Análise morfológica de operárias de Atta sexdens rubropilosa tratadas com thiamethoxam

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Características dos espermatozóides em espécies de Leptodactylus (Anura, Leptodactylidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Distribution of constitutive heterochromatin in species of triatomines with fragmentation of sex chromosomes X

Cytogenetic analyses of triatomines are considered to be important taxonomic tools. Thus, we analyzed the pattern of constitutive heterochromatin in 7 species of triatomine with fragmentation of the sex chromosome X, focusing on the cytotaxonomy of these triatomines. The species analyzed included Triatoma vitticeps, Triatoma melanocephala, Triatoma tibiamaculata, Triatoma protracta, Meccus pallidipennis, Panstrongylus megistus, and Panstrongylus lignarius. The seminiferous tubules of the adult males were subjected to C-banding. P. megistus and P. lignarius showed differences in chromosome number and disposition of constitutive heterochromatin, as only P. lignarius showed C-blocks in autosomes. C-banding can differentiate these species, since one of the sex chromosome (X) is heterochromatic in T. vitticeps. T. protracta showed C-blocks in both ends of all autosomes, T. tibiamaculata showed terminal C-dots in some autosomal pairs and M. pallidipennis did not show constitutive heterochromatin in autosomes. Thus, we confirmed the heterochromatic pattern of 7 species of insects and emphasized the importance of cytogenetic techniques for C-banding for taxonomy studies of the triatomines, which are important vectors of Chagas disease.

Review: Malpighian Tubule, an essential organ for insects

We did an overhaul on morphophysiology characteristics, cryptonephric system and secondary specializations in the Malpighian tubules of the class Insecta. This review grouped the most important information about this important organ that has different functions essential for insects.

Cárie oculta extensa: relato de caso clínico

The pattern of caries lesions has been modified over decades. If the presence or absence of a caries lesion is based upon only a visual examination, its diagnosis might become underestimated since dentinal lesions underneath non cavitated or minimally demineralized enamel is highly frequent in dental clinics. The aim of this paper is to report a clinical case of a child with an upper molar with questionable occlusal aspect, presenting asymptomatic pulpal hyperplasia on the distolingual pit. Periapical radiographic examination was essential for diagnosing hidden caries and elaborating the treatment plan. As part of the approach, removal of the decayed tissue and pulpotomy with calcium hydroxide were performed. The association of an accurate visual examination to an adequate oral radiographyis is extremely important in cases which the presence of hidden caries is doubtful. As a result, an early diagnosis and the reduction of more invasive interventions related to the oral health care of pediatric patients can be achieved as well.

Relação entre materiais dentários e o complexo dentino-pulpar

Despite the strong valorization of the esthetics and its relationship with restorative materials, the biological principles of any clinical procedure are extremely important to maintain the vitality of the dentin-pulp complex. Dentin and pulp tissue are susceptible to different kinds of irritants such as toxins from microorganisms, traumatic procedures of cavity preparation, as well as toxic components released by restorative materials applied in non recommended clinical situations. Initially, the pulp responds to irritation by starting an inflammatory reaction which involves outward movement of dentinal fluid and intratubular deposition of immunoglobulins, upregulation of odontoblast activities, presence of immune cells and their cytokines as well as local expression of neuropeptides and chemokines. After these initial events, the inflammation process can be resolved associated or not to sclerotic dentin formation and reactionary dentin deposition. If high intensity offensive stimuli are applied to the dentin-pulp complex, death of odontoblasts takes place and consequently pulp ageing or even partial necrosis of this tissue may occurs. Thereby, clinicians need to be aware about the physiological and pathological features of the dentin-pulp complex as well as the possible biological consequences of different clinical procedures. In this way, the dentists should be able to carry out minimally aggressive operative techniques and to select the more appropriate restorative materials for each specific clinical situation in order to obtain excellent clinical results associated to the maintenance of pulp vitality.

