case of generalized gingival growth diagnosed in a 4 year-old Caucasian child and followed for 9 years.

Can SHED or DPSCs be used to repair/regenerate non-dental tissues? A systematic review of in vivo studies.

Dental pulp has been identified as a novel and promising stem cell source. The following systematic review presents and summarises in vivo studies that have used stem cells from the dental pulp of permanent and deciduous teeth to repair or regenerate non-dental tissues. An electronic customised search was performed using 4 different databases (Entrez PubMed, Cab Abstracts, Scopus and Web of Science).

Aqueous-ozone irrigation of bone monocortical wounds in hyperglycemic rats.

Purpose: To analyze the effects of aqueous ozone irrigation over bone healing in hyperglycemia-induced rats.

Methods: Forty-eight male Wistar rats were allocated into Group H (hyperglycemic) or Group N (control). Monocortical bone wound were performed on femurs' anterolateral face.

Oral myiasis in two children.

The term myiasis refers to growth of parasitic diptera in the living or dead tissue of vertebrate animal. Most cases of myiasis in humans are mild and rarely present in the mouth. We describe 2 children with severe oral myiasis that evolved to oral and maxillofacial mutilations.

Ring1a/b polycomb proteins regulate the mesenchymal stem cell niche in continuously growing incisors.

Rodent incisors are capable of growing continuously and the renewal of dental epithelium giving rise to enamel-forming ameloblasts and dental mesenchyme giving rise to dentin-forming odontoblasts and pulp cells is achieved by stem cells residing at their proximal ends. Although the dental epithelial stem cell niche (cervical loop) is well characterized, little is known about the dental mesenchymal stem cell niche. Ring1a/b are the core Polycomb repressive complex1 (PRC1) components that have recently also been found in a protein complex with BcoR (Bcl-6 interacting corepressor) and Fbxl10.

Vimentin expression and the influence of Matrigel in cell lines of head and neck squamous cell carcinoma.

Vimentin is a cytoeskeletal intermediate filament protein commonly observed in mesenchymal cells; however, it can also be found in malignant epithelial cells. It is demonstrated in several carcinomas, such as those of the cervix, breast and bladder, in which it is widely used as a marker of the epithelial to mesenchymal transition that takes place during embryogenesis and metastasis. Vimentin is associated with tumors that show a high degree of invasiveness, being detected in invasion front cells.

Dual origin of mesenchymal stem cells contributing to organ growth and repair.

In many adult tissues, mesenchymal stem cells (MSCs) are closely associated with perivascular niches and coexpress many markers in common with pericytes. The ability of pericytes to act as MSCs, however, remains controversial. By using genetic lineage tracing, we show that some pericytes differentiate into specialized tooth mesenchyme-derived cells--odontoblasts--during tooth growth and in response to damage in vivo.

Perivascular cells as mesenchymal stem cells.

Importance Of The Field: Mesenchymal stem cells are multipotent adult stem cell populations that have broad differentiation plasticity and immunosuppressive potential that render them of great importance in cell-based therapies. They are identified by in vitro characteristics based on their differentiation potential for clinical approaches while their biological properties and in vivo identities are often less understood.

Areas Covered In This Review: Recent research carried out in the last decade on mesenchymal stem cell biology suggests that mesenchymal stem cells from various tissues reside in a perivascular location and these can be identified as pericytes that function as mural cells in microvessels.

Importance of cone beam computed tomography for diagnosis of calcifying cystic odontogenic tumour associated to odontoma. Report of a case.

The calcifying cystic odontogenic tumour (CCOT) is a rare benign cystic neoplasm not infrequently associated with odontoma. This report documents a case of CCOT associated with compound odontoma arising in the anterior maxilla in a 25-year-old woman. Conventional radiographs showed a large calcified mass with poorly visualized radiolucent margins.

Chondrosarcoma of the mandible: case report and literature review.

Chondrosarcoma is a malignant cartilaginous tumor that rarely occurs in the maxillofacial bones. A 44-year-old woman complained about swelling and mild pain during mastication in the right parasymphysis region. Clinical and radiographic examinations revealed characteristics of osteosarcoma.