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1.
Germs ; 14(1): 28-37, 2024 Mar.
Article in English | MEDLINE | ID: mdl-39169976

ABSTRACT

Introduction: Assessment of the denture plaque can provide a valuable report regarding the oral health of geriatric patients and the oral hygiene habits in this population group. Focusing on the current research gap on this topic in Romania, our research aims to highlight the microbial plaque on the different surfaces and types of removable poly(methyl methacrylate) (PMMA) prostheses to qualitatively evaluate the microbial species, and to assess the combined effect of mechanical and chemical cleaning of dentures on the prosthetic microbiome. Methods: The prosthetic plaque from four denture wearers was identified with a UV activated fluorescent revealer and digitally photographed. Swab samples according to a certain hygiene protocol were cultured on three different growth media such as blood agar (BA), bromothymol blue lactose agar (AABTL) and Sabouraud dextrose agar (SDA). Results: Denture plaque was variably distributed on the surface of the prostheses. Regardless of the denture type (conventional complete denture, tooth or implant supported overdenture, removable partial denture) the microbial plaque was identified at the retentive areas, especially at interdental spaces. The main plaque deposition areas were the vestibular incline of the labial flange of the maxillary denture and the lingual incline of the posterior lingual flange of the mandibular denture. The prosthetic microbiome consisted of pathogenic Gram-positive aerobes (Streptococcus spp. and coagulase-negative Staphylococcus spp.), Gram-positive anaerobes (Actinomyces spp. and Klebsiella spp.) as well as subspecies of fungi of the genus Candida. Conclusions: Despite its poor variety, the denture microbiome in the investigated cases hosts colonies with high pathogenic potential. Some areas of the prostheses are more likely to accumulate dental plaque. Dentists should insist through more regular checks of the patients and their caregivers on ensuring the biocontrol of the dentures, especially in frail geriatric patients exposed to greater risks related to general health.

2.
J Funct Biomater ; 15(8)2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39194648

ABSTRACT

In contemporary dentistry, several 3D printing techniques, including a stereolithography apparatus (SLA), digital light processing (DLP), liquid crystal display (LCD), and PolyJet 3D inkjet printing technology (PolyJet), are employed for model production. Despite their widespread use, there remains a paucity of the literature regarding the trueness and precision of these devices in dental applications. Existing studies comparing the accuracy of dental models manufactured by different printing technologies yield disparate conclusions regarding dental prosthesis manufacturing. This study aimed to test two null hypotheses: first, that the trueness of various new-generation 3D printers is equivalent, and second, that the trueness of printing by these printers is sufficient for achieving high-precision mastercasts in dental prosthodontics manufacturing. The research focuses on evaluating the trueness of five contemporary dental 3D printers: Anycubic Mono X 6Ks (Hongkong Anycubic Technology Co., Hongkong, China), Asiga Max (Asiga, Sydney, Australia), Creo C5 (Planmeca Oy, Helsinki, Finland), Form 3B (Formlabs, Boston, MA, USA), and J5 Dentajet (Stratasys Ltd., Eden Prairie, MN, USA). The methodology employed involved the creation of a digital test object using Blender software, adhering meticulously to the dimensions outlined in ISO standard 20896-1. These dimensions were chosen to be both relevant for this study and representative of clinical scenarios. Subsequently, the test object was printed and precise measurements were conducted utilizing a metrology-type Nikon XTH225 ST Reflection target in conjunction with VGStudio MAX analysis software. The results of our investigation revealed clinically negligible deviations in ball dimensions across all printers, with the maximum observed deviations ranging between 1.17% and 2.03% (notably observed in the Creo C5 printer). Transversal distortion exhibited variance based on the linear accuracy of each printer, with Stratasys21 and Formlabs 3B demonstrating superior accuracy among the evaluated printers. Distortions in the analyzed dimensions (specifically, anterior b-c, posterior a-d, and oblique a-c) were found to be uniform. In conclusion, while the first null hypothesis was rejected, indicating variations in trueness among the 3D printers assessed, our findings affirm the suitability of all five analyzed 3D printers for clinical applications. Consequently, these printers can be utilized for the fabrication of high-precision mastercasts in dental prosthodontics manufacturing.