Citotoxicidade transamelodentinária de uma fita clareadora com 10% de peróxido de hidrogênio sobre células de linhagem odontoblástica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clareamento para dentes despolpados: revisão de literatura e considerações

The esthetics of the teeth is not a privilege of our days, because concerns in that effect have been reported since 1860. Faced with an endodontically treated tooth that presents any type of color change, professionals can use intracoronary bleaching, which is more conservative attempt to restore the normal color of teeth. Bleaching aims to remove pigments by oxidizing agents and for that, various techniques were developed. Among the risks of tooth whitening the external resorption is the most severe, which occurs when the whitening penetrates through the dentin tubules to the periodontal ligament and initiates an inflammatory response. To prevent external resorption is required to place an intracoronal bleaching barrier. It is important to know the time between the bleaching treatment for restoring procedure for getting a good sealing to prevent microleakage. This study aims to review the literature about the different types of bleaching agents and their risks.

Hipersensibilidade dentinária cervical: em busca de um tratamento eficaz

The knowledge of the etiology of any disease or condition is paramount to a safe and effective treatment. This literature review aims to show some options to treat dentine hypersensitivity (HSDC). The loss of cervical enamel and cementum exposure of tubules leads to a painful condition and patient discomfort, called HSDC. This loss of tooth structure occurs due to formation of cervical lesions in cases of gingival recession, abrasion, erosion, or abfraction by the association of two or more factors. Some treatments are not effective, but there are effective therapies, such as: application of ferric oxalate, potassium oxalate, potassium nitrate, fluoride varnish, solutions of calcium phosphate, adhesives and Bonding procedures. Therefore, the identification and removal of etiological factors is essential to successful treatment of HSDC normally associated to tubules obliterate and consequent reduction of fluid motion within the dentin.

Comparative analysis of three rotary instruments used for coronal pre-enlargement in radicular dentin thickness and root canal area of mandibular molars

Purpose: The purpose of this study was to evaluate the increase of the cervical area and dentin thickness in mesial and distal walls of the mesial canals from mandibular molars after the use of LA Axxess (LA), CP Drill (CP) and Gates-Glidden (GG) rotary instruments. Material and Methods: Sixty root canals from thirty mandibular first molar were sectioned 3 mm below the cement-enamel junction, divided in 3 groups (n = 20 root canals, each) according to rotary instrument used, and the cervical images were captured before and after pre-enlargement instrumentation. The increase of the instrumented cervical area (mm2) and the dentin removal thickness (mm), at mesial and distal walls were calculated using Image tools software, by comparison of images. Data were analyzed by ANOVA and Tukey tests (p=0.05). Results: All rotary instruments promoted thickness reduction in dentin walls. In mesial wall, all rotary instruments promoted similar thickness reduction of dentinal wall and did not differ from each other (p>0.05). In distal wall, LA Axxess instrument promoted higher dentin thickness reduction than other groups (p<0.05). The three rotary instruments promoted different increase at the instrumented cervical area (p<0.05), LA promoted the highest increase area and GG and CP presented similar results. Conclusion: LA 20/0.06 promoted the highest thickness reduction in distal wall and increase of cervical area of root canal. On the other hand, CP was the safest instrument, with lower dentin removal of distal wall and similar increased area to GG.

Effect of Er:YAG laser and diamond drill on hybrid layer morphology obtained with self-etch adhesive: analysis by SEM and confocal laser scanning microscopy (CLSM)

