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OBJECTIVE: This case report described the use of a stamping technique associated with a bulk fill composite to restore an ICDAS 4 carious lesion on a posterior tooth. The 4-year follow-up is also presented. CLINICAL CONSIDERATIONS: A 32-year-old patient presented a carious lesion on tooth 36 with an underlying dark shadow at the dentin seen from the noncavitated enamel occlusal surface, which was compatible with an ICDAS 4 carious lesion. The lesion was radiographically detected and the caries disease was treated with dietary and hygiene habits orientations. Before accessing the lesion and selectively removing the carious tissue, an occlusal stamp was made by applying a flowable resin composite to copy the anatomy of the noncavitated enamel surface. The cavity was restored using a bulk fill resin composite (Opus Bulk Fill, FGM) with 4-mm-thick increments. Before curing the last increment, a Teflon band was adapted at the uncured bulk fill composite surface and the occlusal stamp made with the flowable composite was pressed against it to reproduce the natural characteristics and initial occlusal anatomy. The top surface was light-activated for 40 s. After 4 years, small wear could be seen in the restoration, but still within clinically acceptable levels. CONCLUSION: The occlusal stamp technique allows reproduction of the natural anatomy of teeth affected by ICDAS 4 carious lesions with good clinical longevity over 4 years. CLINICAL SIGNIFICANCE: This case report presents the use of the stamp technique to restore a tooth affected by an ICDAS 4 lesion, in which a carious process reached the dentin and the enamel anatomy was still preserved. The bulk fill resin composite associated with the occlusal stamp was chosen to quickly restore the cavity with clinical predictability. Bulk fill composites allow the insertion of up to 4-mm-thick increments and offer lower shrinkage stress, good clinical longevity and a less time-consuming procedure in cases of posterior teeth, especially if associated with the stamp technique.

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Bulk-fill composites were introduced in dentistry to accelerate clinical procedures while providing adequate outcomes. Concerns regarding the use of bigger composite increments rely on the polymerization shrinkage and shrinkage stress, which may generate gaps on the adhesive interface and result in a reduced success rate. OBJECTIVE: To evaluate the polymerization shrinkage stress of different bulk-fill resin composites and their elastic modulus. MATERIALS AND METHODS: Fourteen specimens were made for each of the nine different resin composites (seven with 12 mm3 and seven with 24 mm3): Surefill SDR flow (SDR), X-tra Base (XB), Filtek Bulk Fill Flowable (FBF), Filtek Z350XT Flow (Z3F); Tetric Evo Ceram Bulk Fill (TBF), X-tra Fil (XF), Filtek Bulk Fill (FBP), Admira Xtra Fusion (ADM) and Filtek Z350 XT (Z3XT). Linear shrinkage stress was evaluated for 300 s with the aid of a linear shrinkage device adapted to a Universal Testing Machine. For each composite group, seven additional specimens (2x2x25 mm) were made and Young's modulus was evaluated with a 3-point bending device adapted in a Universal Testing Machine with 0.5 mm/min crosshead speed and 50 KgF loading cell. RESULTS: For 12 mm3 specimens, three-way ANOVA showed that only SDR and TBF generated lower stress after 20 s. Considering 300 s, TBF, SDR, and XF generated the lowest stress, followed by ADM, FBP, XB, and FBF, which were similar to Z3XT. Z3F generated the highest stress values for all time points. Considering 24 mm3 specimens after 20 s, all bulk fill composites generated lower stress than Z3XT, except XB. After 300 s, SDR, FBP, and ADM generated the lowest stress, followed by TBF and XF. For elastic modulus, one-way ANOVA showed that FBF, SDR, Z3F, and ADM presented the lowest values, followed by XB and TBF. FBP, Z3XT, and XF presented the highest elastic modulus among the evaluated composites. CONCLUSIONS: Bulk-fill resin composites presented equal to lower shrinkage stress generation when compared to conventional composites, especially when bigger increments were evaluated. Bulk-fill composites showed a wide range of elastic modulus values, but usually similar to "regular" composites.

