Clinical and patient reported outcomes of Vitamin E diffused highly cross-linked polyethylene liner versus moderately cross linked polyethylene liner in total hip arthroplasty: A meta-analysis

Introduction@#In the modern era of Medicine, total hip arthroplasty (THA) is found to last longer than ever before due to the fact that there has been improved bearing surfaces and materials available. Despite these modern approaches, failure caused by polyethylene wear, aseptic loosening, instability and mispositioning and even infection could affect THA survival. In the course of addressing anti-wear characteristics of the conventional polyethylene surface various approaches have been made. To date, there are very limited studies done in which polyethylene liner is better.@*General Objective@#To compare the effects of vitamin E diffused highly cross-linked polyethylene liner versus moderately cross-linked polyethylene liner in THA. @*Methodology@#Meta-analysis research design was used in this study. The primary investigators conducted a comprehensive literature search from Medline, Cochrane Library, PubMed, Elsevier, Google Scholar, Embase and ClinicalTrial.gov as electronic database. All randomized controlled trials comparing the effects of vitamin E diffused highly cross-linked polyethylene liner versus moderately cross-linked polyethylene liner in THA were included in the review. @*Conclusions@#The investigation disclosed no statistical significance between moderately cross-linked polyethylene liner and vitamin E diffused highly cross-linked polyethylene liner in terms of migration, head penetration and wear on mediolateral, longitudinal and anteroposterior axes after 2 and 5 years of undergoing THA. Moreover, the data pertaining to patient reported outcomes and clinical outcomes measure also indicated no statistical significance between moderately cross-linked polyethylene liner and vitamin E diffused highly cross-linked polyethylene liner. This indicates that vitamin E diffused highly cross-linked polyethylene liner is comparable with the conventional moderately cross-linked polyethylene liner. Vitamin E-infused highly cross-linked polyethylene ( VEPE) showed an almost similar stability with regard to the wear rates and the component showed similar stability with that of moderately cross-linked polyethylene liner.

Cytotoxicity and mechanical properties of the prosthetic liner / 中国康复理论与实践

@# Objective To investigate the current status of cytotoxicity and mechanical properties of the prosthetic liner on the market in China.Methods Six kinds of liner were collected, namely domestic 6 mm thick foam liner (A), domestic 5 mm thick EVA foam liner (B), German 5 mm thick EVA foam liner (C), Germany 12 mm thick PE foam liner (D), Iceland 3 mm thick silicone liner (E) and Germany 4 mm thick gel liner (F). Microscopic observation and thiazole blue colorimetry were used to detect the cytotoxicity. The content of small organic molecules was determined by the consumption of potassium permanganate. The tensile strength, elongation at break (%), and 100% tensile strength of the prosthetic liner were tested by material mechanics testing machine. The hardness was tested using the Shore hardness tester oo type.Results The cytotoxicity was grade 2 for prosthetic liners A, B, C and D, and was grade 0 for E and F. The redox substance content of prosthetic liners A、B、C exceeded 150 mg/kg. Except the prosthetic liner C, the hardness of the other products were all ≤ 70 HA. Except prosthetic liner D, the tensile strengths were > 1 MPa, breaking elongations were > 120.0%, 100% tensile strengths were > 0.9 MPa for other products.Conclusion Due to materials and production processes, the cytotoxicity and mechanical properties of the six samples are quite different.

Identification of Gastrodiae Rhizoma chromatographic peaks identification by liner calibration with two reference substances assisted / 药学学报

This study aimed to establish a method for positioning six chromatographic peaks occurred in HPLC profile of Gastrodiae Rhizoma. The "liner calibration with two reference substances" (LCTRS) method was used to calculate the retention time so as to assist in positioning of chromatographic peaks in terms of the prediction accuracy of retention time and the coincidence rate of chromatographic column. A total of 24 C18 chromatographic columns from different brands and types available were used to determine the retention times of six components in Gastrodiae Rhizoma, then the average retention time of each component was obtained as standard retention time (SRT). Parishin E (peak 3) and Parishin A (peak 6) were simultaneously taken as reference substance to forecast the retention time of the other four components by using the LCTRS method. Four different C18 columns were employed to verify the method. Meanwhile, for the purpose of comparison, the relative retention time (RRT) method was applied to forecast the retention time, by using Parishin E as the single reference substance. The comparison between LCTRS and RRT methods indicated that the former was more accurate in predicting the retention time and more applicable in utilization of chromatographic columns. This study demonstrated that the LCTRS method shows the superior performance in positioning of chromatographic peak, and therefore has a good prospect of application.

