scholarly journals Fracture resistance of veneers in premolars

2018 ◽  
Vol 12 (02) ◽  
pp. 191-198 ◽  
Author(s):  
Ludmilla Azevedo Linhares ◽  
Larissa Fernanda Pottmaier ◽  
Guilherme Carpena Lopes
Keyword(s):  
Fracture Resistance ◽  
Composite Resin ◽  
Lithium Disilicate ◽  
Mean Values ◽  
Significant Difference ◽  
Mode Of Failure ◽  
The Mean ◽  
Tooth Preparation ◽  
Post Hoc ◽  
One Way Anova

ABSTRACT Objective: The purpose of the study was to compare the fracture resistance of ceramic veneers and composite resin veneers with and without dental preparation. Materials and Methods: Forty freshly extracted mandibular premolars were selected and randomly assigned into four groups (n = 10): Group NPR = no dental preparation and direct veneer with 0.2 mm thick composite resin (Amelogen Plus, Ultradent); Group NPC = no dental preparation and 0.2 mm thick lithium disilicate ceramic veneer (IPS e.max Press, Ivoclar Vivadent); Group P2C = Tooth preparation of 0.2 mm and 0.2 mm thick ceramic veneer (IPS e.max Press); and Group P5C = Tooth preparation of 0.5 mm and 0.5 mm-thick ceramic veneer (IPS e.max Press). In all groups, the restorations covered 1 mm of the occlusal surface of the buccal cusp, and the thickness of this area was the same of the buccal area (0.2 mm or 0.5 mm). After the luting procedure, all groups were thermocycled (10,000 cycles, 5°C–55°C) and subjected to fracture resistance test under compression (Instron 4444 with a crosshead speed of 0.5 mm/min). The mode of failure analysis was performed under a ×10 magnification. Data were subjected to one-way ANOVA and Duncan's post hoc test (P < 0.05). Results: The mean fracture resistance (men ± standard deviation) was NPR = 690.33 ± 233, NPC = 790.52 ± 408, P2C = 1131.34 ± 341, and P5C = 983.56 ± 202. There were significant differences of the fracture resistance values between all groups (P = 0.013). NPR and NPC groups showed mean values of fracture resistance significantly lower than P2C. However, P5C presented intermediate values without a significant difference from the other groups. The mode of failure for all groups was mixed (60%), cohesive failures (20%), root failures (15%), and adhesive failures (5%). Conclusion: Minimally invasive tooth preparation (0.2-mm) allowed to achieve higher fracture resistance in premolars restored with lithium disilicate ceramic veneers. Attention should be given to the 0.5 mm preparation since catastrophic fractures only happened when this preparation depth was performed.

scholarly journals Fracture resistance of immature teeth filled with mineral trioxide aggregate, bioaggregate, and biodentine

2016 ◽  
Vol 10 (02) ◽  
pp. 220-224 ◽  
Author(s):  
Emre Bayram ◽  
Huda Melike Bayram
Keyword(s):  
Fracture Resistance ◽  
Mineral Trioxide Aggregate ◽  
Mean Values ◽  
Root Canals ◽  
Immature Teeth ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Post Hoc ◽  
Group 1

ABSTRACT Objective: The purpose of this study was to evaluate fracture resistance of teeth with immature apices treated with coronal placement of mineral trioxide aggregate (MTA), bioaggregate (BA), and Biodentine. Materials and Methods: Forty-one freshly extracted, single-rooted human premolar teeth were used for the study. At first, the root length was standardized to 9 mm. The crown-down technique was used for the preparation of the root canals using the rotary ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) of F3 (30). Peeso reamer no. 6 was stepped out from the apex to simulate an incompletely formed root. The prepared roots were randomly assigned to one control (n = 5) and three experimental (n = 12) groups, as described below. Group 1: White MTA (Angelus, Londrina, Brazil) was prepared as per the manufacturer's instructions and compacted into the root canal using MAP system (Dentsply Maillefer, Ballaigues, Switzerland) and condensed by pluggers (Angelus, Londrina, Brazil). Group 2: The canals were filled with DiaRoot-BA (DiaDent Group International, Canada). Group 3: Biodentine (Septodont, Saint Maur des Fosses, France) solution was mixed with the capsule powder and condensed using pluggers. Instron was used to determine the maximum horizontal load to fracture the tooth, placing the tip 3 mm incisal to the cementoenamel junction. Mean values of the fracture strength were compared by ANOVA followed by a post hoc test. P < 0.05 was considered statistically significant. Results: No significant difference was observed among the MTA, BA, and biodentine experimental groups. Conclusion: All the three materials tested, may be used as effective strengthening agents for immature teeth.

