Identification of a miRNA Panel with a Potential Determinant Role in Patients Suffering from Periodontitis.

In recent years, the role of microRNA (miRNA) in post-transcriptional gene regulation has advanced and supports strong evidence related to their important role in the regulation of a wide range of fundamental biological processes. Our study focuses on identifying specific alterations of miRNA patterns in periodontitis compared with healthy subjects. In the present study, we mapped the major miRNAs altered in patients with periodontitis (n = 3) compared with healthy subjects (n = 5), using microarray technology followed by a validation step by qRT-PCR and Ingenuity Pathways Analysis. Compared to healthy subjects, 159 differentially expressed miRNAs were identified among periodontitis patients, of which 89 were downregulated, and 70 were upregulated, considering a fold change of ±1.5 as the cut-off value and p ≤ 0.05. Key angiogenic miRNAs (miR-191-3p, miR-221-3p, miR-224-5p, miR-1228-3p) were further validated on a separate cohort of patients with periodontitis versus healthy controls by qRT-PCR, confirming the microarray data. Our findings indicate a periodontitis-specific miRNA expression pattern representing an essential issue for testing new potential diagnostic or prognostic biomarkers for periodontal disease. The identified miRNA profile in periodontal gingival tissue was linked to angiogenesis, with an important molecular mechanism that orchestrates cell fate.

Association of Graphene Silver Polymethyl Methacrylate (PMMA) with Photodynamic Therapy for Inactivation of Halitosis Responsible Bacteria in Denture Wearers.

(1) Background: Poor hygiene and denture presence in the oral cavity are factors that favor bacterial accumulation, the cause of halitosis and of various oral and general diseases. Aim: This study aimed to evaluate the possibility of inactivating bacteria associated with halitosis in acrylic denture wearers using polymethyl methacrylate resin enhanced with graphene silver nanoparticles and the effect of the resin association with extra oral photodynamic therapy. (2) Methods: Graphene silver nanoparticles in 1 and 2 wt% were added to a commercial acrylic resin powder. Three study groups containing samples from the three different materials were established. The first group was not exposed to the light treatment, and the other two were exposed to red light (laser and light emitting diode) after photosensitizer placement on the disk's surface. Samples were incubated with Porphyromonas gingivalis and Enterococcus faecalis. (3) Results: For both bacterial strains, inhibition zones were obtained, showing significant differences for the light-treated samples. (4) Conclusions: Denture resins with antibacterial properties associated with extra oral photodynamic therapy exhibited enhanced antibacterial effects. The procedure could be used as a safer and more efficient alternative technique against halitosis and oral infections in denture wearers.

Atomic force microscopy analysis of the surface alterations of enamel, dentin, composite and ceramic materials exposed to low oral pH in GERD.

Dental erosion is a significant topic in medical literature, both for gastroenterology and dental medicine. Dental structure loss has a psychosocial and functional significance. The pathogenesis of dental erosion in patients diagnosed with gastroesophageal reflux disease (GERD) characterized by the presence of an acidic oral environment after reflux episodes, is not well understood. The present study was designed to observe the effect of low oral pH in time on natural surfaces including enamel and dentine, but also on materials used in treating these dental destructions such as composites and ceramics. The acidic oral environment was estimated in relation to salivary pH. In the dental laboratory, 5-mm2 and 1-mm composite pieces of thick enamel, dentine, Emax Ceramic and Nexco Ivoclar were cut in order to be analyzed using atomic force microscopy (AFM) and to observe the surface alterations. Gastric acid was collected and mixed with saliva until a pH value of 6.0 was obtained, in which the pieces were immersed for 24, 120, 240 h. Roughness of each surface was calculated at a microstructure and nanostructure level. The results showed significant alterations in enamel and dentine exposed to a lower pH level beginning even at a short immersion time, in comparison with composites and ceramics which had no alterations. In conclusion, multidisciplinary attention should be given to detect and manage acidity of the oral cavity caused by GERD, in order to prevent dental erosion.

Oral Hygiene Habits of Complete Denture Wearers in Central Transylvania, Romania.