This study aimed to evaluate the effect of Er:YAG (L) and diamond drills (DD) on: 1) the microshear bond strength (MPa); 2) the adhesive interface of two-step (TS) – Adper Scotchbond Multipurpose and one-step (OS) adhesives – Adper EasyOne, both from 3M ESPE. Material and methods: According to the preparation condition and adhesives, the samples were divided into four groups: DD_TS (control); DD_OS; L_TS and L_OS. 60 bovine incisors were randomly divided into experimental and groups: 40 for microshear bond strength (n = 10) and 20 for the adhesive interface morphology [6 to measure the thickness of the hybrid layer (HL) and length of tags (t) by CLSM (n = 3); 12 to the adhesive interface morphology by SEM (n = 3) and 2 to illustrate the effect of the instruments on dentine by SEM (n = 1)]. To conduct the microshear bond strength test, four cylinders (0.7 mm in diameter and 1 mm in height with area of adhesion of 0.38 mm) were constructed with resin composite (Filtek Z350 XT – 3M ESPE) on each dentin surface treated by either L or DD and after adhesives application. Microshear bond strength was performed in universal testing machine (EMIC 2000) with load cell of 500 kgf and a crosshead speed of 0.5 mm / min. Adhesive interface was characterized by thickness of hybrid layer (HL) and length of tags (t) in nm, with the aid of UTHSCSA ImageTool software. Results: Microshear bond strength values were: L_TS 34.10 ± 19.07, DD_TS 24.26 ± 9.35, L_OS 33.18 ± 12.46, DD_OS 21.24 ± 13.96. Two-way ANOVA resulted in statistically significant differences only for instruments (p = 0.047). Mann-Whitney identified the instruments which determined significant differences for HL thickness and tag length (t). Concerning to the adhesive types, these differences were only observed for (t). Conclusion: It can be concluded that 1) laser Er:YAG results in higher microshear bond strength values regardless of the adhesive system (TS and OS); 2) the tags did not significant affect the microshear bond strength; 3) the adhesive interface was affected by both the instruments for cavity preparation and the type of adhesive system used.

Recobrimento radicular para o tratamento de hipersensibilidade dentinária cervical persistente

Gingival recession has a high prevalence in the population. This alteration may promote several complications such as cervical dentinal hypersensitivity (HSDC), carious and non-carious cervical lesions, and cosmetic changes due to the increase of the clinical crown length. To treat HSDC there are several therapeutic possibilities that should aim to eliminate pain after external stimulus. Treatment of this alteration can be performed by a conventional or invasive procedure, depending on the clinical condition and patients' desires. In situations where aesthetics is not the main complaint and HSDC persists even after conservative procedures, it is possible to indicate a procedure to achieve root coverage in Miller's Class I and II recessions. The aim of this paper is to report a case where the HSDC was not eliminated by conventional methods, which was resolved only after performing a minimally invasive surgery that promoted total root coverage.

In vitro evaluation of Biosilicate® dissolution on dentin surface: a SEM analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Os efeitos da alta temperatura e do myleran (busulfan) na espermatogênese de Devario aequipinnatus (teleostei, cyprinidae)

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Evaluation of testicular tissue of adult rats treated with cisplatin incorporated into the liposome

Cisplatin (CPL) is one of the most widely used and effective chemotherapeutic agents for the treatment of several human malignancies. However, it causes serious side effects, especially on reproduction. In order to reduce the undesirable effects caused by many drugs, liposomes have been used as a good system for drug delivery. The aim of this study was to investigate, for the first time, the effects of CPL incorporated into the dipalmitoyl phosphatidylcholine liposome (DPPC) on the testicular tissue of adult Wistar rats. The animals (n = 20) were distributed into four experimental groups: (a) control (distillated water); (b) liposome (DPPC, 1 mL), (c) cisplatin incorporated into liposome (CPL/DPPC), and (d) CPL (8 mg/kg body weight). The animals received a single intraperitoneal injection and were killed 10 days after each treatment for histopathological analysis of testes. The results showed that the testicular histomorphometric parameters in rats of DPPC and CPL/DPPC groups were similar to those of the control group. Meanwhile, rats of the CPL-treated group showed a variety of morphological alterations, including atrophy of seminiferous tubules and presence of multinucleated cells in the germinal epithelium. The incorporation of CPL into the liposome had no influence on the testicular weight or any other stereological parameters, but it was beneficial in maintaining the body weight of the animals. In conclusion, the liposome suppressed the cytotoxic effects caused by cisplatin in the testes of rats, suggesting a possible use in chemotherapy against cancer to reduce the side effects seen on reproduction.