Insertion methods and gap/void formation in atraumatic restorative technique: A micro-CT analysis

Abstract Wetting the dentin is critical to atraumatic restorative treatment. The conventional insertion can be challenging when using high-viscosity glass-ionomer cement. This study evaluated the formation of gaps and voids after three insertion methods using micro-CT. Teeth underwent removal of occlusal and proximal caries through the atraumatic restorative treatment technique. Then, they were fixed in an artificial dental arch to simulate the clinical condition and were restored using three insertion methods: conventional, Centrix injection, and double-filling. Previous dentin conditioning procedures, steel matrix and wooden wedge application, and post-insertion procedures (digital compression and surface protection) were the same. The material was inserted using a manual instrument in the conventional technique and was inserted with a syringe in the Centrix injection group. In the double-filling technique, the tooth received a first layer of a flowable ionomer (through modifying the powder/liquid ratio), and a second layer (with standard ratio) was applied before the final set of the first one. A micro-CT unit scanned each tooth before and after restoration. Each cavity was defined as the volume of interest, and the volumes of gaps and voids were calculated. Data were analyzed using one-way ANOVA and Tukey posthoc test (p < .05). Double-filling had improved filling volume with lower values for gap volume, followed by Centrix injection. The conventional technique had the highest gap volume. No statistically significant difference was observed for void volume. Double-filling demonstrated fewer gaps, followed by Centrix injection, which is critical to obtain better adhesive, remineralizing, and antibacterial activities.

Resumo O molhamento da dentina parcialmente desmineralizada no fundo da cavidade dentária é fundamental para o sucesso do tratamento restaurador atraumático. No entanto, o método de inserção convencional pode ser desafiador ao usar cimento de ionômero de vidro de alta viscosidade. Este estudo avaliou a formação de gaps e vazios internos após três métodos de inserção de cimento de ionômero de vidro de alta viscosidade usando micro-CT. Dez terceiros molares foram submetidos à remoção de cárie oclusal através da técnica de tratamento restaurador atraumático e complementação proximal (com ou sem lesão pré-existente). Em seguida, foram fixados em uma arcada dentária artificial para simular a condição clínica. Os dentes foram restaurados usando a técnica de tratamento restaurador atraumático com três métodos de inserção: convencional, injeção Centrix e dupla inserção. Os procedimentos anteriores de condicionamento dentinário, inserção de matriz de aço, aplicação de cunha de madeira e procedimentos pós-inserção do material (como compressão digital e proteção de superfície) foram os mesmos para os três grupos testados. O material foi inserido com instrumento manual na técnica convencional, seguindo a metodologia clássica do tratamento restaurador atraumático. O material foi inserido com um dispositivo desenvolvido especificamente para esse fim na técnica de inserção com seringa tipo Centrix. Na técnica de dupla obturação, o dente recebeu uma primeira camada do cimento de ionômero de vidro mais fluido (obtido através da modificação da relação pó/líquido), e uma segunda camada (com relação pó/líquido padrão) foi aplicada antes da presa final da primeira. Um micro-CT escaneou cada dente antes e depois da restauração. Cada cavidade foi definida como o volume de interesse, e os volumes de gaps e vazios foram calculados. Os dados foram analisados por ANOVA one-way e teste post-hoc de Tukey com nível de significância de 5%. A dupla inserção melhorou significativamente o volume de preenchimento com valores percentuais mais baixos para o volume do gap, seguido pela injeção com seringa tipo Centrix. A técnica convencional apresentou o maior percentual de volume de gap. Nenhuma diferença estatisticamente significativa foi observada para o volume de vazios internos. O grupo de dupla inserção demonstrou menor formação de gaps, seguido pelo grupo de injeção com seringa tipo Centrix, que é fundamental para obter melhores atividades adesivas, remineralizantes e antibacterianas.

Effect of desensitizing dentifrices on eroded dentin wettability / Efeito de dentifrícios dessensibilizantes na molhabilidade da dentina erodida

Objective: To analyze the wettability on the surface of eroded dentin in teeth submitted to abrasive wear with desensitizing dentifrices. Material and Methods: Bovine dentin specimens were polished and immersed in 10 mL of citric acid (pH=3.2) for 2 h. The eroded specimens were submitted to mechanic brushing according to the 4 dentifrices adopted: Colgate Total (control); Colgate Sensitive Pro-Relief; Sensodyne Repair & Protect; or Sensodyne Rapid Relief. Afterwards, it was conditioned in 37% aqueous phosphoric acid solution. Wettability of 80 specimens (n=10) brushed for 7 or 21 days was evaluated by measuring the contact angle between the dentin surface and a drop of the adhesive Single Bond Universal® (3M) with a goniometer. Changes in the surface morphology of 12 specimens (n = 3) brushed for 21 days were followed by confocal laser scanning microscopy (CLSM). Data were analyzed by two-way ANOVA and Tukey test (p > 0.05). Results: Groups treated with desensitizing dentifrices did not differ significantly (p ≤ 0.05). Surface treatment and abrasive wear did not interact significantly (p ≤ 0.05). Brushing along 7 days gave the smallest contact angle value (p ≥ 0.05). CLSM images showed morphological changes for all the groups. Conclusion: The desensitizing dentifrices did not interfere in eroded dentin wettability after brushing along 7 or 21 days. Brushing with any of the dentifrices along 21 days promoted open dentinal tubules.(AU)