Role of Liners in Restorative Dentistry.

Tooth has two main organs- pulp and dentin which remain closely integrated. They depend on each other both functionally and anatomically, throughout the life of tooth. Protection of these tissues is important from trauma during cavity preparation or tooth preparation, from caries, from mechanical forces, from chemicals produced by bacteria and from galvanic shock and thermal injury. The main aim of the operative dentistry is to protect this tissue and preserve tooth vitality.(1) The purpose of a restoration is to replace missing tooth structure and provide the pulp adequate strength and protection from external insults. Sometimes, the restorations and \ or the restorative material is incapable of providing this property; hence, an auxiliary material such as liner and base or sub-base is required, which can fulfil this function. The material used to protect this tissue is called pulp protecting material or pulp capping material. For many decades clinicians have been using liners and bases under restorations. The type of auxiliary material to be used depends upon the minimum dentinal thickness which is left between the surface of the cavity and pulp. This is known as remaining dentin thickness (RDT). Dentin has excellent buffering capacity to neutralize the effects of cariogenic acids, and insulates the pulp from temperature increases during cavity percolation. The single most important criterion for protecting pulp is remaining dentinal thickness which is dependent upon the depth of cavity preparation.(2)

Design, Development And Delivery Of Rasagiline Mesylate From Monolithic Drug In Adhesive Matrix Patches

The purpose of this research was to prepare and evaluate monolithic drug-in-adhesive type patches of Rasagiline Mesylate (RM) containing penetration enhancer and having seven day wear property. Preformulation studies like solubility in permeation enhancers, compatibility study, transmission study, uptake study and crystallization study of Rasagiline Mesylate in various pressure sensitive adhesive polymers were performed. Transdermal system was prepared by solvent casting method. The effects of various permeation enhancers (Propylene Glycol, Oleic Acid, Isopropyl Palmitate, and lauryl lactate) on the ex-vivo transcutaneous absorption of Rasagiline Mesylate through human cadaver skin were evaluated by modified Franz diffusion cell system. Ex-vivo transcutaneous absorption of prepared transdermal patch was performed using different concentration of Lauryl lactate (3%, 5%, and 7%). In-vitro Adhesion testing (Peel, tack shear etc.) was performed on different dry GSM (Grams per Square Meter) of patch like 80GSM, 100 GSM and 150 GSM. The final transdermal patches were tested for appearance, weight of matrix, thickness, % assay of drug content, in-vitro adhesion testing, cold flow study and ex-vivo skin permeation studies. Based on crystallization study and adhesion testing, Durotak-4098 (14% drug concentration) was selected as pressure sensitive adhesive. Patch containing Lauryl lactate showed highest cumulative permeation compared to other permeation enhancers. The patch containing 5% laurel lactate showed greater transdermal flux (2.36 µg/cm2 /hr). Patch with 150 dry GSM showing promising adhesion properties. Backing film Scotchpak 9723 and release liner Saint Gobain 8310 was selected based on transmission and uptake study of Rasagiline Mesylate. Stability study indicates that developed formulation remains stable. In conclusion, the present research confirms the practicability of developing Rasagiline Mesylate transdermal system.

Effect of laryngeal mask and endotracheal tube ventilation on gastric insufflation during general anesthesia with ultrasound evaluation / 上海交通大学学报（医学版）

Objective • To observe the correlation between streamlined liner of pharynx airway (SLIPA) and gastric insufflation. Methods • Seventy patients who underwent elective general anesthesia in Jiading District Central Hospital Affiliated to Shanghai University of Medicine & Health Sciences from September 2017 to May 2018 were included. They were randomly divided into SLIPA group (S group, n=35) and endotracheal tube group (T group, n=35). The gastric antrum ultrasonography was performed at four time points before induction, immediately after intubation (insertion of laryngeal mask), before extubation (laryngeal mask), and immediately after extubation (laryngeal mask), to measure the cross sectional area (CSA) of gastric insufflation. Gastric intake was assessed by ultrasonic measurement of CSA and "comet tail sign" in ultrasound imaging. Pulse oxygen saturation (SpO2), end-tidal pressure of carbon dioxide (PETCO2), peak inspiratory pressure (PIP) and CSA were recorded and compared at the corresponding time points. Results • There was no significant difference in gastric insufflation rate between the two groups during anesthesia (P=0.894). There was no significant difference in SpO2 at each time point between the two groups (all P>0.05). At the end of surgery, PETCO2 in group S was significantly higher than that in group T (P=0.000). Conclusion • Compared with endotracheal tube, the SLIPA does not increase gastric insufflation during general anesthesia.

