Sealant Treatment Research Articles

Comparison of the clinical performance of self-adhering flowable composite and resin-based pit and fissure sealant: a randomized clinical trial in pediatric patients

BackgroundSelf-adhering flowable composites are an innovative step in reducing the chair time of pit and fissure sealant treatment. This study aimed to compare the clinical performance of self-adhering flowable composite (SELF-ADH) and resin-based pit and fissure sealant (RBs).MethodsThis is a double-blinded, randomized, split-mouth clinical trial conducted on 80 fully erupted permanent mandibular first molars from 40 children aged 6 to 12 years. For each participant, two permanent molars were randomly treated with SELF-ADH or RB. All sealants were assessed at 3, 6, and 12-month follow-ups considering retention, marginal integrity, marginal discolouration, colour matching, surface texture, and caries recurrence. To analyse the data, logistic regression and Fisher’s exact tests were used (significance level P < 0.05).ResultsAt the 12-month follow-up, the number of fully retained sealants in the SELF-ADH group was significantly higher than that in the RB group (P < 0.001). Also, The success rate of marginal integrity in the SELF-ADH group was significantly greater than the the RB group (P = 0.031), while the rate of sealant marginal discolouration was higher in the RB group (P < 0.001). The incidence of recurrent caries in teeth with partial loss of sealant in both groups (P = 0.004, P < 0.001) increased significantly over time.ConclusionThe retention and marginal integrity of the self-adhering flowable composite were significantly greater than those of the resin-based sealant. Therefore, due to the small number of work steps, flowable self-adhering composites can be used as alternatives to resin-based pit and fissure sealants.Trial registrationThis study was approved by the Ethics Committee of Kerman University of Medical Sciences with the code IR.KMU.REC.1399.556 and Iraninan Registry of Clinical Trials (IRCT) code IRCT20180521039763N4, as well as full compliance with the Declaration of Helsinki.

The Impact of Rubber Dam Association With Physiological Stress Parameters on Children of 7-10 Years Undergoing Pit and Fissure Sealant Treatment: An In-Vivo Study.

Introduction Anxiety is an emotion representing apprehension towards an unknown stimulus or situation. Rubber dam application during dental procedures in children makes the treatment more comfortable and acceptable as it gives them a psychological feeling that treatment is being carried out outside the oral cavity.The prime objective of this study was to evaluate and compare physiological parameters, which include pulse rate, arterial oxygen saturation level, blood pressure, and respiratory rate before and after rubber dam isolation. Material and methods The study consisted of 30 children patients of 7-10 years, comprised of 14 females and 16 males with a mean age of 8.15 ± 0.93 years. The study was a 'split mouth' clinical design study, where 60 sites in 30 patients (two sites in each patient) were used. The selected sites were divided into two groups by a convenience sampling method and were categorized as Group-I (control group - 30 sites were treated with pit and fissure sealants under cotton roll and saliva ejectors on mandibular right permanent first molar) and Group-II (study group - 30 sites were treated with pit and fissure sealants underrubber dam isolationon mandibular left permanent first molar). Results Rubber dam application reduced different physiological parameters of stress such as pulse rate, systolic and diastolic blood pressure, and respiratory rate at different intervals from the baseline values. Rubber dam and cotton roll applications have no significant effects on oxygen saturation levels at different intervals in healthy individuals. From statistical analysis, it was evident that a statistically significant difference was evident between the control and experimental groups (P value < 0.005). Conclusion It is confirmed in this study that rubber dam reduces different physiologic parameters of stress. After the application of the rubber dam, children's pulse rate, systolic and diastolic blood pressure, and respiratory rate were reduced. Clinical significance The study highlights the imperative role of rubber dam isolation in improving dental and medical effectiveness. In addendum to this, our research promotes the clinical use of rubber dams in pediatric dentistry.

Changes in the Perceptions of Oral Symptoms Due to COVID-19 in Korean Adolescents.