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OBJECTIVES: The aim of this in vitro study was to evaluate the bonding strength of non-simplified dentin bonding systems (DBS) to dentin irradiated with a diode laser (970 nm) immediately and after 12 months of water storage following either primer or bond application. MATERIAL AND METHODS: The experimental design included three different factors: DBS type [AdperTM Scotchbond Multipurpose (MP) and Clearfil™ SE Bond (CSE)], irradiation [without irradiation - control (C), irradiation after primer application (AP), and irradiation after bond application (AB)], and time [initial (I) and after 12 months of water storage (12 m)]. Sixty sound human third molars (n = 10) were obtained, and their flat occlusal dentin areas were prepared and standardized. Laser irradiation was performed in the contact mode perpendicular to the dental surface over an automatically selected scanning area at a pulse energy of 0.8 W, frequency of 10 Hz, and energy density of 66.67 J/cm2. After 7 days of treatment, the specimens were cut, and half of them were subjected to microtensile testing (500 N/0.05 mm/min), whereas the remaining sticks were examined after 12 months of water storage. The obtained data were analyzed by three-way analysis of variance (ANOVA) followed by a Tukey test (p<0.05). The observed fracture modes were investigated using a portable digital microscope with a magnification of 40x. RESULTS: Among the utilized DBS, MP generally exhibited higher bond strengths, but did not always differ from CSE under similar conditions. The irradiation factor was statistically significant only for the MP/AB groups. After 12 months of storage, all groups demonstrated a significant reduction in the bond strength, whereas the results of fracture analysis showed a predominance of the adhesive type. CONCLUSIONS: The laser treatment of non-simplified DBS was not able to stabilize their bonding characteristics after 12 months.

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BACKGROUND: The use of hybrid-light (HL) during in-office teeth bleaching can provide faster and reliable results after a single bleaching session, especially if associated with previous acid etching. The present in vivo, interventional, split-mouth, triple-blinded and randomized study evaluated the efficiency of a HL, with and without prior enamel acid etching, assessing the gel application time, degree of color change, sensitivity and treatment stability up to 12 months. METHODS: Thirty-four patients were selected and randomly divided into four groups. The color was evaluated using a spectrophotometer with the CIELab color system, and a VAS questionnaire was used to evaluate the sensitivity. Both upper and lower hemiarches (GI and III) received enamel acid etching with 37% phosphoric acid for 15 s prior to the application of 35% hydrogen peroxide gel (HP). For GI and II, HP was applied on both dental arches for 3-4 consecutive applications and activated by HL (2 × 3' activations with 1' interval); and 3 × 15' (HP) for GIII and IV without HL. Patients returned in 24 h, 1 week, 1-, 6- and 12-months intervals. The clinical operator was different from the clinical measurements operator. RESULTS: After 3-way ANOVA, Tukey's, Wilcoxon and Mann-Whitney tests, all with p < 0.05, no statistical differences were observed between the groups regarding color change (ΔE) and sensitivity in all evaluations. The lowest gel application time was observed for GII (acid etch + HL), followed by GI (HL). CONCLUSIONS: The present study's results reveal the advantages of HL associated with acid etching prior to in office bleaching.

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PURPOSE: To evaluate the color change caused by post-irradiation conversion (ΔE24h and ΔE8 days ) and artificial aging (ΔEAGING ) of resin cements light activated through ceramics of different opacities immediately and 6 minutes after manipulating the material. MATERIALS AND METHODS: Resin cement disks (Allcem and LuxaCore) were light activated through ceramics (without ceramic, e.max HT, LT, and MO) immediately and 6 minutes after the manipulation (n = 10). Spectrophotometry was used to evaluate ΔE24h and ΔE8 days after 37˚C-dry-dark-storage for 24 hours and 8 days, and ΔEAGING after 60˚C-water-storage for 24 hours. Data were analyzed with three-way ANOVA and Tukey's HSD (α = 0.05). RESULTS: Regarding the post-irradiation color change, significant differences were found between the cements (p < 0.0001), light activation protocols (p = 0.037), and ceramics (p < 0.001). The immediate activation (16.2 ± 0.1) showed lower ΔE values than the delayed activation (16.5 ± 0.1). Ceramics influenced the ΔE values as follows: MO (14.0 ± 1.2) < LT (14.9 ± 1.2) ≈ HT (15.4 ± 1.2) < control (21.2 ± 1.2). Regarding ΔEAGING , significant differences were found between cements (p < 0.001), light activation (p = 0.006), and ceramics (p < 0.001). The delayed activation (8.4 ± 0.1) showed lower values than the immediate activation (8.9 ± 0.1). Ceramic spacers influenced ΔEAGING as follows: control (5.6 ± 0.2) < MO (6.6 ± 0.2) < HT (11.0 ± 0.2) ≈ LT (11.5 ± 0.2). CONCLUSION: The delayed light activation resulted in increased color stability, while the ceramic interposition resulted in lower color stability.

