Nano-hydroxyapatite (nano-HA) is a material with multiple uses due to its biocompatibility and its resemblance to the nonorganic bone structure. It is used in various dental domains such as implantology, surgery, periodontology, esthetics and prevention. The aim of this study is to provide a wide understanding of nano-HA and to promote treatments based on nanomaterials in dentistry. A search in two data bases, Scopus, and PubMED, was conducted over a 5 years period. We chose a 5 years period because this revealed the most recent published studies with the key words ‘nano-HA’ and ‘dentistry’. A number of 32 studies were included in this systematic review. In implantology the main use of nano-HA was as a coating material for titanium implants and its effect was assessed in the matter of osteointegration and inflammatory response as well as antibacterial activity. In tissue engineering the use of nano-HA was directed to surgery and periodontology and this material was assessed mainly as a grafting material. In esthetics and prevention its use was mainly focused on dentinal hypersensitivity treatment, remineralizing potential and as bleaching co-agent. Nano-HA is a relatively novel material with outstanding physical, chemical, mechanical and biological properties that makes it suitable for multiple interventions. It outperformed most of the classic materials used in implantology and surgery but it should be further investigated for bone engineering and caries prevention therapy.
We aimed to demonstrate that DF stem cells from impacted molars and canines can be used to improve bone regeneration on titanium implants surfaces. This study highlights the presence of stem cells in DF, their potential to adhere and differentiate into osteoblasts on different types of titanium surfaces. Isolated cells from the harvested DF tissue from impacted canine/molars, expressed stem cells markers. Differentiation into bone cells was induced in presence or absence of BMP-2 and TGFβ1. The presence of growth factors until 28 days in medium maintained the cells in an earlier stage of differentiation with a lower level of specific bone proteins and a higher expression of alkaline phosphatase (ALP). Influence of titanium implants with different bioactive coatings, hydroxyapatite (TiHA) and with silicatitanate (TiSiO2), and porous Ti6Al7Nb implants as control (TiCtrl), was studied in terms of cell adhesion and viability. Ti HA implants proved to be more favorable for adhesion and proliferation of DF stem cells in first days of cultivation. The influence of titanium coatings and osteogenic differentiation mediums with or without growth factors were evaluated. Additional BMP-2 in the medium did not allow DF stem cells to develop a more mature phenotype, leaving them in a pre-osteogenic stage. The best sustained mineralization process evaluated by immuno-cytochemical staining, scanning electron microscopy and Ca2+ quantification was observed for TiHA implants with a higher expression of ALP, collagen and Ca2+ deposition. Long term culturing (70 days) on titanium surfaces of DF stem cells in standard medium without soluble osteogenic inducers, indicated that HA coating is more favorable, with the acquisition of a more mature osteoblastic phenotype as shown by immunocytochemical staining. These findings demonstrated that even in absence of exogenous osteogenic factors, TiHA implants and in a lesser extent TiCtrl and TiSiO2 implants can induce and sustain osteogenic differentiation of DF stem cells, by their chemical and topographical properties. Our research demonstrated that DF stem cells have a spontaneous tendency for osteogenic differentiation and can be used for improving bone regeneration on titanium implants surfaces.
Assessing bone density in prospective dental implant sites is crucial both for choosing the implant type and for planning a drilling procedure that will ensure the implant’s primary stability and osseointegration. This study aimed to investigate possible differences between the bone densities of various edentulous sites in the maxilla and mandible. The study was conducted on a group of forty partly edentulous patients who underwent radiological examination by scanning the areas of interest using cone beam computed tomography (CBCT). Hounsfield units (HU) were analyzed using dedicated software. Higher HU were observed at the site of mandibular central incisors compared to the site of maxillary central incisors. The HU values in the mandibular first molars region were higher than those of the maxillary first molars. Buccal vs. lingual or palatal cortical HU values did not differ significantly. Within the limitations of this study, it can be stated that an objective assessment of site-specific bone density before the installation of dental implants may provide valuable clinical information for the selection of implant size and the planning of a patient-specific drilling protocol.
Oral cancer is a common human malignancy that still maintains an elevated mortality rate despite scientific progress. Tumorigenesis is driven by altered gene expression patterns of proto-oncogenes and tumor-suppressor genes. MicroRNAs, a class of short non-coding RNAs involved in gene regulation, seem to play important roles in oral cancer development, progression, and tumor microenvironment modulation. As properties of microRNAs render them stable in diverse liquid biopsies, together with their differential expression signature in cancer cells, these features place microRNAs at the top of promising biomarkers for diagnostic and prognostic values. In this review, we highlight eight expression levels and functions of the most relevant microRNAs involved in oral cancer development, progression, and microenvironment sustainability. Furthermore, we emphasize the potential of using these small RNA species as non-invasive biomarkers for the early detection of oral cancerous lesions. Conclusively, we highlight the perspectives and limitations of microRNAs as novel diagnostic tools, as well as therapeutic models.
Introduction : To establish the skeletal pattern in subjects with malocclusions and temporomandibular disorders (TMD); to assess the relationship between craniofacial skeletal structures and TMD in subjects with malocclusions. Material and methods: Sixty-four subjects with malocclusions,...