Avaliação dos Efeitos da Remoção da Resina Residual e do Polimento na Superfície do Esmalte após Descolagem do Braquete / Evaluation of the Effects of Residual Resin Removal and Polishing on the Enamel Surface after Bracket Debonding

Considerando o uso de brocas para remoção da resina residual após descolagem do braquete e a possibilidade de injúrias à superfície do esmalte após o uso dessas brocas, este trabalho teve como objetivo realizar um estudo experimental, para avaliar a variação do aspecto superficial do esmalte de forma qualitativa, por meio da avaliação com imagens topográficas do esmalte dentário, utilizando-se a Microscopia Eletrônica de Varredura (MEV), a qual permitiu ilustrar e avaliar a superfície do esmalte após a fase de polimento final, realizada por dois métodos: taça de borracha ou escova Robinson. Foram utilizados 25 dentes pré-molares humanos, obtidos a partir de exodontias em pacientes que procuraram voluntariamente o curso de Residência em Cirurgia da Clínica Odontológica Universitária da Universidade Estadual de Londrina. Os dentes foram divididos em quatro grupos: A, B, C e D, contendo 6 dentes cada, de acordo com as brocas utilizadas para a remoção do remanescente adesivo e o polimento escolhido, além de um dente como "controle". Foi avaliada a rugosidade superficial do esmalte após a remoção da resina e a superfície do esmalte após o polimento com as duas opções apresentadas. Os resultados mostraram que, por observação e inspeção, as brocas removeram a resina residual de todos os dentes, porém, causaram riscos e ranhuras, como evidenciado nas imagens em MEV. Concluiu-se que não houve diferença estatística entre os métodos de polimento e que ambos foram importantes para a redução das marcas abrasivas, proporcionando uma superfície mais lisa do esmalte.

Considering the use of specific burs to remove residual resin after bracket debonding and the possibility of injuries to the dental enamel after using these burs, this study aimed to verify the variation in the enamel surface appearance in a qualitative way and evaluation with topographic images of the dental enamel. The use of Scanning Electron Microscopy (SEM) allowed to illustrate and evaluate the enamel surface after the final polishing phase using two methods: rubber cup or Robinson brush. Twenty-five human premolar teeth were obtained from extractions in patients who voluntarily sought the Oral Maxillofacial Surgery Residency at the Dental School from the State University of Londrina; the teeth were divided into four groups A, B, C and D containing 6 teeth each according to the burs used to remove the remaining adhesive and the chosen polishing, in addition to one tooth as a "control". Dental enamel surface roughness was evaluated after resin removal and enamel surface after polishing with the two methods presented. The results showed that by observation and inspection, the burs removed residual resin from all teeth, however, caused scratches and grooves as evidenced in the SEM images. Based on the results, there was no statistical difference between the polishing methods, and both were important for the reduction of abrasive marks and provided a smoother enamel surface.

Effect of chemical or mechanical finishing/polishing and immersion in staining solutions on the roughness, microhardness, and color stability of CAD-CAM monolithic ceramics / Efeito do acabamento/polimento químico ou mecânico e imersão em soluções manchantes na rugosidade, microdureza e estabilidade da cor em cerâmicas monolíticas CAD-CAM

ABSTRACT During the manufacture of ceramic restorations there is an important step of finishing and polishing and the effects of different types of these procedures on the surface characteristics of ceramics are not known for sure. Aim: To evaluate the effects of various surface treatments and immersion in coloring substances on the roughness, microhardness, and color stability of CAD-CAM monolithic ceramics. Materials and Method: The ceramics used were lithium disilicate reinforced with zirconium dioxide (Suprinity), lithium disilicate (E.max) or leucite (Empress). They were subjected to two surface treatments: glazing (group G) (n=20) or mechanical polishing (group P) (n=20). Then they were divided into two subgroups (n=10) to be treated with the staining substance (coffee or water). Roughness, microhardness and color were measured before and after treatment. Data were subjected to analysis of variance and multiple comparisons were performed with Tukey tests at 5% significance level. Results: Roughness was lower in all tested ceramics after polishing than after glazing. Microhardness was the same for polished and glazed E.max, higher in glazed than polished Empress, and higher in polished than glazed Suprinity. Analysis of the effects of glazing and polishing on the individual ceramics showed that the ΔE2000 and ΔWID data of the E.max ceramic subjected to polishing showed greater change. Mechanical polishing is a good option for surface treatment of monolithic ceramics. Conclusion: Glazing was inferior and less satisfactory than polishing. Glazing generates changes that can lead to color instability.

RESUMO Durante a confecção de restaurações cerâmicas existe uma importante etapa dos procedimentos de acabamento e polimento. Os efeitos de diferentes tipos desses procedimentos nas características superficiais das cerâmicas não são conhecidos com certeza. Objetivo: Avaliar os efeitos de vários tratamentos de superfície e imersão em substâncias corantes na rugosidade, microdureza e estabilidade de cor de cerâmicas monolíticas CAD-CAM. Materiais e Métodos: As cerâmicas utilizadas foram dissilicato de lítio reforçado com dióxido de zircônio (Suprinity), dissilicato de lítio (E.max) ou leucita (Empress). Foram submetidos a dois tratamentos de superfície: glazeamento (grupo G) (n=20) ou polimento mecânico (grupo P) (n=20). Em seguida, foram divididos em dois subgrupos (n=10) para serem tratados com a substância corante (café ou água). Rugosidade, microdureza e cor foram medidas antes e após o tratamento. Os dados foram submetidos à análise de variância e as comparações múltiplas foram realizadas com testes de Tukey ao nível de 5% de significância. Resultados: A rugosidade foi menor em todas as cerâmicas testadas após o polimento do que após o glazeamento. A microdureza foi a mesma para o E.max polido e vidrado, maior no Empress vidrado do que no polido, e maior no Suprinity polido do que no vidrado. A análise dos efeitos do esmaltação e polimento nas cerâmicas individuais mostrou que os dados ΔE2000 e ΔWID da cerâmica E.max submetida ao polimento apresentaram maior alteração. O polimento mecânico é uma boa opção para o tratamento superficial de cerâmicas monolíticas. Conclusão: A aplicação do glazing foi inferior e menos satisfatório que o polimento, gerando alterações que podem levar à instabilidade da cor.