PURPOSE: To identify the oral hygiene habits and denture hygiene status (e.g. sociodemographic characteristics, general health status) of complete denture wearers in Central Transylvania, Romania. MATERIALS AND METHODS: This descriptive cross-sectional study was based on an original self-administered questionnaire. It included 162 patients who experienced complete tooth loss in one or both jaws and wore polymethylmethacrylate acrylic (PMMA) complete dentures. The exclusion criteria were partial dentures, dentures fabricated from materials other than PMMA, and the patient being unable to provide all the required information. The questionnaire solicited information regarding sociodemographic status, general health and oral hygiene-related habits. The dentures were clinically evaluated in order to assess denture hygiene. RESULTS: Most respondents were completely edentulous (38.0% wore maxillary dentures, 10.6% mandibular dentures, while 51.6% had both), with an average age above 60, all wearing dentures. The clinical evaluation of the dentures revealed that 12.3% exhibited optimal hygiene status, 40.1% good, 32.7% unsatisfactory and 14.8% bad, with more women than men having well-cleaned dentures. Cleaning frequency was found to be 2-3 times per day for 54.3% of the patients, with 93.2% of the subjects using a toothbrush and 76.5% using toothpaste. Most of the participants felt at ease with the cleaning procedures. Only 30.9% of the respondents reported denture removal overnight. The results showed that the hygiene of the patients' dentures was not correlated with their answers regarding oral hygiene habits. CONCLUSIONS: Competent oral health and denture hygiene promotion should be established, especially regarding nocturnal denture removal, denture hygiene methods, instruments and cleaning frequency.

Flexural strength, biocompatibility, and antimicrobial activity of a polymethyl methacrylate denture resin enhanced with graphene and silver nanoparticles.

OBJECTIVE: The study evaluates the effect of adding graphene-Ag nanoparticles (G-AgNp) to a PMMA auto-polymerizing resin, with focus on antibacterial activity, cytotoxicity, monomer release, and mechanical properties. MATERIALS AND METHODS: Auto-polymerizing acrylic resin (M) was loaded with 1 wt% G-AgNp (P1) and 2 wt% G-AgNp (P2). Methyl methacrylate monomer release (MMA) was measured after immersion of the samples in chloroform and cell medium respectively. Cell viability was assessed on dysplastic oral keratinocytes (DOK) and dental pulp stem cells. Oxidative stress and inflammatory response following exposure of dysplastic oral keratinocytes to the experimental resins was evaluated. Antibacterial activity against Staphylococcus aureus, Streptococcus mutans and Escherichia coli and also flexural strength of the resins were assessed. RESULTS: Residual monomer: For samples immersed in chloroform, MMA concentration reached high levels, 10.27 µg/g for sample P1; MMA increased at higher G-AgNp loading; 0.63 µg/g MMA was found in medium for P1, and less for sample P2. Cell viability: Both cell lines displayed a viability decrease, but remained above 75%, compared to controls, when exposed to undiluted samples. Inflammation: proinflammatory molecule TNF-α decreased when DOK cultures were exposed to G-AgNp samples. MDA levels indicated increased oxidative stress damage in cells treated with PMMA, confirmed by the antioxidant mechanism activation, while samples containing G-AgNp induced an antioxidant effect. All tested samples showed antibacterial properties against Gram-positive bacteria. Samples containing G-AgNp also exhibited bactericide action on E. coli. Mechanical properties: both samples containing G-AgNp improved flexural strength compared to the sample resin, measured through elastic strength parameters. CONCLUSIONS: PMMA resin loaded with G-AgNp presents promising antibacterial activity associated with minimal toxicity to human cells, in vitro, as well as improved flexural properties. CLINICAL RELEVANCE: These encouraging results obtained in vitro support further in vivo investigation, to thoroughly check whether the PMMA loaded with graphene-silver nanoparticles constitute an improvement over current denture materials.

The Role of Angiogenesis and Pro-Angiogenic Exosomes in Regenerative Dentistry.