Evaluation of Interface Adhesion Between Silicone Soft Liners and Denture Base After Immersion With Denture Cleansers by Scanning Electron Microscope

@#Introduction: The compatibility of denture cleanser is crucial in the prevention of failure of adhesion between silicone soft liner and acrylic denture base, thus ensuring the durability of the prosthesis. This scanning electron microscope (SEM) study was to determine the mode of failure and measured the gap formation between silicone soft liners and Polymethylmethacrylate (PMMA) denture base after immersion in denture cleansers. Methods: A total of 135 specimens of PMMA denture base lined with three different silicone soft liners (GC Reline Soft, Mollosil and Tokuyama Sofreliner Tough) were immersed into denture cleansers (Polident® and Stearadent) daily and stored in distilled water at 37±1°C. Specimens were examined and sectioned at 2.5mm and 5.0mm from the margin after 1 day, 30 days and 90 days before analyzed. Results: No significant difference detected in the mode of failure and gap formation after one-day immersion. Adhesive failure was the commonest failure at the margin after 30 days (71.11%) and after 90 days (95.56%). However, 33.33% of specimens showed mixed failure at 5.0mm sectioned after 90 days. A significant difference of gap formation was demonstrated from Mollosil in Steradent at the margin and at 2.5 mm sectioned after 30 days and after 90 days (p<0.05). It was also observed at the margin and 5.0mm sectioned of specimens from Tokuyama in Steradent after 90 days of immersion (p<0.05). Conclusion: Specimen immersed in Steradent denture cleanser presented with wider gap formation as compared to Polident®, and adhesive failure is the commonest mode of failure.

The use of a liner under different bulk-fill resin composites: 3D GAP formation analysis by x-ray microcomputed tomography

Abstract Gap formation of composite resin restorations is a serious shortcoming in clinical practice. Polymerization shrinkage stress exceeds the tooth-restoration bond strength, and it causes bacterial infiltration within gaps between cavity walls and the restorative material. Thus, an intermediate liner application with a low elastic modulus has been advised to minimize polymerization shrinkage as well as gap formation. Objective: The purpose of this in vitro study was to assess gap formation volume in premolars restored with different bulk-fill composites, with and without a resin-modified glass-ionomer cement (RMGIC) liner, using x-ray micro-computed tomography (micro-CT). Methodology: Sixty extracted human maxillary premolars were divided into six groups according to bucco-palatal dimensions (n=10). Standardized Class II mesio-occluso-distal cavities were prepared. G-Premio Bond (GC Corp., Japan) was applied in the selective-etch mode. Teeth were restored with high-viscosity (Filtek Bulk Fill, 3M ESPE, USA)-FB, sonic-activated (SonicFill 2, Kerr, USA)-SF and low viscosity (Estelite Bulk Fill Flow, Tokuyama, Japan)-EB bulk-fill composites, with and without a liner (Ionoseal, Voco GmbH, Germany)-L. The specimens were subjected to 10,000 thermocycles (5-55°C) and 50,000 simulated chewing cycles (100 N). Gap formation based on the volume of black spaces at the tooth-restoration interface was quantified in mm3 using micro-computed tomography (SkyScan, Belgium), and analyses were performed. Data were analyzed using repeated-measures ANOVA and the Bonferroni correction test (p < 0.05). Results: The gap volume of all tested bulk-fill composites demonstrated that Group SF (1.581±0.773) had significantly higher values than Group EB (0.717±0.679). Regarding the use of a liner, a significant reduction in gap formation volume was observed only in Group SFL (0.927±0.630) compared with Group SF (1.581±0.773). Conclusion: It can be concluded that different types of bulk-fill composite resins affected gap formation volume. Low-viscosity bulk-fill composites exhibited better adaptation to cavity walls and less gap formation than did sonic-activated bulk-fill composites. The use of an RMGIC liner produced a significant reduction in gap formation volume for sonic-activated bulk-fill composites.