scholarly journals Effect of whitening dentifrices on the surface roughness of a nanohybrid composite resin

2016 ◽  
Vol 10 (02) ◽  
pp. 170-175 ◽  
Author(s):  
Gabriela Migliorin da Rosa ◽  
Luciana Mendonça da Silva ◽  
Márcio de Menezes ◽  
Hugo Felipe do Vale ◽  
Diego Ferreira Regalado ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Composite Resin ◽  
Wilcoxon Test ◽  
Control Group ◽  
Mean Values ◽  
Short Period ◽  
Significant Difference ◽  
Before And After ◽  
Nanohybrid Composite ◽  
One Way Anova

ABSTRACT Objectives: The present study verified the influence of whitening dentifrices on the surface roughness of a nanohybrid composite resin. Materials and Methods: Thirty-two specimens were prepared with Filtek™ Z350 XT (3M/ESPE) and randomly divided into four groups (n = 08) that were subjected to brushing simulation equivalent to the period of 1 month. The groups assessed were a control group with distilled water (G1), Colgate Total 12 Professional Clean (G2), Sensodyne Extra Whitener Extra Fresh (G3), and Colgate Luminous White (G4). A sequence of 90 cycles was performed for all the samples. The initial roughness of each group was analyzed by the Surface Roughness Tester (TR 200-TIME Group Inc., CA, USA). After the brushing period, the final roughness was measured, and the results were statistically analyzed using nonparametric Kruskal–Wallis and Dunn tests for intergroup roughness comparison in the time factor. For intragroup and “Δ Final − Initial” comparisons, the Wilcoxon test and (one-way) ANOVA were, respectively, performed (α = 0.05). Results: The roughness mean values before and after brushing showed no statistically significant difference when the different dentifrices were used. None of the dentifrices analyzed increased significantly the nanohybrid composite resin surface roughness in a 1 month of tooth brushing simulation. Conclusions: These results suggest that no hazardous effect on the roughness of nanohybrid composite resin can be expected when whitening dentifrices are used for a short period. Similar studies should be conducted to analyze other esthetic composite materials.

scholarly journals Fracture Resistance of a Bulk-Fill and a Conventional Composite and a Combination of Both for Coronal Restoration of Severely Damaged Primary Anterior Teeth

2019 ◽  
Author(s):  
Shahram Mosharrafian ◽  
Maryam Shafizadeh ◽  
Zeinab Sharifi
Keyword(s):  
Fracture Resistance ◽  
Treatment Time ◽  
Testing Machine ◽  
Anterior Teeth ◽  
Significant Difference ◽  
Group 3 ◽  
The Mean ◽  
Group 2 ◽  
One Way Anova