Dental surgeries can result in traumatic wounds that provoke major discomfort and have a high risk of infection. In recent years, density research has taken a keen interest in finding answers to this problem by looking at the latest results made in regenerative medicine and adapting them to the specificities of oral tissue. One of the undertaken directions is the study of angiogenesis as an integrative part of oral tissue regeneration. The stimulation of this process is intended to enhance the local availability of stem cells, oxygen levels, nutrient supply, and evacuation of toxic waste. For a successful stimulation of local angiogenesis, two major cellular components must be considered: the stem cells and the vascular endothelial cells. The exosomes are extracellular vesicles, which mediate the communication between two cell types. In regenerative dentistry, the analysis of exosome miRNA content taps into the extended communication between these cell types with the purpose of improving the regenerative potential of oral tissue. This review analyzes the stem cells available for the dentistry, the molecular cargo of their exosomes, and the possible implications these may have for a future therapeutic induction of angiogenesis in the oral wounds.

Dental erosion in gastro-esophageal reflux disease. A systematic review.

The growing interest reflected in the studies on dental erosion is justified by the severe health problems it entails, i.e. esthetic, phonetic, masticatory disturbances and pulp complications. Most studies investigate the prevalence of dental erosion in adults and children, the severity of lesions and etiopathogenetic factors. BACKGROUND AND AIM: Dental erosions (DE) are one of the extraesophageal complications of gastroesophageal reflux disease (GERD). An increasing amount of papers shed light on this topic. We carried out a systematic review on the association between GERD and DE. METHODS: We studied the association between DE and GERD in adults and children. The search for published studies was performed in PubMed using search terms "dental erosion" and "gastro-esophageal reflux disease". References published since 2007 were included and a systematic review was carried out. Articles not assessing DE in GERD patients were excluded, and also case presentations and articles in languages of limited circulation. The prevalence of DE in patients with GERD, extrinsic and intrinsic etiological factors of DE and the severity of dental erosion lesions were analyzed. RESULTS: A total of 273 articles were found, 10 studies being retained for analysis. Correlations between DE and GERD, namely the prevalence and severity of dental erosion in GERD patients, were investigated. DE prevalence was between 10.6% - 42%, median 25.5%. Mean values of DE prevalence were 48.81% in GERD patients, compared to 20.48% in non-GERD controls. Comparative values of DE frequency in adults with GERD was 38.96%, compared to 98.1% in children with GERD. CONCLUSIONS: DE is a condition associated with GERD. DE prevalence is higher in GERD patients. Intrinsic pathogenetic factors with direct action on the hard dental tissues are GERD, while extrinsic factors are represented by diet. Among the patients diagnosed with GERD, youth under the age of 18 had a higher frequency compared to adults.

Antibacterial and antifungal activity of endodontic intracanal medications.

BACKGROUND AND AIMS: The sterilization of the entire root canal system represents the main goal of every endodontist, given the fact that the control of the microbial flora is the key point of every root canal treatment. The diversity of microorganisms found inside the root canal and also the resistance of some bacterial species to intracanal medications led to a continuous development of new endodontic products. The present study focuses on the comparison of the antibacterial and antifungal properties of different endodontic products, two commercially available, one experimental plant based extract, and two control substances. METHODS: The disc diffusion assay was used to determine the antibacterial and antifungal properties of chlorhexidine, calcium hydroxide, a mix extract between Arctium lappa root powder and Aloe barbadensis Miller gel, Amoxicillin with clavulanic acid and Fluconazole (as control substances). Two of the most common microorganisms found in endodontic infections were chosen: Enterococcus faecalis (ATCC 29212) and Candida albicans ATCC(10231). RESULTS: All tested substances showed inhibition zones around the discs, for Enterococcus faecalis and Candida albicans, including the experimental mix extract of Arctium lappa root powder with Aloe vera gel. CONCLUSION: The experimental mix extract of Arctium lappa root powder and Aloe vera gel is able to inhibit very resistant microorganisms, like Enterococcus faecalis and Candida albicans.

Shade Correspondence, Color, and Translucency Differences between Human Dentine and a CAD/CAM Hybrid Ceramic System.