Objetivo: Analisar a aplicação de um adesivo na superfície de dentina erodida em dentes submetidos ao desgaste abrasivo com agentes dessensibilizantes. Material e Métodos: Espécimes de dentina bovina foram polidos e imersos em 10 mL de ácido cítrico (pH=3,2) por 2 h. Os espécimes erodidos foram submetidos à escovação mecânica de acordo com os 4 dentifrícios adotados: Colgate Total (controle); Colgate Sensitive Pro-Alívio; Sensodyne Repair & Protect; ou Sensodyne Rápido Alívio. Em seguida, foram condicionados em ácido fosfórico a 37%. A molhabilidade de 80 espécimes (n=10) escovados por 7 ou 21 dias foi avaliada medindo-se o ângulo de contato entre a superfície dentinária com uma gota do adesivo Single Bond Universal® (3M) por um goniômetro. Alterações na morfologia da superfície de 12 espécimes (n = 3) escovados por 21 dias foram seguidos por Microscopia Confocal de Varredura a Laser (MCVL). Os dados foram analisados por ANOVA dois fatores e teste de Tukey (p > 0,05). Resultados: Os grupos tratados com dentifrícios dessensibilizantes não diferiram significativamente (p ≤ 0,05). O tratamento de superfície e o desgaste abrasivo não interagiram significativamente (p ≤ 0,05). A escovação ao longo de 7 dias apresentou o menor valor de ângulo de contato (p ≥ 0,05). As imagens do MCVL mostraram alterações morfológicas para todos os grupos. Conclusão: Os dentifrícios dessensibilizantes não interferiram na molhabilidade da dentina erodida após escovação ao longo de 7 ou 21 dias. A escovação com qualquer um dos dentifrícios ao longo de 21 dias promoveu a abertura dos túbulos dentinários (AU)

Molhabilidade de um cimento endodôntico à base de resina epóxi na dentina tratada com diferentes protocolos de quelação / Wettability of an epoxy resin-based root canal sealer on dentin treated with different chelating protocols

Objetivo: Avaliar a molhabilidade do cimento AH Plus em contato com a dentina radicular após diferentes protocolos quelantes envolvendo ácido etidrônico (HEBP) e o EDTA. Métodos: Cinquenta e seis fatias de dentina radicular foram utilizadas e irrigadas com 5.25% de hipoclorito de sódio (NaOCl) ou com uma mistura de 5.25%NaOCl/18%HEBP para simular a irrigação durante o preparo químico-mecânico. As amostras irrigadas com NaOCl foram divididas em 5 grupos, de acordo com o agente quelante: G1- água destilada (AD); G2-17%EDTA; G3-17%EDTA+2.5%NaOCl; G4-18%HEBP; e G5-18%HEBP+2.5%NaOCl. As amostras irrigadas com a mistura de NaOCl/HEBP foram dividias em 2 grupos: G6-AD; G7-NaOCl/HEBP+2.5%- NaOCl. Todos os protocolos receberam irrigação de AD entre as substâncias irrigadoras e como lavagem final. O goniômetro Rame-Hart foi utilizado para mesurar o ângulo de contato entre a superfície da dentina radicular e o cimento. O teste estatístico Kruskal-Wallis e Dunn foram aplicados (p<0.05). Resultados: Os grupos onde a smear layer foi removida apresentaram menor ângulo de contato (p<0.05), com exceção do G7. O G6 apresentou o menor ângulo de contato do AH Plus, entretanto, a irrigação final com NaOCl (G7) aumentou significativamente o ângulo de contato. G2 e G4 apresentaram comportamento similar e a irrigação final com NaOCL (G3 e G4) não modificou a molhabilidade da dentina. Conclusão: O tratamento da dentina radicular com a mistura NaOCl/HEBP, quando usada como irrigante, conferiu boa molhabilidade desta superfície ao cimento AH Plus(AU).

Evaluate the wettability of AH Plus in contact with root dentin after different chelating protocols involving etidronic acid (HEBP) and EDTA. Material and Methods: Fifty six human polished root dentin slices were used. They were irrigated with 5.25% sodium hypochlorite (NaOCl) or a mixture of 5.25%NaOCl/18%HEBP to simulate irrigation during chemomechanical preparation. The specimens irrigated with NaOCl were divided into 5 groups regarding chelating agents: G1-destiled water (DW); G2- 17%EDTA; G3-17%EDTA+2.5%NaOCl; G4-18%HEBP; and G5-18%HEBP+2.5%NaOCl. The specimens irrigated with the mixture NaOCl/HEBP were divided into 2 groups: G6-DW; G7-NaOCl/HEBP+2.5%NaOCl. All protocols received irrigation with DW between irrigants and as final rinse. Rame-Hart goniometer was used to measure the contact angle between the dentin surfaces and the sealer. Kruskal-Wallis and Dunn tests were applied (p<0.05). Results: Groups in which the smear layer was removed showed a lower contact angle (p<0.05), except for G7. The G6 showed the lowest contact angle of AH Plus, but the NaOCl final irrigation (G7) increased the angle. G2 and G4 have similar behaviour and final irrigation with NaOCl (G3 and G5) did not change wettability when these chelators were used. Conclusions: The mixture NaOCl/HEBP showed good effect on the wettability of sealer on to the root canal dentine, when used as main irrigant (AU).

Effect of ethanol-conditioned dentine on sealer penetration into dentinal tubules: a confocal microscopy study

Aim: The aim of this study was to evaluate the effect of ethanol-conditioned dentin on endodontic sealer penetration into dentinal tubules by confocal laser scanning microscopy (CLSM). Methods: Forty human maxillary anterior teeth were instrumented and divided into four groups (n = 10) according to the drying methods: 1) wet: vacuum only, 2) paper points: vacuum + absorbent paper points, (3) 70% ethanol: 70% ethanol (1 min) + vacuum + absorbent paper points, and (4) 100% ethanol: 100% ethanol (1 min) + vacuum + absorbent paper points. All root canals were filled with resin-based endodontic sealer. Four sections from each third (cervical, middle, and apical) were examined by CLSM. Root canal wall perimeter infiltrated by sealer, maximum depth of sealer penetration, percentage of penetrated area, and fluorescence intensity of rhodamine B were measured. Statistical analysis was performed by analysis of variance and Tukey's tests (α = 0.05). Results: No statistical difference was found when percentage of root canal wall coverage infiltrated by sealer were compared. The groups in which ethanol solutions were used presented greater depth of sealer penetration, higher percentage of penetrated area, and higher fluorescence intensity of rhodamine B (p< 0.05) when compared with the wet and paper point groups. Overall, 100% ethanol produced better results than 70% ethanol, except for rhodamine B intensity (cervical third). In addition, the absorbent paper points drying method behaved better than did vacuum only group, except for rhodamine B intensity (apical third). Conclusion: Ethanol-conditioned dentin improved the penetration of resin-based sealer into dentinal tubules, especially at the concentration of 100%