3.
Diagnostics (Basel) ; 14(13)2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39001343

ABSTRACT

(1) Background: Intraoral scanners undergo rapid advancements in hardware and software, prompting frequent updates by manufacturers. (2) Aim: This study aimed to quantitatively assess the precision of full dental arch digital impressions obtained from four different intraoral scanners: Trios 5-3SHAPE, Copenhagen, Denmark, CEREC Primescan- Dentsply Sirona, New York, NY, USA, Planmeca Emerald S-Planmeca Oy, Helsinki, Finland, and Medit i700-Medit Corp, Seoul, Republic of Korea. (3) Methods: A maxillary virtual dental model (digital master model) was created in accordance with ISO standard 20896-1. Subsequently, a 3D-printed model was obtained from the master model's STL file and scanned 15 times consecutively with each scanner. STL files were aligned with the master model's STL using Medit Link-Medit Design software v.3.1.0. The accuracy was evaluated by measuring deviations in micrometers between each scanner's scans and the master model. (4) Results: The study revealed variations in accuracy ranging from 23 to 32 µm across scans of the same dental arch, irrespective of the scanner used and scanning strategy employed. The anterior regions exhibited higher precision (Mean Absolute Deviation of 112 µm) compared to the posterior regions (Mean Absolute Deviation of 127 µm). Trios 5 demonstrated the smallest deviation (average 112 µm), indicating superior accuracy among the scanners tested. Emerald S and Medit i700 exhibited balanced performance (average 117 µm and 114 µm, respectively), while Primescan consistently displayed high deviation (average 127 µm). (5) Conclusions: Based on clinically accepted thresholds for accuracy in intraoral scanning, which are typically 200 µm for full arch scans, Trios 5 surpasses these benchmarks with its average deviation falling within the 200 µm range. Emerald S and Medit i700 also meet these standards, while Primescan, although showing high overall deviation, approaches the upper limit of clinical acceptability. Considering the limitations of an in vitro investigation, the findings demonstrate that each intraoral scanner under evaluation is capable of reliably and consistently capturing a full arch scan for dentate patients.

4.
J Funct Biomater ; 15(6)2024 May 28.
Article in English | MEDLINE | ID: mdl-38921521

ABSTRACT

Computer-aided design and computer-aided manufacturing (CAD/CAM) techniques are based on either subtractive (milling prefabricated blocks) or additive (3D printing) methods, and both are used for obtaining dentistry materials. Our in vitro study aimed to investigate the behavior of human gingival fibroblasts exposed to methacrylate (MA)-based CAD/CAM milled samples in comparison with that of MA-based 3D-printed samples to better elucidate the mechanisms of cell adaptability and survival. The proliferation of human gingival fibroblasts was measured after 2 and 24 h of incubation in the presence of these samples using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the membrane integrity was assessed through the lactate dehydrogenase release. The level of reactive oxygen species, expression of autophagy-related protein LC3B-I, and detection of GSH and caspase 3/7 were evaluated by fluorescence staining. The MMP-2 levels were measured using a Milliplex MAP kit. The incubation with MA-based 3D-printed samples significantly reduced the viability, by 16% and 28% from control after 2 and 24 h, respectively. There was a 25% and 55% decrease in the GSH level from control after 24 h of incubation with the CAD/CAM milled and 3D-printed samples, respectively. In addition, higher levels of LC3B-I and MMP-2 were obtained after 24 h of incubation with the MA-based 3D samples compared to the CAD/CAM milled ones. Therefore, our results outline that the MA-CAD/CAM milled samples displayed good biocompatibility during 24-h exposure, while MA-3D resins are proper for short-term utilization (less than 24 h).

5.
Healthcare (Basel) ; 12(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38727440

ABSTRACT

Oral health is situated within the framework of the global health agenda, addressing facets pertaining to well-being and quality of life. The research is based on the need to address variables at the community level to improve schoolchildren's oral health and promote healthy behaviors and aims to carry out an in-depth analysis from the perspective of the factors that influence children's oral health. Step 1, designed by the World Health Organization, was utilized. An easy-to-use web interface was created for data collection. The statistical analysis consisted of using multinomial and binominal logistic regression models. The level of education of the adult has a high probability of influencing the consumption of unhealthy or healthy foods, it has a significant probability of exerting influence on social or medical problems and a correlation was found between the level of academic education and the pattern of dental visits. The development of health-promoting behaviors begins in childhood and involves parents, who have an essential role in the education of their children. Oral health promotion programs in schools need to target the child-adult-teacher-dentist relationships. Taking into consideration the aforementioned, a threefold viewpoint is necessary for the development of a national program aimed at promoting the oral health of schoolchildren in Romania.

