Mouthwashes: Alternatives and Future Directions.

This narrative review summarises "alternative" or "natural" over-the-counter (OTC) mouthwashes not covered elsewhere in this supplement and newly emerging products, as potential mouthwashes of the future. The "natural" mouthwashes reviewed include saltwater, baking soda, coconut oil, charcoal, propolis, seaweeds, and probiotics. Other than essential oils, it is apparent that their clinical effectiveness is still under debate, but there is some evidence to suggest that propolis reduces plaque and gingivitis. This review also covers the host immune response, via novel anti-inmmunomodulant mouthwashes, such as erythropoietin to reduce inflammation with oral mucositis (OM) after radiotherapy. The emerging concept of nanoparticle-containing mouthwashes, such as iron oxide, is further discussed for OM, this agent having the potential for more targeted delivery of chemical antimicrobials. Unfortunately, there are impacts on the environment of widening mouthwash use with more new products, including increased use of packaging, antimicrobial resistance, and possible detrimental effects on marine life. Further, there are roadblocks, relating to regularly approvals and side effects, that still need to be overcome for any OTC deivered immunomodulant or nanoformulation mouthwashes. Despite these caveats, there are many new mouthwashes under development, which could help manage major oral diseases such as caries, gingivitis, and periodontal disease.

Intracellular bacterial eradication using a novel peptide in vitro.

AIM: To determine the effect of a novel antimicrobial peptide (AMP; OP145) and cell-penetrating peptide (Octa-arginine/R8) conjugate on the killing of intracellular Enterococcus faecalis, compared to OP145 and an antibiotic combination recommended for regenerative endodontic procedures. METHODOLOGY: The biocompatible concentrations of OP145 and OP145-R8 were determined by assessing their cytotoxicity against human macrophages and red blood cells. Spatiotemporal internalization of the peptides into macrophages was investigated qualitatively and quantitatively by confocal laser scanning microscopy and flow cytometry respectively. Killing of extracellular and intracellular E. faecalis OG1RF by the peptides was determined by counting the colony-forming units (CFU). Intracellular antibacterial activity of the peptides was compared to a double antibiotic combination. Confocal microscopy was used to confirm the intracellular bacterial eradication. Significant differences between the different test groups were analysed using one-way analysis of variance. p < .05 was considered to be statistically significant. RESULTS: Peptides at a concentration of 7.5 µmol/L were chosen for subsequent experiments based on the results of the alamarBlue™ cell viability assay and haemolytic assay. OP145-R8 selectively internalized into lysosomal compartments and the cytosol of macrophages. Conjugation with R8 improved the internalization of OP145 into macrophages in a temporal manner (70.53% at 1 h to 77.13% at 2 h), while no temporal increase was observed for OP145 alone (60.53% at 1 h with no increase at 2 h). OP145-R8 demonstrated significantly greater extracellular and intracellular antibacterial activity compared to OP145 at all investigated time-points and concentrations (p < .05). OP145-R8 at 7.5 µmol/L eradicated intracellular E. faecalis after 2 h (3.5 log reduction compared to the control; p < .05), while the antibiotics could not reduce more than 0.5 log CFU compared to the control (p > .05). Confocal microscopy showed complete absence of E. faecalis within the OP145-R8 treated macrophages. CONCLUSIONS: The results of this study demonstrated that the conjugation of an AMP OP145 to a cell-penetrating peptide R8 eradicated extracellular and intracellular E. faecalis OG1RF without toxic effects on the host cells.

Influence of Coronal Flaring on the Shaping Ability of Two Heat-Treated Nickel-Titanium Endodontic Files: A Micro-Computed Tomographic Study.