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OBJECTIVE: This study aimed to investigate the effect of laser diode irradiation on the degree of conversion (DC), water sorption (WS), and water solubility (WSB) of these bonding systems in an attempt to improve their physico-mechanical resistance. MATERIAL AND METHODS: Two bonding agents were tested: a two-step total-etch system [Adper™ Single Bond 2, 3M ESPE (SB)] and a universal system [Adper™ Single Bond Universal, 3M ESPE (SU)]. Square-shaped specimens were prepared and assigned into 4 groups (n=5): SB and SU (control groups - no laser irradiation) and SB-L and SU-L [SB and SU laser (L) - irradiated groups]. DC was assessed using Fourier transform infrared spectroscopy with attenuated total reflectance. Additional uncured resin samples (≈3.0 µL, n=5) of each adhesive were also scanned for final DC calculation. For WS/WSB tests, similar specimens (n=10) were prepared and measured by monitoring the mass changes after dehydration/water storage cycles. For both tests, adhesive fluids were dropped into standardized Teflon molds (6.0×6.0×1.0 mm), irradiated with a 970-nm laser diode, and then polymerized with an LED-curing unit (1 W/cm2). RESULTS: Laser irradiation immediately before photopolymerization increased the DC (%) of the tested adhesives: SB-L>SB>SU-L>SU. For WS/WSB (µg/mm3), only the dentin bonding system (DBS) was a significant factor (p<0.05): SB>SU. CONCLUSION: Irradiation with a laser diode improved the degree of conversion of all tested simplified dentin bonding systems, with no impact on water sorption and solubility.

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Abstract Simplified dentin-bonding systems are clinically employed for most adhesive procedures, and they are prone to hydrolytic degradation. Objective This study aimed to investigate the effect of laser diode irradiation on the degree of conversion (DC), water sorption (WS), and water solubility (WSB) of these bonding systems in an attempt to improve their physico-mechanical resistance. Material and Methods Two bonding agents were tested: a two-step total-etch system [Adper™ Single Bond 2, 3M ESPE (SB)] and a universal system [Adper™ Single Bond Universal, 3M ESPE (SU)]. Square-shaped specimens were prepared and assigned into 4 groups (n=5): SB and SU (control groups - no laser irradiation) and SB-L and SU-L [SB and SU laser (L) - irradiated groups]. DC was assessed using Fourier transform infrared spectroscopy with attenuated total reflectance. Additional uncured resin samples (≈3.0 µL, n=5) of each adhesive were also scanned for final DC calculation. For WS/WSB tests, similar specimens (n=10) were prepared and measured by monitoring the mass changes after dehydration/water storage cycles. For both tests, adhesive fluids were dropped into standardized Teflon molds (6.0×6.0×1.0 mm), irradiated with a 970-nm laser diode, and then polymerized with an LED-curing unit (1 W/cm2). Results Laser irradiation immediately before photopolymerization increased the DC (%) of the tested adhesives: SB-L>SB>SU-L>SU. For WS/WSB (μg/mm3), only the dentin bonding system (DBS) was a significant factor (p<0.05): SB>SU. Conclusion Irradiation with a laser diode improved the degree of conversion of all tested simplified dentin bonding systems, with no impact on water sorption and solubility.

