Palisaded encapsulated neuroma in tongue - A commonly misdiagnosed peripheral nerve sheath tumor.

Palisaded encapsulated (solitary circumscribed) neuromas are benign neural tumors, rarely found in oral mucosa. This case reports a 24-year-old man that presented a unique soft nodule at the left side of the tongue. An excisional biopsy was performed under local anesthesia and histopathological examination of the surgical specimen revealed a well circumscribed mass composed of spindled Schwann cells, often aligned and fasciculated, forming occasional nodules embedded in a fibrous stroma. Histopathological analysis showed the presence of positive cells for S-100, EMA, CD57, and collagen IV. Based on clinical and microscopical features, the diagnosis established was of palisaded encapsulated neuroma. This case report aims to discuss the differential diagnosis among palisaded encapsulated neuroma and the other neural tumors that affect the oral mucosa.

Palisaded encapsulated neuroma in tongue: a commonly misdiagnosed peripheral nerve sheath tumor

Palisaded encapsulated (solitary circumscribed) neuromas are benign neural tumors, rarely found in oral mucosa. This case reports a 24-year-old man that presented a unique soft nodule at the left side of the tongue. An excisional biopsy was performed under local anesthesia and histopathological examination of the surgical specimen revealed a well circumscribed mass composed of spindled Schwann cells, often aligned and fasciculated, forming occasional nodules embedded in a fibrous stroma. Histopathological analysis showed the presence of positive cells for S-100, EMA, CD57, and collagen IV. Based on clinical and microscopical features, the diagnosis established was of palisaded encapsulated neuroma. This case report aims to discuss the differential diagnosis among palisaded encapsulated neuroma and the other neural tumors that affect the oral mucosa(AU).

Efeito potencial de uma goma de mascar experimental com cimento de ionômero de vidro em sua formulação / Evaluation of the potential effect of a chewing gum containing experimental Glass Ionomer Cement

O objetivo desse estudo é o de avaliar o potencial efeito de uma goma de mascar (chiclete) experimental, que contém Cimento de Ionômero de Vidro (CIV), na prevenção da doença cárie. Metodologia: seleção de quinze crianças/adolescentes, com idade entre 06 e 19 anos, que necessitam da adoção de medidas de tratamento e prevenção à cárie. Após expresso Termo de Consentimento Livre e Esclarecido em participar, os sujeitos da pesquisa foram divididos aleatoriamente em três grupos distintos: Grupo A: goma de mascar experimental; Grupo B: goma de mascar neutra (placebo); Grupo C: selamentos convencionais não invasivos. Para a avaliação do potencial efeito preventivo à cárie foram realizadas repetidas avaliações clínicas e coleta de saliva total estimulada, para análises de pH, fluxo, capacidade tampão e concentração de flúor. Inspeções nas superfícies oclusais de molares e/ou prémolares foram realizadas por meio de minucioso exame clínico, documentação fotográfica com luz convencional, com luz fluorescente (Quantitative Light Fluorescence) e microscopia eletrônica de varredura, por meio de réplicas com silicona de adição, a fim de se constatar a presença de CIV nas áreas de cicatrículas e fissuras. Adicionalmente, foram aplicados questionários de perguntas e respostas aos responsáveis e aos próprios sujeitos da pesquisa, com objetivo de avaliar a aceitação da goma de mascar como veículo de finalidade terapêutica. Todas as análises foram feitas por pesquisadores independentes (exame cego). Resultados: as avaliações clínicas e fotográficas não demonstraram qualquer tipo de selamento das cicatrículas e fissuras de molares e/ou pré-molares bem como a análise de réplicas em microscopia eletrônica de varredura. No período avaliado, não foram identificadas áreas de remineralização com o uso de luz fluorescente. Os resultados laboratoriais demonstraram sinais favoráveis ao processo de remineralização dos tecidos dentários. Teste estatístico não paramétrico...