Efeito dos diferentes tipos de polimento sobre a rugosidade de superfície de uma resina acrílica comercial quimicamente ativada: estudo in vitro / Effect of different types of polishing on the surface roughness of a chemically activated commercial acrylic resin: an in vitro study

Objetivo: avaliar in vitro o polimento sobre resina acrílica quimicamente ativada (RAQA), por meio da rugosidade de superfície (Ra). Materiais e Método: Foram confeccionadas 40 amostras de RAQA, com dimensões de 10 a 10 x 2 mm, e foram divididas em quatro grupos (n=10): ausência do acabamento (AA); Ausência de polimento (AP); Polimento químico (PQ); Polimento com borrachas siliconadas + Escovas (PM). Os espécimes foram avaliados no quanto a rugosidade média (Ra) antes e após o envelhecimento em água destilada em uma estufa por 60 dias. Três medições de Ra (µm), na horizontal foram realizadas e calculada uma média para cada espécime. Os dados foram analisados de forma descritiva e inferencial, ANOVA de medidas repetidas e teste de Tukey com nível de significância de 5%. Resultados: Inicialmente, o grupo AA teve os menores valores de Ra e o grupo AP os maiores valores de rugosidade, com média e desvio padrão respectivamente 0,17 (±0,11) e 0,52 (±0,10). Após o envelhecimento, o grupo AA teve as menores médias e o grupo PQ os maiores valores de Ra, sendo 0,38 (±0,20) e 1,33 (±0,32), respectivamente. Os resultados evidenciaram diferença estatística significante quando as amostras foram submetidas ao acabamento com brocas. Conclusão: A RAQA necessita de polimento após acabamento com brocas, uma vez que a ausência de polimento comprometerá a lisura de superfície do material.(AU)

Objective: to evaluate in vitro polishing on chemically activated acrylic resin (RAQA), using surface roughness (Ra). Materials and Method: 40 RAQA samples were made, measuring 10 to 10 x 2 mm, and divided into four groups (n=10): absence of finishing (AA); Lack of polishing (AP); Chemical polishing (PQ); Polishing with silicone rubbers + Brushes (PM). The specimens were evaluated for their average roughness (Ra) before and after aging in distilled water in an oven for 60 days. Three horizontal Ra (µm) measurements were taken and an average was calculated for each specimen. Data were analyzed descriptively and inferentially, using repeated measures ANOVA and Tukey test with a significance level of 5%. Results: Initially, the AA group had the lowest Ra values and the AP group the highest roughness values, with mean and standard deviation respectively 0.17 (±0.11) and 0.52 (±0.10). After aging, the AA group had the lowest averages and the PQ group the highest Ra values, being 0.38 (±0.20) and 1.33 (±0.32), respectively. The results showed a statistically significant difference when the samples were finished with drills. Conclusion: RAQA requires polishing after finishing with drills, as the lack of polishing will compromise the surface smoothness of the material.(AU)

Estabilidad de Color de Tres Resinas Nanohíbridas en Relación al Tipo Pulido Realizado

El color de las restauraciones se considera una de las características más exigidas por los pacientes, cuyo éxito final dependerá de mantenerse en el tiempo, sin sufrir alteraciones. El objetivo de este estudio fue determinar la estabilidad de color que experimentan las resinas al ser sumergidas en una sustancia pigmentante en función al factor tiempo y al tipo de pulido final realizado. Estudio experimental in vitro de tres resinas de nanopartículas: Filtek Z-350 XT® (3M), Brillant NG® (Coltene), Tetric N-Ceram® (Vivadent) donde se comparó la estabilidad de color al ser sumergidas en café. Se confeccionaron 120 discos de resinas (color esmalte A3) divididos posteriormente en dos grupos: Grupo 1 protocolo habitual de pulido Grupo 2: protocolo habitual más sellador fotocurable Biscover® (Bisco). Las muestras fueron almacenadas en agua destilada en estufa a 37° durante 24 hs para su hidratación. Se registró el color utilizando el colorímetro Kónica Minolta®. Posteriormente se sumergieron las muestras en café, y se tomó nuevamente el color a las 24 hs y a los 7 días. Los datos fueron analizados estadísticamente mediante análisis de varianza y test de compación de Tukey. Se observó que la resina que más se pigmentó en el grupo 1 correspondió a la resina Filteck Z-350 con DE: 4,68 a las 24 hs y DE: 5,53 a los 7 días. Al analizar el grupo 2 las tres resinas se mantuvieron en valores bajos de DE: 0,96 a 1,42 en ambos períodos. Al sumergir las resinas en una sustancia pigmentante, la alteración del color se va produciendo en función del tiempo. Sin embargo, el uso complementario de un sellador fotocurable como pulido mejora significativamente la estabilidad de color en estos materiales, factores que el clínico debe tener en cuenta para lograr el éxito de sus restauraciones.

The color of the restorations is considered one of the characteristics most demanded by patients, whose final success will depend on being maintained over time, without undergoing alterations. The objective of this study was to determine the color variations experienced by reinforced resins when immersed in a pigmenting substance as a function of the time factor and the type of final polishing performed. In vitro experimental study of three nanoparticle resins: Filtek Z-350 XT® (3M), Brillant NG® (Coltene), Tetric N-Ceram® (Vivadent) where color stability was compared when immersed in coffee. 120 Discs of resins (enamel color A3) were made and subsequently divided into two groups: Group 1 usual polishing protocol Group 2: usual protocol plus Biscover® (Bisco) light-curing sealer. The samples were stored in distilled water in an oven at 37 ° for 24 hours for hydration. Color was recorded using the Konica Minolta® colorimeter. Subsequently, the samples were immersed in coffee, and the color was taken again at 24 hours and 7 days. Data were statistically analyzed using analysis of variance and Tukey's comparison test. It was observed that the most pigmented resin in group 1 corresponded to the Filteck Z-350 resin with DE: 4.68 at 24 hours and DE: 5.53 at 7 days. When analyzing group 2, the three resins maintained low DE values: 0.96 to 1.42 in both periods. By immersing the resins in a pigmenting substance, the change in color occurs over time. However, the complementary use of a light-curing sealer such as polishing significantly improves color stability in these materials, factors that the clinician must take into account to achieve the success of their restorations.