Nickel-titanium (NiTi) usage is associated in endodontics with some complications including canal transportation. Centering ability of a NiTi file is the ability to stay centered in the root canal system during instrumentation. Any undesirable deviation from the natural canal path is indicated as canal transportation. A possible strategy to improve the centering ability of NiTi instruments is the pre-enlargement of the coronal third of the root canal to minimize coronal interferences. This procedure is known as coronal flaring. The aim of this study was to perform a micro-computed tomographic (micro-CT) evaluation of the effect of coronal flaring on canal transportation and centering ability of two heat treated nickel-titanium rotary instruments, 2Shape (Micro Mega, Besançon, France) and HyFlex CM (Coltène Whaledent, Altstätten, Switzerland). Thirty extracted mandibular molars with two independent mesial canals were selected and randomly instrumented (n = 15 canals) with One Flare (Micro Mega, Besançon, France) before HyFlex CM, HyFlex CM (without coronal flaring), One Flare before 2Shape and 2Shape (without coronal flaring). One Flare (Micro Mega, Besançon, France) was introduced 4 mm below the canal entrance for canals prepared with coronal flaring. HyFlex CM and 2Shape were used accordingly to manufacturers' instructions. New files were used for each canal. During and after instrumentation, irrigation procedures were performed. Micro-CT images were obtained pre- and post-preparation to measure and record root canal transportation and centralization. They were reconstructed from root apex to canal orifices, generating approximately 1000 sections per specimen. The anatomical thirds were determined by dividing the number of cross-sectional slices by three. Root canal transportation and centralization were determined by Gambil method, and the mean values were analyzed by repeated measures analysis of variance followed by multiple comparisons of Bonferroni to compare the different instrumentations procedures and the root thirds (p < 0.05). As for root canal transportation, 2Shape reported significantly higher values compared to HyFlex CM in the cervical region independently from the coronal flaring. In the apical region, 2Shape caused significantly minor canal transportation when used with coronal flaring with compared with the absence of coronal flaring. Regarding the centralization, HyFlex CM showed higher values than 2Shape in the cervical, independently from coronal flaring. In the apical region, 2Shape with coronal flaring exhibited significant major centering ratio, compared with not. Within the limitations of this study, coronal flaring reduced canal transportation and improved centralization of the 2Shape files in the apical section while it had no significant influence on shaping ability of the HyFlex CM instruments. Coronal flaring could represent a valid strategy to improve the shaping ability of NiTi files knowing that its benefit could be influenced by the shaping file used.

Present status and future directions: Minimally invasive root canal preparation and periradicular surgery.

Inspired by several other surgical disciplines, the quest for treating diseases through minimally invasive procedures has permeated endodontics, but not without controversy. Indeed, pulp amputation/excision and root-end resection are akin to surgical procedures elsewhere in the body and therefore, an increasing number of studies have addressed the "potential" to adopt such minimally invasive procedures in root canal treatment, with the larger goal of conserving tooth tissue for long-term survival of treated teeth. Yet, it is undeniable that this "trend" has been met with immense resistance with unclear evidence to strongly support or refute this philosophy. One may view root canal treatment as having two important procedural parts: (i) gaining access to the root canal and (ii) achieving clean root canals to remove the necrotic/infected or irreversibly inflamed tissues and then fill the space that was occupied by the pulp tissue and subsequently enlarged during cleaning and shaping, which should result in two key long-term outcomes: (i) healing of periradicular periodontitis and (ii) survival/retention of the tooth. Whilst a lot of interest has been directed towards gaining access through minimally invasive cavity designs, it is surprising that little effort has been expended on studying minimally invasive root canal preparation or surgical intervention. The aim of this review is not to promote or denigrate these philosophies, but to provide a balanced overview of the concepts, currently available evidence and future perspectives on minimally invasive endodontics from the context of root canal preparation and surgical endodontics. Specific attention is given to the role of modern irrigation strategies in potentially improving canal cleanliness even when canals are minimally prepared and the areas of research that are currently lacking in this topic.

Influence of kinematics and incidence angles on the cutting efficiency of two single-file nickel-titanium rotary instruments.

To compare the cutting efficiency of F6 Sky Taper (F6ST) and One Curve (OC) with different kinematics and cutting inclinations. Cutting efficiency of 80 new F6ST and OC was tested at 90° and 70° inclination in relation to the sample, in continuous rotation and reciprocation, against standardised gypsum samples for 120 seconds using a customised device. Data expressed as weight loss and length of the sample cut were analysed using two-way analysis of variance and Tukey t-test (P<.05). F6ST showed significantly higher cutting efficiency in reciprocation, while OC in continuous rotation. Regardless of inclination, F6ST showed statistically higher values than OC in reciprocation, while OC exhibited higher cutting ability in continuous rotation. The 70° inclination significantly improved the cutting efficiency of both files. Reciprocation improved the cutting efficiency of F6ST while continuous rotation enhanced cutting ability of OC. An inclined insertion improved the cutting ability, independently from the movement.

Photoluminescence-Based Bioassay With Cysteamine-Capped TiO2 Nanoparticles for the Selective Recognition of N-Acyl Homoserine Lactones.