6.
Nanomaterials (Basel) ; 14(10)2024 May 20.
Article in English | MEDLINE | ID: mdl-38786851

ABSTRACT

Metal nanoparticle phytosynthesis has become, in recent decades, one of the most promising alternatives for the development of nanomaterials using "green chemistry" methods. The present work describes, for the first time in the literature, the phytosynthesis of silver nanoparticles (AgNPs) using extracts obtained by two methods using the aerial parts of Marrubium vulgare L. The extracts (obtained by classical temperature extraction and microwave-assisted extraction) were characterized in terms of total phenolics content and by HPLC analysis, while the phytosynthesis process was confirmed using X-ray diffraction and transmission electron microscopy, the results suggesting that the classical method led to the obtaining of smaller-dimension AgNPs (average diameter under 15 nm by TEM). In terms of biological properties, the study confirmed that AgNPs as well as the M. vulgare crude extracts reduced the viability of human gingival fibroblasts in a concentration- and time-dependent manner, with microwave-assisted extracts having the more pronounced effects. Additionally, the study unveiled that AgNPs transiently increased nitric oxide levels which then decreased over time, thus offering valuable insights into their potential therapeutic use and safety profile.

7.
Healthcare (Basel) ; 12(7)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38610195

ABSTRACT

Our professional activity is constantly under pressure from a multitude of elements and factors that can be classified into the four components of the VUCA phenomenon-volatility, uncertainty, complexity, and ambiguity-components that define the turbulence and challenges of the external environment. Considering the general elements of this phenomenon, we designed a new VUCA dimension specific to the healthcare field within which we have identified and analyzed all the factors that can influence the main actors of the doctor-patient relationship and the effects that can occur within the healthcare system in which this relationship is born. In this context, we generated the VUCA treatment in healthcare capable of mitigating the impact of this phenomenon; this treatment involves essential elements in overcoming possible crises and vulnerabilities of the medical profession. The VUCA treatment in healthcare requires combating volatility, uncertainty, complexity, and ambiguity through vision, understanding, clarity, and agility, which are grounded in the doctor's need to acquire cross-functional competencies (soft skills). These competencies are applicable by using functional mechanisms and techniques that support the doctor in developing adaptability and anticipation skills, understanding the patient's needs and addressing them, and ensuring the functionality and efficiency of the healthcare system by transferring these elements from micro-management to macro-management levels.

8.
Healthcare (Basel) ; 12(2)2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38255086

ABSTRACT

This research analyzes the dental hygiene habits of schoolchildren from parents' perspectives, using the STEPS approach recommended by the World Health Organization. The key points of oral health care in children include the role of the family in encouraging and maintaining proper oral hygiene practices. This study aimed to assess the oral hygiene practices of schoolchildren with on-site dentists in Romania. Additionally, it sought to establish correlations between these behaviors and the educational levels of the adults with whom they live with. The participants were selected from the zero grade to the eighth grade, totaling 3843students. Statistical analysis involved the application of Fisher's Exact Test and Z-tests with Bonferroni correction. Multinominal and binominal logistic regression models were employed to predict the impact of parents' education on children's oral health status and behavior. The oral health status of children evaluated by parents as poor was more frequent in children whose parents had a primary or gymnasium education (p < 0.001). Female adults with a university education evaluated the gum health of their children as very good to a much greater extent (41.7%, p < 0.001). Regarding the use of auxiliary means, the majority of parents with a university education mentioned that their children use dental floss (26.4% females/27.4% males) (p < 0.001), compared to those with primary education, where the percentage was only (1.2% males/3.5% females) (p < 0.001). The results of this study highlight that the education level of the adults with whom the children live with influences the perception of the teeth and gums health status, the frequency of oral hygiene, the use of fluoride toothpaste, and auxiliary brushing aids.