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Often, young patients (≤30 years old) present with carious lesions that progress acutely, compromising a large amount of tooth structure. In these cases, a treatment to prevent the occurrence of pulp exposure and promote remineralization of caries-affected dentin is necessary to maintain healthy dental structure and allow more conservative interventions. The approach will be different when pulp exposure occurs: The therapeutic treatments will be focused on reparative dentin formation and prevention of microorganisms penetrating the pulp organ. Due to the different possible treatments that can be performed to avoid pulp necrosis and the various materials that can be used for this purpose, professionals may have some difficulties understanding all the indications for conservative pulp treatments. The objective of this article is to describe and discuss a successful pulp capping and stepwise excavation associated with restorative treatment for deep caries lesions of anterior upper teeth.

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Tooth wear associated with bone loss, gingival recessions and root exposure of the anterior teeth determine the characteristics of an aged smile. The present clinical case reports the aesthetic treatment of a middle-aged patient who had a prematurely aged smile. After anamnesis and physical examination, it was found that episodes of bone loss had occurred, however, previous periodontal treatment had satisfactorily controlled the disease. And yet it was also observed wear of the upper anterior teeth and fracture on tooth 11. Treatment plan included the confection of direct veneers with composite resin, without the need for tooth structure wear. At the end of the first session, it was observed that although an aesthetic result was already achieved, the ratio of height and width of the incisors had not yet been standardized. Thus, orthodontic rubbers were used for three days for tooth movement and increase of mesiodistal dimension of the central and lateral incisors. The present case demonstrates excellent aesthetic results and patient satisfaction. It was concluded that in the current case report it was possible to satisfactorily rejuvenate smile with direct application of composite resin (AU).

O desgaste dentário associado à perda óssea, recessão gengival e exposição radicular dos dentes anteriores determinam características de um sorriso envelhecido. O presente caso clínico relata o tratamento estético de uma paciente de meia idade, que apresentava sorriso precocemente envelhecido. Após anamnese e exame físico, constatou-se que episódios de perda óssea ocorreram, no entanto, o tratamento periodontal prévio já havia controlado a doença de forma satisfatória. Observou-se ainda desgaste dos dentes anteriores superiores e fratura no elemento ente 11. O plano de tratamento incluiu a realização de facetas diretas de resina composta, sem a necessidade de desgaste da estrutura dentária. Ao final da primeira sessão, observou-se que, apesar de um resultado estético já obtido, a proporção de altura e largura dos incisivos não havia ainda sido normalizada. Assim, borrachas ortodônticas foram utilizadas por três dias para movimentação dos dentes e aumento da dimensão mésio-distal dos incisivos centrais e laterais. Este caso mostra excelentes resultados estéticos e satisfação do paciente. Concluiu-se que, no presente caso clínico, foi possível rejuvenescer o sorriso de forma satisfatória com aplicação de resinas compostas diretas (AU).

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The use of light sources in the bleaching process reduces the time required and promotes satisfactory results. However, these light sources can cause an increase in the pulp temperature. Objective The purpose of the present study was to measure the increase in intrapulpal temperature induced by different light-activated bleaching procedures with and without the use of a bleaching gel. Material and Methods A human maxillary central incisor was sectioned 2 mm below the cementoenamel junction. A K-type thermocouple probe was introduced into the pulp chamber. A 35% hydrogen peroxide bleaching gel was applied to the vestibular tooth surface. The light units used were a conventional halogen, a hybrid light (only LED and LED/Laser), a high intensity LED, and a green LED light. Temperature increase values were compared by two-way ANOVA and Tukey´s tests (p<0.05). Results There were statistically significant differences in temperature increases between the different light sources used and between the same light sources with and without the use of a bleaching gel. The presence of a bleaching gel generated an increase in intra-pulpal temperature in groups activated with halogen light, hybrid light, and high intensity LED. Compared to the other light sources, the conventional halogen lamp applied over the bleaching gel induced a significant increase in temperature (3.83±0.41°C). The green LED unit with and without gel application did not produce any significant intrapulpal temperature variations. Conclusion In the present study, the conventional halogen lamp caused the highest increase in intrapulpal temperature, and the green LED caused the least. There was an increase in temperature with all lights tested and the maximum temperature remained below the critical level (5.5°C). The addition of a bleaching gel led to a higher increase in intrapulpal temperatures.