Currently available diagnostic procedures for infections are laborious and time-consuming, resulting in a substantial financial burden by increasing morbidity, increased costs of hospitalization, and mortality. Therefore, innovative approaches to design diagnostic biomarkers are imperative to assist in the rapid and sensitive diagnosis of microbial infections. Acyl homoserine lactones (AHLs) are ubiquitous bacterial signaling molecules that are found to be significantly upregulated in infected sites. In this pioneering work, we have developed a simple photoluminescence-based assay using cysteamine-capped titanium oxide (TiO2) nanoparticles for AHL detection. The PL intensity variation of the oxygen defect state of TiO2 was used for the biosensing measurements. The bioassays were validated using two well-studied AHL molecules (C4-HSL and 3-oxo-C12 HSL) of an important human pathogen, Pseudomonas aeruginosa. The developed system has a maximum relative response of 98%. Furthermore, the efficacy of the system in simulated host urine using an artificial urine medium showed a linear detection range of 10-160 nM. Also, we confirmed the relative response and specificity of the system in detecting AHLs produced by P. aeruginosa in a temporal manner.

A curcumin-sophorolipid nanocomplex inhibits Candida albicans filamentation and biofilm development.

Candida albicans is an opportunistic fungal pathogen that is highly resistant to contemporary antifungals, due to their biofilm lifestyle. The ability of C. albicans to invade human tissues is due to its filamentation. Therefore, inhibition of biofilms and filamentation of the yeast are high value targets to develop the next-generation antifungals. Curcumin (CU) is a natural polyphenol with excellent pharmacological attributes, but limitations such as poor solubility, acid, and enzyme tolerance have impeded its practical utility. Sophorolipids (SL) are biologically-derived surfactants that serve as efficient carriers of hydrophobic molecules such as curcumin into biofilms. Here, we synthesised a curcumin-sophorolipid nanocomplex (CUSL), and comprehensively evaluated its effects on C. albicans biofilms and filamentation. Our results demonstrated that sub-inhibitory concentration of CUSL (9.37 µg/mL) significantly inhibited fungal adhesion to substrates, and subsequent biofilm development, maturation, and filamentation. This effect was associated with significant downregulation of a select group of biofilm, adhesins, and hyphal regulatory genes. In conclusion, the curcumin-sophorolipid nanocomplex is a potent inhibitor of the two major virulence attributes of C. albicans, biofilm formation and filamentation, thus highlighting its promise as a putative anti-fungal agent with biofilm penetrative potential.

Debris extrusion during root canal preparation with nickel-titanium instruments using liquid and gel formulations of sodium hypochlorite in vitro.

This study compared the amount of apically extruded debris during root canal preparation with three single-file systems using liquid and gel-based formulations of sodium hypochlorite (NaOCl) or distilled water. Seventy-two single-canalled roots were divided into three groups: HyFlex EDM (Coltene-Whaledent); Reciproc Blue (VDW); and F-One Blue (Shanghai Fanta) and then divided into three subgroups: NaOCl liquid (Imicrly), NaOCl gel (Cerkamed Medical) and distilled water. The amount of extruded debris was calculated by determining the dry weight of the debris collected. Data were analysed using Kruskal-Wallis test with Bonferroni correction. Debris extrusion occurred in all subgroups. Both the instrument and the irrigant had an impact. The F-One Blue tended to extrude the least debris, though no significant difference was observed in the pairwise comparisons between instruments. NaOCl liquid resulted in significantly more extruded debris than NaOCl gel or distilled water. The results lead us to conclude that the NaOCl gel reduced debris extrusion compared to NaOCl liquid.

Oral health-related quality of life (OHRQoL) before and after endodontic treatment: a systematic review.

OBJECTIVES: This systematic review was undertaken to determine the oral health-related quality of life (OHRQoL) before and after endodontic treatment. MATERIALS AND METHODS: Based on the PRISMA guidelines, electronic databases (n = 7) were searched and from 1038 citations, 16 papers were included in this review. Information on study design, sample size, intervention/treatment modality, methods of assessing OHRQoL, and the key findings were extracted and analyzed. RESULTS: Among the 16 studies, 3 were cross-sectional surveys, 9 were longitudinal studies, and 4 were randomized clinical trials. The cross-sectional studies reported improvements in OHRQoL following root canal treatment. Comparative longitudinal studies did not identify a significant association between improvements in OHRQoL and the method of root canal instrumentation or number of instruments used. Clinical trials found that improvements in OHRQoL were significantly associated with instrumentation technique, surgical-incision approach, and the application of platelet-concentrate during surgery. Several methods of assessing OHRQoL were employed with the most common being the Oral Health Impact Profile (OHIP), albeit using different versions. CONCLUSIONS: The results of this systematic review indicate that the QoL of patients improved after endodontic treatment. Nevertheless, these results are limited to patients who seek endodontic treatment and cannot be generalized. The lack of well-designed observational studies with standardized assessment approaches, coupled with heterogeneity of study design and interventions, precluded quantitative synthesis. CLINICAL RELEVANCE: Pragmatic clinical trials are more meaningful to understand patient-centered outcomes of treatment. This review shows that endodontic treatment does improve the QoL. However, future studies should use standardized tools and data reporting, which are critical to make meta-analyses possible.