Sistemas de pulido para restauraciones cerámicas. Revisión de la literatura / Polishing systems for ceramic restorations. Literature review

El pulido es un paso de suma importancia en el flujo de trabajo de las restauraciones cerámicas, después de realizado un ajuste con puntas o piedras diamantadas, ya que disminuye la rugosidad de las superficies tratadas. Esto repercute positivamente en las propiedades mecánicas y ópticas del material. Sin embargo, la poca literatura disponible acerca de este procedimiento hace que sea pasado por alto. Debido a esto, el presente articulo tuvo como objetivo realizar una revisión bibliográfica sobre los diferentes protocolos de pulido para las diversas restauraciones cerámicas de mayor uso: Feldespática, disilicato de litio y zirconia en sus diferentes presentaciones. Se describen aspectos relevantes sobre el pulido mecánico, la rugosidad superficial y los sistemas de pulido actuales para cerámicas.

Polishing is an extremely important step in the workflow of ceramic restorations, after adjustment with diamond burs or stones, as it reduces the roughness of the treated surfaces. This has a positive impact on the mechanical and optical properties of the material; however, the limited literature available about this procedure makes it to be overlooked. Therefore, the aim of this article was to review the literature on the different polishing protocols for the most used ceramic restorations: Feldspathic, lithium disilicate and zirconia ceramics. Relevant aspects on mechanical polishing, surface roughness and current polishing systems for ceramics are described.

Comparison of the polishing effects of polyetheretherketone materials under different chairside polishing systems / 口腔疾病防治

Objective @# The polishing effects of different compositions of chairside polishing systems on polyetheretherketone (PEEK) were compared to provide a reference for the rational selection of polishing systems for this material in clinical settings. @*Methods @#A total of 108 specimens were made from ShushijieTMPEEK crown and bridge materials, Bio-PAEK® dental PEEK, and BioHPP® PEEK. Thirty-six specimens of each material were randomly divided into 6 groups on average based on their polishing technique: OptiDisc®, Super-Snap® Rainbow Technique Kit, VITA ENAMIC®Clinical Polishing Set, Sof-LexTM Diamond Polishing System, Visio.lign Finishing Kit for Composite Veneers, and CERAMAGE Polishing Kit, LavaTM Ultimate ceramic and VITA ENAMIC ceramics were set as the control groups, and 6 specimens were made in each material, polished by Sof-LexTM Diamond Polishing System and VITA ENAMIC® Polishing Set clinical, respectively, according to the manufacturers’ suggestions. The surface roughness (Ra value and Sa value) and gloss of each set were measured. The surface morphologies of the polished specimens were observed by scanning electron microscopy.@*Results @#Surface roughness (Ra value and Sa value) and gloss were mainly influenced by the type of polishing system, and they varied between PEEK material types. The Sof-LexTM Diamond Polishing System produced the highest surface roughness and the lowest gloss values for PEEK materials, while the Super-Snap® Rainbow Technique Kit, Visio.lign Finishing Kit for Composite Veneers and CERAMAGE Polishing Kit resulted in low surface roughness values. The Visio.lign Finishing Kit for Composite Veneers and CERAMAGE Polishing Kit exhibited high gloss values. Polishing paste particles were observed embedded on the surfaces of the PEEK materials polished by the Visio.lign Finishing Kit for Composite Veneers; the surfaces of specimens polished by the CERAMAGE Polishing Kit were smooth, without polishing paste particle residue. Using the same polishing system, the best polishing results were obtained with BioHPP® among the PEEK materials tested. The surface roughness values of the three tested PEEK materials polished by the CERAMAGE Polishing Kit were similar to those of the LavaTM Ultimate ceramic and VITA ENAMIC ceramic, but the gloss was higher than that of both. @*Conclusion @# CERAMAGE Polishing Kit was recommended for polishing all three tested PEEK materials, achieving a good polishing effect, with similar surface roughness and higher gloss characteristics comparable to those of polished computer-aided design and manufacturing (CAD/CAM) resin-matrix ceramics.

Three-dimensional printed 316L stainless steel cardiovascular stent's electrolytic polishing and its mechanical properties / 生物医学工程学杂志

The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0-10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.

Effect of anterior capsule polishing on the visual quality after cataract surgery / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the effect of anterior capsule polishing on visual quality after phacoemulsification.METHODS: Prospective randomized control study. A total of 65 patients(73 eyes)with age-related cataract who underwent phacoemulsification combined with intraocular lens(IOL)implantation in the Emergency General Hospital between November 2021 and June 2022 were included. These patients were randomly assigned to two groups, with one group(anterior polishing group)underwent anterior and posterior capsule polishing(30 cases, 35 eyes), while the other(control group)receive routine posterior capsule polishing(35 cases, 38 eyes). Best corrected visual acuity was observed at 1wk, 1, 3 and 6mo after operation. Area of anterior capsule orifice was measured at 3 and 6mo after operation. Meanwhile, posterior capsular opacification(P score), IOL tilt and decentration were recorded by Pentacam Scheimpflug system. In addition, wavefront aberration, Strehl ratio(SR)of point spread function(PSF)and modulation transfer function(MTF)were evaluated by OPD-Scan Ⅲ.RESULTS: At 1wk, 1, 3 and 6mo after operation, best corrected visual acuity in anterior polishing group is significantly better than that of control group(P<0.05). There were no significant differences in area of anterior capsule opening, P score, IOL decentration, SR of PSF and MTF between two groups at 3 and 6mo after operation(P>0.05). At 3mo follow-up, no significant differences in IOL tilt and wavefront aberration were measured between two groups either(P>0.05). However, IOL tilt [(1.65±0.60)° vs.(2.34±0.43)°, P<0.001] and wavefront aberration(0.03±0.01μm vs. 0.06±0.03μm, P<0.001)in anterior polishing group were significant lower compared to control group at 6mo after operation.CONCLUSION: 360° polishing of anterior and posterior capsule during phacoemulsification can improve best corrected visual quality, with reduced IOL tilt, lower wavefront aberration and better visual quality.