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ABSTRACT The use of light sources in the bleaching process reduces the time required and promotes satisfactory results. However, these light sources can cause an increase in the pulp temperature. Objective The purpose of the present study was to measure the increase in intrapulpal temperature induced by different light-activated bleaching procedures with and without the use of a bleaching gel. Material and Methods A human maxillary central incisor was sectioned 2 mm below the cementoenamel junction. A K-type thermocouple probe was introduced into the pulp chamber. A 35% hydrogen peroxide bleaching gel was applied to the vestibular tooth surface. The light units used were a conventional halogen, a hybrid light (only LED and LED/Laser), a high intensity LED, and a green LED light. Temperature increase values were compared by two-way ANOVA and Tukey´s tests (p<0.05). Results There were statistically significant differences in temperature increases between the different light sources used and between the same light sources with and without the use of a bleaching gel. The presence of a bleaching gel generated an increase in intra-pulpal temperature in groups activated with halogen light, hybrid light, and high intensity LED. Compared to the other light sources, the conventional halogen lamp applied over the bleaching gel induced a significant increase in temperature (3.83±0.41°C). The green LED unit with and without gel application did not produce any significant intrapulpal temperature variations. Conclusion In the present study, the conventional halogen lamp caused the highest increase in intrapulpal temperature, and the green LED caused the least. There was an increase in temperature with all lights tested and the maximum temperature remained below the critical level (5.5°C). The addition of a bleaching gel led to a higher increase in intrapulpal temperatures.

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A pigmentação melânica gengival é uma condição clínica mais prevalente em indivíduos da raça negra e oriental, consistindo frequentemente em um problema estético. Embora a recidiva seja imprevisível, vários tratamentos são propostos, entre eles a mucodermoabrasão com diferentes instrumentos. O objetivo do presente relato de caso clínico foi demonstrar duas técnicas para resolução desses casos: emprego dos gengivótomos e de uma ponta de cerâmica em alta rotação.

Gingival melanin pigmentation is a clinical condition, more prevalent in oriental and black people, and may generate esthetical problems. Despite the fact that recurrence is unpredictable, different treatments are proposed, such as epithelial abrasion with different instruments. The objective of the present case report is to show two different techniques for resolution of such cases: use of Kirkland periodontal knife, and abrasive ceramic burs in high speed.

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Restaurações livres de metal (metal free) têm se tornado bastante populares devido à evolução dos materiais e das técnicas de preparo e cimentação, associando adequadas propriedades físico-mecânicas e estéticas com resultados satisfatórios a longo prazo. O uso de pastas de teste (pastas try-in) e cimentos fotopolimerizáveis facilitam a técnica de cimentação. O objetivo do presente relato de caso clínico é demonstrar uma sequência de restabelecimento estético do sorriso com restaurações metal free, empregando um protocolo previsível (AU).

Metal free restorations have became very popular due to materials and preparation and cementation techniques evolution, associating adequate physico-mechanical and esthetics properties with adequate long term results. The use of try-in pastes and light curing cements facilitates the cementation technique. The objective of the present case report is to show a sequence of smile aesthetic rehabilitation with metal free restorations, using a predictable protocol (AU).