Enterococcus faecalis immunoregulates osteoclastogenesis of macrophages.

Persistent apical periodontitis (PAP) is characterized by refractory inflammation and progressive bone destruction. Enterococcus faecalis infection is considered an important etiological factor for the development of PAP, although the exact mechanisms remain unknown. This study aimed at investigating the role of E. faecalis in cell proliferation, inflammatory reactions and osteoclast differentiation of macrophages using an in vitro infection model of osteoclast precursor RAW264.7 cells. A cell viability assay of cultured RAW264.7 cells exposed to live E. faecalis at a multiplicity of infection of 100 for 2h, indicated that the infection exhibited no cytotoxic effect. Transmission electron microscopy images revealed no apoptotic changes but a rise of metabolic activity and phagocytic features in the infected RAW264.7 cells. Confocal laser scanning microscopic and flow cytometric analysis indicated that the phagocytosis of RAW264.7 cells was activated by E. faecalis infection. Furthermore, quantitative real-time PCR assays demonstrated that the expression of inflammatory cytokines was remarkably elevated in infected RAW264.7 cells. Differentiation of infected RAW264.7 cells into osteoclasts was remarkably attenuated, and expression of osteoclast marker genes as well as fusogenic genes significantly dropped. In summary, E. faecalis appears to attenuate osteoclastic differentiation of RAW264.7 precursor cells, rather stimulates them to function as macrophages.

Evolution of Nickel-titanium Alloys in Endodontics.

To improve clinical use of nickel-titanium (NiTi) endodontic rotary instruments by better understanding the alloys that compose them. A large number of engine-driven NiTi shaping instruments already exists on the market and newer generations are being introduced regularly. While emphasis is being put on design and technique, manufacturers are more discreet about alloy characteristics that dictate instrument behavior. Along with design and technique, alloy characteristics of endodontic instruments is one of the main variables affecting clinical performance. Modification in NiTi alloys is numerous and may yield improvements, but also drawbacks. Martensitic instruments seem to display better cyclic fatigue properties at the expense of surface hardness, prompting the need for surface treatments. On the contrary, such surface treatments may improve cutting efficiency but are detrimental to the gain in cyclic fatigue resistance. Although the design of the instrument is vital, it should in no way cloud the importance of the properties of the alloy and how they influence the clinical behavior of NiTi instruments. CLINICAL SIGNIFICANCE: Dentists are mostly clinicians rather than engineers. With the advances in instrumentation design and alloys, they have an obligation to deal more intimately with engineering consideration to not only take advantage of their possibilities but also acknowledge their limitations.

Three-dimensional Quantitative Porosity Characterization of Syringe- versus Hand-mixed Set Epoxy Resin Root Canal Sealer

The aim of the present study was to compare the porosity characteristics of AH Plus Jet(tm) syringe-mix and the conventional hand-mixed AH Plus root canal sealers by three-dimensional quantitative high-resolution micro-computed tomography (micro-CT). Seven test specimens were prepared from each tested sealer by a single operator following the manufacturer's instructions and poured into pre-lubricated plastic split-ring moulds. Set sealer test specimens were scanned using a micro-CT device and the shadow images were reconstructed into cross-sectional slices. The evaluated parameters were (i) total pore count, (ii) total pore volume and mean pore volume, (iii) total porosity (% of pore volume in relation to total sealer volume) and (iv) mean pore distance to the sealer lateral external surface. In both groups, most pores were localized within the external sealer perimeter (0.05 mm from the external surface). Hand-mixed AH Plus specimens showed statistically significant higher mean total pore count, total pore volume and total porosity (p=0.001) than the syringe-mixed specimens. However, mean pore sizes in AH Plus syringe-mixed specimens were significantly higher (p=0.046) than the AH Plus hand-mixed counterparts. Hand-mixed AH Plus was associated with higher total mean pore count, volume and total porosity compared to syringe mixed AH Plus.