Evaluation of different composite resin finishing and polishing protocols by confocal laser scan microscopy

Aim This study aimed to analyze the influence of finishing and polishing (F/P) protocols on resin surface through roughness (Ra) values and laser scan microscopy observations. Methods Forty-eight (n=48) resin specimens were sorted into four groups (n=12), according to the type of resin used: Filtek Z250 (Z250), Filtek Z350 (Z350), Filtek One Bulk Fill (BF), Filtek P60 (P60). The specimens were sorted into six groups according to the type of F/P system used (n=2/group): Control group, Diamond bur (KG Sorensen), Soflex Pop-On Discs (3M ESPE), Soflex Spiral (3M ESPE), Dura Gloss (American Burs), and Praxis (TDV). Results The highest roughness values (Ra) were attributed to BF group for all F/P systems, except for the Soft-Lex PopOn discs. The Soft-Lex PopOn, Spiral, and Praxis discs presented a better performance for the surface treatment of the tested composite resins. Regardless of the restorative material, the use of diamond bur or single-step abrasive rubber (Dura Gloss) were associated with the highest Ra values. Conclusion The effect of F/P systems on Ra is material-dependent and instrument or system-dependent.

Effects of the Finishing Protocols and Oral Hygiene Procedures in the Microhardness and Surface Roughness of CAD/CAM Ceramics

ABSTRACT: The objective of this in vitro study was to evaluate the effects of finishing protocols and oral hygiene procedures on the surface and mechanical properties of CAD/CAM ceramics. Specimens (n = 96, (15x10x2mm) of the leucite glass-ceramic (LGC) and feldspathic ceramic (FP) received mechanical polishing or glazing. Surface roughness (Ra) and microhardness (VHN) were obtained with a profilometer and a hardness tester, respectively, before and after each oral hygiene procedure (TB: toothbrushing; PB: prophylaxis with paste and rubber cup; and BJ: prophylaxis with bicarbonate jet). ANOVA, paired t and Tukey's tests were applied (a=0.05). For both materials, only BJ affected Ra's values when mechanical polishing was performed. Moreover, no significant variations in VHN were observed only for LGC glazed with TB. Significant Ra and VHN changes in both materials were observed with BJ. Besides, BJ exhibited similar effects to TB on VHN, regardless of the material and finishing protocol used. Changes in mechanical and surface properties varied with the finishing protocol and the oral hygiene method. In general, prophylaxis with bicarbonate jet was the most harmful method for both materials and the type of finishing protocol did not have a protective effect against changes produced by oral hygiene methods.

RESUMEN: El objetivo de este estudio in vitro fue evaluar los efectos de los protocolos de acabado y los procedimientos de higiene oral sobre la superficie y las propiedades mecánicas de las cerámicas CAD/CAM. Los especímenes (n = 96, (15x10x2mm) de vitrocerámica de leucita (LGC) y cerámica feldespática (FP) recibieron pulido mecánico o glaseado. La rugosidad de la superficie (Ra) y la microdureza (VHN) se obtuvieron con un perfilómetro y un probador de dureza, respectivamente, antes y después de cada procedimiento de higiene oral (TB: cepillado dental; PB: profilaxis con pasta y vaso de hule; y BJ: profilaxis con chorro de bicarbonato). Se aplicaron ANOVA, t pareada y prueba de Tukey (a=0.05). Para ambos materiales, solo BJ afectó los valores de Ra cuando se realizó el pulido mecánico. Además, no se observaron variaciones significativas en VHN solo para LGC vidriado con TB. Se observaron cambios significativos de Ra y VHN en ambos materiales con BJ. Además, BJ exhibió efectos similares a TB en VHN, independientemente del material y protocolo de acabado utilizado Los cambios en las propiedades mecánicas y superficiales variaron con el protocolo de acabado y el método de higiene oral. En general, la profilaxis con chorro de bicarbonato fue el método más perjudicial, tanto los materiales como el tipo de protocolo de acabado no tuvieron un efecto protector frente a los cambios producidos por los métodos de higiene oral.

Effects of can walking anterior and posterior capsule polishing combined with tension ring implantation on lens capsular stability after phacoemulsification for ultra-high myopia cataract / 中华显微外科杂志