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Tratamentos estéticos com demanda por excelência são corriqueiros nas clínicas odontológicas especializadas, sendo cada vez mais procurados e realizados em sessão única de tratamento. Esses procedimentos com sessão única podem ser indicados por imediatismo, urgência dos pacientes ou pela indisponibilidade de locomoção, uma vez que muitos pacientes buscam tratamentos especializados em cidades distantes de suas residências. O presente relato de dois casos clínicos descreve as técnicas e estratégias de tratamento para realização do clareamento dentário e de restaurações adesivas na mesma sessão, por meio da utilização de agentes antioxidantes. O clareamento em consultório foi realizado com gel de peróxido de hidrogênio 35% (Lase peróxido de Flex, DMC), ativado com LED (Laser BrightMax Quattro, MMO). Em função da presença de íons oxigênio na matriz do esmalte e dentina após o clareamento dental, esses íons podem inibir a adequada polimerização dos sistemas adesivos e da resina composta, comprometendo o procedimento restaurador. Sendo água bicarbonatada (Neutralize, Lase peróxido Flex Kit, DMC) aplicada para remover o oxigênio residual, após preparo cavitário e antes do condicionamento ácido e aplicação do adesivo. As restaurações foram realizadas com técnica incremental e resina composta cor A2/B2 de dentina (NG brilhante, Coltene) e A1/B1 de esmalte (NG brilhante, Coltene). Os procedimentos de acabamento e polimento também foram realizados na mesma sessão. Após 3 meses de controle foi possível observar, que em ambos os casos, o tratamento estético obteve bastante sucesso, sem qualquer deterioração visível da interface resina-esmalte (AU).

Aesthetic treatments with demand for excellence are commonplace in specialized dental clinics, increasingly popular and performed in a single treatment session. These procedures performed in a single session may be indicated by immediacy, patients urgency or unavailability of transportation, since many patients seek specialized treatment in cities far away from their homes. This report of two cases describes treatment techniques and strategies to perform dental bleaching and adhesive restorations in the same session through the use of antioxidants. Bleaching was carried out in-office with 35% hydrogen peroxide gel (Lase Peroxide Flex, DMC), activated with LED (Laser BrightMax Quattro, MMO). Due to the presence of oxygen ions in the enamel matrix and dentin after bleaching, these ions can inhibit the proper polymerization of the adhesive systems and composite resin, compromising the restorative procedure. Bicarbonated water (Neutralize, Lase Peroxide Flex Kit, DMC) is applied to remove residual oxygen after cavity preparation and before the acid etching and adhesive application. Restorations were performed with incremental technique and composite dentin color A2/B2 (bright NG, Coltene) and A1/B1 enamel (bright NG, Coltene). Finishing and polishing procedures were also performed in the same session. After 3 months, it was observed that in both cases, the aesthetic treatment achieved great success without any visible deterioration of the resin/enamel interface (AU).

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The purpose of this clinical case description article was to present the planning sequence, indication, treatment and performance to obtain a crown of the Endocrown type. This clinical case description article illustrates a therapeutic option for functional and esthetic rehabilitation of a devitalized mandibular molar, presenting a small amount of remaining coronal tooth structure, by means of cementing a pure porcelain crown of the Endocrowntype (Adhesive Endodontic Crown). A 39-year-oldwoman presented to the Graduate clinic of the Bauru Dental School (FOB), University of São Paulo (USP),with the complaint that tooth #36 had an extensive and unsatisfactory composite resin restoration. The lithium disilicate-based system of monolithic porcelain was used with the lost wax technique. This therapy promoted the stability and retention of the indirect restoration, without the need for performing reconstruction of the above mentioned tooth, either by means of a cast metal core or reconstruction with intracanal post, there by reducing the treatment time. After the tooth preparation, the provisional restoration was done with acrylic resin to determine if the retention and stability of the remaining tooth was adequate to receive the indirect. The characteristics of the internal and external walls of the dental remnants, cervical termination, impression-taking, laboratory stages and adhesive cementation will be discussed. The major advantage of indicating an endocrown is the use of the dental remnants it self, particularly the pulp chamber, to promote retention and stability in cases without adequate height for performing complete dental and crown reconstruction...

