The aim of this study is to observe the time of mixing influence on the properties of commercially available PMMA bone cement, widely used in cranioplasty. The studied bone cement is provided in the form of a solid powder (the copolymer) and a liquid monomer. The increase of the mixing phase duration and the use of two mixing methods (manual and mechanical) effect on surface and mechanical characteristics were studied. The samples were prepared as if in the operation room. Surface characteristics were studied by means of contact angle measurements, morphology by scanning electron microscopy (SEM) and mechanical characteristics determined by flexural tests in a three point bending configuration. The conclusion of this study is that by using a mechanical mixing method and increasing mixing time higher flexural strength can be achieved by reducing pore content within bone cement.
Mast cell (MC) active mediators promote inflammation through changes induced in the connective tissue components of human gingiva. The aim of this study was to evaluate the distribution, mast cell density and their relationship with the degree of inflammatory infiltrate in gingiva from patients with periodontal disease. Thirty-nine cases with periodontal disease and 12 cases without significant changes to the gingival mucosa were investigated. MCs were identified on paraffin-embedded specimens by immunohistochemistry using anti-mast cell tryptase. The inflammatory infiltrate was scored from 0 to 3, and the MCs were counted using the hotspot method. Intraepithelial MCs were scored from 0 to 2. We found a significant increase of mast cell density in cases with mild and moderate inflammatory changes, and a slight decrease in patients with severe periodontal disease. We noticed a higher degranulation rate in patients with periodontal disease compared to those with healthy mucosa. Intraepithelial MCs were found in cases with periodontal disease only and were correlated with the severity of the inflammatory lesion. MCs are important cellular components of the early stages of periodontal disease. Contrary to other studies, we found that MC density and activation increases with moderate inflammation but decreases in severe inflammatory lesions. Our data suggest that MCs are key players in the progression of inflammatory lesions of the gingiva. In advanced-stage periodontal disease, intraepithelial MCs apparently play an important role, although their biological significance remains to be fully understood.
Implants and biomaterials used in hard and soft oral tissue augmentation are very complex, but predictable to use nowadays, as the technological advances haven�t skipped this field of medicine. Cases that were impossible to treat with implant retained fixed prosthesis some years ago, have become the daily practice of oral surgeons and dentists around the world. The new user-friendly products, together with simplified protocols, increased the practitioners� predictability and success rate, thus the biomaterial industry took a huge leap forward. As the biomaterial industry keeps developing continuously, making better and safer products, the surgical and prosthetic protocols evolve and change as well. On this matter, the implant placement has become safer, using digital surgical guides. Guided implant placement doesn�t just allow the practitioner place the implant in the patient�s bone, but, moreover, it helps him place it in the correct, 3D, prosthetic position. And, thus, guiding the future bone augmentation and regeneration as well, accordingly. So, the implant placement has shifted from bone-orientated to prosthetic-orientated, offering at the same time a better primary stability for the implants, due to the prior planning. The present clinical study aims to analyze the outcome of the digital guided protocol. Unlike the free-handed surgery, the digital guided surgery allows dentists and oral surgeons to place implants according to the future prosthetic position of the crowns, even in conditions of alveolar ridges with bone resorption. Moreover, it makes possible the �one day implant� concept, the dental technician being able to create the provisional crown/s in advance, knowing precisely the future position of the implant placement. So, at the time of the surgery, the provisional crown is also put in place, guiding the soft and hard tissue healing and also giving the patient a greater satisfaction.
The aim of the study was to evaluate and to compare the interface and marginal leakage of dental composite resins using confocal laser scanning biological microscopy (CM). Ten class II cavities were prepared on the proximal surfaces of 10 extracted teeth, previously kept in 10% formalin to preserve the bonding properties of the tooth structures. Cavities were restored with dental composite resin using the �open sandwich� technique and then assessed using CM. Open marginal adaptations at the interfaces inside the composite resins were identified. The results obtained with CM helped to eliminate and reduce the background information collected from a distance from the focal plane and allowed for the acquisition of serial optical sections from thick tooth specimens. In vitro assessments were thus made using CM on the teeth structure, regarding the occurrence of potential micro-leakages at the restoration interface.
Background and Objectives: Halitosis is a condition characterized by unpleasant breath smell that is starting to receive serious scientific attention, considering it reflects on people’s social and personal life. While most studies focus on the prevalence of halitosis, its medical etiology, and the psychological impact on adults, there is a lack of evidence regarding the social impact of halitosis on the younger population. Therefore, this systematic review aimed to observe the social and emotional impact that halitosis has on adolescents and young adults. Materials and Methods: The review followed the PRISMA protocol, and four electronic databases (Scopus, Scholar, Web of Science, and ProQuest) were searched. From a total of 593 studies retrieved, only 6 were included in the study after assessing the eligibility criteria. Results: The main results showed that the levels of self-reported halitosis ranged from 23.1% to 77.5%, with an average of 44.7%, indicating a significant heterogeneity among the studies reporting this issue. Adolescents and young adults who experienced bad breath were feeling more anxious and depressed according to the non-standardized questionnaires and the standardized questionnaires (OHIP-14 and SCL-9-R). The respondents were isolated from social interactions and consequently had lower self-esteem and impaired quality of life. Conclusions: The conclusions drawn indicate the need for action on a medical level, as well as on a psychological level, in order to improve people’s oral health and help them navigate through the difficulties of maintaining social interactions as they live with halitosis.
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