Effect of flowable composite or glass ionomer liners on shrinkage stress of a composite resin / Efecto de recubrimientos con resinas de baja viscosidad o ionómero vitreo sobre la tensión por contracción de una resina compuesta

ABSTRACT The aim of this study was to evaluate the effect of flowable composite or glass ionomer liners on the shrinkage stress of a restorative composite resin. Fifteen previously sandblasted metal boxes were attached to a universal mechanical testing machine (INSTRON 1011, Instron Corporation). Five of these boxes were filled with Filtek Z350 XT (FXT) Universal Restorative A2 (3M ESPE) (Group 1 or Control). Two further groups of 5 boxes were prepared by interposing a layer of Vitrebond Light Cure Glass Ionomer 3M ESPE (VGI) (Group 2 or G.I.) or Filtek Z350 XT Flowable Restorative A2 3M ESPE (FFR) (Group 3 or Flowable) between the box and the composite resin, completing with the same volume of composite as in Group 1. Upon activating lightcuring, the filled boxes mounted on the testing machine were videoed for 60 seconds (40 s photoactivation and 20 s postcuring), timed with a digital chronometer. Force values were recorded in newtons and converted into stress according to contact surface. Stress values were recorded every 10 s. Results were analyzed using repeated measures ANOVA. Mean and standard deviation in kPa (stress) recorded for each group were: Control group: 126.2 (30.8); G.I.: 48.4 (18); Flowable: 27.9 (19.5). Statistical analysis showed significant differences between the control group and the rest (p<0.01), with no significant difference between groups with glass ionomer liners and flowable resin liners (G.I. and Flowable). Under the experimental conditions of this study, it can be concluded that polymerization shrinkage stress can be reduced by the presence of a liner between the preparation and the restorative material.

RESUMEN El objetivo de este trabajo fue evaluar el efecto de la colocación de una capa de Composite flow o Ionómero vítreo sobre la tensión de contracción de un composite para restauración. Se utilizaron 15 cajas metálicas previamente arenadas y conectadas a la máquina universal para ensayos mecánicos (INSTRON 1011, Instron Corporation). Cinco de estas cajas (G1) se rellenaron con Filtek Z350 XT (FXT) Universal Restorative A2 3M ESPE. Al iniciar la activación de la unidad de curado se comenzaba a registrar con una cámara de video y un cronómetro digital desde el comienzo de la activación de la lámpara hasta 60 s después, registrando los valores post curado durante 20 s. Los valores de fuerza generados por la polimerización fueron registrados en newton de cada 10 s para los 15 ensayos. Los valores fueron convertidos en tensión de contracción según la superficie de contacto. Se realizaron además dos grupos de cajas (5 en cada una) en los cuales se colocaron una capa inicial de Vitrebond Light Cure Glass Ionomer 3M ESPE (VGI) (G2 o IV) y Filtek Z350 XT Flowable Restorative A2 3M ESPE (FFR) (G3 o Flow) y se completó con el mismo volumen de composite de las del GI. Los resultados obtenidos fueron analizados por medio de ANOVA para mediciones repetidas. La media y la desviación estándar en kPa (tensión o estrés de contracción) registrado para cada grupo fueron: Grupo control: 126.2 (30.8); IV: 48.4(18); Flow: 27.9(19.5). El análisis estadístico mostró diferencias estadística mente significativas entre el grupo control y el resto (p=0.00), pero no hubo diferencias significativas entre la presencia de Ionómero vítreo o Composite Flow (IV y Flow). En las condiciones experimentales de este trabajo puede concluirse que la tensión de contracción generada durante la polimerización puede ser disminuida por la presencia de algún material interpuesto entre la preparación y el composite restaurador.