O objetivo deste artigo de descrição de caso clínico foi apresentar a sequência de planejamento, indicação, tratamento e execução de uma coroa do tipo Endocrown (Coroa Endodôntica Adesiva).Este artigo ilustra uma opção terapêutica para reabilitação funcional e estética de um molar inferior desvitalizado, apresentando uma pequena quantidade de remanescente coronário, por meio da cimentação de uma coroa pura de porcelana do tipo Endocrown. Uma mulher de 39 anos de idade, apresentou-se à clínica de Pós-Graduação da Faculdade de Odontologia de Bauru (FOB) da Universidade de São Paulo(USP), com a queixa de uma extensa e insatisfatória restauração de resina composta no dente 36. O sistema monolítico de porcelana à base de dissilicato de lítio foi utilizado com a técnica da cera perdida.Esta técnica promoveu a estabilidade e a retenção da restauração indireta, sem a necessidade de realizara reconstrução do dente 36, quer por meio de um núcleo metálico fundido ou reconstrução com pino intra canal, reduzindo assim o tempo de tratamento.Após o preparo do dente, realizou-se a restauração provisória com resina acrílica e verificou-se se a retenção e estabilidade do remanescente dentário era adequada para receber a restauração do tipo Endocrown. As características das paredes internas e externas do preparo do remanescente dentário,término cervical, moldagem, etapas laboratoriais e de cimentação são discutidas. A principal vantagem da indicação de uma coroa do tipo Endocrown é a utilização do próprio remanescente dentário,particularmente a câmara pulpar, para promover a retenção e estabilidade em casos onde não haja altura adequada para a reconstrução coronária...

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OBJECTIVE: This in vitro study evaluated the effect of different bleaching protocols and the variation of pH levels of bleaching gels regarding roughness and wear of bovine enamel, after in-office bleaching protocols and brushing. MATERIALS AND METHODS: Ninety fragments were randomly divided into nine groups: C, control; WHP15, 35% hydrogen peroxide (HP) (Whiteness HP, FGM) three gel applications of 15 min each, three sessions with 1 week intervals; WHP45, 35% HP (Whiteness HP) one application/45 min, three sessions with 1 week intervals; LPS, 35% HP (Lase Peroxide, DMC) plus hybrid light (HL) [light-emitting diode (LED)/diode laser], four applications/7 min 30 sec (6 min of HL activation), one session; LPSII, 25% HP (Lase Peroxide II, DMC) plus HL, four applications/7 min 30 sec (6 min of HL activation), one session; LPL, 15% HP (Lase Peroxide Light, DMC) four applications/7 min 30 sec (6 min of HL activation), one session; WO, 35% HP (Whitegold Office, Dentsply) three applications/15 min, three sessions with 1 week intervals; WBC40, 35% HP (Whiteness HP Blue Calcium, FGM) one application/40 min, three sessions with 1 week intervals; and WBC50, 20% HP (Whiteness HP Blue Calcium) one application/50 min, three sessions with 1 week intervals. The median pH values were determined utilizing a pH meter during the initial and final gel applications. A rugosimeter was utilized to evaluate the surface roughness (Ra) before and after bleaching and brushing (100,000 strokes), and the surface wear after brushing. RESULTS: For the results of the pH values, there was a decrease in the pH levels from the initial to the final bleaching time, except for the WBC50. The WO and WBC40 groups exhibited higher pH values. For the results of roughness and wear, there was an increase in surface roughness and wear among the groups. CONCLUSIONS: The pH values tended to decrease from the initial to the final bleaching. After tooth brushing, bleaching procedures with lower pH products provided a significant increase in enamel wear and surface roughness.

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Introduction: The silorane-based resin appears aiming to minimize the effects of polymerization shrinkage, but other properties must be studied. Objective: To evaluate the polymerization depth of two composites with different organic matrix. Material and methods: 80 cylindrical specimens were prepared using a metallic matrix, with three layers (top, middle and bottom), 1 mm high and 5 mm in diameter. The specimens were divided into eight groups (n = 10) according to the composite resins: Filtek P90 (3M/ESPE); Filtek Z250 (3M/ESPE), light-cured with a LED device with different irradiance and times (600mW/cm2 x 40s, 1000mW/cm2 x 40s, 1000mW/cm2 x 20s; 1400mW/cm2 x 20s). The irradiance was controlled by placing plastic rings coupled to the device's tip. Immediately after polymerization, the specimens' layers were separated and five Knoop microhardness readings (initial hardness) were performed on each one of the four layers (0, 1, 2, and 3 mm). After 7 day storage in water at 37ºC, new readings were performed (final microhardness). The data were analyzed by four-way ANOVA (resin, energy density, depth and time) and Tukey test (α = 0.05). Results: The microhardness decreased with the depth increasing both in the initial and 7 day readings. The hardness increased with the highest power densities. The resin P90 had lower hardness values. Conclusion: The silorane-based resin showed Knoop microhardness values significant smaller than those of methacrylate-based resin in almost all evaluated parameters. However, both presented similar behaviors in relation to the curing depth.