9.
J Clin Med ; 12(14)2023 Jul 12.
Article in English | MEDLINE | ID: mdl-37510762

ABSTRACT

Diagnosis is a key aspect in endodontic treatment, in a decade where invasive interventions are misapprehended as social tendency instead of medical necessity. All diagnostic facets should be considered before intending the operative phase. Intraoral endodontic radiology-based diagnosis has been shown to be limited. Periapical X-ray is the most used endodontic imaging, yet it does not provide high accuracy. Traditionally, dentists have been trained to diagnose a cyst by certain aspects (size, shape and appearance); hence, an assumption that teeth are affected by "periapical cyst" were subjected to unnecessary extraction or apicoectomy. The aim of this systematic review is to critically appraise the publications that relate the histological diagnosis of a periapical lesion (considered the gold standard) to intraoral X-ray investigation. Ovid Medline, PubMed, ScienceDirect, Mendeley and Scopus were searched for English-language studies comparing periapical diagnosis obtained by using two techniques (histopathology and X-ray). Sixteen articles were included for the final analysis (qualitative and quantitative evaluation) out of which only two supported the statement that periapical diagnosis can be coherently assessed through periapical imaging. Although there is not enough evidence to deliver a definitive conclusion, there are many publications that refute the diagnosis of a cyst via periapical X-ray.

10.
Healthcare (Basel) ; 11(9)2023 May 05.
Article in English | MEDLINE | ID: mdl-37174868

ABSTRACT

Oral health professionals' knowledge of sustainability is essential for promoting environmental protection in dental healthcare. This pilot study involved an online survey addressed to 70 dental private practitioners from Bucharest, Romania, to evaluate their awareness of the concept of sustainability in dentistry. The performed statistical analysis revealed that 41.4% of the participants were well aware of sustainability in dentistry, with older participants demonstrating significantly higher levels of such awareness (p = 0.001). Sustainability awareness among participants correlates positively with their knowledge of the negative environmental impacts of dental activity (p < 0.001) and with the concern for sustainable dentistry implementation in their workplace (p = 0.037). Improper biohazardous waste disposal was identified as the primary cause of negative environmental impact of dental practices by 87.1% of participants. Installing high energy-efficient dental equipment was selected as the most important action to implement sustainability in participants' dental practices (64.3%). Overall, 51.4% of the participants reported that the COVID-19 pandemic had a medium impact on their dental activity in terms of sustainability. Our study found that participants have a moderate level of awareness regarding sustainability in dentistry, highlighting the need for education on sustainability for oral health professionals.

11.
Healthcare (Basel) ; 11(7)2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37046933

ABSTRACT

This paper analyzes the phenomenon of defensive medical practice, starting from the doctor-patient relationship, and the behavioral and professional factors that can influence the proper functioning of this relationship and the healthcare system. We analyze medical malpractice, given the increase in the number of accusations, as an essential factor in triggering the defensive behavior of doctors, together with other complementary factors that emphasize the need for protection and safety of doctors. The possible consequences for the doctor-patient relationship that defensive practice can generate are presented and identified by analyzing the determining role of the type of health system (fault and no-fault). At the same time, we investigate the context in which overspecialization of medical personnel can generate a form of defensive practice as a result of the limiting effect on the performance of a certain category of operations and procedures. The increase in the number of malpractice accusations impacts the medical community-"the stress syndrome induced by medical malpractice"-turning doctors into collateral victims who, under the pressure of diminishing their reputational safety, practice defensively to protect themselves from future accusations. This type of defensive behavior puts pressure on the entire healthcare system by continuously increasing costs and unresolved cases, which impact patients by limiting access to medical services in the public and private sectors.