OBJECTIVE: To determine the shade correspondence between human dentine and two versions of a CAD/CAM hybrid ceramic system and to investigate color and translucency differences between these materials. MATERIALS AND METHODS: Twenty-four samples of different shades and opacities were fabricated from Vita Enamic CAD/CAM ceramic blocks. Human dentine samples were obtained from 73 extracted maxillary teeth. Color coordinates of all samples were measured using VitaEasyshade spectrophotometer. The translucency parameter (TP) and ΔEab* and ΔE00 color differences, with respect to human dentine of anterior and posterior teeth, were calculated. RESULTS: Vita Enamic Translucent was the best match for anterior teeth (>90% of cases) while Vita Enamic T 3M2 was the best option for the dentine samples of posterior teeth in 78.8% ( ΔEab*) and 54.5% ( ΔE00) of the cases. The smallest differences in translucency ( ΔTP) with the dentine samples of anterior teeth were obtained for Vita Enamic T 3M2 (92.5%) and with those of posterior teeth for Vita Enamic HT 1M2 (45.4%). CONCLUSIONS: VITA Enamic Translucent is the best option as color match for both anterior and posterior teeth dentine. In terms of translucency, VITA Enamic Translucent closely matched anterior teeth dentine while for posterior teeth, VITA Enamic HT was the best option. CLINICAL SIGNIFICANCE: The results of the present study could help clinicians in their decision of choosing a specific shade and translucency for their anterior or posterior esthetic restorations with hybrid ceramics. (J Esthet Restor Dent 28:S46-S55, 2016).

Dentine scattering, absorption, transmittance and light reflectivity in human incisors, canines and molars.

OBJECTIVES: To evaluate, using Kubelka-Munk reflectance theory, the scattering (S), absorption (K), transmittance (T) and light reflectivity (RI) of incisors, canines and molars human dentine. METHODS: Eighty-one human teeth (incisors, canines and molars) were used in this study. All teeth crowns were sectioned using a water-cooled diamond saw at low speed. The obtained dentine samples were polished to a final thickness of 2mm. The relative spectral radiance was measured against black and white backgrounds, using a spectroradiometer in a viewing cabinet with D65 illuminant. Kubelka-Munk equations were used to calculate the scattering and absorption coefficients, transmittance and light reflectivity. Kruskal-Wallis rank sum test was performed to compare the mean values of Kubelka-Munk coefficients of human incisors, canines and molars dentine samples followed by Kruskal-Wallis multiple comparison tests for pairwise comparisons. RESULTS: The spectral behavior of S, T and RI exhibited similar trends for all three types of dentine samples. However, highly significant differences (p<0.001) were found between their magnitudes in the three types of dentine samples (p<0.001). Only the magnitudes of the K coefficients were found to be similar (p=0.235) between incisors, canines and molars. Canine's dentine samples showed highest S and RI values, while human molars dentine samples exhibited highest K and T values. CONCLUSIONS: Within the limitations of this study, the optical properties of human dentine are strongly influenced by the type of tooth. The results of the present study can be used as reference in the development of aesthetic dental restorative materials. CLINICAL IMPLICATIONS: The significant differences identified in the optical behavior of the dentine from the three types of teeth have to be taken into consideration by the dentist and the dental technician when pursuing biomimetics with any restorative material in esthetic dentistry.

Spectrophotometric color evaluation of permanent incisors, canines and molars. A cross-sectional clinical study.

BACKGROUND AND AIMS: An accurate color reproduction represents the final validation level of an esthetic anterior or posterior restoration. The aim of this study was to evaluate the color of permanent maxillary incisors, canines and molars, using a clinical spectrophotometer. METHODS: The Vita Easyshade Advance 4.0(®) intraoral spectrophotometer was used by one clinician to determine the color of 369 permanent maxillary incisors, canines and molars. The best matches to Vitapan Classical(®) and 3D-Master(®) shade guides were recorded. A one-way analysis of variance and Kruskal-Wallis test were used to compare L*, a*, b*, c* and h* color coordinates among the 3 types of teeth. Differences between the mean values of all color coordinates were evaluated by use of Bonferroni corrections. Color difference (ΔE*) between incisors, canines and molars was calculated from ΔL*, Δa* and Δb* data and the results were compared to ΔE*=3.3 acceptability threshold. RESULTS: Except for Δa* and Δh* between canines and molars, statistically significant differences among the mean differences of all color coordinates were found when the 3 types of teeth were compared by pairs. The most frequently measured shades were A1 (48.4%), respectively 1M1 (31.5%) for incisors, B3 (36.6%), respectively 2M3 (39.8%) for canines and B3 (44.7%), respectively 2M3 (52%) for molars. Incisors had the highest lightness values, followed by canines and molars. Molars were the most chromatic with the highest a* and b* values. CONCLUSIONS: Despite the limitations of this study, color differences among incisors, canines and molars were found to be statistically significant, above the clinical acceptability threshold established. In conclusion, successful esthetic restorations of permanent teeth of the same patient need an individual color assessment and reproduction of every type of tooth.