Research progress on the effect of surface charge of biomaterials on bone formation / 生物医学工程学杂志

With the continuous progress of materials science and biology, the significance of biomaterials with dual characteristics of materials science and biology is keeping on increasing. Nowadays, more and more biomaterials are being used in tissue engineering, pharmaceutical engineering and regenerative medicine. In repairing bone defects caused by trauma, tumor invasion, congenital malformation and other factors, a variety of biomaterials have emerged with different characteristics, such as surface charge, surface wettability, surface composition, immune regulation and so on, leading to significant differences in repair effects. This paper mainly discusses the influence of surface charge of biomaterials on bone formation and the methods of introducing surface charge, aiming to promote bone formation by changing the charge distribution on the surface of the biomaterials to serve the clinical treatment better.

Investigating key influencing factors of low wettability of Indigo Naturalis based on component “knockout method” combined with surface property analysis / 中草药

Objective: To explore the key factors affecting the low wettability of Indigo Naturalis by using “knockout” method combined with surface element analysis, so as to provide scientific basis for regulating and changing the wettability of Indigo Naturalis. Methods: Using N,N-dimethylformamide as solvent, six Indigo Naturalis powders were prepared by ultrasonic extraction for 0-5 times, 30 min for each time, filtration and drying process. The contents of indigo and indirubin in six kinds of Indigo Naturalis were determined by HPLC. The contact angle, surface free energy and its components, particle size, surface morphology, surface element analysis and infrared spectroscopy were determined. The relationship between the content of organic matter and wettability of Indigo Naturalis was discussed by correlation analysis. Results: With the increase of extraction times, the content of indigo decreased from 3.320% to 0.112%, the content of indirubin decreased from 0.120% to 0.006%, the contact angle in pure water decreased from 53.56 degrees to 34.84 degrees, the polar component of surface free energy increased from 24.880 to 38.701 mJ/m2, the non-polar component changed little, and the total surface free energy increased from 46.523 to 62.240 mJ/m2. Scanning electron microscopy (SEM) showed that the particulate matter on the surface of Indigo Naturalis was gradually disappeared, and the surface became smooth; Mapping scanning by energy spectrometer showed that N element was gradually decreased, Ca and Si element were increased slightly; Particle size distribution and infrared spectrum changed little; Correlation analysis showed that the content of indigo, indigo and indirubin was positively correlated with the contact angle, and the higher the content, the worse the wettability. Conclusion: The contact angle, polar component of surface free energy and total surface free energy of Indigo Natural was significantly increased after knockout, and the wettability was increased. Organic substances adhering to the surface of Indigo Naturalis were the key factors leading to its low wettability. To improve the hydrophilicity of Indigo Naturalis by powder surface modification technology, it is necessary to focus on organic substances.

Effect of root canal irrigants on the bond strength between resin sealants and dentin / 口腔疾病防治

@#When the root canal is filled, the use of the adhesive resin-based sealant to form a strong bond with the dentin reduces microleakage of the apex, enhances the bending resistance of the tooth, and resists the mechanical damage of the pile preparation, thus improving the success rate of root canal treatment. However, during root canal treatment, the use of a rinsing agent may change the tissue structure of the dentin and the wettability of the dentin, thereby affecting the bonding strength between the resin sealing agent and the dentin. In this paper, the effects of a traditional root canal irrigant and several new rinsing agents on the bonding strength of resin sealant and dentin are reviewed. The results show that the traditional root canal rinsing agent NaClO is reduced as the final rinsing agent. The bonding strength of resin sealant to dentin; EDTA affects the biomechanical properties of root dentin, and the removal efficiency is low, which will affect the bond strength between the resin sealant and dentin. EDTA combined with NaClO as a final rinsing agent can improve the bonding strength. Chlorhexidine can also increase the bonding strength between the blocking agent and dentin and can be used as the final rinsing agent. The new rinsing agent MTAD has a negative impact on the resin sealing agent and dentin bond strength. QMix and maleic acid remove smear efficiency with dentin bond strengths greater than or equal to EDTA and can replace EDTA as the final rinse.

The effects of saline soaking on the removal torque of titanium implants in rabbit tibia after 10 days / 대한치과보철학회지

PURPOSE: The aim of this study was to confirm if Laser-treated implants were soaked in 0.9% NaCl solution for 2 weeks could increase the surface hydrophilicity, and the Remoal Torque of each implant that inserted in rabbit tibia for initial healing period of 10 days. MATERIALS AND METHODS: Twenty machined titanium surface screws were produced with a diameter 3 mm, length 8 mm. Ten screws had their surface treated with a laser only (laser treated group), and the other 10 were soaked in saline for 2 weeks after surface treatment with a laser (laser treated + saline soaked group). Implants were inserted in rabbit tibia (ten adult New Zealand white rabbits), and the RTQ of each implant was measured after 10 days. The wettability among implants was compared by measuring the contact angle. Surface composition and surface topography were analyzed. RESULTS: After 10 days, the laser treat + soaking group implants had a significantly higher mean RTQ than the laser treated implants (P = .002, < .05). There were no significant morphological differences between groups, and no remarkable differences were found between the two groups in the SEM analysis. CONCLUSION: Saline soaking implants is expected to produce excellent RTQ and surface analysis results.