12.
Article in English | MEDLINE | ID: mdl-36767150

ABSTRACT

Dental education was severely challenged by the COVID-19 pandemic worldwide. The evaluation of the viewpoint of the dental teachers of the Faculty of Dentistry at "Carol Davila" University of Medicine and Pharmacy in Bucharest, Romania, on these exceptional circumstances' consequences was the objective of this paper. A cross-sectional study was conducted in April 2022, on the academic staff who reported their perceptions of the emotional and educational impact of the pandemic by completing a Google Forms questionnaire. Although a significant emotional impact of the pandemic was reported by over a third of the participants (31.2%), most of them being teachers of fifth-year dental students (p = 0.019), the perceived stress had an impact on the teaching performance in few of them (14%), the quality of sleep remaining unaffected in most of them (53.7%), whereas the level of anxiety was low (57%). An educational impact regarding the techno difficulties during the online transition was mentioned by few respondents (16.1%), with male teaching staff facing the fewest problems (p = 0.024), as well as low levels of difficulties in transmitting academic information (11.9), with men also being the most unaffected (p = 0.006). More than half of the participants (59.1%) rather see digital and/or virtual education during the pandemic as having adverse effects on the educational system, the most sceptical being teachers of the fifth (p = 0.001) and sixth years (p = 0.001). The COVID-19 pandemic affected the academic staff of the Faculty of Dentistry at "Carol Davila" University of Medicine and Pharmacy in Bucharest, Romania, not only at a personal level but also at a professional, pedagogical one, due to the introduction of the online teaching system followed by the hybrid one. Age group, gender, and teaching year differentiated the degree of emotional and educational impairment.


Subject(s)
COVID-19 , Pandemics , Humans , Male , COVID-19/epidemiology , Cross-Sectional Studies , Motivation , Education, Dental
13.
Medicina (Kaunas) ; 59(1)2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36676740

ABSTRACT

Background and Objectives: The ever more complex modern dental education requires permanent adaptation to expanding medical knowledge and new advancements in digital technologies as well as intensification of interdisciplinary collaboration. Our study presents a newly developed computerized method allowing virtual case simulation on modular digital dental models and 3D-printing of the obtained digital models; additionally, undergraduate dental students' opinion on the advanced method is investigated in this paper. Materials and Methods: Based on the digitalization of didactic dental models, the proposed method generates modular digital dental models that can be easily converted into different types of partial edentulism scenarios, thus allowing the development of a digital library. Three-dimensionally printed simulated dental models can subsequently be manufactured based on the previously obtained digital models. The opinion of a group of undergraduate dental students (n = 205) on the proposed method was assessed via a questionnaire, administered as a Google form, sent via email. Results: The modular digital models allow students to perform repeated virtual simulations of any possible partial edentulism cases, to project 3D virtual treatment plans and to observe the subtle differences between diverse teeth preparations; the resulting 3D-printed models could be used in students' practical training. The proposed method received positive feedback from the undergraduate students. Conclusions: The advanced method is adequate for dental students' training, enabling the gradual design of modular digital dental models with partial edentulism, from simple to complex cases, and the hands-on training on corresponding 3D-printed dental models.


Subject(s)
Models, Anatomic , Models, Dental , Humans , Education, Dental/methods , Printing, Three-Dimensional , Computer Simulation
14.
Germs ; 13(4): 373-380, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38361538

ABSTRACT

Dental pathologies of endodontic origin are varied in nature, and include infectious and non-infectious causes. Through this review, we aim to provide a deeper understanding of the role of bacterial involvement and in the pathogenesis of endodontic pathologies, by reviewing the relevant literature on the most common bacterial species involved, and their capacity to organize as biofilms. Furthermore, we focus on the most important recent updates in the management of endodontic infections, from a multidisciplinary perspective.

15.
Vaccines (Basel) ; 10(10)2022 Oct 20.
Article in English | MEDLINE | ID: mdl-36298620

ABSTRACT

Vaccination hesitancy (VH) is a phenomenon which increases the occurrence of vaccine-preventable diseases. The study tests the validity of the Multidimensional Vaccine Hesitancy Scale (MVHS) in the case of a sample of Romanian adults (n = 528; Meanage = 30.57). The latter filled in an online cross-sectional survey. The construct validity of MVHS was assessed by using confirmatory factor analysis (CFA), the reliability was calculated by using the internal consistency, and the convergent and discriminant validity was assessed by using the composite reliability (CR), and average variance extracted (AVE). The obtained model was invariant across gender. The structural equation model was designed for predictive validity by using the partial least square method (PLS-SEM) which analyses the relation between the MVHS dimensions and the vaccination willingness. The results show support for the 8-factor structure of the scale (χ2/df = 2.48; CFI = 0.95; RMSEA = 0.053). The Cronbach's coefficients α > 0.70; McDonald's ω > 0.70 and CR > 0.80 have very good values. The structural equation model shows that there are more dimensions of the scale which predict vaccination hesitancy in various types of vaccines­the main predictors remain the dimensions of health risk and healthy condition. The study's conclusion led to the idea that the MVHS is suitable for medical practice and for research on the analysis of vaccination behaviours and intentions.