The Influence of Root-End Filling Materials on Bone Healing - An Experimental Study.

AIMS: The aim of this experimental study is to assess the bone healing phenomenon produced in the presence of several dental materials: a polycarboxylate cement, a glass-ionomer cement, a composite resin and MTA (mineral trioxide aggregate) based cement. METHODS: The biocompatibility of four root-end fillings materials, used in periapical surgery was investigated after intra-osseous implantation of the materials in rats' calvaria. Tissue reaction was studied at 2, 4, 6, 8, 10 and 12 weeks after implantation. We took into consideration the presence of inflammatory cells (polymorphonuclear leukocytes, macrophages, plasma cells, lymphocytes and giant cells) and classified the aspects of the histological samples according to the following scale: 0 - no inflammation, 1 - mild, isolated inflammation, 2 - moderate, localized inflammatory reaction, 3 - severe, diffuse and intense inflammatory reaction. RESULTS: The inflammatory reaction was present at the six intervals for all the tested materials, but at 12 week interval, the reaction was minimal in all cases. Also, a dissolution reaction was observed for all the materials, less intense for glass-ionomer cement and polycarboxilate cement. CONCLUSIONS: At the end of the experimental period, glass-ionomer cement and polycarboxilate cement suffered a lesser dissolution reaction as compared to the second group of tested materials.

Apoptotic markers in photoinduced cutaneous carcinoma.

Cutaneous carcinomas are malignant lesions, which most commonly occur on photo-aggressed site. The purpose of our study was to evaluate the immunohistochemical expression of three apoptotic markers (p53, Bax, and Bcl-2) in photoinduced basal and squamous cell carcinoma. The study was performed on 24 patients diagnosed with these forms of cutaneous carcinoma localized on photoexposed regions: 14 cases of basal cell carcinoma (BCC) and 10 cases of squamous cell carcinoma (SCC), classified accordingly WHO 2003. The immunohistochemical study performed on the three proteins involved in the apoptotic process revealed certain specific features in their manner of expression, which do not correlate or respect the critical determinant rule (Bcl-2/Bax>1). Basal cell carcinoma expresses higher levels of Bcl-2, with a better prognosis, a less aggressive evolution, and no metastasis. Squamous cell carcinoma, on the other hand, expresses lower levels of Bcl-2, but the clinical outcome is more aggressive, the tumor has a faster evolution and may metastasize. P53 protein respects the profile given in literature data, having a higher score in squamous cell carcinoma versus basal cell carcinoma. According to the tumor localization on photo-aggressed sites, we have considered that ultraviolet rays play an important role in initiation of carcinogenesis through still occult mechanisms that may induce these particular or rather "bizarre" expressions of apoptotic markers.

[Treatment of arterio-venous high-flow vascular malformations of the mandible]. / Tratamentul malformatiilor vasculare arterio-venoase de flux înalt ale mandibulei.

Arterio-venous vascular malformations (AVM) rarely occur in craniofacial bones. The most frequent location has been reported in the mandible. The first clinical evidence of the lesions can be a fatal hemorrhage, occurring spontaneously or subsequent to dental therapy. Lack of knowledge about these lesions among specialists dealing with the oral and maxillofacial regions can lead to fatal complications. The study presents the successful multidisciplinary management of two cases of mandibular AVM using embolization, sclerotherapy and bone reconstruction, a major challenge owing to the substantial risk of morbidity, recurrence by recanalization and revascularization, neurologic deficits and mortality. There were no complications over a follow-up period of 12 years.