Objective:To observe the effects of polishing the anterior and posterior capsule with irrigation/aspiration (I/A) injection needle and capsular tension ring (CTR) implantation on intraocular lens (IOL) capsular stability after phacoemulsification for ultra-high myopia with 2.0 mm coaxial micro incision.Methods:This is a prospective randomized controlled study. There were 40 patients(80 eyes) aged 46-72 years old with ultra-high myopia cataract. The grade of lens opacity was grade II-IV, and the diopter was -10 D - -24 D. During 2.0 mm coaxial micro incision phacoemulsification, adopt coin tossing method randomly, 1 eye was operated using the anterior and posterior capsule polishing 360° with I/A injection needle combined with CTR implantation as the experimental group(40 eyes), the other eye was neither polished nor CTR implantated as the control group(40 eyes). The operation interval of both eyes was less than 1 week. The size of anterior capsular orifice, effective intraocular lens position(ELP), IOL eccentricity and posterior capsular opacification(PCO) were recorded at 1 week, 1, 3 and 6 months after operation in outpatient clinic. Two independent sample t-test and Fisher exact probability test were used to compare the differences between the 2 groups. P<0.05 was defined significant difference. Results:During the follow-up period, there were no significant change in the anterior capsule area, IOL eccentricity and ELP in the experimental group. However in the control group, the anterior capsular area decreased gradually with time, and gradually IOL eccentricity increased and ELP decreased. There was no significant difference between the 2 groups in each observation index at 1 week after operation, but it was ELP that first showed the difference tendency( P<0.01). The ELP of the control group was significantly lower than that of the experimental group at 1, 3 and 6 months after operation( P<0.05). There was no significant difference in anterior capsule area and IOL eccentricity between the 2 groups at 1 and 3 months after operation( P>0.05), but there was a significant difference at 6 months( P<0.05). In terms of PCO, the incidence of PCO was 0%, 2.5% and 7.5% in the experimental group and 5.0%, 17.5% and 32.5% in the control group respectively at 1, 3 and 6 months after operation. The incidence of PCO in the experimental group was significantly lower than that in the control group( P<0.05). Conclusion:Ultra-high myopia with cataract are prone to have capsular contraction after operation, which is characterized by IOL instability and anterior capsular orifice narrowing gradually. Combined 360° anterior and posterior capsular polishing with tension ring implantation in operation can effectively maintain the stability of ELP, reduce the degree of contraction of anterior capsular orifice, reduce the eccentricity of IOL and the incidence of PCO. Polishing the anterior and posterior capsule with I/A injection needle combined with CTR implantation, is safe and effective for patients with ultra-high myopia cataract.

Efficacy of combined application of glycine powder air-polishing in non-surgical treatment of peri-implant diseases / 北京大学学报(医学版)

OBJECTIVE@#To compare the clinical efficacy of combined application of glycine powder air-polishing and mechanical submucosal debridement in non-surgical treatment of peri-implant diseases.@*METHODS@#A randomized controlled clinical study was carried out on patients diagnosed with peri-implant diseases in the Department of Periodontology, Peking University School and Hospital of Stomatology, between May of 2020 and June of 2021.Twenty-eight patients with totally sixty-two implants were enrolled.The patients were randomly divided into the test group and control group. The patients in the test group (13 subjects/32 implants) received mechanical submucosal debridement using titanium curettes combined with application of glycine powder air-polishing, while the control group (15 subjects/30 implants) received mechanical submucosal debridement using titanium only. Clinical parameters, such as plaque index (PLI), pocket probing depth (PPD), bleeding index (BI) and the percentage of suppuration on probing on implants' level (SoP%) were measured at baseline and 8 weeks after non-surgical intervention. Changes and group differences of clinical parameters of the implants before and 8 weeks after non-surgical intervention were compared.@*RESULTS@#Mean PLI, PPD, BI of both the test group and control group significantly reduced 8 weeks after non-surgical intervention (P < 0.05). Compared with the control group, the test group achieved lower BI (2.7±0.8 vs. 2.2±0.7, P < 0.05), more reduction of BI (0.6±0.7 vs. 1.1±0.6, P < 0.01) and more reduction of SoP% (21.9% vs. 10%, P < 0.05) after non-surgical intervention. Both the control and test groups exhibited comparable PLI and PPD reductions (P>0.05). For the implants diagnosed with peri-implant mucositis, the test group revealed more signi-ficant reduction in BI and SoP% than the control group (1.0±0.7 vs. 0.4±0.7, P=0.02; 6.3% vs. 0, P=0.012). There was no significant difference existing in PLI and PD improvement between the control group and test group (P>0.05). For the implants diagnosed with peri-implantitis, there was no significant difference existing in PLI, PPD, BI and SoP% improvement values between the test and control groups (P>0.05). No complications or discomforts were reported during the study.@*CONCLUSION@#Both treatment procedures could relieve the inflammation of peri-implant soft tissue. Non-surgical mechanical submucosal debridement combined application of glycine powder air-polishing is associated with significant reduction of soft tissue bleeding and suppuration on probing especially in the implants diagnosed with peri-implant mucositis.

Effects of different polishing procedures on the surface roughness and hardness of polyether ether ketone (PEEK) / Efecto de diferentes procedimientos de pulido en la rugosidad y dureza de superficie de un material a base de poliéter éter acetona (PEEK)

ABSTRACT: There is insufficient information about the chairside polishing methods of polyether ether ketone material. Therefore, it is aimed in this study to investigate the effects of different polishing processes on polyether ether ketone surface roughness and hardness. A total of 66 disc-shaped specimens made of polyether ether ketone were used in this study. The specimens were polished conventionally and randomly divided into three groups (n=22). One group was designated as the control group, and no further treatment was applied. In the other two groups, the specimens' surfaces were abraded with diamond burs and polished using two different polishing kits. Their surface roughness and Vickers hardness were measured, and environmental scanning electron microscopy and atomic force microscopy examinations were performed. The data were statistically analysed using analysis of variance and Tukey's honest significant difference test (α=0.05). There were no statistically significant differences between the control and polishing kit groups in terms of either surface roughness or Vickers hardness (p>0.05). The polishing kits can be used reliably and effectively for polishing polyether ether ketone materials.

RESUMEN: No existe información suficiente sobre los métodos de pulido del material poliéter éter cetona. Por tanto, este estudio tiene como objetivo evaluar el efecto de diferentes procedimientos de pulido sobre la rugosidad y dureza de superficie de un material a base de poliéter éter acetona. Un total de 66 muestras en forma de disco fueron realizadas. Los especímenes fueron divididos en tres grupos (n=22). Un grupo fue designado como grupo de control, siendo que no se aplicó ningún tratamiento. En los otros dos grupos, las superficies de las muestras se lijaron con fresas de diamante y se pulieron con dos kits de pulido diferentes. Se investigó la rugosidad de superficie y la dureza Vickers en los diferentes grupos. También fueron evaluadas muestras representativas en microscopía electrónica de barrido y microscopía de fuerza atómica. Los datos se analizaron estadísticamente mediante el análisis de varianza (ANOVA) y el método de Tukey (α=0.05). No hubo diferencias estadísticamente significativas entre los grupos en términos de rugosidad de superficie o Dureza Vickers (p>0,05). Los kits de pulido se pueden utilizar de forma eficaz para el pulido de materiales a base de poliéter éter acetona.