This study investigated the oral symptoms and subjective health perceptions of Korean adolescents due to COVID-19. Data from the 17th Korea Youth Risk Behavior Survey (KYRBS; 2021) were analyzed, and 54,848 Korean middle and high school students were included in the study. Frequency, cross-tabulation, and logistic regression analyses were performed using IBM SPSS (v. 22.0; IBM Corp., Armonk, NY, USA). Statistical significance was set at p < 0.05. The survey results on subjective health perception showed that 64.8% considered themselves "healthy", 26.1% rated themselves "moderate" in health, and 9.26% rated themselves "unhealthy." When asked about brushing their teeth after lunch at school, students answered "no" more frequently than "yes". Participants provided significantly different responses to questions related to receiving "sealant treatment", "having broken teeth", "experiencing tooth pain when eating", "having throbbing tooth pain", and "having pain and bleeding in gums". Regarding the relationship between oral symptoms and subjective health perceptions due to COVID-19, students perceived themselves as healthy when they had no throbbing tooth pain, risk of pain, bleeding in the gums, or symptoms of toothache when eating. Results reveal a relationship between oral symptoms and subjective health perceptions due to COVID-19. Thus, appropriate oral health management for adolescents is needed in response to the COVID-related changes.

Peningkatan Kesehatan Gigi dan Mulut Melalui Revitalisasi Usaha Kesehatan Gigi Sekolah di SDN Pasar Kamis 2 Kabupaten Banjar

Pasar Kamis 2 elementary school is one of the elementary schools in Kertak Hanyar District that has not implemented a phase III school dental health program, so it is necessary to revitalize the school dental health program. The revitalization of school dental health programs aims to revive promotional programs for dental and oral health in elementary schools. The method applied for this community service activity is by carrying out promotional activities in the form of teacher training for school dental health businesses, training for little doctors, health promotion through the media snakes and ladders and the song SIGIBER, as well as joint toothbrushing activities. Preventive activities carried out include carrying out dental and oral health screening and carrying out fissure sealant treatment and atraumatic restorative treatment based on the results of the screening. Evaluation of community service activities is carried out by measuring the results of pretest and posttest students' knowledge and analyzing the provision of preventive measures to students. The results of this service show that there is a difference in knowledge before and after being given health promotion interventions, as well as an improvement in students' dental and oral health after preventive measures are given in the form of pit and fissure sealants and atraumatic restorative treatment. Revitalization of school dental health businesses is important so that promotional activities for dental and oral health in the school environment are not neglected so that they can improve dental and oral health and school children's achievement in learning.

Assessment of implementation of the caries management by risk assessment philosophy in a dental school.

This cross-sectional study assessed the implementation of documenting a baseline caries risk assessment (CRA) of patients seen by predoctoral dental students and its association with the presence of caries risk management (CRM) treatment. A convenience sample of 10,000 electronic axiUm patient records at Tufts University School of Dental Medicine was retrospectively assessed for the presence or absence of a completed CRA and CRM after IRB approval following predetermined inclusion and exclusion criteria. The CRM variables (nutrition counseling, sealant, fluoride) were identified by procedure codes that were completed by the student. Associations were assessed via the chi-square test, Kruskal-Wallis test (with Dunn's test and the Bonferroni correction used in post-hoc tests) and Mann-Whitney U test. Most patients (70.5%) had a CRA completed. However, only 24.9% (out of the 7045 patients with a completed CRA) received CRM, while 22.9% of the 2,955 patients without a CRA received CRM. The difference between the groups with and without a completed CRA in terms of the percentage receiving CRM was not clinically significant. Significant associations were found between a completed CRA and in-house fluoride treatment (p=.034) and between a completed CRA and sealant treatment (p=.001). Patients with higher baseline CRA levels (i.e., greater risk) were more likely to have CRM (16.9% of the 785 patients at low risk, 21.1% of the 1282 patients at moderate risk, 26.3% of the 4347 patients at high risk, and 32.6% of the 631 patients at extreme risk). The association between these two variables was significant (p<.001). There is evidence that students were mostly compliant with completing a CRA for most patients; however, there is a deficiency in implementation of CRM approach to help support dental caries management, and there is still much room for improvement.