Impacto de um método de polimento adicional em propriedades físicas, micromorfológicas e microtopográficas de compósitos convencionais e Bulk Fill / Impact of an additional polishing method on physical, micromorphological and microtopographical properties of conventional and Bulk Fill composites

O objetivo deste trabalho foi avaliar a rugosidade superficial, a molhabilidade, a disposição em profundidade das partículas de carga, o mapeamento de elementos químicos, a microtopografia em 3D e a micromorfologia de compósitos convencionais e bulk fill após polimento adicional. Éspécimes foram preparados de cada compósito testado, sendo quatro do tipo bulk fill (Filtek Bulk, Fill Tetric N-Ceram Bulk Fill, Opus Bulk Fill e X-tra Fil) e quatro convencionais (Filtek Z250 XT, Grandioso, Tetric NCeram, Vittra APS), de acordo com três técnicas de acabamento/polimento/polimento adicional (n = 10): sem acabamento e polimento, acabamento e polimento com borrachas abrasivas (Astropol), acabamento e polimento com Astropol mais polimento adicional com escova de carbeto de silício. A rugosidade superficial (Ra) e o ângulo de contato foram medidos usando-se um perfilômetro e goniômetro adaptado, respectivamente. A microtopografia 3D foi avaliada utilizando microscopia de força atômica (MFA), enquanto a micromorfologia e a disposição em profundidade das partículas de carga, através da microscopia eletrônica de varredura (MEV). O mapeamento de elementos químicos foi avaliado por meio de Espectroscopia por energia dispersiva de raio-X (EDS). A rugosidade e o ângulo de contato foram analisados pelo ANOVA-dois fatores e teste de Tukey (p <0,05); os demais dados foram analisados descritivamente. A disposição das partículas de carga em profundidade de todas as resinas envolvidas neste estudo apresentou uma camada superficial rica em matriz orgânica e uma camada subsuperficial rica em partículas de dimensões mais diminutas. O polimento adicional: diminuiu a rugosidade superficial das resinas Filtek Bulk Fill, Vittra APS, Tetric N-ceram Bulk Fill e X-tra fil; aumentou o valor do ângulo de contato da X-tra Fil e diminuiu da Filtek Z250 XT. Nas análises para microtopografia em 3D e a micromorfologia, superfícies mais lisas e uniformes foram observadas em todas as resinas. Os elementos: carbono (C), cxigênio (O), silício (Si), zircônia (Zr) e alumínio (Al) foram presentes em todas as resinas compostas. O bário (Ba) foi ausente na Filtek Z250 XT, Filtek Bulk Fil e Vittra APS. O carbono foi predominante em todas as resinas. Após polimento adicional, houve um aumento na detecção de oxigênio para todas as resinas, exceto para Tetric N-Ceram e Xtra Fil e uma diminuição de carbono, exceto para a Tetric N-Ceram Bulk Fil. O silício diminuiu apenas nas resinas Z250 XT, Tetric N-Ceram e Tetric N-Ceram Bulk Fill. A zircônia diminuiu para a Tetric N-Ceram Bulk Fill e o alumínio para Z250 XT e Tetric N-Ceram Bulk Fill. O bário aumentou para Opus Bulk fill e X-tra Fil. O titânio foi ausente para todas as resinas. Portanto, o polimento adicional melhorou as propriedades de superfície das resinas estudadas (AU).

The objective of this study was to evaluate the surface roughness, wettability, the depth distribution of the charge particles, the mapping of chemical elements, the 3D microtopography and the micromorphology of the composites of the conventional and bulk fill after additional polishing. The specimens were prepared from each of the composites tested, four of them being bulk fillers (Filtek Bulk Fill Tetric N-Ceram Bulk Fill Opus Bulk Fill X-tra Fil) and four conventional ones (Filtek Z250 XT, Grandioso, Tetric N-Ceram, Vittra APS ), according to three additional finishing / polishing / polishing techniques (n = 10): without finishing and polishing, finishing and polishing with abrasive rubbers (Astropol), finishing and polishing with Astropol plus additional polishing with silicon carbide brush. The surface roughness (Ra) and contact angles were measured using a profilometer and adapted goniometer, respectively. The 3D microtopography was evaluated using atomic force microscopy (AFM); while the micromorphology and the in-depth arrangement of the charge particles by scanning electron microscopy (SEM). The mapping of chemical elements was evaluated by means of X-ray Dispersive Energy Spectroscopy (EDS). The roughness and the contact angle were analyzed by ANOVA- two factors and Tukey test (p <0.05); the other data were analyzed descriptively. The arrangement of the in-depth charge particles of all the resins involved in this study had an organic matrix rich surface layer and a particulate rich subsurface layer of smaller dimensions. Addicional polishing: reduced surface roughness of Filtek Bulk Fill resins, Vittra APS, Tetric N-ceram Bulk Fill and X-trafil resins; increased the contact angle value of the X-tra Fil and decreased the Filtek Z250 XT. In the analyzes for 3D microtopography and micromorphology, smoother and more uniform surfaces were observed in all a resins. The elements: carbon (C), oxygen (O), silicon (Si), zirconia (Zr) and aluminum (Al) were present in all composite resins. Barium (Ba) was absent on Filtek Z250 XT, Filtek Bulk Fil and Vittra APS. Carbon was predominant in all resins. After additional polishing, there was an increase in oxygen detection for all resins except for Tetric N-Ceram and X-tra Fil and a decrease in carbon except for Tetric N-Ceram Bulk Fil. Silicon decreased only in the Z250 XT, Tetric N-Ceram and Tetric NCeram Bulk Fill resins. Zirconia decreased for Tetric N-Ceram Bulk Fill and aluminum for Z250 XT and Tetric N-Ceram Bulk Fill. Barium increased for Opus Bulk fill and X-tra Fil. Titanium was absent for all resins. Therefore, additional polishing improved the surface properties of the resins studied (AU).