Effect of liners and primers on tensile bond strength between zirconia and resin-based luting agent

PURPOSE: The effect of silica-based glass-ceramic liners on the tensile bond strength between zirconia and resin-based luting agent was evaluated and compared with the effect of 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primers. MATERIALS AND METHODS: Titanium abutments and zirconia crowns (n = 60) were fabricated, and the adhesive surfaces of the specimens were treated by airborne-particle abrasion. The specimens were divided into 5 groups based on surface treatment: a control group, 2 primer groups (MP: Monobond Plus; ZP: Z Prime Plus), and 2 liner groups (PL: P-containing Liner; PFL: P-free Liner). All specimens were cemented with self-adhesive resin-based luting agent. After 24-hour water storage and thermocycling (5,000 cycles, 5℃/55℃), the tensile bond strength was measured using a universal testing machine. Failure mode analysis and elemental analysis on the bonding interface were performed. The data were analyzed using Kruskal-Wallis test, Dunn's post hoc test, and Fisher's exact test. RESULTS: The liner groups and primer groups showed significantly higher tensile bond strengths than that of the control group (P < .05). PFL showed a significantly higher tensile bond strength than the primer groups (P < .05). The percentage of mixed failure was higher in the primer groups than in the control group (P < .001), and all the specimens showed mixed failure in the liner groups (P < .001). A chemical reaction area was observed at the bonding interface between zirconia and liner. CONCLUSION: The application of liner significantly increased the tensile bond strength between zirconia and resin-based luting agent. PFL was more effective than MDP-containing primers in improving the tensile bond strength with the resin-based luting agent.

Cementless Total Hip Arthroplasty Using Ceramic Femoral Head on Cross-Linked Ultra-High-Molecular Weight Polyethylene Liner in Patients Older than 65 Years: Minimum Five-Year Follow-Up Results / 대한정형외과학회잡지

PURPOSE: To evaluate the utility of ceramic-on-polyethylene articular bearing surface when cementless total hip arthroplasty is performed in patients older than 65 years through an analysis of the minimum five-year follow-up results using the ceramic femoral head and cross-linked polyethylene liner. MATERIALS AND METHODS: From March 2010 to September 2012, 51 patients (56 hips) who were older than 65 years were enrolled in this retrospective study. The mean age at surgery was 70.9±5.1 years old. A clinical assessment was analyzed using the Harris hip score. For the radiographic assessment, the cup inclination and anteversion, stem alignment, and wear amount were measured. The postoperative complications were also determined. RESULTS: The mean Harris hip score was improved from preoperative 48 points to postoperative 87 points (p < 0.05). The mean cup inclination was 40.9°±6.4° and the mean cup anteversion was 20.3°±8.1°. The mean cup anteversion of the elevated liner-used group (16 cases) was 14.3°±7.9° and the mean cup anteversion of the neutral liner used group (40 cases) was 22.4°±9.1° (p < 0.05). The mean stem alignment angle was 0° (range, varus 4°–valgus 4°). The mean linear wear amount was 0.458±0.041 mm and the average annual linear wear rate was 0.079±0.032 mm/yr. Six cases (10.7%) of intraoperative periprosthetic femoral fractures were encountered. CONCLUSION: Based on these results, the use of a ceramic-on-polyethylene articular bearing surface in elderly patients with cementless total hip arthroplasty is beneficial. On the other hand, careful effort is needed to prevent intraoperative periprosthetic femoral fractures.

A retrospective study on the application of cemented polyethylene liner technique in hip revision / 中国修复重建外科杂志

Objective: To evaluate the effectiveness of cemented polyethylene liner technique in hip revision. Methods: Based on inclusion criteria, the clinical data of 26 patients who were undergone hip revision between January 2011 and December 2013, were retrospectively reviewed. Among them, 14 cases were treated with isolated liner exchange (group A) and 12 cases were treated with cemented polyethylene liner technique (group B). There was no significant difference in gender, age, the time from primary total hip arthroplasty to revision, and the preoperative Harris score between 2 groups ( P>0.05). The post-operative Harris score and complications were compared between 2 groups, and X-ray findings of the hip joint were recorded to review the position of hip components. Results: All patients were followed up 4.4-6.4 years (mean, 5.4 years). Except for two femoral fractures during the revision (1 in each group), there was no other complication in 2 groups. The hip pain relieved and the lame gait corrected in 2 groups. The hip's function of 2 groups improved gradually after operation, with a better Harris score at 3 months and the best at the last follow-up, compared with preoperative scores ( P0.05). X-ray films showed no dislocation, aseptic loosening, and other interface related complication. Conclusion: For the cases without the chance to do change liner, cemented polyethylene liner technique has a good effectiveness. But restrict patient selection should be considered before hip revision.