Basic research for the development of quality measures of oral care in Korea

The aims of this study were to evaluate quality indicators that can be applied to the dental care delivery system in Korea. This study was performed with a three-step process. Firstly, authors searched for quality indica-tors developed in dentistry field. Among them, 80 quality indicators were selected as the indicators that used indental institutions, and then 33-item preliminary list was extracted through evaluation by 9 experts consisted of dental clinicians and professors (college of dentistry and department of dental hygiene). Based on this 33-item preliminary list, a Delphi process was conducted twice by a stakeholder group consisting of 17 panels (dentists, dental hygienists, dental technicians, professors of dental colleges, and dental hygiene professors). Each item of the preliminary list was classified into 5 domains of importance, relevance, feasibility, reliability, and sensitiv-ity. The panels were asked to rate from 0 to 3-point (very unnecessary - very appropriate) to the 5 domains of all items. As a result, the sealant treatment item received the most consent, and the item of whether unnecessary antibiotics is prescribed received the lowest preference. Among the 33 items, the items that received a score of 2.5 or higher were sealant, brushing, fluoride application, caries prevention, periodontal management, regularcheck-up, continuity of treatment, and evaluation of current symptoms. This study was performed as basic re-search. Based on international consensus on the definition of the quality of oral health care, development of newmeasures is necessary to produce quality indicators that suitable for the dental setting in Korea.

A 5-year clinical follow-up of the efficacy of proximal sealing in high caries risk children

ObjectiveThe aim of the present study was to evaluate, after 5 years, the efficacy of proximal microinvasive sealing of permanent teeth on the risk for caries lesion development. MethodsChildren aged 8 to 10 y at baseline, at high caries risk, were studied. In the preventive (P) group the children had caries lesions on the distal surface of primary second molars (05d) but sound mesial surfaces of the approximating permanent first molars (6m). In the therapeutic (T) group the children had initial caries lesions on 6m that abutted lesions on 05d. Each child in the two groups had one 05d/6m pair. Using a split-mouth design, one 6m surface in each pair was randomly assigned to receive sealing while the other pair served as an unsealed control. ResultsOf the 61 children at baseline 42 could be blindly examined clinically and radiographically both at baseline and after 5 years. In the P group, 8 of 28 (28.6%) sealed and 15 of 28 (53.6 %) unsealed sound 6m surfaces had developed caries lesions (p = 0.04). In the T group, the progression of the carious lesions on 6m was observed in 4 of 14 sealed (28.6%) and 8 of 14 (57.1%) unsealed caries control surfaces (p = 0.29). Pooling the data from the two groups, the difference between sealed and non-sealed surfaces was significant (p = 0.013). ConclusionBoth preventive and therapeutic sealant to 6m adjacent to a lesion on 05d has effectiveness in caries reduction in high caries risk children Clinical SignificanceThe beneficial effect of sealing is observed for at least 5 years after a single sealant treatment.

The Influence of Polymeric Sealing Treatment on the Wear Performance of PEO Coating Deposited on AZ31 Mg Alloy

A plasma electrolytic oxidation (PEO) coating fabricated on AZ31 Mg alloy was sealed with polymeric sealant. The sealant penetrated into the PEO coating and filled the micropores and microcracks of the coating. The effect of the sealant treatment on the sliding wear behavior of the PEO coating was investigated by systematically varying the axial wear loads applied onto the unsealed and sealed PEO coatings. The results of the sliding wear tests revealed that the polymeric sealing treatment enhanced the wear resistance of the Mg-based PEO coating by reducing the wear rate and by improving the load-bearing capacity.

Evaluation of the success rate of pit and fissure sealants on first molars: 12months follow-up study.

Dental caries by far is the most prevalent concern of the preadolescents and adolescents in dental clinics. Despite the provision of local fluoride, the occlusal surfaces of teeth are susceptible to dental caries. Pit and fissure sealant therapy is a preventive method to decrease dental caries in permanent teeth. The present study aimed to evaluate the success of fissure sealant treatments of first molar teeth, at 3, 6 and 12months follow-ups. Sixty-five children were randomly selected. The subjects had already received fissure sealants in the department of public health dentistry. Demographic data, including age and gender, sealant failure and the type of failure were recorded in the relevant checklists. Feigal criteria were used to evaluate the success or failure of fissure sealant treatments. Overall success rate was 74.3% for 1year. Evaluation of the failure rate showed that at the 3-month interval, 20.6% of the sealants exhibited failure (57.1% due to margin discoloration and 42.9% due to lack of margin adaptation). 28.6% of the sealants failed at the 6-month (75% due to marginal discoloration and 25% due to anatomical form) and 41.2% failed at the 12-month interval (57.1% due to marginal discoloration and 42.9% due to the lack of margin adaptation). The total failure rate of fissure sealant failures after 1year was 27.7%. The most frequent reason for the failure of fissure sealants was marginal discoloration.