Influence of ethanol on dentin roughness, surface free energy, and interaction between AH Plus and root dentin

Abstract This study aimed to evaluate the influence of different ethanol concentrations on dentin roughness, surface free energy, and contact angle between AH Plus and the root canal dentin. One hundred human maxillary anterior teeth were split longitudinally and 200 dentin specimens were polished to make the surface flatter and smoother. An acrylic bar was positioned between two dentin specimens and impression material was added to create a block, simulating an instrumented root canal space. Specimens were removed from the mold and cleaned in an ultrasonic bath for 10 min. Thereafter, dentin specimens were divided into four groups (n = 50) according to the drying methods used: a) wet: vacuum only, b) paper points: vacuum + absorbent paper points, c) 70% alcohol: 70% alcohol (1 min) + vacuum + absorbent paper points, and d) 100% alcohol: 100% alcohol (1 min) + vacuum + absorbent paper points. A rugosimeter and a goniometer were used to verify the roughness (Ra) and to measure the surface free energy and the contact angle between the AH Plus sealer and the root canal dentin. ANOVA and Tukey tests (α = 0.05) were used for statistical analysis. The 70% and 100% ethanol groups showed significantly decreased roughness as well as increased surface free energy in the root canal dentin when compared to the wet and paper point groups. In addition, ethanol significantly reduced the contact angle between the AH Plus sealer and the root canal dentin. Ethanol solutions (70% and 100%) provide better wettability of AH Plus sealer on dentin surfaces.

Influences of Surfactants on Contact Angle of Pharmaceutical Excipients / 中国药师

Objective:To investigate the effect of surfactants on contact angle of pharmaceutical excipients and further study the effect of surfactants at different concentrations on the wettability of excipients and the effect of of surfactants and excipients at different proportions on the wettability of tablets. Methods:Different kinds of excipients were selected for tabletting,and surfactant solutions at different concentrations were prepared. The contact angle of the solutions on the surface of the tablets was measured by a contact angle tester. Results:The contact angle between the surfactants below the critical micelle concentrations and the tablets was the smallest and the wettability was the best. The change of the contact angle on the tablets with hydrophilic materials was less than that with hydropho-bic ones for most of the surfactants at the same concentration. Conclusion:After the addition of surfactants,the contact angle of excip-ient tablets significantly decreases, however, the contact angle will be stable after the amount of surfactants reaches a certain ratio, which shows significant reference value for tablet formula design.

The effects of plasma treatment on the wettability and adhesion properties of the surface of aged denture base resin / 实用口腔医学杂志

Objective:To investigate the effects of plasma treatment on the surface element,wettability and adhesion properties of aged denture base resin.Methods:42 pieces of 10 mm × 10 mm × 1 mm and 100 cubes of 8 mm × 10 mm × 30 mm polymethyl methacrylate specimens were prepared and thermocycled at 5-55 ℃ for 5 000 cycles.40 pieces were used for surface contact angle measurement and 2 for X-ray photoelectron spectroscopy analysis.The 100 cubes were randomly divided into 5 groups:Control(A) and 4 experimental groups in which the samples were exposed to plasma for 1 min (B),2 min (C),3 min (D) and 4 min (E) (n =20) respectively.After plasma treatment,silicone-based soft liner (3 mm) was packed against 2 resin cubes.Thus,50 tensile test specimens were obtained(n =10),and the tensile bond strength was tested by a universal testing machine.Results:The contact angle (°) of group A,B,C,D,E was 63.60 ± 10.81,46.79 ± 5.08,44.13 ± 4.17,40.11 ± 6.01 and 41.03 ± 8.61 respectively (A vs B,C,D or E,P ＜ 0.05).After plasma treatment,the contents of O =C-O and C-O in the samples were increased from 14.17％ and 20.58％ to 18.32％ and 29.32％,respectively.The tensile bond strength(MPa) of group A,B,C,D and E was 0.884 ±0.130,1.281 ±0.086,1.419 ±0.103,1.871 ± 0.248 and 1.904 ± 0.223 respectively (A vs B,C,D or E,P ＜ 0.05;B or C vs D or E,P ＜ 0.05;B vs C,P ＞ 0.05;D vs E,P ＞ 0.05).Conclusion:Plasma treatment can improve the wettability and adhesion properties of aged denture base resin.

Efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl / Effect of oxygen plasma on dentin exposed to NaOCl

Introdução: O tratamento de plasma é uma tecnologia eficaz que pode manter as propriedades internas dos materiais inalteradas após o tratamento, modificando apenas a superfície. Objetivo: Avaliar o efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl 6%. Material e método: Foram utilizados 60 incisivos bovinos. A coroa foi removida, a raiz foi dividida e as faces planificadas, totalizando 120 segmentos referentes ao terço cervical. As amostras foram divididas em dois grupos: controle (imersa em NaOCl 6%, lavada com água destilada, seca, imersa em EDTA 17%, lavada e seca) e plasma de oxigênio (após tratamento descrito no grupo controle, plasma de oxigênio foi aplicado por 30 s). As amostras foram avaliadas qualitativamente em relação à topografia por microscopia eletrônica de varredura, utilizando-se microfotografias com ampliação de 1.000×. O goniômetro Ramé-hart foi utilizado para a mensuração do ângulo de contato entre as superfícies e as seguintes soluções foram utilizadas: água, etilenoglicol e di-iodometano. Em seguida, a energia de superfície, representada pelas componentes polar e dispersiva, foi calculada. Avaliou-se também o escoamento dos cimentos Pulp Canal Sealer EWT (PCS) e Real Sal SE (RS) na superfície dentinária. Os dados foram analisados estatisticamente utilizando os testes Kruskal-Wallis e Mann-Whitney U (p<0,05). Resultado: O tratamento com plasma levou à formação de uma camada semelhante à smear layer na superfície dentinária. Este tratamento levou a um aumento da energia de superfície e da componente polar, favorecendo a hidrofilicidade da superfície. Entretanto, desfavoreceu o escoamento do cimento PCS e não influenciou no escoamento do cimento RS. Conclusão: O plasma de oxigênio ocasionou mudanças topográficas na superfície dentinária, favorecendo a hidrofilicidade desta. Contudo, não favoreceu o escoamento dos cimentos endodônticos na dentina.