Acetabulum Protrusion Following Ceramic Liner Fracture: A Case Report

@#Hip arthroplasty is an extremely satisfying treatment method for coxarthrosis which is in increasing use throughout the world. However, loosening of the prosthesis is a significant complication and to overcome this, ceramic liners are increasingly being selected. If the survival of ceramic surfaces is prolonged, there is a risk of fracture of the ceramic materials. New ceramic materials developed to overcome this problem are more resistant. The case presented here is of a patient in whom liner fracture developed following ceramic-ceramic hip arthroplasty. The ceramic femoral head was observed to have protruded into the defect created in the acetabular component. Acetabular revision was applied to the patient.

Application effect and safety analysis of streamlined liner of the pharynx airway anesthesia in painless fiberoptic bronchoscopy / 新乡医学院学报

Objective To analyze the application effect and safety of streamlined liner of the pharynx airway (SLIPA) anesthesia in painless fiberoptic bronchoscopy (FB).Methods Two hundred and eighty-two patients who undorwent FB examination in Kaifeng Second People's Hospital from January 2015 to January 2017 were selected and divided into observation group and control group,with 141 patients in each group.The patients in observation group were given SLIPA assisted anesthesia;the patients in control group were given endoscopic mask assisted anesthesia.The oxygen saturation (SpO2),systolic blood pressure (SBP),diastolic pressure (DBP) and heart rate (HR) of patients in the two groups were monitored.The changes of SBP,DBP and HR,the incidence of adverse reactions and the satisfaction of patient to the anesthesia were compared between the two groups.Results The fluctuation of HR,SBP and DBP of patients in the observation group was (3.52 ± 2.92) times · min-1,(7.04 ±5.30) mmHg(1 mmHg =0.133 kPa),(1.52 ± 1.63) mmHg respectively and in the control group was (5.52 ± 1.89) times · min-1,(30.12 ± 8.88) mmHg,(4.06 ± 5.78) mmHg respectively;the fluctuations of HR,SBP and DBP of patients in the observation group were significantly less than those in the control group(P ＜ 0.05).In the observation group,12 patients with cough,8 patients with abdominal distension,6 patients with pharyngeal pain,2 patients with SpO2 ≤90％,4 patients with SpO2 ＜ 85％;in the control group,57 patients with cough,32 patients with abdominal distension,47 patients with pharyngeal pain,28 patients with SpO2 ≤90％,19 patients with SpO2 ＜ 85％.The incidence of adverse reactions of patients in the observation group was significantly lower than that in the control group (x2 =27.10,61.82,41.59,72.46,87.75;P ＜0.05).The anesthesia satisfaction of patients in the observation group(97.87％) was significantly higher than that in the control group(82.98％) (x2 =29.97,P ＜ 0.05).Conclusion SLIPA assisted anesthesia has good clinical effect and safety in patients with painless FB.

Revision Total Hip Arthroplasty with Constrained Liner in Patients with Abductor Insufficiency / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate clinical and radiographic results of revision total hip arthroplasty with constrained liner in patients with abductor insufficiency. MATERIALS AND METHODS: In this study, 30 patients treated with constrained liner during revision total hip arthroplasty due to abductor insufficiency were evaluated after minimum 2-year follow-up. There were 14 men and 16 women and the mean follow-up period was 4.6 years. Re-dislocation and aseptic loosening of the implant were defined as a failure of the constrained liner. Harris hip score and ambulatory function were evaluated as a clinical parameter and osteolysis, aseptic loosening of the implant and other complications were evaluated as a radiologic parameter. RESULTS: During the follow-up period, there were 4 cases (13.3%) of constrained liner failure including two cases of re-dislocation and two cases of acetabular cup aseptic loosening. The average Harris hip score was improved from 38.3 points preoperatively to 73.4 points at last follow up. At the final follow-up, there were 20 cases (66.7%) of improvement in ambulatory function. There was 1 case of infection and 1 case of periprosthetic fracture. CONCLUSION: Use of a constrained liner during revision total hip arthroplasty showed satisfactory results for prevention of re-dislocation in patients with abductor insufficiency. However longer term studies on loosening of implants are needed.