16.
Materials (Basel) ; 15(17)2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36079421

ABSTRACT

Dental endo-osseous implants have become a widely used treatment for replacing missing teeth. Dental implants are placed into a surgically created osteotomy in alveolar bone, the healing of the soft tissue lesion and the osseointegration of the implant being key elements to long-term success. Autophagy is considered the major intracellular degradation system, playing important roles in various cellular processes involved in dental implant integration. The aim of this review is an exploration of autophagy roles in the main cell types involved in the healing and remodeling of soft tissue lesions and implant osseointegration, post-implant surgery. We have focused on the autophagy pathway in macrophages, endothelial cells; osteoclasts, osteoblasts; fibroblasts, myofibroblasts and keratinocytes. In macrophages, autophagy modulates innate and adaptive immune responses playing a key role in osteo-immunity. Autophagy induction in endothelial cells promotes apoptosis resistance, cell survival, and protection against oxidative stress damage. The autophagic machinery is also involved in transporting stromal vesicles containing mineralization-related factors to the extracellular matrix and regulating osteoblasts' functions. Alveolar bone remodeling is achieved by immune cells differentiation into osteoclasts; autophagy plays an important and active role in this process. Autophagy downregulation in fibroblasts induces apoptosis, leading to better wound healing by improving excessive deposition of extracellular matrix and inhibiting fibrosis progression. Autophagy seems to be a dual actor on the scene of dental implant surgery, imposing further research in order to completely reveal its positive features which may be essential for clinical efficacy.

17.
Int J Immunopathol Pharmacol ; 36: 3946320221125090, 2022.
Article in English | MEDLINE | ID: mdl-36121435

ABSTRACT

Burn healing should be regarded as a dynamic process consisting of two main, interrelated phases: (a) the inflammatory phase when neutrophils and monocytes infiltrate the injury site, through localized vasodilation and fluid extravasation, and (b) the proliferative-remodeling phase, which represents a key event in wound healing. In the skin, both canonical autophagy (induced by starvation, oxidative stress, and environmental aggressions) and non-canonical or selective autophagy have evolved to play a discrete, but, essential, "housekeeping" role, for homeostasis, immune tolerance, and survival. Experimental data supporting the pro-survival roles of autophagy, highlighting its Yang, luminous and positive feature of this complex but insufficient explored molecular pathway, have been reported. Autophagic cell death describes an "excessive" degradation of important cellular components that are necessary for normal cell function. This deadly molecular mechanism brings to light the darker, concealed, Yin feature of autophagy. Autophagy seems to perform dual, conflicting roles in the angiogenesis context, revealing once again, its Yin-Yang features. Autophagy with its Yin-Yang features remains the shadow player, able to decide quietly whether the cell survives or dies.


Subject(s)
Autophagy , Burns , Homeostasis , Humans , Oxidative Stress , Wound Healing
18.
Materials (Basel) ; 15(9)2022 Apr 23.
Article in English | MEDLINE | ID: mdl-35591410

ABSTRACT

A provisionalization sequence is essential for obtaining a predictable final prosthetic outcome. An assessment of the mechanical behavior of interim prosthetic materials could orient clinicians towards selecting an appropriate material for each clinical case. The aim of this study was to comparatively evaluate the mechanical behavior-with compressive and three-point flexural tests-of certain 3D-printed and conventional resins used to obtain interim fixed dental prostheses. Four interim resin materials were investigated: two 3D-printed resins and two conventional resins (an auto-polymerized resin and a pressure/heat-cured acrylic resin). Cylindrically shaped samples (25 × 25 mm/diameter × height) were obtained for the compression tests and bar-shaped samples (80 × 20 × 5 mm/length × width × thickness) were produced for the flexural tests, observing the producers' recommendations. The resulting 40 resin samples were subjected to mechanical tests using a universal testing machine. Additionally, a fractographic analysis of failed samples in bending was performed. The results showed that the additive manufactured samples exhibited higher elastic moduli (2.4 ± 0.02 GPa and 2.6 ± 0.18 GPa) than the conventional samples (1.3 ± 0.19 GPa and 1.3 ± 0.38 GPa), as well as a higher average bending strength (141 ± 17 MPa and 143 ± 15 MPa) when compared to the conventional samples (88 ± 10 MPa and 76 ± 7 MPa); the results also suggested that the materials were more homogenous when produced via additive manufacturing.