Introduction: Plasma treatment is an effective technology since the internal properties of the material is kept unchanged after treatment, modifying only the surface. Objective: To evaluate the effect of oxygen plasma on dentin previously exposed to 6% NaOCl. Material and method: 60 bovine incisors were used. The crown was removed, the root splited and the faces planned amounting 120 segments related to the cervical third. The samples were divided into 2 groups, control (immersed in 6% NaOCl, washed with distilled water, dried, immersed in 17% EDTA, washed and dried) and oxygen plasma (after treatment described in the control group, oxygen plasma was applied for 30s). The samples were evaluated qualitatively in relation to topography by scanning electron microscopy using photomicrographs at 1000× of magnification. The Ramé-hart goniometer was used to measure the contact angle between the surfaces and the following solutions: water, ethyleneglycol, and diiodomethane. Then, surface energy, polar and dispersive components, was calculated. Additionally, it was evaluated the flow of Pulp Canal Sealer EWT (PCS) and Real Salt SE (RS) sealers on dentin surface. Data were statistically analyzed using Kruskal-Wallis e Mann-Whitney U (p<0.05). Result: Plasma treatment caused topographical changes on dentin surface. This treatment led to an increase in surface energy and polar component, favoring the hydrophilicity of the surface. However, it disfavors the wettability of PCS and did not influence the RS wettability. Conclusion: The oxygen plasma caused topographical changes on dentin surface, favoring its hydrophilicity. However, it did not favor the sealers wettability on dentin.

Effect of Argon Plasma on Root Dentin after Use of 6% NaOCl

Abstract The aim of this study was to evaluate the effect of argon plasma on dentin surface after use of 6% NaOCl. Sixty bovine incisors had their crowns removed, the roots split, and the segments planed. One hundred twenty segments of the cervical third were used. The samples were divided in two groups (n=60): Control group: immersed in 6% NaOCl, washed, dried and then immersed in 17% EDTA, washed and dried and Argon group: after treatment described for the Control group, non-thermal argon plasma was applied for 30 s. Ten samples were evaluated by scanning electron microscopy in each group. Other ten samples were analyzed by Fourier transform infrared spectroscopy (FTIR). Thirty samples were analyzed with a goniometer to measure the contact angle between the dentin surfaces and solutions, to determine the surface free energy. The last ten samples were used to evaluate the wettability of AH Plus sealer. Data were statistically analyzed using Kruskal Wallis and Mann-Whitney tests (p<0.05). The results of this study showed that argon plasma did not modify the surface topography. FTIR analysis showed chemical modifications after plasma treatment. Argon plasma increased the surface free energy of dentin and AH Plus wettability. In conclusion, argon plasma treatment modified chemically the dentin surface. This treatment increased the surface free energy and wettability of an epoxy resin root canal sealer, favoring its bonding to dentin surfaces.

Resumo O objetivo do presente estudo foi avaliar o efeito do plasma de argônio na superfície dentinária após o uso de NaOCl 6%. As coroas de 60 incisivos bovinos foram removidas, as raízes clivadas e os segmentos planificados. Cento e vinte segmentos referentes ao terço cervical foram utilizados. As amostras foram divididas em dois grupos (n=60): Grupo Controle: imersos em NaOCl 6%, lavados, secos, imersos em EDTA 17%, lavados e secos e Grupo Argônio: após o tratamento descrito no grupo controle, foi aplicado plasma de argônio não térmico por 30 s. Em cada grupo, 10 amostras foram avaliadas por microscopia eletrônica de varredura. Outras dez amostras foram analisadas por espectroscopia no infravermelho por transformada de Fourier (FTIR). Trinta amostras foram analisadas com um goniômetro para medir o ângulo de contato entre a superfície dentinária e as soluções e determinar a energia livre de superfície. As últimas dez amostras foram utilizadas para avaliar a molhabilidade do cimento AH Plus. Os dados foram analisados estatisticamente usando os testes de Kruskal Wallis e Mann-Whitney (p<0,05). Os resultados do estudo mostraram que o plasma de argônio não modificou a topografia de superfície. A análise por FTIR mostrou modificações químicas após o tratamento de plasma. O plasma de argônio aumentou a energia livre da superfície dentinária e a molhabilidade do cimento AH Plus. Conclusão, o tratamento com plasma de argônio modificou quimicamente a superfície dentinária. Este tratamento aumentou a energia livre de superfície e a molhabilidade de um cimento endodôntico à base de resina epóxi, favorecendo as características adesivas da superfície dentinária.

Drying protocol influence on the bond strength and apical sealing of three different endodontic sealers

Abstract The aim of this study was to evaluate the influence of drying protocols (DP) on the apical sealing (AS) and on the bond strength (BS) of teeth filled with different sealers. The root canals of one hundred and fifty-six roots of maxillary canines were prepared with Reciproc rotary files (R50). The teeth were randomly divided into four groups (n = 39), according to the DP: GI-paper points; GII-70% isopropyl alcohol + aspiration with NaviTip points; GIII-95% ethanol + paper points; GIV-EndoVac + paper points. Each group was divided into subgroups, according to the sealer used: AH Plus, Sealapex and MTA Fillapex, using a single-cone technique. Evaluation of AS and BS was performed with fluid filtration (FF) and push-out (PO) methods, respectively. The PO test consisted of sectioning the roots, and subjecting a single slice from each third to testing and analysis for failure type. The data was submitted to two-way and three-way variance analysis (ANOVA) and Tukey (α = 5%). The AS showed no drying protocol influence. The FF results revealed a statistically significant difference between MTA and Sealapex (p < 0.05) sealers. The BS test values showed that there was no statistical significant difference among the canal thirds (p > 0.05), but that there was such a difference among the sealers (p < 0.05), among the protocols (p < 0.05), and in the interaction between sealers and protocols (p < 0.05). AH Plus revealed the highest BS values among the sealers; the highest BS results for the sealers occurred with the specimens used with isopropyl alcohol, compared with ethanol and EndoVac.