The aim of this study is to evaluate the potential effect of a chewing gum containing experimental Glass Ionomer Cement (GIC) in preventing caries. Methodology: fifteen children / adolescents aged between 06 and 19 years old in need of treatment and prevention of dental caries were selected. After formal agreement to take part in the research, the participants were divided randomly into three groups: Group A: experimental gum; Group B: neutral gum (placebo); Group C: conventional noninvasive sealing. To assess the potential preventive effect on caries, repeated clinical assessments were carried out, as well as a collection of stimulated saliva for analysis of pH, flow, buffering capacity and fluoride concentration. In order to verify the presence of GIC in the areas of pits and fissures, inspections on the occlusal surfaces of molars and / or premolars were conduced by thorough clinical examination, photographic documentation with conventional light, fluorescent light (Quantitative Light Fluorescence) and scanning electron microscopy, using replicas with addition silicone. Additionally, volunteers and researchs staff were submitted to extensive questionnaires, aiming to evaluate the acceptance of chewing gum as a vehicle for therapeutic purposes. All analyses were conducted by independent researchers (blind review). Results: neither clinical and photographic assessments, nor analyses of replicas in scanning electron microscopy showed any kind of sealing pits and fissures of molars and / or premolars. During the specified period, any kind of remineralization was identified with the use of fluorescent light. Nevertheless, laboratory results showed favorable signs in the process of remineralization of dental tissues. Nonparametric statistical test Kruskal-Wallis indicated a significant increase in flow and buffering capacity of saliva after the use of chewing gum, and a significant increase in salivary fluoride...

Miíase oral: relato de caso / Oral myiasis: case report

A miíase oral é uma patologia descrita em países em desenvolvimento que, se não tratada, oferece risco de morte ao paciente. O tratamento consiste na remoção mecânica das larvas, procedimento que é dolorido e constrangedor. Os autores apresentam neste trabalho, o relato de caso clínico de um paciente com 55 anos, indigente, etilista crônico, que apresentou lesão de miíase oral que foi tratado com sucesso pela remoção mecânica das larvas. O uso da invermectina, derivado semi-sintético da família dos macrolídeos, em humanos e seu mecanismo de ação, são também discutidos.

Oral myiasis is a rare pathology and a risk to the patient's life. Conventional treatment is mechanical removal of the larvae (maggots) one by one, which is painful, distressing, and embarrassing both to the patient and to the dentist. The aim of this work is to present a case of a 55-year-old man, indigent, alcohol-dependent, that had oral myiasis treated successfully with mechanical removal of the maggots. The use of ivermectin (a semi-synthetic macrolide agent) in humans, its mechanism of action and indications are also discussed.

Accelerated aging of adhesive-mediated fiber post-resin composite bonds: A modeling approach.

OBJECTIVES: Although fiber posts luted in root canals are not directly exposed to oral fluids, water storage is considered as in vitro accelerated aging test for bonded interfaces. The aim of the study was to evaluate the influence of accelerated water aging on fiber post-resin composite adhesion. METHODS: Forty fiber posts (DT Light Post, RTD) were randomly divided into two main groups, according to the surface treatment performed. Group I: XPBond adhesive (Dentsply Caulk); Group II: sandblasting (Rocatec-Pre, 3M ESPE) and XPBond. Dual-cured resin cement (Calibra, Dentsply Caulk) and flowable composite (X-Flow, Dentsply Caulk) were applied on the posts to produce cylindrical specimens. The bond strength at the interface between post and cement/composite was measured with the microtensile test according to the non-trimming technique. Half of the sticks were tested immediately for bond strength, while in the other half testing was performed after 1 month of water storage at 37 degrees C. Post-cement/composite interfaces were evaluated under SEM prior and after water aging. Statistical analysis was performed using the Kruskal-Wallis ANOVA followed by Dunn's multiple range test (p<0.05). RESULTS: Immediate bond strength was higher on sandblasted posts. After water aging the two post surface treatments resulted comparable in bond strength. Resin cement achieved higher bond strength to fiber posts than flowable composite. Water aging significantly reduced bond strength. CONCLUSIONS: Sandblasting followed by adhesive coating may improve immediate post-resin bond strength in comparison to adhesive alone. However, fiber post-resin bond strength mediated by hydrophilic adhesive tends to decrease after water aging.

The effect of sandblasting on adhesion of a dual-cured resin composite to methacrylic fiber posts: microtensile bond strength and SEM evaluation.