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Facetas minimamente invasivas, também conhecidas como ôlentes de contatoõ, têm sido consideradas uma alternativa interessante para tratar problemas estéticos nos dentes anteriores. O presente relato de caso descreve passo a passo o tratamento de diastemas múltiplos com facetas minimamente invasivas, e discute tópicos importantes relacionados a este assunto quanto a indicações, materiais utilizados e longevidade destes tipos de restaurações...

Minimally invasive veneers, also known as ôcontact lensesõ, are being considered an interesting alternative for aesthetic rehabilitation of anterior teeth. This case report describes, step by the step the treatment of multiple diastemas with minimally invasive veneers, and addresses important issues related to this topic concerning indications, materials and longevity of these type of restorations...

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OBJECTIVE: Tooth bleaching tends to increase enamel roughness and porosity, in addition to reducing surface microhardness. The aim of this in vitro study was to evaluate the effects of bleaching treatments using different hydrogen peroxide (HP) concentrations, with and without light activation on bovine enamel microhardness. MATERIALS AND METHODS: The buccal surfaces of sixty bovine incisors were flattened and polished and the enamel specimens were divided into six groups: G1 : c0 ontrol, exposed to artificial saliva; G2: 35% HP applied in two sessions (45' each); G3: 35% HP applied in two sessions (3 × 15' each); G4: 35% HP applied in one session (3 × 7'30") plus hybrid light (HL); G5: 25% HP applied in one session (3 × 7'30") plus HL; and G6: 15% HP applied in one session (3 × 7'30") plus HL. After the treatment, the enamel specimens were stored in artificial saliva. The surface microhardness (Knoop) was measured at the baseline, 24 h and 7 days after bleaching. The data was analyzed using the ANOVA test, followed by the Tukey-Krummer test (P < 0.05). RESULTS: All bleaching procedures lead to a decrease in surface microhardness when compared with the control group after 24 h. The lowest change in surface microhardness was found in the specimens treated with 15% HP plus HL. However, 35% HP plus HL induced the highest decrease in surface microhardness. After 7 days of remineralization, the surface microhardness returned to normal levels for all bleached specimens. CONCLUSION: Therefore, it can be concluded that the bleaching protocols caused a slight enamel surface alteration. However, the remineralization process minimized these effects.

RESUMO

Laser irradiation after the immediate application of dentin bonding systems (DBSs) and prior to their polymerization has been proposed to increase bond strength. The objective of this study was to evaluate the effect of diode laser irradiation (λ = 970 nm) on simplified DBSs through microtensile bond strength tests. Forty healthy human molars were randomly distributed among four groups (n = 10) according to DBSs used [Adper™ SingleBond 2 (SB) and Adper™ EasyOne (EO)], and the respective groups were irradiated with a diode laser (SB-L and EO-L). After bonding procedures and composite resin build-ups, teeth were stored in deionized water for 7 days and then sectioned to obtain stick-shaped specimens (1.0 mm2). The microtensile test was performed at 0.5 mm/min, yielding bond strength values in MPa, which were evaluated by two-way ANOVA followed by Tukey's test (p < 0.05) for individual comparisons. For both adhesive systems, diode laser irradiation promoted significant increases in bond strength values (SB: 33.49 ± 6.77; SB-L: 43.69 ± 8.15; EO: 19.67 ± 5.86; EO-L: 29.87 ± 6.98). These results suggest that diode laser irradiation is a promising technique for achieving better performance of adhesive systems on dentin.

Assuntos