Influence of Implant Surfaces on Osseointegration: A Histomorphometric and Implant Stability Study in Rabbits

Abstract: The aim of this study was to evaluate the stability and osseointegration of implant with different wettability using resonance frequency analysis (RFA) and histomorphometric analysis (bone implant contact, BIC; and bone area fraction occupied, BAFO) after 2 and 4 weeks in rabbit tibiae. Thirty-two Morse taper implants (length 7 mm, diameter 3.5 mm) were divided according to surface characteristics (n=8): Neo, sandblasted and dual acid-etched; and Aq, sandblasted followed by dual acid-etched and maintained in an isotonic solution of 0.9% sodium chloride. Sixteen New Zealand rabbits were used. Two implants of each group were installed in the right and left tibiae according to the experimental periods. The RFA (Ostell(r)) was obtained immediately and after the sacrifice (2 and 4 weeks). The bone/implant blocks were processed for histomorphometric analysis. Data were analyzed using two-way ANOVA followed by Tukey's test and Pearson's correlation for ISQ, BIC and BAFO parameters (p=0.05). No significant effect of implant, period of evaluation or interaction between implant and period of evaluation was found for BIC and BAFO values (p>0.05). Only period of evaluation had significant effect for RFA values at 4 weeks (p=0.001), and at 2 weeks (p<0.001). RFA values were significantly higher at the final period of evaluation compared with those obtained at early periods. There was a significant correlation between BIC values and BAFO values (p=0.009). Both implant surfaces, Aq and Neo, were able to produce similar implant bone integration when normal cortical bone instrumentation was performed.

Resumo: O objetivo deste estudo foi avaliar a estabilidade e osseointegração de implantes com superfícies com diferentes molhabilidades empregando análise de frequência de ressonância (RFA) e histomorfometria (contato implante ósseo, BIC, e fração de área óssea ocupada, BAFO), nos períodos de 2 e 4 semanas em tíbias de coelhos. Trinta e dois implantes cone Morse (comprimento 7mm, diâmetro 3,5 mm), foram divididos de acordo com tratamento de superfície (n = 8): Neo, superfície jateada e condicionada com ácido; e Aq, superfície jateada e condicionada com ácido e mantida em solução isotônica de cloreto de sódio a 0,9%. Dezesseis coelhos tipo Nova Zelândia foram utilizados neste estudo. Dois implantes de cada grupo foram instalados nas tíbias direita e esquerda de acordo com os períodos experimentais. Os valores de RFA (Ostell(r)) foram obtidos imediatamente e após o sacrifício (2 e 4 semanas). Os blocos ósseos/implante foram processados para análise histomorfométrica. Os dados foram analisados usando ANOVA fatorial seguido pelo teste de Tukey e também por meio de correlação de Pearson para os fatores RFA, BIC e BAFO (P=0,05). Nenhum efeito significativo dos fatores tipo de implante, período de avaliação e da interação entre o tipo de implante e período de avaliação foram observados para os valores de BIC e BAFO. Apenas o período de avaliação resultou em efeito significativo para valores RFA após 2 semanas (p=0,001), e 4 semanas (p<0,001). Os valores de RFA valores foram significativamente mais elevados no final do período de avaliação em comparação com os obtidos em inicialmente. Houve correlação significativa entre os valores BIC e BAFO (p=0,009). Ambas as superfícies de implantes, Aq e Neo, são capazes de produzir adequada integração osso/implante em condição normal de instrumentação do osso cortical.

O papel da superfície moderadamente rugosa e quimicamente modificada em um protocolo de carga precoce: uma revisão de literatura / The role of a moderately rough and chemically modified implant surface in an early loading protocol: a literature review

Realizar uma revisão de literatura, com base nas evidências científicas atualmente disponíveis, a respeito dos períodos iniciais do reparo ósseo em torno de implantes com superfície moderadamente rugosa e quimicamente modificada (MRQM). Para a revisão da literatura, foi realizada uma pesquisa eletrônica via PubMed, utilizando, para a seleção dos artigos, uma combinação das palavras-chave ‘osseointegration’, ‘bone-to-implant contact’, ‘wettability’, ‘chemically modified surface’ e ‘bone healing’. Foram considerados estudos experimentais in vitro, em modelos animais e em humanos, abrangendo as características físico-químicas, mecanismos biológicos e eventos histológicos iniciais relacionados à superfície MRQM. Estudos experimentais reportam uma maior aposição óssea e ancoragem à superfície quimicamente modificada, nos estágios iniciais do reparo ósseo, em modelos animais. Esses resultados experimentais foram validados por estudos clínicos prospectivos, estudos de mensuração da estabilidade do implante com análise de frequência de ressonância (RFA), perfis de expressão gênica e histológicos temporais em modelos humanos. Dentro das limitações desse estudo da superfície MRQM, é possível sugerir que a alta energia da superfície e molhabilidade aumentada influenciam positivamente na formação óssea nos períodos iniciais do reparo ósseo...