OBJECTIVES: To evaluate the influence of different surface treatments on the microtensile bond strength of a dual-cured resin composite to fiber posts. METHODS: Thirty-two glass methacrylate-based fiber posts (GC Corp.) were used in the study. Posts were divided into two groups, according to the surface pretreatment performed. Group 1: sandblasting (Rocatec-Pre, 3M ESPE). Group 2: no pretreatment. In each of the two groups posts received three types of additional "chair-side" treatments. (1) Silane application (Monobond S, Ivoclar Vivadent); (2) adhesive application (Unifil Core self-etching bond, GC); (3) no treatment was performed. A dual-cured resin composite (Unifil Core, GC) was applied on the posts to produce cylindrical specimens. Specimens were cut to obtain microtensile sticks that were loaded in tension at a cross-head speed of 0.5mm/min until failure. The morphology of the post/composite interface and the post surface morphology were evaluated under SEM. Statistical analysis was performed with two-way ANOVA and Tukey test for post hoc comparisons (p<0.05). RESULTS: Post surface pretreatment did not prove to be a significant factor in post-composite bond strength (p=0.08), whereas "chair-side" treatment modalities and the interaction between pretreatment and treatment showed a significant influence on bond strength (p<0.001). When no "chair-side" treatment was performed, bond strength was significantly higher on sandblasted posts. Additional adhesive application resulted in significantly lower bond strength on sandblasted posts. When no pretreatment was performed, silane application resulted in higher bond strength than adhesive application. CONCLUSIONS: Sandblasting may give an increase in microtensile strength to methacrylate-based glass fiber posts, eliminating the need for additional "chair-side" treatments. Reducing the number of clinical steps could contribute to simplify the clinical procedures.

An in vitro study on the adhesion of quartz fiber posts to radicular dentin.

PURPOSE: To evaluate in vitro the bond strength at the adhesive interface between a quartz fiber post, different adhesive systems, and different composite cements. MATERIALS AND METHODS: Thirty extracted single-rooted teeth were endodontically treated and divided into three groups (n=10). Quartz fiber posts (DT Light-Post) were cemented with the following materials: group I: Prime & Bond NT + Self Cure Activator, and Calibra as luting cement; group II: Prime & Bond NT + Self Cure Activator, and UniFil Core; group III: UniFil Bond in combination with Unifil Core. The specimens were processed for the push-out test to evaluate bond strength at the root dentin-cement-post interface. They were sectioned along the long axis of the post into 1-mm-thick slices. A total of 60 sections was obtained from group I. Group II provided 67 slices, while group III provided 69. Loading was performed at a crosshead speed of 0.5 mm/min until the post segment was dislodged from the root section. RESULTS: There was no statistically significant difference between the three experimental groups. The mean bond strength obtained for group I was 9.81 +/- 5.40 MPa. For group II it was 12.06 +/- 6.25 MPa, and 9.80 +/- 5.01 MPa for group III. CONCLUSION: All the materials tested were similar in terms of providing satisfactory bond strength when used for luting fiber posts. However, Unifil Core may be advantageous since it can also be used as a core buildup material, which simplifies the clinical procedures.

Effect of oxygen inhibition on composite repair strength over time.

The study was aimed at examining whether an oxygen inhibition layer is required for bonding a repairing to a pre-existing composite, and to determine the time required for free radicals within a composite substrate to decay to the extent that the composite repair strength drops significantly. Ten slabs of Gradia Direct Anterior (GC Corp.) were divided into (1) control group: an interfacial oxygen inhibition layer was created by applying and light-curing two layers of bonding resin (D/E Resin, Bisco) to the slabs surface in atmospheric air; (2) experimental group: the absence of an interfacial oxygen inhibition layer was obtained by light-curing the second bonding resin layer in a nitrogen atmosphere. After 1 and 2 h, 1, 14, and 30 days of air storage, a composite repair was layered over the bonding resin. Microtensile bond strengths were measured and statistically analyzed. The curing atmosphere was not a significant factor for bond strength (p = 0.82), and time and curing atmosphere-time interaction were significant (p < 0.001). The 30 day-strengths were the lowest (p < 0.05). An oxygen-inhibited layer is not initially required for bonding to resin composite, and it takes more than 14 days before the bond strength between a pre-existing and a fresh composite drops.

Immediate and 24-hour evaluation of the interfacial strengths of fiber posts.

This study examined the contribution of testing time on the interfacial strengths of fiber posts to radicular dentin. Twenty-five fiber posts were luted to root segments with resin cements and a zinc phosphate cement. Immediately upon setting of the materials, the roots were sectioned into slices and randomly divided into two subgroups, depending on testing time (immediate vs. 24-hours), for push-out test. The results showed an improvement on the interfacial strength after 24 hours of storage. When data were pooled for each cement, the interfacial strengths (MPa) were: Optibond Solo Plus/Nexus: 10.3+/-3.8a; zinc phosphate cement: 10.1+/-2.7a; Multilink: 9.6+/-3.8ab; RelyX Unicem: 7.1+/-4.9bc; AllBond 2/Duolink: 6.7+/-3.5c (groups with same superscript letter were not statistically significant). It is concluded that bond strength can increase during the first 24 hours and that the interfacial strength is predominantly contributed by frictional retention.