Objectives: This study aimed to compare the fracture resistance of a bulk-fill and a conventional composite and a combination of both for coronal restoration of severely damaged primary anterior teeth. Materials and Methods: In this in vitro experimental study, 45 primary anterior teeth were randomly divided into three groups. After root canal preparation, the canals were filled with Metapex paste such that after the application of 1 mm of light-cure liner, 3 mm of the coronal third of the canal remained empty for composite post fabrication. Filtek Z250 conventional composite was used in group 1, Sonic-Fill bulk-fill composite was used in group 2 and Sonic-Fill with one layer of Filtek Z250 as the veneering were used in group 3. Adper Single Bond 2 was used in all groups. The teeth were thermocycled, and fracture resistance was measured by a universal testing machine. The mode of fracture was categorized as repairable or irreparable. Data were analyzed using one-way ANOVA. Results: The mean fracture resistance was 307.00±74.72, 323.31±84.28 and 333.30±63.96 N in groups 1 to 3, respectively (P=0.55). The mean fracture strength was 14.53±2.98, 15.08±2.82 and 15.26±3.02 MPa in groups 1 to 3, respectively (P=0.77). The frequency of repairable mode of failure was 80% for the conventional, 73.6% for the bulk-fill and 80% for the bulk-fill plus conventional group, with no significant difference (P>0.05). Conclusions: Bulk-fill composites can be used for coronal reconstruction of severely damaged primary anterior teeth similar to conventional composites to decrease the treatment time in pediatric patients.

scholarly journals Comparative analysis of the anterior and posterior length and deflection angle of the cranial base, in individuals with facial Pattern I, II and III

2013 ◽  
Vol 18 (1) ◽  
pp. 69-75 ◽  
Author(s):  
Guilherme Thiesen ◽  
Guilherme Pletsch ◽  
Michella Dinah Zastrow ◽  
Caio Vinicius Martins do Valle ◽  
Karyna Martins do Valle-Corotti ◽  
...  
Keyword(s):  
Deflection Angle ◽  
Cranial Base ◽  
Profile Angle ◽  
Mean Values ◽  
Anterior Cranial Base ◽  
Significant Difference ◽  
Facial Pattern ◽  
Caucasian Patients ◽  
The Mean ◽  
Post Hoc

OBJECTIVE: This study evaluated the variations in the anterior cranial base (S-N), posterior cranial base (S-Ba) and deflection of the cranial base (SNBa) among three different facial patterns (Pattern I, II and III). METHOD: A sample of 60 lateral cephalometric radiographs of Brazilian Caucasian patients, both genders, between 8 and 17 years of age was selected. The sample was divided into 3 groups (Pattern I, II and III) of 20 individuals each. The inclusion criteria for each group were the ANB angle, Wits appraisal and the facial profile angle (G'.Sn.Pg'). To compare the mean values obtained from (SNBa, S-N, S-Ba) each group measures, the ANOVA test and Scheffé's Post-Hoc test were applied. RESULTS AND CONCLUSIONS: There was no statistically significant difference for the deflection angle of the cranial base among the different facial patterns (Patterns I, II and III). There was no significant difference for the measures of the anterior and posterior cranial base between the facial Patterns I and II. The mean values for S-Ba were lower in facial Pattern III with statistically significant difference. The mean values of S-N in the facial Pattern III were also reduced, but without showing statistically significant difference. This trend of lower values in the cranial base measurements would explain the maxillary deficiency and/or mandibular prognathism features that characterize the facial Pattern III.

scholarly journals Safe Pedestrian Behaviours among Children Aged 7 to 9 in Malaysia

2019 ◽  
Vol 30 (2) ◽  
pp. 61-65
Author(s):  
Low Fin ◽  
Nurfatin Suhaimi ◽  
Nur Nor ◽  
Amelia Ghani
Keyword(s):  
Random Sample ◽  
Road Safety ◽  
Safety Education ◽  
The Road ◽  
Large N ◽  
Significant Difference ◽  
The Mean ◽  
Low Levels ◽  
Post Hoc ◽  
One Way Anova

The present study examined safe pedestrian behaviours according to the Malaysian Road Safety Education module among 7-year-old to 9-year-old children in Malaysia. A survey was conducted with a relatively large (n = 1206) random sample of children aged 7 to 9 years old, drawn from 24 selected schools in six states in Malaysia based on the highest numbers of crash cases. Analysis of one-way ANOVA revealed a statistically significant difference in safe pedestrian behaviours between different ages. Post hoc comparisons using the Tukey HSD test indicated that the mean score of safe pedestrian behaviours for 7-year-old children was significantly higher than that of 8-year-old children (p = .004) and 9-year-old children (p = .021). No statistically significant difference was revealed between the 8-year-olds and 9-year-olds (p = .859) at the 0.05 level. Although many children reported safe pedestrian behaviours, low levels of certain safe pedestrian behaviours were also reported – less than 30% of the children aged 7 to 9 reported to ‘always’ wear bright clothes, walk against the traffic, and wave at the drivers to cross the road. In addition, a small percentage (9.9-13.6%) of children aged 7 to 9 also reported to ‘always’ wear dark clothes at night, cross the street between parked cars, and run to cross the road. These findings may inform programs to improve children’s safe pedestrian behaviours.

