Antimicrobial Efficiency of Pistacia lentiscus L. Derivates against Oral Biofilm-Associated Diseases-A Narrative Review.

Pistacia lentiscus L. (PlL) has been used for centuries in traditional medicine. The richness in antimicrobial biomolecules of Pll derivates can represent an alternative to chemically formulated agents used against oral infections. This review summarizes the knowledge on the antimicrobial activity of PlL essential oil (EO), extracts, and mastic resin against microorganisms being of relevance in oral biofilm-associated diseases. Results demonstrated that the potential of PlL polyphenol extracts has led to increasing scientific interest. In fact, the extracts are a significantly more effective agent than the other PlL derivates. The positive findings regarding the inhibition of periodontal pathogens and C. albicans, together with the antioxidant activity and the reduction of the inflammatory responses, suggest the use of the extracts in the prevention and/or reversal of intraoral dysbiosis. Toothpaste, mouthwashes, and local delivery devices could be effective in the clinical management of these oral diseases

Adhesive Restorations and the Oral Environmental Behaviour

Adhesive restorations are based on the use of materials, which have the capacity to bond tooth effectively. This is possible due to a polymerizing hybrid layer interface created by the use of the Etch&Rinse (ERAs) and self-etching adhesives (SEAs). Bonding using ERAs include the acid-etching removal of the mineral phase from the substrates of enamel and dentine. A hybrid layer results by filling the voids left by minerals by means of adhesive monomers. However, etching dentine may result in too much demineralization and wetness with discrepancies in reinforcement at the bottom of hybrid layer. SEAs avoid the separate etching phase of ERAs using acidic functional monomers. In the two-step SEAs, hybridization is created by the application of a primer of different pH acidity, followed by an adhesive resin. In the ‘One-Step SEAs’, acidic and adhesive monomers are mixed in the same bottle thereby causing hybridization at the same time. 10-MDP mild SEAs represent the better bonding technology in dentistry due to the ability to form a strong chemical bond in tooth tissue. However, adhesive restorations have high vulnerability in the oral environment, which have been attributed to the esterase activity of Streptococcus mutans and hydrolysis by matrix metalloproteinase

Xerostomia induced by radiotherapy: an overview of the physiopathology, clinical evidence, and management of the oral damage

Background: The irradiation of head and neck cancer (HNC) often causes damage to the salivary glands. The resulting salivary gland hypofunction and xerostomia seriously reduce the patient’s quality of life. Purpose: To analyze the literature of actual management strategies for radiation-induced hypofunction and xerostomia in HNC patients. Methods: MEDLINE/PubMed and the Cochrane Library databases were electronically evaluated for articles published from January 1, 1970, to June 30, 2013. Two reviewers independently screened and included papers according to the predefined selection criteria. Results: Sixty-one articles met the inclusion criteria. The systematic review of the literature suggests that the most suitable methods for managing the clinical and pathophysiological consequences of HNC radiotherapy might be the pharmacological approach, for example, through the use of cholinergic agonists when residual secretory capacity is still present, and the use of salivary substitutes. In addition, a modified diet and the patient’s motivation to enhance oral hygiene can lead to a significant improvement. Conclusion: Radiation-induced xerostomia could be considered a multifactorial disease. It could depend on the type of cancer treatment and the cumulative radiation dose to the gland tissue. A preventive approach and the correct treatment of the particular radiotherapeutic patient can help to improve the condition of xerostomia

Osteogenesis from Dental Pulp Derived Stem Cells: A Novel Conditioned Medium Including Melatonin within a Mixture of Hyaluronic, Butyric, and Retinoic Acids

Human dental pulp stem cells (hDPSCs) have shown relevant potential for cell therapy in the orthopedic and odontoiatric fields. The optimization of their osteogenic potential is currently a major challenge. Vascular endothelial growth factor A (VEGF A) has been recently reported to act as a major conductor of osteogenesis in vitro and in vivo. Here, we attempted to prime endogenous VEGF A expression without the need for viral vector mediated gene transfer technologies. We show that hDPSCs exposure to a mixture of hyaluronic, butyric, and retinoic acids (HA + BU + RA) induced the transcription of a gene program of osteogenesis and the acquirement of an osteogenic lineage. Such response was also elicited by cell exposure to melatonin, a pleiotropic agent that recently emerged as a remarkable osteogenic inducer. Interestingly, the commitment to the osteogenic fate was synergistically enhanced by the combinatorial exposure to a conditioned medium containing both melatonin and HA + BU + RA. These in vitro results suggest that in vivo osteogenesis might be improved and further studies are needed

Phenolic compounds in extra virgin olive oil stimulate human osteoblastic cell proliferation

In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11–16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18–22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9–13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly

HSF1 is a prognostic determinant and therapeutic target in intrahepatic cholangiocarcinoma