Microtensile bond strength and interfacial properties of self-etching and self-adhesive resin cements used to lute composite onlays under different seating forces.

PURPOSE: To evaluate strength and morphology of the interface created on enamel and dentin by Panavia F 2.0 (P, Kuraray), RelyX Unicem (RU, 3M ESPE), and Maxcem (M, Sybron-Kerr), applied under two standardized clinically realistic seating pressures. MATERIALS AND METHODS: Composite overlays (Paradigm MZ100, 3M ESPE) were luted on flat enamel or dentin surfaces of 48 extracted molars. During the initial 5-min self-curing period, a pressure of either 20 or 40 g/mm(2) was maintained on the overlay. Curing was completed by light irradiation from the top of the overlay for 20 s. Microtensile sticks and specimens for SEM observations were obtained from the luted teeth. Bond strength data from enamel and dentin (MPa) were analyzed with separate two-way ANOVAs in order to assess the effect of cement type, luting pressure, and their interactions. Tukey's test was used for post-hoc comparisons (alpha = 0.05). RESULTS: The bond strengths (MPa) to dentin were: P 20 g/mm(2) 7.5 +/- 3.7, 40 g/mm(2) 10.9 +/- 4.5; RU 20 g/mm(2) 6.8 +/- 2.6, 40 g/mm(2) 14.5 +/- 5.3; M 20 g/mm(2) 4.1 +/- 1.8, 40 g/mm(2) 5.2 +/- 1.6. The bond strengths (MPa) to enamel were: P 20 g/mm(2) 25.2 +/- 9.0, 40 g/mm(2) 30.7 +/- 8.6; RU 20 g/mm(2) 10.7 +/- 4.9, 40 g/mm(2) 11.1 +/- 5; M 20 g/mm(2) 7.3 +/- 3.1, 40 g/mm(2) 7.9 +/- .2. Cement type, luting pressure, and the interaction of these two factors had significant influences on dentin bond strength, with RU and P outperforming M. RU and P significantly benefited from the increase in luting pressure. In enamel, the type of cement was a significant factor for adhesion, with P yielding the highest and M the lowest strength. The measured bond strengths corresponded with the morphological results. CONCLUSION: Interfacial strength and adaptation of self-etching and self-adhesive dual-curing cements are enhanced if a seating force greater than finger pressure is maintained throughout the initial self-curing period.

The effect of immediate versus delayed cementation on the retention of different types of fiber post in canals obturated using a eugenol sealer.

Post can be placed immediately after the completion of the endodontic procedure or at a later stage after setting of the sealer. In this in vitro study, post space preparation and post cementation were performed immediately (group 1), 24 h (group 2), and 7 days (group 3) after root filling. A control group with no root canal obturation was included (group 4). Each group was further divided into three subgroups, according to the post type and to the materials used for luting the post. A push-out test was performed to evaluate post-root canal dentin interfacial strength. Differences among experimental groups were analyzed with two-way ANOVA and the Tukey test. Significant differences (p < 0.05) in interfacial strengths were observed for the factors post cementation interval and post type. Clinicians should be careful in performing immediate cementation of fiber posts, as delayed cementation shows higher post-dentin interfacial strengths irrespective of the post type.

Effect of hygroscopic expansion on the push-out resistance of glass ionomer-based cements used for the luting of glass fiber posts.

This study examined the contribution of hygroscopic expansion of glass-ionomer (GIC) and resin modified glass-ionomer (RMGIC) luting cements to the push-out resistance of fiber posts. Glass fiber posts were luted to post spaces using different cements. Experimental specimens were stored in water, while control specimens were desiccated and stored in mineral oil to eliminate water from intraradicular dentinal tubules and/or the external environment that could have contributed to hygroscopic expansion of the cements. Thin slice push-out tests revealed no difference in retention strengths of resin composite cements that were stored in water or oil. Conversely, GIC and RMGIC cements exhibited increased retention strengths after water sorption. As unfavorable cavity geometry is taxing to dentin bond integrity in root canals, a strategy that relies on increasing the frictional resistance to post dislodgement via delayed hygroscopic expansion of glass-ionomer based materials may be a more pragmatic approach to fiber post retention.

Post-surface conditioning improves interfacial adhesion in post/core restorations.