Influence of ozone and paracetic acid disinfection on adhesion of resilient liners to acrylic resin

PURPOSE: The aim of this study was to evaluate the effect of paracetic acid (PAA) and ozone disinfection on the tensile bond strength (TBS) of silicone-based resilient liners to acrylic resins. MATERIALS AND METHODS: One hundred and twenty dumbbell shaped heat-polymerized acrylic resins were prepared. From the mid segment of the specimens, 3 mm of acrylic were grinded off and separated parts were reattached by resilient liners. The specimens were divided into 2 control (control1, control7) and 4 test groups of PAA and ozone disinfection (PAA1, PAA7, ozone1 and ozone7; n=10). While control groups were immersed in distilled water for 10 min (control1) and 7 days (control7), test groups were subjected to PAA (16 g/L) or ozone rich water (4 mg/L) for 1 cycle (10 min for PAA and 60 min for ozone) per day for 7 days prior to tensile tests. Measurements of the TBS were analyzed using 3-way ANOVA and Tukey's HSD test. RESULTS: Adhesive strength of Mollosil decreased significantly by application of ozone disinfection. PAA disinfection had no negative effect on the TBS values of Mollosil and Molloplast B to acrylic resin. Single application of ozone disinfection did not have any negative effect on TBS values of Molloplast B, but prolonged exposure to ozone decreased its adhesive strength. CONCLUSION: The adhesion of resilient liners to acrylic was not adversely affected by PAA disinfection. Immersion in ozonated water significantly decreased TBS of Mollosil. Prolonged exposure to ozone negatively affects adhesion of Molloplast B to denture base materials.

Liner effect on the bond strength of feldspathic ceramic to zirconia using a slow cooling protocol / Efecto del liner en la resistencia adhesiva de cerámica feldespática a la zirconia utilizando protocolo de enfriamiento lento

ABSTRACT. Introduction: the aim of this study was to compare the influence of a liner on veneering porcelain bond strength to two zirconia systems using a slow cooling protocol. Methods: twenty zirconia blocks were fabricated (12 x 11 x 4 mm), sintered, and layered with a veneering porcelain (5 x 11 x 4 mm, IPS e.max Ceram, Ivoclar Vivadent) using a slow cooling protocol. Four groups were evaluated: IPS e.max ZirCAD (Ivoclar Vivadent) with liner (IL) and without liner (IX), and Ecco-Zirconia (Amann Girrbach) with liner (EL) and without liner (EX) liner. Shear bond strength (SBS) test was conducted and failure modes were recorded. Results: the one-way ANOVA test yielded no significant statistical differences among the four groups (p = 0.662). The mean SBS values (±SD) in MPa were 15.2 (±1.7) MPa for EX, 15.3 (±2.0) MPa for EL, 16.4 (±4.2) MPa for IX, and 13.5 (±1.4) MPa for IL. All the samples showed a combined adhesive/cohesive failure. Conclusions: application of a liner did not alter the bond strength between veneering porcelain and zirconia when using a slow cooling protocol. No differences were found among the tested zirconia blocks.

RESUMEN. Introducción: comparar la influencia del Zir-liner sobre la resistencia adhesiva de cerámica feldespática a dos sistemas cerámicos de zirconia mediante un protocolo de enfriamiento lento. Métodos: se fabricaron 20 bloques de zirconia (12 x 11 x 4 mm), se sinterizaron y se aplicó cerámica de recubrimiento (5 x 11 x 4 mm, IPS e.max Ceram, Ivoclar Vivadent) utilizando un protocolo de enfriamiento lento. Se evaluaron cuatro grupos: IPS e.max ZirCAD (Ivoclar Vivadent) con liner (IL) y sin liner (IX), Ecco-Zirconia (Amann Girrbach) con liner (EL) y sin liner (EX). Se llevó a cabo la prueba de resistencia adhesiva (SBS) y se registraron los tipos de falla entre la cerámica y la zirconia. Resultados: one-way ANOVA no reveló diferencia estadísticamente significativa entre los cuatro grupos (p=0,662). Los valores promedios SBS (±SD) en MPa fueron 15,2 (±1,7) MPa para EX, 15,3 (±2,0) MPa para EL, 16,4 (±4,2) MPa para IX and 13,5 (±1,4) MPa para IL. En todas las muestras se observó una falla combinada adhesiva/cohesiva. Conclusiones: la aplicación del liner no alteró la fuerza adhesiva entre la cerámica feldespática y la zirconia utilizando un protocolo de enfriamiento lento. No se encontró diferencia entre los bloques de zirconia evaluados.