The aim of this study was to accomplish a literature review, based on currently available evidence, about the early periods of bone integration around endosseous implants with moderately rough and chemically modified surface (MRCM). The review was performed through an electronic survey via PubMed, using a combination of keywords, including: osseointegration, bone-to-implant contact, wettability, chemically modified surface and bone healing. Experimental in vitro studies, in animal models and in humans, covering physicochemical characteristics, biological mechanisms and initial histological events related to MRCM implant surface were considered. Experimental studies report higher bone apposition and better bone anchorage to MRCM surfaces during early stages of bone healing in animal models. These experimental results were validated by prospective clinical studies, studies measuring implant stability with resonance frequency analysis, gene expression profiles and temporal histological studies in human models. Within the limitations of this MRCM surface study, it is suggested that high surface energy and increased wettability positively influence bone formation in the initial periods of bone repair...

Early osseointegration driven by the surface chemistry and wettability of dental implants

Objective The objective of this study was to investigate the impact of two different commercially available dental implants on osseointegration. The surfaces were sandblasting and acid etching (Group 1) and sandblasting and acid etching, then maintained in an isotonic solution of 0.9% sodium chloride (Group 2). Material and Methods X-ray photoelectron spectroscopy (XPS) was employed for surface chemistry analysis. Surface morphology and topography was investigated by scanning electron microscopy (SEM) and confocal microscopy (CM), respectively. Contact angle analysis (CAA) was employed for wetting evaluation. Bone-implant-contact (BIC) and bone area fraction occupied (BAFO) analysis were performed on thin sections (30 μm) 14 and 28 days after the installation of 10 implants from each group (n=20) in rabbits' tibias. Statistical analysis was performed by ANOVA at the 95% level of significance considering implantation time and implant surface as independent variables. Results Group 2 showed 3-fold less carbon on the surface and a markedly enhanced hydrophilicity compared to Group 1 but a similar surface roughness (p>0.05). BIC and BAFO levels in Group 2 at 14 days were similar to those in Group 1 at 28 days. After 28 days of installation, BIC and BAFO measurements of Group 2 were approximately 1.5-fold greater than in Group 1 (p<0.05). Conclusion The surface chemistry and wettability implants of Group 2 accelerate osseointegration and increase the area of the bone-to-implant interface when compared to those of Group 1. .

Caracterização do insumo ibuprofeno e a correlação com propriedades de dissolução e de fluxo / Characterization of ibuprofen raw material and correlation with dissolution and flow properties

Ibuprofen is a moderately active non-steroidal anti-inflammatorydrug, derived from β-phenylpropionic acid. Its analgesic action, which is related to its anti-inflammatoryproperties, is due to a decrease in the production of enzymes cyclo-oxygenase-1 (COX-1) and cyclo-oxygenase-2 (COX-2). Ibuprofen exhibits distinct morphologies when crystallized under different conditions. In this study, the characteristics of the ibuprofen raw material and their impact on drug dissolution and processing properties were analyzed. Samples of raw ibuprofen from 3 different manufacturers were characterized by a variety of techniques. The analysis confirmed that all 3 samples exhibited the same crystalline form; thus, polymorphism could be discarded as one of the causes of any variation in performance of the drug. The results showed that the physical characteristics of each sample influenced its flow and dissolution properties. In fact, there was a detectable variation in the physical characteristics of the drug among the 3 different manufacturers. This demonstrates the importance of testing the characteristics of the drug raw material in order to correlate them with its performance in processing and eventual use, enabling pharmacotechnical improvement and development...

O ibuprofeno é um agente anti-inflamatório não esteróide, derivado do ácido fenilpropiônico que possui atividade anti-inflamatória de ação moderada. Sua ação analgésica está relacionada às propriedades anti-inflamatórias devido à redução da produção da ciclooxigenase-1 (COX-1) e da ciclooxigenase-2 (COX-2). O ibuprofeno exibe diferentes morfologias quando cristalizado em diferentes solventes. Neste estudo, se avaliaram as características de matérias-primas do ibuprofeno e o impacto destas nas propriedades de dissolução e processamento. Foram avaliadas três matérias-primas do ibuprofeno de três diferentes fabricantes, utilizando variadas técnicas de caracterização. As análises confirmaram que todas apresentavam a mesma forma cristalina do ibuprofeno; assim, o polimorfismo foi descartado como uma das causas de influência na dissolução e no fluxo do fármaco. Os resultados mostraram que características físicas da matéria-prima ibuprofeno tiveram impacto nas propriedades de fluxo e dissolução e que existe uma variabilidade das características físicas do fármaco entre diferentes fabricantes. Isto mostra a importância da avaliação de características da matéria-prima para correlacioná-las com propriedades de desempenho, possibilitando o desenvolvimento e melhoramento farmacotécnico...

Dynamics of the interaction between body fluid and Ti cp: the influence of surface functionalization in the first stages of osseointegration

INTRODUCTION: Regenerative therapies using biomaterials require accurate information on interactions between the implanted material and the human body. To improve the process of bone regeneration it is necessary to obtain a better understanding of the influence of the surfaces on the early stages of osseointegration. This work aims to investigate the dynamic interaction between simulated body fluid (SBF) and titanium surfaces (Ti cp) immediately after their first contact. METHODS: Ti cp samples were passed through physicochemical treatments after immersion in acid solution, alkaline solution and solutions containing TiO2 and Ca2+, to obtain three different surfaces. These were characterized by electron microscopy and free energy estimates. The evaluation of the interaction with SBF was performed by measuring the dynamic contact angles after contacting the surfaces. RESULTS: The effects of SBF wettability were more significant on surfaces according to high energy estimates. A comparative analysis of the three types of surfaces showed that fluid spreading was greater in samples with greater polar components, indicating that the surface nature influences interactions in the early stages of osseointegration. CONCLUSION: The results indicate the influence of polar interactions in the dynamic wettability of the SBF. It is possible that these interactions can also influence cellular viability on surfaces. Based on these results, new experiments are being designed to improve the presented methodology as a tool for the evaluation of biomaterials without the need for in vivo experiments.