Influence of Finishing/Polishing in Surface Roughness of Conventional Nanocomposites and Bulk-Fill / Influência do Acabamento/Polimento na Rugosidade de Superfície das Resinas Compostas Nanoparticuladas Convencional e Bulk-Fill

The choice of the best finishing/polishing methods for composite resin restorations is critical to the choice of excellence results related to longer clinical longevity. The objective of the study was to evaluate the influence of finishing and polishing systems on the surface roughness of a Nanoparticulate and Bulk-fill resin. For the research, 40 sample disks were prepared for each composite: single-increment (BF) (Bulk Fill 3M), both 2 mm thick and 10 mm in diameter (FZ) (Filtek Z350, 3M). The specimens were randomly divided into 4 groups with 10 samples each, according to the different materials to which they were subjected to the finishing and polishing protocols: control [C]- diamond tip (FG 4137F FAVA); [EN] polishing discs (Enhance, Dentsply); [SL] Abrasive discs (Sof-Lex Pop-on, 3M) and [PD] felt disc + Polishing paste (Diamond Excel, FGM). A surface roughness (Ra) was verified with a roughness meter in three different data volumes and calculated as arithmetic means. Data were statistically treated by one way ANOVA followed by test t and student t test. Regardless of the data tested, evidence of the systemic controlling against different systems for polishing control with control (p <0.05). PD presented statistically greater roughness to the EN and SL (p <0.001), these in turn obtained similar performance and presented the lowest values of roughness for both composites (p> 0.05). The different finishing / polishing methods influenced the surface roughness of both composites, observing for Sof-lex and Enhance lower Ra values. (AU)

A escolha dos adequados métodos de acabamento/polimento para restaurações de resina composta é fundamental para obtenção de resultados de excelência, relacionados a maior longevidade clínica. O objetivo desse estudo foi avaliar a influência dos sistemas de acabamento e polimento na rugosidade de superfície das resinas nanoparticuladas convencional e bulk-fill. Para a pesquisa foram confeccionados 40 discos de amostra para cada compósito: Convencional [FZ] (Filtek Z350, 3M) e de incremento único [BF] (Filtek Bulk Fill, 3M), ambas com 2 mm de espessura e 10 mm de diâmetro. Foram divididos aleatoriamente em 4 grupos com 10 amostras cada, de acordo com os diferentes protocolos que receberam, sendo: controle (C) ponta diamantada (FG 4137F, FAVA); (EN) discos de silicone (Enhance, Dentsply); (SL) discos abrasivos (Sof-Lex Pop-on, 3M); (PD) Feltro + Pasta diamantada (Diamond Excel, FGM). A rugosidade de superfície (Ra) foi verificada com um rugosímetro em três leituras de diferentes direções e calculadas as médias aritméticas. Os dados foram tratados estatisticamente pelos testes ANOVA 1 fator seguido pelo teste t e t de student (p<0,05). Independente da resina testada, evidenciou-se diminuição da rugosidade pelos diferentes sistemas de polimento frente ao grupo controle (p<0,05). PD apresentou rugosidade estatisticamente maior à EN e SL (p<0,001), estes últimos que por sua vez obtiveram desempenho semelhante e apresentaram os menores valores de rugosidade para ambos os compósitos (p>0,05). Os diferentes métodos de acabamento/polimento influenciaram na rugosidade de superfície dos dois compósitos testados, observando para Sof-lex e Enhance menores valores de Ra. (AU)

Efeito do acabamento e polimento sobre a topografia superficial de uma resina composta convencional e uma bulk fill / Effect of finishing and polishing on the surface topography of a conventional compound resin and a bulk fill / Efecto de acabado y pulido en la topografía superficial de una resina compuesta convencional y un llenado a granel

Introdução:As atuaisresinas Bulk-Fill apresentamcomovantagens e propriedades: menor tempo clínico, baixa contração de polimerização, maior translucidez, entre outros. Objetivo:Avaliar a topografia superficial de restaurações com diferentes tipos de resina composta antes e após submetê-las a diferentes sistemas de acabamento e polimento. Metodologia:Confecção de100 corpos de prova, sendo 50 de cada composto resinoso, apresentando cinco grupos (n=10) sorteados de forma aleatória, de acordo com o sistema de acabamento e polimento empregado. Foram utilizadas as resinas Filtek Z350 XT e a Bulk Fill Filtek One Bulk Fill e os sistemas de acabamento e polimento: Discos de Lixa Sof-Lex Pop On Kit;Discos Diamantado Espiral Sof-Lex; Ponta Enhance e Broca Carbide Multilaminada nº 0283F, que foram comparados com superfície deixada pela Tira de Poliester (Controle Negativo). Após 7 dias de armazenamento em água destilada, os corpos de provaforam submetidos aoMicroscópio Eletrônico de Varredura.Resultados:Os corpos de provada resina Bulk Fill tiveram como melhor resultado o sistema de acabamento e polimentocom broca carbidee resultado não satisfatório com discodiamantado espiral Sof-lex, enquanto a ponta Enhance e lixa Sof-lex Pop Ontiveram resultados semelhantes. Os corpos de prova da resina Filtek Z350 XT tiveram melhor aspecto visual de lisura no grupo controle negativoe pior resultado no grupo com disco diamantado espiral Sof-lex. Conclusões:Dessa forma, o sistema que apresentou melhor resultado foi a broca Carbidena resina Bulk Fill, enquanto a Filtek Z350 XT apresentou-se melhor no grupo controle. Porém, ainda são necessáriosestudos para se chegar em um protocolo de acabamento e polimento mais eficiente (AU).