scholarly journals Stakeholders’ impediments in promoting school nutrition education in South Africa: Implications on youth dietary knowledge of excess fats and carbohydrates

2021 ◽  
Vol 21` (01) ◽  
pp. 17158-17177
Author(s):  
Tafirenyika Mafugu ◽  
Keyword(s):  
South Africa ◽  
Nutrition Education ◽  
School Nutrition ◽  
Mean Values ◽  
Dietary Knowledge ◽  
Inadequate Knowledge ◽  
Significant Difference ◽  
The Mean ◽  
One Way Anova ◽  
Nutrition Programme

There is prevalence of overweight and obesity in South Africa. Evidence of nutrition knowledge and challenges affecting the promotion of nutrition interventions is needed to produce more effective strategies to prevent nutrition problems in schoolchildren. The study sought to explore challenges encountered by stakeholders of the school nutrition programme in promoting nutrition education. Furthermore, the study aimed to assess the implications of the stakeholders ‘challenges on learners’ dietary knowledge of excess fats and carbohydrates. The study took place in eight secondary schools in the Pinetown District, KwaZulu-Natal,South Africa. The qualitative data from nine interviewees who were stakeholders of the school nutrition programme were analysed using thematic content analysis. Quantitative data were collected from 108 grade 12learners using self-administered questionnaires.The quantitative data was coded, collated and analysed using SPSS. Independent sample t-test was used to evaluate if there was significant difference between gender and the mean values. One-way ANOVA was used to establish if there was any significant difference between the mean values of learners’ knowledge on various nutrition principles.Learners displayed inadequate knowledge of a healthy diet(34%),the importance of vegetables in the diet (71%), the health risks of excess fats (64.8%) and excess carbohydrates (77.8%),and nutritious food to be eaten daily (40.7%). Comparison of group means of various nutrition principles using one way ANOVA indicated significant difference at p < 0.05 level[F(4, 528) = 43.3, P < 0.001]. The 44 male respondents had significantly higher scores for the awareness of health risks of excess fats t (103) = 2.6, p =0.01and excess carbohydrates t (103) = 2.7, p =0.01 compared to 61 females.Each food group could be listed only by less than 22% of the participants. Challenges encountered in promoting nutrition education included time constraints, lack of training on nutrition principles, lack of supporting documents and lack of nutrition principles in the curriculum.The inadequate knowledge displayed by learners and lack of training and supporting documents in promoting nutrition education indicate areas that can be targeted by intervention programmes to improve nutrition knowledge of learners and stakeholders.

scholarly journals Pengaruh Perendaman Kopi Robusta dan Arabika terhadap Kekerasan Resin Komposit Nanofiller

e-GIGI ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Fransiska M. Pardosi ◽  
Darmawati A. Indraswari ◽  
Lusiana Batubara ◽  
Nadia Hardini
Keyword(s):  
Composite Resin ◽  
Artificial Saliva ◽  
Control Group ◽  
Arabica Coffee ◽  
Treatment Groups ◽  
Hardness Tester ◽  
Robusta Coffee ◽  
Significant Difference ◽  
Post Hoc ◽  
One Way Anova