OBJECTIVES: To verify the influence of different etching procedures of the post-surface on microtensile bond strength values between fiber posts and composite core materials. METHODS: 60 DT Light Posts were divided into 10 subgroups using five different chemical surface treatments and two composite materials to build-up the abutment. Chemical surface treatments including etching with potassium permanganate; treatment with 10% hydrogen peroxide; treatment with 21% sodium ethoxide; etching with potassium permanganate and 10 vol.% HCl; silanization (control group) were performed on the post's surface. The build-up was performed using (A) Core Paste XP (Dent Mat) and (B) Unifil Flow (GC). Two samples of each group were randomly selected to investigate the morphologic aspect of the post/core interface with a scanning electron microscope (SEM). The remaining specimens were cut so as to obtain microtensile sticks that were loaded in tension at a cross-head speed of 1mm/min until failure. The statistical analysis was performed using two-way ANOVA and the Tukey's test for post-hoc comparisons (alpha=0.05). RESULTS: SEM examination showed an interpenetrating adhesion network between the treated fiber post-surface and the composite material in all the groups tested. The results achieved with potassium permanganate had a significant influence on microtensile interfacial bond strength values with both the tested materials. Post-superficial treatments enhanced the bond strength particularly of Core Paste XP. SIGNIFICANCE: Etching procedures showed a similar effect on the post-surface and enhanced the adhesion of composite core build-ups as a result of micromechanical and chemical retention.

Noninvasive pit and fissure sealing: microtensile bond strength to intact bovine enamel of different pit and fissure sealants in a simplified fissure model.

PURPOSE: To measure the microtensile bond strength of different pit and fissure sealants in a simplified fissure model. MATERIALS AND METHODS: Twenty extracted bovine mandibular permanent incisors were randomly divided into 4 groups for treatment: G1: 35% phosphoric acid/Clinpro Sealant; G2: 35% phosphoric acid/Delton; G3: Non-Rinse Conditioner/Dyract Seal; G4: 20% polyacrylic acid/Fuji IILC. Each tooth was sectioned into 6 pieces (4 x 6 mm) of buccal enamel. SEM examination was used to confirm the presence of aprismatic enamel on each tooth. Using a spacer, two pieces of etched enamel were secured to a glass slide at a mean distance of 0.6+/-0.1 mm. The space between enamel substrates was then etched/conditioned and sealed with different materials according to the tested groups. By serially cutting each double-bonded sample, multiple beam-shaped specimens about 0.8mm(2) in cross section were obtained and tested in tension (0.5 mm/min) until failure occurred at either one of the two stressed interfaces. Failure modes were classified by stereomicroscopy. RESULTS: G1 and G2 showed statistically higher bond strengths than G3 and G4. G4 demonstrated the significantly lowest bond strength. Failures were mostly adhesive in G1, G2, G3, and mainly cohesive/mixed in G4. CONCLUSION: According to this model, resin-based materials (Clinpro Sealant, Delton) showed better microtensile bond strength than compomer (Dyract Seal) or resin-modified glass ionomer (Fuji IILC).

The influence of the cutting speed on bond strength and integrity of microtensile specimens.

OBJECTIVES: To verify the influence of cutting speed during microtensile specimen preparation, on bond strength values and on the sample microscopic integrity of a single-bottle adhesive system to enamel and dentin. METHODS: Thirty sound human third molars were restored with light-cured Excite and Tetric Ceram according to manufacturers' instructions, being half in ground enamel [E], and half in flat dentin [D]. After 24 h storage in distilled water at 37 degrees C, the restored teeth were sectioned in x and y-axes under different cutting speed: 100, 200 or 400 RPM, obtaining stick shaped specimens with cross-sectional area of 1.0 mm(2). Five specimens from each experimental group were randomly selected before being loaded for SEM analysis, while the remaining samples were subjected to the microtensile bond strength test. Because the variance of dentin specimens was significantly higher than the variance of enamel samples, analysis of the influence of the cutting speed was performed separately, by substrate. RESULTS: The mean values in MPa were calculated including/excluding premature failures: E1: 24.67/27.31(a); E2: 24.03/25.81(a); E4: 19.06/21.52(b); D1: 35.80/36.33(A); D2: 35.84/36.65(A); D4: 37.78/38.50(A). In the SEM analysis, better integrity of the dentin specimens was observed when compared to the enamel samples, for which the integrity was greater in the lower cutting speed groups. SIGNIFICANCE: It can be concluded that the cutting speed is an important factor that should be considered, mainly when enamel is involved, since it may affect the bond strength results and the integrity of the specimens.