19.
Materials (Basel) ; 15(3)2022 Jan 28.
Article in English | MEDLINE | ID: mdl-35160962

ABSTRACT

The purpose of this study is to outline relevant elements regarding the biochemical interactions between prosthetic materials used for obtaining implant-supported restorations and the oral environment. Implant-supported prostheses have seen unprecedented development in recent years, benefiting from the emergence of both new prosthetic materials (with increased biocompatibility and very good mechanical behavior), and computerized manufacturing technologies, which offer predictability, accuracy, and reproducibility. On the other hand, the quality of conventional materials for obtaining implant-supported prostheses is acknowledged, as they have already proven their clinical performance. The properties of PMMA (poly (methyl methacrylate))-which is a representative interim material frequently used in prosthodontics-and of PEEK (polyether ether ketone)-a biomaterial which is placed on the border between interim and final prosthetic use-are highlighted in order to illustrate the complex way these materials interact with the oral environment. In regard to definitive prosthetic materials used for obtaining implant-supported prostheses, emphasis is placed on zirconia-based ceramics. Zirconia exhibits several distinctive advantages (excellent aesthetics, good mechanical behavior, biocompatibility), through which its clinical applicability has become increasingly wide. Zirconia's interaction with the oral environment (fibroblasts, osteoblasts, dental pulp cells, macrophages) is presented in a relevant synthesis, thus revealing its good biocompatibility.

20.
Rom J Morphol Embryol ; 62(1): 53-62, 2021.
Article in English | MEDLINE | ID: mdl-34609408

ABSTRACT

INTRODUCTION: Dental agenesis (DA), brings together the anodontia, oligodontia, hypodontia, characterized by a deficit in the development of a variable number of teeth. The objectives of the study were to illustrate the phenotypic variability of non-syndromic DA, to identify cases of DA with hereditary genetic transmission, and establish the mode of DA genetic pattern in these cases, together with the determination of DA prevalence in the population group study. PATIENTS, MATERIALS AND METHODS: The cross-sectional observational study was performed on a mixed population group, consisting of 861 Caucasian patients, between January 2018-December 2019. The clinical evaluation protocol of patients with DA, used to illustrate their phenotype, included the following stages: oral examination, photographic examination, and radiological examination. The evaluation protocol specific to the family genetic study of patients with DA, involved the following three stages: family survey, construction of the family tree and analysis of the pedigree structure. RESULTS: The prevalence of DA in the population group was 2.78%. Regarding the phenotype, DA mainly affected the upper arch (50% of cases); bilateral DA had a significantly increased incidence (83.33% of cases) compared to unilateral form; in most cases (75%), a patient lacked one to two teeth, the lack of two teeth being the most common form (83.33% of cases); the upper lateral incisors were the teeth most frequently involved in DA (31.11% of the total missing teeth). Regarding the family genetic study, hereditary DA with autosomal dominant inheritance was present in 37.50% of cases. In the other cases (62.50%), isolated, sporadic forms of DA were registered, suggesting a spontaneous de novo mutation or a disorder of odontogenesis of a non-genetic nature. CONCLUSIONS: We consider that this study is of interest for current scientific research with applicability in dental medicine, by bringing actual information on the prevalence of non-syndromic DA in South-East Romania, the variety of phenotypic spectrum of DA for this geographic area, and the role of heredity in the DA genetic determinism in the studied population.


Subject(s)
Anodontia , Algorithms , Anodontia/diagnostic imaging , Anodontia/genetics , Cross-Sectional Studies , Humans , Incisor , Phenotype
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