Release of Bisphenol A from Pit and Fissure Sealants According to Different pH Conditions.

Changes in intraoral pH can cause changes in the chemical decomposition and surface properties of treated resin-based pits and fissure sealants (sealant). The purpose of this study is to evaluate the release of bisphenol A (BPA) from sealants under three different pH conditions over time. The test specimen was applied with 6 sealants 5 mg each on a glass plate (10 × 10 mm) and photopolymerized. The samples were immersed for 10 min, 1 h, and 24 h in solutions of pH 3.0, 6.5, and 10.0 at 37 °C. BPA release was measured using a gas chromatography-mass spectrometer. A statistical analysis was performed by two-way ANOVA and one-way ANOVA to verify the effect of pH conditions and time on BPA release. The BPA concentration in the pH 3.0 group was higher at all points than with pH 6.5 and pH 10.0 (p < 0.05), and gradually increased over time (p < 0.05). As a result, it was confirmed that low pH negatively influences BPA release. Therefore, frequent exposure to low pH due to the consumption of various beverages after sealant treatment can negatively affect the sealant’s chemical stability in the oral cavity.

Pit-and-fissure sealants on primary molars are a cost savings

BackgroundIn this study, the authors examine the cost-effectiveness of light-polymerized resin-based fluoride sealants on primary molars in high caries risk children younger than 6 years. MethodsThe authors examined the cost-effectiveness of pit-and-fissure sealant (PFS) treatment on primary molars by comparing sealed and unsealed molars treated in the outpatient clinic or operating room. Using 1,884 primary molars followed over a 5-year period, the authors used a mixed-effects regression model to estimate the probability of caries development. They used restricted means to estimate years free of caries for carious molars. They used a decision tree to address uncertainty due to PFS treatment failure, predict the expected value associated with each strategy, and estimate the incremental cost-effectiveness ratio using a 3% discount rate to adjust future cost and outcomes to present value. ResultsOver 5 years, the cost of care was $90 for unsealed molars and $75 for sealed molars. Unsealed molars remained caries free for 4.32 years compared with 4.85 years in sealed molars. The cost-effectiveness of PFS treatment was dominant, leading to a savings of $25 for each caries-free year gained and overall savings of $742 million for the United States dental health system over a 5-year period. ConclusionsPFS treatment is associated with cost savings and a delay in caries development and should be considered in children with high caries risk. Practical ImplicationsPolicy makers should consider reimbursement of PFS treatment on primary molars in high caries risk children.

Effectiveness of Sealants Treatment in Permanent Molars: A Longitudinal Study.

BackgroundOur study gives a clear result about sealants treatment in preventing dental caries manifestation and reducing its prevalence in children aged 6–11 years old.Aim and objectiveThis study aims to compare and evaluate the progress of dental caries in the first and second permanent molars and also to evaluate, within a period of 24 months, the clinical effects of dental sealants, used in the treatment of occlusive cavities, among children 6–11 years old.Materials and methodsParticipants: The overall sample was composed of 120 children, to whom we randomly chose 480 posterior teeth, which were divided into two groups. Intervention: The first group was the control group with 240 untreated teeth, while the second group had an equal number of teeth, which underwent the sealant treatment. The study participants were evaluated within the periods 0, 6, 12, 18, and 24 months. The study participants were checked every 6 months. Basic design: This observational, analytical, and descriptive research was designed as a longitudinal study. The study started in January 2019 and ended in January 2020. The study was conducted in five dental clinics in the city of Vlore, Albania.ResultsAfter 24 months of observation, we noticed that the number of dental caries in the untreated group is three times higher than the number of dental caries in the treated group. In the group of teeth treated with sealant, 189 (78.8%) teeth remained unaffected by dental caries. The present study showed that there is a significant correlation between period and caries manifestation (p < 0.05). It also proved that sealant treatment is an important measure and it is highly significant in the caries reduction (p = 0.000).ConclusionThis study proved that sealant treatment is highly successful in reducing dental caries. In the future, it is worthwhile to go further in this research.Clinical significanceDental caries is a problem in children aged 6–11 years old and not only. That is why this study recommends that sealants treatment should be used to prevent and reduce the prevalence of dental caries.How to cite this articleCanga M, Malagnino G, Malagnino VA, et al. Effectiveness of Sealants Treatment in Permanent Molars: A Longitudinal Study. Int J Clin Pediatr Dent 2021;14(1):41–45.