Introduction:The current Bulk-Fill resins have the following advantages and properties: less clinical time, low polymerization shrinkage, greater translucency, among others.Objective:Toevaluate the topography of restorations with different types of composite resin before and after submitting them to different finishing and polishing systems.Methodology:Manufacture of 100 specimens, 50 of each resin compound, presenting five groups (n = 10) drawn at random, according to the finishing and polishing system employed. Filtek Z350 XT resins and Bulk Fill Filtek One Bulk Fill andfinishing and polishing systems were used: Sof-Lex Pop On Kit Sanding Discs; Diamond Spiral Sof-Lex Discs; Tip Enhance and Multilaminated Carbide Drill nº 0283F, which were compared with the surface left by the Polyester Strip (Negative Control). After 7 days of storage in distilled water, the specimens were submitted to a Scanning Electron Microscope.Results:The Bulk Fill resin specimens had the best result of the finishing and polishing system with carbide drill and unsatisfactory result with Sof-lex spiral diamond disc, while the Enhance tip and Sof-lex Pop On sandpaper had similar results. The Filtek Z350 XT resin specimens had a better visual aspect of smoothness in the negative control group and a worse result in the group with Sof-lex spiral diamond wheel.Conclusions:Thus, the system that showed the best result was the Carbide drill in Bulk Fill resin, while Filtek Z350 XT was better in the control group. However, studies are still needed to arrive at a more efficient finishing and polishing protocol (AU).

Introducción:Las actuales resinas Bulk-Fill tienen las siguientes ventajas y propiedades: menor tiempo clínico, baja contracción de polimerización, mayor translucidez, entre otras.Objetivo: Evaluar la topografía de restauraciones con diferentes tipos de resina compuesta antes y después de someterlas a diferentes sistemas de acabado y pulido.Metodología: Fabricación de 100 probetas, 50 de cada resina compuesta, presentando cinco grupos (n = 10) extraídos al azar, según el sistema de acabado y pulido empleado. Se utilizaron resinas Filtek Z350 XT y Bulk Fill Filtek One Bulk Fill y sistemas de acabado y pulido: Discos de lijado Sof-Lex Pop On Kit; Discos Sof-Lex en espiral de diamante; Broca Realce de Punta y Carburo Multilaminado nº 0283F, que fueron comparadas con la superficie dejada por la Tira de Poliéster (Control Negativo). Después de 7 días de almacenamiento en agua destilada, lasmuestras se sometieron a un Las muestras de resina Bulk Fill tuvieron el mejor resultado del sistema de acabado y pulido con broca de carburo y un resultado insatisfactorio con el disco de diamante en espiral Sof-lex, mientras que la punta Enhance y el papel de lija Sof-lex Pop On tuvieron resultados similares. Las muestras de resina Filtek Z350 XT tuvieron un mejor aspecto visual de suavidad en el grupo de control negativo y un peor resultado en el grupo con disco de diamante en espiral Sof-lex.Conclusiones: Así, el sistema que mejor resultado mostró fue la broca Carbide en resina Bulk Fill, mientras que Filtek Z350 XT fue mejor en el grupo control. Sin embargo, aún se necesitan estudios para llegar a un protocolo de acabado y pulido más eficiente (AU).

Oxygen inhibition of surface composites and its correlation with degree of conversion and color stability

Abstract This study investigated the effects of oxygen inhibition and finishing/polishing procedures on the composite resin properties. One bulk-fill and two conventional composite resins (nanoparticle and microhybrid) were evaluated. Specimens were prepared using 4 surface treatments: control, no treatment; Gly, oxygen inhibition with glycerin; FP, finishing and polishing; Gly + FP, glycerin followed by finishing and polishing. The degree of conversion (DC) was measured using Fourier Transformed Infrared Spectroscopy (FTIR) immediately and after 15 days (n=5). Color stability (ΔEab, and ΔE00) and opacity were evaluated using a spectrophotometer after 15 days of immersion in coffee, using the CIELAB system (n=5). Data were analyzed by two-way ANOVA and Tukey tests (α=0.05) and opacity by two-way repeated-measures ANOVA. Glycerin usage increased significantly the DC however had no influence on the ΔEab, ΔE00 and, opacity values. Finishing and polishing reduced ΔEab and ΔE00 values, regardless of composite resins. Microhybrid showed higher opacity, followed by the nanoparticle and bulk fill, regardless of surface treatment. Post-polymerization polishing procedures resulted in lower conversion than using an oxygen inhibitor agent (Gly condition), but similar staining caused by coffee.

Resumo Este estudo investigou os efeitos da inibição de oxigênio e dos procedimentos de acabamento/polimento nas propriedades das resinas compostas. Foram avaliadas uma resina composta bulk fill e duas resinas convencionais (nanoparticulada e microhíbrida). Os espécimes foram confeccionados, variando o tratamento de superfície: controle, sem tratamento; glicerina (inibidor de oxigênio); acabamento e polimento; glicerina + acabamento e polimento. O grau de conversão (GC) foi medido pela Espectroscopia de Infravermelho Transformada de Fourier (FTIR) imediatamente e após 15 dias da confecção dos espécimes (n=5). Os índices de alteração de cor ΔEab, ΔE00 e opacidade foram avaliados por meio de espectrofotômetro, após 15 dias de imersão no café, utilizando o sistema CIELAB (n=5). Os dados da alteração da cor foram analisados pelos testes ANOVA de dois fatores e Tukey (α=0,05) e a opacidade por ANOVA de medidas repetidas. O uso de glicerina aumentou significativamente o GC, no entanto, não teve influência sobre os valores ΔEab e ΔE00. O acabamento e o polimento reduziram os valores de ΔEab e ΔE00, independentemente da resina composta. A resina microhíbrida apresentou maior opacidade, seguida pela nanoparticula e bulk-fill, independentemente do tratamento de superfície. O acabamento e polimento resultou em menor grau de conversão das resinas compostas se comparado ao uso de um agente inibidor de oxigênio (glicerina), porém apresenta resultados similares para a pigmentação pelo café.