Background Intrahepatic cholangiocarcinoma (iCCA) is a lethal primary liver tumor characterized by clinical aggressiveness, poor prognosis, and scarce therapeutic possibilities. Therefore, new treatments are urgently needed to render this disease curable. Since cumulating evidence supports the oncogenic properties of the Heat Shock Factor 1 (HSF1) transcription factor in various cancer types, we investigated its pathogenetic and therapeutic relevance in iCCA.MethodsLevels of HSF1 were evaluated in a vast collection of iCCA specimens. The effects of HSF1 inactivation on iCCA development in vivo were investigated using three established oncogene-driven iCCA mouse models. In addition, the impact of HSF1 suppression on tumor cells and tumor stroma was assessed in iCCA cell lines, human iCCA cancer-associated fibroblasts (hCAFs), and patient-derived organoids. Results Human preinvasive, invasive, and metastatic iCCAs displayed widespread HSF1 upregulation, which was associated with a dismal prognosis of the patients. In addition, hydrodynamic injection of a dominant-negative form of HSF1 (HSF1dn), which suppresses HSF1 activity, significantly delayed cholangiocarcinogenesis in AKT/NICD, AKT/YAP, and AKT/TAZ mice. In iCCA cell lines, iCCA hCAFs, and patient-derived organoids, administration of the HSF1 inhibitor KRIBB-11 significantly reduced proliferation and induced apoptosis. Cell death was profoundly augmented by concomitant administration of the Bcl-xL/Bcl2/Bcl-w inhibitor ABT-263. Furthermore, KRIBB-11 reduced mitochondrial bioenergetics and glycolysis of iCCA cells. Conclusions The present data underscore the critical pathogenetic, prognostic, and therapeutic role of HSF1 in cholangiocarcinogenesis

Ultrastructural transmission electron microscopy (TEM) study of hybrid layers formed beneath a one-bottle adhesive system using the total-etch technique and a self-etching system

OBJECTIVE: To compare, using transmission electron microscopy (TEM), the ultrastructure of the hybrid layers formed beneath a one-bottle adhesive system using the total-etch technique with that of a self-etching system. METHOD AND MATERIALS: Occlusal cavity preparations were made in vivo in 18 human premolars and randomly appointed to three groups (n = 6), according to the following bonding procedures: (1) OptiBond Solo, a single-bottle adhesive system, was applied following 15 seconds etching with 37% phosphoric acid and rinsing; (2) Clearfil Liner Bond 2V, a self-etching adhesive system was applied; and (3) no bonding material was used, with the untreated smear layer acting as a control. The cavities were then filled with resin composite restorations. RESULTS: In group 1, dense resin tags obturated the tubules. A layer of inorganic silicon microgranules formed at the top of the interdiffusion zone, and below this was a zone of loosely arranged collagen fibers. Toward the base, there was a more dense accumulation of hydroxyapatite crystals. In group 2, dense resin tags obturated the tubular orifices. Collagen fibers were densely compacted within monomer material. Toward the base, hydroxyapatite crystals were observed between collagen bundles. In group 3, a rough fragmented smear layer covered the dentinal floor and occluded the tubules. CONCLUSION: Irregularities occurred in the coronal zone of the hybrid layer in both systems. In the one-bottle system, this was attributed to the etching technique, while in the case of the self-etching system, this was attributed to the resin materials. These irregularities are potential sites for debonding in the clinical situation

In Vitro Effect of Instrumentation Using Ultrasonication with and without Hydrogen Peroxide on the Removal of Biofilms and Spread of Viable Microorganisms in Aerosols.

PURPOSE To evaluate the use of hydrogen peroxide as an adjunct to ultrasonication (US) in biofilm removal and whether it can limit the spread of viable microorganisms in the aerosol. MATERIALS AND METHODS Multi-species biofilms were formed on dentin disks and titanium disks fixed on a plastic surface. After placing the specimens in a periodontal pocket model, an ultrasonic scaler was applied for 30 s, in part combined with 0.25% or 0.5% H2O2. After treatment, the remaining biofilm was analysed for bacterial counts (colony forming units [CFU]), biofilm quantity and metabolic activity. Further, the cytotoxic effect of hydrogen peroxide on periodontal ligament fibroblasts was assessed and the spread of bacteria in aerosol was quantified. RESULTS Ultrasonication reduced bacterial counts in biofilm, biofilm mass and metabolic activity on both dentin and titanium disks. Adjunctive use of 0.25% and 0.5% H2O2 more effectively reduced the viable bacteria in biofilm than ultrasonication alone; this was also found on both dentin and titanium. The different concentrations of H2O2 did not lead to corresponding differences in bacterial mass and metabolic activity. The spread of bacteria through aerosols was statistically significantly reduced when adjunctive H2O2 was used. However, a certain cytotoxic effect on periodontal ligament fibroblasts by H2O2 could not be ruled out. CONCLUSIONS Irrigating with H2O2 during periodontal instrumentation with an ultrasonic scaler increases the reduction of viable bacteria within biofilms. It might limit bacterial spreading via aerosols

Effectiveness of Two Self-Etchings Bonded Clinically in Caries Affected Dentin with Homogeneous Smear Layer

Aim. To examine the interface of two self-etchings in carious affected dentin (CAD), under clinical conditions. Materials and Methods. Class I cavities were prepared in 21 carious premolars, refining them by the use of a fine diamond bur in order to create similar smear layer interference. The mild self-etching Clearfil SE Bond (CSE), pH = 2.0, and the strong Tyrian SPE-One Step Plus (TSO), pH = 0.5, were applied followed by a composite. Teeth were extracted and processed for TEM. The primer’s osmolarity of the self-etchings was also calculated using a microosmometer. Results. CSE hybrid layer retained smear layer residues and scattered crystallites as an effect of the mild acidity. A high presence of hydroxyapatite still protected the affected fibres within the hybrid layer. CSE primer demonstrated values of 3220 mOsm/kg. TSO interdiffusion showed strong demineralization. Resin tags were not formed in the dentinal tubules which remained obstructed by crystals. However, dissolution of peritubular dentin and porosities were observed in the intertubular regions. The osmolarity of TSO was 8200 mOsm/kg. Conclusion. Increasing the acidity and osmolarity of the self-etchings increases interference in the homogeneous reinforcement of CAD, which may predispose the hybrid layer to instability and hydrolytic degradation overtime