Mast cells (MCs) were first described by Paul Ehrlich 1 in his doctoral thesis. MCs have long been implicated in the pathogenesis of allergic reactions and certain protective responses to parasites. As most tumors contain inflammatory cell infiltrates, which often include plentiful MCs, the question as to the possible contribution of MCs to tumor development has progressively been emerging. In this chapter, the specific involvement of MCs in tumor biology and tumor fate will be considered, with particular emphasis on the capacity of these cells to stimulate tumor growth by promoting angiogenesis and lymphangiogenesis. Data from experimental carcinogenesis and from different tumor settings in human pathology will be summarized. Information to be presented will suggest that MCs may serve as a novel therapeutic target for cancer treatment.

Mast cells, angiogenesis and cancer.

Martos J, Bassotto APS, Gonzalez-Rodriguez MP, Ferrer-Luque CM Dissolving efficacy of eucalyptus and orange oil, xylol and chloroform solvents on different root canal sealers International Endodontic Journal, 44, 1024–1028, 2011

Abstract
Aim  To evaluate the solubility of five root canal sealers in orange oil, eucalyptol, xylol and chloroform solvents

Methodology  The solubility of RoekoSeal, Sealer 26, Epiphany, Endomethasone and EZ-Fill sealers was assessed in orange oil, eucalyptol, xylol, chloroform and distilled water Seventy-five samples of root canal sealers were prepared and then divided into five groups for immersion in solvent for 2, 5 or 10 min The means of loss weight were determined for each material in each solvent at all immersion periods, and the values were compared by factorial analysis of variance (anova) and SNK multiple comparisons

Results  In the orange and eucalyptus oil groups, there was no significant difference among RoekoSeal, Sealer26, Epiphany and EZ-Fill at the three immersion periods (P > 005) With xylol, no significant differences were found at 5 and 10 min (P > 005) for each root sealer Orange and eucalyptus oil solvents were as effective as chloroform at 2 min in dissolving all the root sealers

Conclusions  Xylol was the most effective solvent followed by the chloroform and the essential oils (eucalyptol and orange oil) Orange oil behaved in a similar way to eucalyptus oil

Dissolving efficacy of eucalyptus and orange oil, xylol and chloroform solvents on different root canal sealers

The aim of this study was to evaluate the effectiveness of 3 solvents (eucalyptol, orange oil, and xylol) on 2 types of gutta-percha (conventional and thermoplastic) and Resilon. Specimens (10 mm diameter x 1 mm thick; n=7 per condition) were prepared and maintained at 37 degrees C for 48 h. Each specimen was weighed on a precision scale every 24 h until its mass was stable, at which time the initial mass was determined. Specimens (n=7) were then immersed in the solvent solutions and, after 48 h at 37 degrees C, they were reweighed at 24- h intervals, until stabilization (final mass). The difference between the final and the initial mass determined the solvent capacity of each solvent. Data were subjected to analysis of variance and Tukey's test at 5% significance level. The results demonstrated that xylol was the most effective, especially on conventional gutta-percha and Resilon (p<0.05). Eucalyptol and orange oil were more effective on thermoplastic gutta-percha than the other materials (p<0.05). It was concluded that all evaluated substances presented solvent action, but xylol was the most effective on both gutta-percha or Resilon.

/pdf/solvent-capacity-of-different-substances-on-gutta-percha-and-3s3l3qaf4g.pdf

Solvent capacity of different substances on gutta-percha and Resilon

Introduction: The purpose of this in vitro study was to evaluate three common gutta-percha solvents’ effectiveness in dissolving three different types of root canal sealers. Materials and Methods: The solubility of three different root canal sealers (AH Plus, Apexit Plus and Endoflas FS) was assessed in xylene, refined orange oil, tetrachloroethylene and distilled water (control). One-hundred twenty samples of root canal sealers were prepared and then divided into three equal groups ( n =40). Each group was further divided into four equal subgroups ( n =10) for immersion in the respective solvents for a 10 minute immersion period. The mean amount of weight loss was determined for each material in each solvent during the specified immersion period, and the values were subjected to statistical analysis. Results: Xylene exhibited the greatest dissolving efficacy for AH Plus, followed by refined orange oil and tetrachloroethylene. Xylene was also able to dissolve the greatest amount of Apexit Plus, followed by refined orange oil and tetrachloroethylene which were equally effective in dissolving Apexit Plus. For Endoflas FS, maximum dissolving efficacy was seen with tetrachloroethylene followed by refined orange oil and xylene. Conclusion : The results showed that xylene, refined orange oil and tetrachloroethylene can be used for the removal of AH Plus, Apexit plus and Endoflas FS sealers during endodontic retreatment. Further clinical investigations are needed to evaluate the efficacy of these solvents on different sealers.

/pdf/the-dissolving-ability-of-different-organic-solvents-on-3b1glq72qw.pdf

The dissolving ability of different organic solvents on three different root canal sealers: in vitro study.