The effect of different finishing and polishing procedures on the surface gloss of Bulk-Fill resin composites

STATEMENT OF THE PROBLEM: The literature still lacks evidence regarding which polishing techniques have the ideal clinical outcomes for bulk-fill resin composites. PURPOSE: This study evaluated the surface gloss of two commercially available bulk-fill resin composites after different polishing procedures and characterized their micromorphology via scanning electron microscopy. MATERIAL AND METHODS: 80 bulk-fill compactable composite resin discs were created. The control group was left untreated, and remaining samples were subjected to different polishing techniques. Gloss units were measured and surface morphology of disc samples was assessed. The Tukey post-hoc test was used to identify any differences. RESULTS: Statistically significant differences were found between the different polishing systems applied to Filtek BulkFill Posterior and Tetric N Bulk-Fill. No differences were found when the same polishing system was applied for both resins. The highest gloss values were obtained in the control group and the ENA Shiny system; the lowest were obtained with SofLex XT and Soflex Spiral Wheels for the bulk-fill composite resins studied. CONCLUSIONS. Diamond pastes have the highest gloss behavior, followed by diamond rubber points. The systems with aluminum oxide discs present the lower gloss behavior. SEM images provided useful evidence, and future studies should include an evaluation over time.

Effect of capsular LECs removal on capsular stability in patients with high myopia and cataract / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the effect of LECs removal on the stability of lens capsule bag in patients with high myopia.<p>METHODS: From March 2018 to April 2019, 98 cases(120 eyes)of cataract patients with high myopia were treated in Cataract Department of Hebei Province Eye Hospital. They were divided into two groups according to whether the LECs were removed during the operation. In group A, the anterior and posterior capsule were polished in 50 cases(60 eyes), while in group B, 48 cases(60 eyes)were not polished. During the follow-up period we used anterior segment OCT to detect the change of effective intraocular lens position(ELP), the eccentricity of intraocular lens(IOL)and the reduction of anterior capsule opening in the two groups, and used slit lamp to observe the occurrence and degree of PCO.<p>RESULTS: We compared the changes of ELP(0.16±0.06mm <i>vs</i> 0.55±0.07mm)and the changes of contraction of anterior capsule(0.18 ± 0.16mm <i>vs</i> 0.92 ± 0.13mm)on the first day and three months after operation. Three months after operation, we compared the IOL eccentricity of the two groups(0.02±0.005mm <i>vs</i> 0.69±0.23mm). There were differences between the two groups(<i>P</i><0.05). At 3mo after operation, the PCO of group A was observed by slit lamp: grade I 4 eyes, grade II 2 eyes, grade III 1 eye. The PCO of group B: grade I 16 eyes, grade II 8 eyes, grade III 4 eyes and grade IV 3 eyes. There was significant difference between the two groups(<i>Z</i>=-4.765, <i>P</i><0.01).<p>CONCLUSION: The removal of LECs could reduce the contraction of anterior capsule, decrease the change of ELP and enhance the stability of bag IOL complex, which played a good role in reducing PCO.

Surface Roughness of Tooth Coloured Restorative Materials

@#This study compared the surface roughness of selected tooth coloured restorative materials that were polished according to manufacturers’ instructions and Sof-Lex. It also assessed the surface roughness of polished materials after thermocycling. Filtek Z350XT, Beautifil-Bulk Restorative and Cention N, were used in this study. A stainless steel mould (10mm diameter x 2mm height) was used to fabricate 75 cylindrical specimens: 15 Filtek Z350XT (FZ), 30 Beautifil-Bulk Restorative (BB) and 30 Cention N (CN). All 15 FZ specimens were polished with Sof-Lex. Fifteen BB and CN specimens were polished according to manufacturers’ instructions. The remaining fifteen BB and CN specimens were polished using Sof-Lex. All the specimens were subjected to thermocycling (1000 cycles). Surface roughness was assessed quantitatively with profilometry after specimen preparation (Mylar stage), polishing and thermocycling. Data were analysed using SPSS version 25.0 at α=0.05. When polished according to manufacturers’ instructions, BB had the lowest mean surface roughness (Ra) values (0.13±0.01μm) followed sequentially by CN (0.14±0.03μm) and FZ (0.15±0.02μm). The differences were not statistically significant. When polished with Sof-Lex, BB exhibited the smoothest surface (0.116±0.03μm) followed sequentially by and FZ (0.150±0.02μm) and CN (0.157±0.02μm). Thermocycling caused an increase in the Ra. The differences were statistically significant. All materials tested had Ra values below the threshold value of 0.2 µm at Mylar stage and after polishing with their recommended polishing system and Sof-Lex. Thermocycling produced rougher surfaces that did not exceed the threshold Ra value. Polishability was material dependent.

Effect of fine capsule treatment on the visual quality of diffractive multifocal intraocular lens / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the effect of fine capsule treatment on the visual quality of diffractive multifocal intraocular lens.<p>METHODS: Ninety-eight patients(120 eyes)with DMIOL implanted in cataract Department of Hebei Eye Hospital from March 2017 to April 2018. They were randomly divided into A group and B group. 60 eyes in each group. Group A patients were treated with anterior and posterior capsular polishing and posterior continuous circular capsulorhexis, while in B group the fine capsule treatment was not performed. The UCDVA, UCIVA, UCNVA, visual quality, intraocular lens neutrality and PCO incidence were compared 6mo after operation.<p>RESULTS: At 6mo after operation, UCDVA, UCIVA and UCNVA in group A were superior to those in group B. The difference was statistically significant(<i>P</i><0.05). At 6mo after operation, the amount of eccentric intraocular lens in group A was less than that in group B. The difference was statistically significant(<i>P</i><0.05). PCO incidence: group A: 0 eyes; group B: 5 eyes(8.3%)in gradeⅠ, 3 eyes(5.0%)in grade Ⅱ, 2 eyes(3.3%)in grade Ⅲ.<p>CONCLUSION: In order to enhance the stability of IOL and maintain the long-term transparency of the optic axis, we performed fine polishing of the anterior and posterior capsule and continuous circular capsulorhexis of the posterior capsule. These could improve the visual quality and satisfaction of patients after surgery.