Abstract: Nanofiller composite resin has small filler size which enhances its properties. However, these properties could decrease due to several factors. Acidic liquid such as coffee could reduce the hardness of composite resin. This study was aimed to analyze the effect of robusta and arabica coffee immersion on the hardness of nanofiller composite resin. A total of 27 composite resin samples were used and then were polished by using a soflex disc for 30 seconds on each roughness level. Samples were then divided into three groups, as follows: the control group with artificial saliva and the treatment groups with robusta coffee and arabica coffee. The composite resin molds were immersed in the three groups for 5 days. After five days of immersion, the hardness of the sample was tested by using a Vickers hardness tester. Artificial saliva as the control group had the highest mean hardness value of 112.98±8.67 VHN, followed by robusta coffee, and then by arabica coffee. The One Way Anova and post hoc LSD test showed that there were significant differences in all groups (p<0.05) except for the two treatment groups, namely robusta and arabica coffee groups which did not show any significant difference in the resin hardness (p>0.05). In conclusion, robusta and arabica coffee affect the hardness of the nanofiller composite resin, but there is no significant difference in the hardness between the robusta and arabica coffee groups.Keywords: composite resin hardness, nanofiller, robusta coffee, arabica coffee Abstrak: Resin komposit nanofiller memiliki ukuran filler kecil yang dapat meningkatkan fungsinya namun fungsi tersebut dapat menurun oleh beberapa hal. Cairan asam yang dikonsumsi seperti kopi dapat menurunkan kekerasan resin komposit. Penelitian ini bertujuan untuk mengetahui pengaruh perendaman kopi robusta dan arabika terhadap kekerasan resin komposit nanofiller. Sampel resin komposit yang digunakan sebanyak 27 buah dan dilanjutkan dengan pemolesan menggunakan soflex disc selama 30 detik setiap tingkat kekasarannya. Sampel kemudian dibagi dalam tiga kelompok, yaitu kelompok kontrol dengan saliva buatan dan dua kelompok perlakuan dengan kopi robusta dan arabika. Sebanyak 27 buah resin komposit direndam ke dalam tiga kelompok tersebut selama lima hari kemudian diuji kekerasannya dengan vickers hardness tester. Saliva buatan sebagai kelompok kontrol memiliki nilai rerata kekerasan tertinggi sebesar 112,98±8,67 VHN, diikuti kopi robusta, dan nilai terendah yaitu kopi arabika. Hasil uji One Way Anova dan post hoc LSD menunjukkan terdapat perbedaan bermakna pada semua kelompok (p<0,05) kecuali pada kedua kelompok perlakuan yaitu antara kopi robusta dan arabika tidak menunjukkan adanya perbedaan kekerasan yang bermakna (p>0,05). Simpulan penelitian ini ialah kopi robusta dan arabika memengaruhi kekerasan resin komposit nanofiller namun tidak terdapat perbedaan kekerasan antara keduanya.Kata kunci: kekerasan resin komposit, nanofiller, kopi robusta, kopi arabika

scholarly journals Fracture Resistance of Ceramic Laminate Veneers Bonded to Teeth with Class V Composite Fillings after Cyclic Loading

2018 ◽  
Vol 2018 ◽  
pp. 1-6
Author(s):  
Leyla Sadighpour ◽  
Farideh Geramipanah ◽  
Vanya Rasaei ◽  
Mohammad J. Kharazi Fard
Keyword(s):  
Cyclic Loading ◽  
Fracture Resistance ◽  
Resin Cement ◽  
Crown Height ◽  
Class V ◽  
Significant Difference ◽  
Failure Loads ◽  
The Mean ◽  
Laminate Veneers ◽  
One Way Anova

Purpose. Porcelain laminate veneers (PLVs) are sometimes required to be used for teeth with composite fillings. This study examined the fracture strength of PLVs bonded to the teeth restored with different sizes of class V composite fillings. Materials and Methods. Thirty-six maxillary central incisors were divided into three groups (n=12): intact teeth (control) and teeth with class V composite fillings of one-third or two-thirds of the crown height (small or large group, resp.). PLVs were made by using IPS e.max and bonded with a resin cement (RelyX Unicem). Fracture resistance (N) was measured after cyclic loading (1 × 106 cycles, 1.2 Hz). For statistical analyses, one-way ANOVA and Tukey test were used (α=0.05). Results. There was a significant difference between the mean failure loads of the test groups (P=0.004), with the Tukey-HSD test showing lower failure loads in the large-composite group compared to the control (P=0.02) or small group (P=0.05). The control and small-composite groups achieved comparable results (P>0.05). Conclusions. Failure loads of PLVs bonded to intact teeth and to teeth with small class V composite fillings were not significantly different. However, extensive composite fillings could compromise the bonding of PLVs.