Resumo O objetivo do presente estudo foi comparar a porosidade do AH Plus Jet(tm) dotado de misturador automático com o AH Plus convencional manipulado a mão a partir de um método quantitativo de microtomografia computadorizada (micro-CT). Para cada cimento, sete espécimes foram preparados por um único operador, seguindo as instruções do fabricante, e inseridas em anéis de plástico. Após o tempo de presa, os cimentos foram escaneados utilizando o micro-CT e as imagens foram reconstruídas. Os parâmetros avaliados foram (i) contagem total de poros, (ii) volume total de poros e média dos volumes dos poros, (iii) porosidade total (% de volume de poros em relação ao volume total do cimento) e (iv) distância média dos poros em relação ao perímetro externo (0,05 mm da superfície externa). O AH Plus manipulado a mão apresentou maior número de poros, maior volume total de poros e porosidade total (p=0,001) comparado com o AH Plus com misturador. No entanto, a média de tamanho dos poros foi estatisticamente superior no AH Plus com misturador quando comparado com o AH Plus manipulado a mão (p=0,046). O AH Plus manipulado a mão foi associado com uma maior média de poros, volume e porosidade quando comparado com o AH Plus com misturador.

Maxillary first molar with 8 root canals detected by CBCT scanning: a case report.

Maxillary molars are prone to exhibit some of the most complex root canal configurations in endodontics. These complexities can result in diagnostic dilemmas, as well as management challenges. This case report illustrates how a cone beam computed tomography (CBCT) scan confirmed an unusual maxillary first molar with 3 root canals each in the mesiobuccal and distobuccal roots and 2 canals in the palatal root. This article illustrates how CBCT scanning and a dental operating microscope can facilitate a better understanding of complex root canal anatomies, ultimately allowing the dentist to clean, shape, and obturate root canal systems more efficiently.

Bacteriology of deep carious lesions underneath amalgam restorations with different pulp-capping materials - an in vivo analysis

Microorganisms remaining in dentin following cavity preparation may induce pulp damage, requiring the use of pulp-capping agents with antimicrobial activity underneath permanent restorations. OBJECTIVE: The aims of this study were to analyze the bacteriological status of carious dentin and to assess the efficacy of different base underneath silver amalgam restorations. MATERIAL AND METHODS: This study was conducted on 50 patients aged 13 to 30 years. Sterile swabs were used to take samples after cavity preparation, which was assessed by microbiological culture to identify the microorganisms present. Following this, cavities were restored with silver amalgam, using one of the materials being investigated, as the base: calcium hydroxide (Group II), polyantibiotic paste (Group III), a novel light-cured fluoride-releasing hydroxyapatite-based liner (Group IV) and mineral trioxide aggregate - MTA (Group V). In Group I, the cavities were restored with silver amalgam, without any base. After 3 months, the amalgam was removed and samples taken again and analyzed for the microbial flora. RESULTS: Lactobacilli were the most commonly isolated microorganisms in the samples of carious dentin. Groups IV and V showed negative culture in the 3-month samples. There was no statistically significant difference between Groups I, II and III. There was no significant difference between Groups IV and V (p>0.05). Both Groups IV and V showed significantly better results when compared to Groups I, II and III (p<0.05). CONCLUSIONS: The hydroxyapatite-based liner and MTA performed significantly better in terms of antibacterial activity than the other materials.

Can traumatic occlusion cause endodontic problems? A case report.

Radicular cysts are commonly found odontogenic cysts in the jaws. The lesion is diagnosed mainly in young patients during the second decade of life. In the majority of cases, it is asymptomatic. This paper reports a rare case in which traumatic occlusion was identified as the etiology of a radicular cyst. Endodontic treatment was performed and the traumatic occlusion also was corrected. A six-month follow-up appointment found good healing of the periapical region.

Duration-dependent susceptibility of endodontic pathogens to calcium hydroxide and chlorhexidene gel used as intracanal medicament: an in vitro evaluation.

The aim of this study was to evaluate the effective duration of antimicrobial activity of a calcium hydroxide-based medicament (Apex Cal) and 2% chlorhexidene gluconate gel against selected endodontic pathogens (Enterococcus faecalis, Candida albicans, Porphyromonas gingivalis, and Prevotella intermedia). The agar diffusion test was used to determine the antimicrobial activity. Chlorhexidene gluconate gel showed the largest inhibitory zones. The antimicrobial action of both medicaments decreased significantly with time, with calcium hydroxide showing no antimicrobial action after 72 hours. In conclusion, 2% chlorhexidene gel showed better antimicrobial activity than calcium hydroxide, and the effective antimicrobial action of both medicaments decreased after 48 hours.