Analysis of the Characteristics of Children and Adolescent Patients Received Sealant after National Health Insurance Coverage using Big Data

The purpose of this study was to analyze the characteristics of pediatric and adolescent patients who received sealant after health insurance coverage based on demographic factors such as gender, age, insurance type, care institution and region.&lt;br/&gt;Patient Sample Data from the Health Insurance Review and Assessment Service were used for this study. A total of 8,454,636 patients’ data were obtained from 2010 to 2017. Of these, 114,680 patients got sealant treatment. Females were more likely to receive sealant treatment than males. 5 - 9 year age group showed the highest number of patients and proportion of treatment. Patients with health insurance were more likely to receive pit and fissure sealant treatment compared to patients with medical aid program. The number of sealant patients and the proportion of sealant treatment were the highest in dental clinics, followed by dental hospitals and public health centers. The number of sealant patients were the highest in Gyeonggi and proportion of sealant patients were the highest in Jeonbuk.

Comparison of dental treatments performed under general anesthesia for healthy and disabled children

This study aimed to assess and compare the type of dental procedures performed under general anesthesia for healthy and disabled children. This descriptive, cross-sectional study evaluated 361 dental records of children who received dental treatments under general anesthesia in the operating room of Torabinejad Research Center during 2011-2013. Patients with mental or physical disability were categorized as disabled. The age and gender of patients, number of treated teeth, duration of general anesthesia, type of tooth, and type of dental treatment such as extraction, pulp therapy, placement of stainless steel crowns, composite restoration, preventive resin restoration (PRR), fissure sealant treatment, and fluoride therapy were separately recorded for the healthy group and patients with disability. Data were analyzed using one-way ANOVA, and independent sample t-test at P < 0.05 level of significance. Of 361 patients, 263 patients were healthy and 102 patients had disability. Of all disabled children, 48% had physical and 52% had mental disability. Among patients with physical disability, allergy (40%), followed by cardiovascular diseases (26%) were the most common. Mental retardation (54%) followed by cerebral palsy (10%) were the most common mental disabilities. Number of extracted teeth was significantly higher in disabled children (P = 0.006). Furthermore, disabled children received significantly lower PRR (P = 0.015), fissure sealant treatment (P = 0.003), fluoride therapy (P = 0.002), and pulp therapy (P < 0.001) compared with healthy children. Tooth extraction has a higher frequency in disabled children; while, attempts are made to preserve the teeth as much as possible in healthy children.

A Comparative Analysis of the Duration and Cost of Treatment Between Glass Ionomer and Resin Based Fissure Sealants among Children in Benin City, Nigeria

Background: Dental service utilization in children is reduced as a result of long treatment times and prohibitive cost of treatment. This may result in an increase in early childhood caries and subsequent premature tooth loss. Fissure sealants are a preventable method in the management of dental caries but the cost may be a barrier to early treatment.&#x0D; Aim: To compare the duration and cost of sealant treatment between glass ionomer and resin based fissure sealants among children in Benin City,Nigeria.&#x0D; Materials and Methods: All occlusal surfaces of the lower permanent first molars (2 teeth each in a total number of 50 children) were sealed andincluded in the study (n=100). A split-mouth design was used in which a light cure Bis-GMA resin-based sealant was compared with a glass-ionomersealant. They were then randomly placed in 50 matched contralateral pairs of permanent first molar teeth and a stop watch used to record the duration of placement. The cost of treatment was calculated by dividing the cost of the sealant kit with the total number of sealed occlusal surfaces. Statistical analysis was done using Statistical Package for Social Sciences version 21.0 with the chi square test for determination of variables. Probability values of p&lt;0.05 were considered statistically significant.&#x0D; Results: The duration of sealant treatment using resin based sealant ranged from 235 to 446 seconds (mean time 318.86 +55.54 secs); while theduration of sealant treatment using glass ionomer based sealant ranged from 238 to 360 seconds (a mean time 292.57 +33.56 secs); and this wasstatistically significant (P&lt;0.001). The cost of sealing a tooth surface using resin sealant (Clinpro®) was five hundred and seventy naira only. Similarly, the cost of sealing a tooth surface using glass ionomer based sealant (GC Fuji triage®) was eight hundred and forty naira only.&#x0D; Conclusion: Less chairside time is required for sealant treatment using glass ionomer than resin based sealant for fissure sealing procedures. The use of resin based fissure sealant is relatively cheaper when compared with glass ionomer based sealant&#x0D;