scholarly journals Resistant Starch Content of Traditional Indian Legume Preparations

2017 ◽  
Vol 5 (3) ◽  
pp. 238-246 ◽  
Author(s):  
Madhuri Nigudkar ◽  
Jagmeet Gurminder
Keyword(s):  
Chronic Diseases ◽  
Resistant Starch ◽  
Starch Content ◽  
Bengal Gram ◽  
Significant Difference ◽  
The Mean ◽  
Cooked Food ◽  
Level Of Significance ◽  
Post Hoc ◽  
One Way Anova

Foods rich in resistant starch RS can play an important role in the management of chronic diseases. Legumes contain higher amount of RS than cereals, roots and tubers. Therefore the current study was undertaken to estimate RS content of some commonly consumed Indian legume preparations. 26 cooked legume based products including 6 readymade traditional snacks were tested for their RS content using Megazyme Assay Kit for Resistant Starch. RS content was estimated for 100 g cooked food and for the cooked portion obtained by using 30 g of major ingredient. One way ANOVA with post hoc Tukey’s test was used to compare the mean RS content in one portion of different categories of legume preparations. Level of significance was set at p<0.05. RS content of four types of plain pressure cooked dhal, common to Indian cooking, was in the range of 1.21 g% to 2.16 g% whereas aamti, a thinner preparation of dhal contained RS in the range of 0.42 g% to 0.69 g%. In both types of dhal preparations, red gram dhal showed highest RS content followed by bengal gram dhal. Usal made using bengal gram kabuli contained 2.38 g% RS followed by 1.42 g% RS in bengal gram brown usal. RS in bengal gram flour based traditional recipes like zunka, dhirda and pithle was 1.23 g%, 1.48 g% and 0.09 g% respectively. When mean RS content of one portion of different categories of legume preparations was compared, there was no significant difference p≥0.05 found among any of the categories. The results of the study generated useful data with respect to RS content in 100 g as well as RS in one portion of legume preparations and identified preparations with red gram dhal, bengal gram kabuli and brown variety and lentil as relatively higher in RS content.

scholarly journals Analysis of Ecology of a Little Known White Oak Quercus Polycarpa Schur, Using Geobiocoenological Typology

2009 ◽  
Vol 2 (2) ◽  
pp. 30-40
Author(s):  
Radim Matula
Keyword(s):  
Quercus Petraea ◽  
White Oak ◽  
Trophic Conditions ◽  
The Czech Republic ◽  
Mean Values ◽  
Crown Diameter ◽  
Altitudinal Zone ◽  
The Mean ◽  
Post Hoc ◽  
One Way Anova

Analysis of Ecology of a Little Known White Oak Quercus Polycarpa Schur, Using Geobiocoenological Typology Quercus polycarpa Schur is a little known oak species of the Sessile Oak aggregate (Quercus petraea s. lat.). Different habitats were studied using geobiocoenological typology system in order to investigate its ecology. In total, 65 experimental plots were set in forest stands with Q. polycarpa in the main storey in 12 protected areas situated in south-east of the Czech Republic. Ecological conditions, basic tree parameters and representation of Q. polycarpa within other oak species were evaluated on each plot. The mean values of height, height of life crown setting, stem and crown diameter were related to sub-categories of geobiocoenological system and compared by one-way ANOVA and Scheffé post-hoc test. It has been found out that Q. polycarpa grow in a high number in the 2nd altitudinal zone. It often occurs in a variety of habitats with different hydric and trophic conditions. As expected, the lowest values of measured parameters were found in the dry hydric range, this species reaches the highest values in the normal hydric and mesic ranges.

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