Biofilm formation on complete denture liners

AIM: To clinically evaluate biofilm growth on 4 liners in complete denture base surfaces of 20 geriatric patients. MATERIAL AND METHODS: Patients received new complete maxillary dentures prepared with 4 chambers (10x10x2 mm) in the tissue surface of acrylic denture base. Each of the 4 chambers was randomly filled with the following denture liners: Eversoft (M1); Kooliner (M2); GC Reline Extra Soft (M3); Elite Soft Relining (M4). Patients were randomly separated into 2 treatment groups: T1- sanitization with soft brush and dentifrice; T2- similar to T1 with daily immersion in cleansing chemical solution (Ortoform). Patients had 8 follow-up sessions over a 3-month period. The internal denture surface was stained with a dental plaque dye at each of the follow-up visits. Standardized photographs were taken, and biofilm growth was scored. Data were tabulated and submitted to Analysis of Variance. Means were compared by Tukey (p<0.05) and T tests. RESULTS: Kooliner (M2) means were significantly different from the others for both groups T1 and T2. Treatment 1 promoted higher biofilm growth scores than treatment 2. The highest score after treatment 1 was Kooliner (M2) and the lowest was Elite Soft Relining (M4). As for treatment 2, Eversoft (M1) was statistically different from Elite Soft Relining (M4). Again, Kooliner (M2) presented the highest score and Elite Soft Relining (M4) the lowest. Kooliner (M2) was statistically different from both GC Reline Extra Soft (M3) and Elite Soft Relining (M4). CONCLUSION: Of the materials and treatments studied, the best clinical selection for lower biofilm growth scores would be Elite Soft Relining (M4) with treatment 2.

The effect of thermocycling on nano-silver-incorporated silicone denture liner for Candida albicans adhesion / 实用口腔医学杂志

Objective:To evaluate the effect of thermocycling on nano-silver-incorporated silicone denture liner for Candida albicans (CA)adhesion.Methods:Specimens(1 0 mm ×1 0 mm ×3 mm)of silicone denture liner(control)and that incorporated with nano-sil-ver were prepared according to the manufacturer's direction.8 of the each kind of specimens were immersed in distilled water for 24 h at 37 ℃,and 8 were subjected to thermocycling for 4 000 cycles at temperatures ranging from (5 ±1 )℃to (55 ±1 )℃with a 60 s dwell time per temperature.In vitro CA adhesion assay was used to measure the levels of adherence to the specimens.Data were analysed sta-tistically.Results:Thermocycling increased CA adhesion to control specimens(P0.05 ).The adhesion of CA to nano-silver incorporated specimens was fewer than that to the controls with or wihout themocycling(P<0.01 ).Conclusion:Nano-silver incorporation may inhibit CA adhesion to silicone denture liner.Ther-mal cycling has no influence on C.albicans adhesion to silicone denture liner incorporated nano-sliver.

The effects of thermocycling on the tensile bond strength of silicone denture liner incorporated with silver-nano-particles / 实用口腔医学杂志

16 standered acrylic resin blocks with silicone resilient denture liner(10 mm ×8 mm ×3 mm)incorporated with nano-silver par-ticles at 5% (m/m,by dry wet)in-between were prepared.8 blocks were immersed in distilled water for 24 h at 37 ℃ as the controls (group 1).Another 8 were thermocycled for 4 000 cycles(group 2).16 acrylic resin bars were thermal cycled for 4 000 cycles.Then they were processed exactly as the control group (group 3).Tensile bond strength of the specimens was measured by a universal testing machine. The bond strength values(MPa)of group 1,2 and 3 were 2.683 ±0.435,2.179 ±0.633 and 1.460 ±0.566 respectively(group 1 vs 2,P>0.05;group 3 vs 1 or 2,P<0.05).The failure mode of the blocks in group 1 and 2 was mainly cohesive failure,in group 3 adhesion fail-ure.