Measuring sealant placement in children at the dental practice level

BackgroundAlthough sealants are an established and recommended caries-preventive treatment, many children still fail to receive them. In addition, research has shown that existing measures underestimate care by overlooking the sealable potential of teeth before evaluating care. To address this, the authors designed and evaluated 3 novel dental electronic health record–based clinical quality measures that evaluate sealant care only after assessing the sealable potential of teeth. MethodsMeasure I recorded the proportion of patients with sealable teeth who received sealants. Measure II recorded the proportion of patients who had at least 1 of their sealable teeth sealed. Measure III recorded the proportion of patients who received sealant on all of their sealable teeth. ResultsOn average, 48.1% of 6- through 9-year-old children received 1 or more sealants compared with 32.4% of 10- through 14-year-olds (measure I). The average measure score decreased for patients who received sealants for at least 1 of their sealable teeth (measure II) (43.2% for 6- through 9-year-olds and 28.4% for 10- through 14-year-olds). Fewer children received sealants on all eligible teeth (measure III) (35.5% of 6- through 9-year-olds and 21% of 10- through 14-year-olds received sealant on all eligible teeth). Among the 48.5% who were at elevated caries risk, the sealant rates were higher across all 3 measures. ConclusionsA valid and actionable practice-based sealant electronic measure that evaluates sealant treatment among the eligible population, both at the patient level and the tooth level, has been developed. Practical ImplicationsThe measure developed in this work provides practices with patient-centered and actionable sealant quality measures that aim to improve oral health outcomes.

Microleakage of a Self-Adhesive Flowable Composite, a Self-Adhesive Fissure Sealant and a Conventional Fissure Sealant in Permanent Teeth with/without Saliva Contamination

Objectives: Application of fissure sealants is a practical method for prevention of occlusal pit and fissure caries. Microleakage is an important factor affecting the success of fissure sealant treatment. This study aimed to assess the microleakage of a self-adhesive flowable composite, a self-adhesive fissure sealant and a conventional fissure sealant in permanent teeth with/without saliva contamination.&#x0D; Materials and Methods: This in vitro, experimental study evaluated 108 extracted human third molars, which were randomly divided into six groups (n=18) of control, Denu-Seal conventional fissure sealant applied on etched enamel with/without saliva contamination, Vertise Flow self-adhesive flowable composite applied on rinsed and dried enamel with/without saliva contamination and Prevent Seal self-adhesive fissure sealant applied on rinsed and dried enamel with/without saliva contamination. Microleakage was assessed using the dye penetration technique and subsequent observation of samples under a stereomicroscope. Data were analyzed using the Kruskal-Wallis and Tukey’s test.&#x0D; Results: Microleakage of the conventional fissure sealant with/without saliva contamination was significantly lower than that of other groups (P&lt;0.05).&#x0D; Conclusion: Microleakage of the conventional fissure sealant is less than that of self-adhesive fissure sealant and self-adhesive composite, irrespective of saliva contamination.

Microleakage of a Self-Adhesive Flowable Composite, a Self-Adhesive Fissure Sealant and a Conventional Fissure Sealant in Permanent Teeth with/without Saliva Contamination.

Objectives:Application of fissure sealants is a practical method for prevention of occlusal pit and fissure caries. Microleakage is an important factor affecting the success of fissure sealant treatment. This study aimed to assess the microleakage of a self-adhesive flowable composite, a self-adhesive fissure sealant and a conventional fissure sealant in permanent teeth with/without saliva contamination.Materials and Methods:This in vitro, experimental study evaluated 108 extracted human third molars, which were randomly divided into six groups (n=18) of control, Denu-Seal conventional fissure sealant applied on etched enamel with/without saliva contamination, Vertise Flow self-adhesive flowable composite applied on rinsed and dried enamel with/without saliva contamination and Prevent Seal self-adhesive fissure sealant applied on rinsed and dried enamel with/without saliva contamination. Microleakage was assessed using the dye penetration technique and subsequent observation of samples under a stereomicroscope. Data were analyzed using the Kruskal-Wallis and Tukey’s test.Results:Microleakage of the conventional fissure sealant with/without saliva contamination was significantly lower than that of other groups (P<0.05).Conclusion:Microleakage of the conventional fissure sealant is less than that of self-adhesive fissure sealant and self-adhesive composite, irrespective of saliva contamination.