Although mast cells (MCs) have been discovered over 130 years ago, their function was almost exclusively linked to allergic affections At the time being, it is well known that MCs possess a great variety of roles, in both physiologic and pathologic conditions In the oral tissues, MCs release different proinflammatory cytokines, tumor necrosis factor alpha (TNF-α), that promote leukocyte infiltration in various inflammatory states of the oral cavity These cells play a key role in the inflammatory process and, as a consequence, their number changes in different pathologic conditions of the oral cavity, like gingivitis, periodontitis, and so on MCs also represent a rich source of proteases, especially of mast cell tryptase and chymase, which directly degrade the extracellular matrix through their proteolytic activity and thus indirectly stimulate angiogenesis and facilitate invasion and metastasis It may be stated that mast cells could have an impact on primary tumor development, progression, and metastases in oral squamous cell carcinoma By understanding the role of mast cells in the pathogenesis of different inflammatory and tumor diseases of the oral cavity, these cells may become therapeutic targets that could possibly improve the prognosis and survival of these patients

/pdf/mast-cells-key-players-in-the-shadow-in-oral-inflammation-5g7f0sbhm5.pdf

Mast Cells: Key Players in the Shadow in Oral Inflammation and in Squamous Cell Carcinoma of the Oral Cavity.

The aim of this study was to evaluate the solubility of gutta-percha in four organic solvents used in endodontics. The solubility of gutta-percha (Dentsply) was assessed in xylol, orange oil, eucalyptol, chloroform and distilled water. A hundred and fifty samples of gutta-percha were prepared using a standardized stainless steel mould and divided into five groups for immersion in the different solvents tested and in distilled water (control group) for 2, 5 and 10 minutes. The means of gutta-percha dissolution in the solvents were obtained by the difference between the pre-immersion original weight and the post-immersion weight in a digital analytical scale (Gehaka-AG2000). Data were statistically analyzed by Analysis of Variance (ANOVA) and multiple comparisons with Scheffes test (p<0.05). The best solvency capacity was obtained with xylol. Chloroform, orange oil and eucalyptol presented similar results, and distilled water did not promote alterations in the gutta-percha.

/pdf/dissolving-efficacy-of-some-organic-solvents-on-gutta-percha-vgrojx9fvr.pdf

Dissolving efficacy of some organic solvents on gutta-percha.

Previous studies have shown that the number of mast cells is increased in ultraviolet (UV) irradiated skin and in neoplasias. Actinic cheilitis (AC) is a lesion caused by excessive exposure to sunlight that can transform into lip squamous cell carcinoma. The aim of this study was to compare the number of mast cells in 4 groups: NOM = normal oral mucosa (n=6); MDAC = mild dysplasia in actinic cheilitis (n=13); SDAC = severe dysplasia in actinic cheilitis (n=13); and LSCC = lip squamous cell carcinoma (n=15). The sections were stained by histochemical technique of blue toluidine and visual counting was performed with the aid of a reticulum coupled to the microscope ocular. A calibrated observer performed the count in 5 fields by case at ×400 magnification. The largest mean number of mast cells per group was observed in LSCC (40.1), followed by MDAC (30.5), SDAC (28.6) and NOM (12.2). There were significant differences between NOM and MDAC (p<0.05) and between NOM and LSCC (p<0.05). The increased density of mast cells observed in AC and in LSCC compared to NOM suggests a role for the mast cells in the development of these lesions.

/pdf/comparative-analysis-of-the-mast-cell-density-in-normal-oral-46tmccawbi.pdf

Comparative analysis of the mast cell density in normal oral mucosa, actinic cheilitis and lip squamous cell carcinoma

Endodontic re-treatment is a conservative clinical conduct in comparison with more radical procedures. Removal of endodontic filling material from the root canal is an essential requirement for retreatment. The aim of this study is to review the literature about the use of solvents in endodontic retreatment

Use of organic solvents in endodontics: a review

USE OF ORGANIC SOLVENTS IN ENDODONTICS: A REVIEW Utilização de solventes orgânicos em endodontia: revisão

The aim of this study was to evaluate the solubility of gutta-percha in four organic solvents used in endodontics. The solubility of gutta-percha (Dentsply) was as- sessed in xylol, orange oil, eucalyptol, chloroform and distilled water. A hundred and fifty samples of gutta-percha were prepared using a standardized stainless steel mould and divided into five groups for immersion in the different solvents tested and in distilled wa - ter (control group) for 2, 5 and 10 minutes. The means of gutta-percha dissolution in the solvents were obtained by the difference between the pre-immersion original weight and the post-immersion weight in a digital analytical scale (Gehaka - AG2000). Data were statistically analyzed by Analysis of Variance (ANOVA) and multiple comparisons with Scheffe's test (p < 0.05). The best solvency capacity was obtained with xylol. Chloroform, orange oil and eucalyptol presented similar results, and distilled water did not promote alterations in the gutta-percha. Descriptors: Endodontics; Retreatment; Solubility; Gutta-percha; Solvents.

Julia Elis Johann

Papers

Dissolving efficacy of some organic solvents on gutta-percha.

Comparative analysis of the mast cell density in normal oral mucosa, actinic cheilitis and lip squamous cell carcinoma

Use of organic solvents in endodontics: a review

USE OF ORGANIC SOLVENTS IN ENDODONTICS: A REVIEW Utilização de solventes orgânicos em endodontia: revisão

Dissolving efficacy of some organic solvents on gutta-percha Eficácia dissolvente de alguns solventes orgânicos sobre a guta-percha