Life cycle impact assessment of corrosion preventive designs applied to prestressed concrete bridge decks

Abstract Chloride corrosion of reinforcing steel in concrete structures is a major issue in the construction sector due to economic and environmental reasons. Assuming different prevention strategies in aggressive marine environments results in extending the service life of the exposed structures, reducing the maintenance actions required throughout their operation stage. The aim of the present study is to analyze the environmental implications of several prevention strategies through a life cycle assessment using a prestressed bridge deck as a case study. The environmental impacts of 15 prevention alternatives have been evaluated when applied to a real case of study, namely a bridge deck exposed to a chloride laden surrounding. The Eco-indicator 99 methodology has been adopted for the evaluation of the impacts. As some of the alternatives involve the use of by-products such as fly ash and silica fume, economic allocation has been assumed to evaluate their environmental impacts. Results from the life cycle analysis show that the environmental impacts of the chloride exposed structure can be reduced significantly by considering specific preventive designs, such as adding silica fume to concrete, reducing its water to cement ratio or applying hydrophobic or sealant treatments to its surface. In such scenarios, the damage caused to the environment mainly due to maintenance operations and material consumption can be reduced up to a 30–40% of the life cycle impacts associated to a conventional design. The study shows how the application of life cycle assessment methodologies can be of interest to reduce the environmental impacts derived from the maintenance operations required by bridge decks subjected to aggressive chloride laden environments.

Can a standardised Ventilation Mechanical Test for quantitative intraoperative air leak grading reduce the length of hospital stay after video-assisted thoracoscopic surgery lobectomy?

We standardised a Ventilation Mechanical Test (VMT) after video-assisted thoracoscopic surgery (VATS) lobectomy that classifies intraoperative alveolar air leaks (IOAALs) in mild, moderate and severe. We assumed that mild IOAALs (<100 mL/min) are self-limiting, whereas severe IOAALs (>400 mL/min) must be treated. An IOAAL between 100 and 400 mL/min was defined moderate and constituted the study population of a prospective multicentre randomised trial on the use of a polymeric biodegradable sealant (ProgelTM Pleural Air Leak Sealant, Bard Davol, USA) in case of moderate IOAAL compared with no treatment. We assumed that the standardised VMT allows to accurately selected patients needing treatment, thus limiting unnecessary sealant use. We analysed data of the randomised trial to assess the cost-effectiveness of Progel treatment in VMT selected patients. This is a multicenter randomised controlled trial. Patients with moderate IOAAL were randomised to Progel (group A) or "no treatment" (group B).The primary efficacy endpoint of the study was the postoperative duration of air leakage. The secondary outcome measures included: mean time to chest drain removal, mean length of hospitalisation, the percentage of postoperative complications occurring within two months, and cost of treatment. Between January 2015 and January 2017, 255 VATS lobectomies were performed in 4 centres, 55 met the inclusion criteria, and they were randomly assigned to 2 different groups (28 in the Progel and 27 in the control group). The mean air leakage duration was statistically different between the two groups: in the group A was 1.60 vs. 5.04 days in group B (P<0.001). The average duration of chest drainage was statistically shorter in group A than in the control group (4.1 vs. 6.74 days; P=0.008). The mean time to hospital discharge was also statistically shorter in group A than in group B (5.75 vs. 7.85 days, P=0.026). In the Progel group, a statistically significant reduction of hospitalisation costs compared with the control group was observed (Progel group =12,905₤, Control group =39,690₤; P<0.001). Our standardised VMT helps in reducing the length of hospital stay after VATS lobectomy because in case of IOAALs between 100 and 400 mL/min the use of ProgelTM significantly reduces postoperative air leak, time to drain removal and length of hospitalisation compared with no treatment. This shorter hospital stays results in significant cost saving benefits. Selection of patients with standardised VMT is essential to limit unnecessary intraoperative sealant treatments, thus contributing to limit the costs.