scholarly journals Evaluation of Fracture Resistance of Orthodontic Mini-implants in the Transmucosal Profile Region

2015 ◽  
Vol 16 (5) ◽  
pp. 372-375 ◽  
Author(s):  
Adelson Mota de Aguiar ◽  
Arilton Mota de Aguiar ◽  
Célia Regina Maio Pinzan-Vercelino ◽  
Fausto Silva Bramante
Keyword(s):  
Fracture Resistance ◽  
Testing Machine ◽  
Significance Level ◽  
Group Iii ◽  
Mini Implants ◽  
Group I ◽  
Significant Difference ◽  
The Mean ◽  
Group Ii

ABSTRACT Aim This study sought to compare the fracture resistance of three trademarked orthodontic mini-implants in the transmucosal profile region. Thirty-six mini-implants of three different brands, separated into groups I, II and III, were tested. Each group consisted of 12 mini-implants of 6 mm in length. The mean diameter and length of the transmucosal profile of the mini-implants were 1.90 and 2.0 mm in group I, 1.77 and 1.0 mm in group II and 1.50 and 1.0 mm in group III, respectively. The tests were performed on a universal testing machine in compression mode, with a 2,000 kgf load, a speed of 4.0 mm per minute and a chisel-shaped active tip, which acted crosssectionally on the transmucosal profile. Single-criterion analysis of variance was used to compare the three brands. A significance level of 5% and test power of 80% were adopted. The mean fracture resistance achieved by the mini-implants was 172.03 ± 25.59 N for group I, 162.35 ± 30.81 N for group II and 139.69 ± 42.99 N for group III. There was no statistically significant difference in mean fracture resistance among the tested mini-implant brands. Conclusion The transmucosal profile diameter does not seem to be a deciding factor in the choice of mini-implants to minimize the risk of fractures. Clinical significance Although being an in vitro study it is possible to believe that this new brand has a very satisfactory resistance to fracture and enables its use with great efficiency. How to cite this article de Aguiar AM, Bramante FS, de Aguiar AM, Pinzan-Vercelino CRM. Evaluation of Fracture Resistance of Orthodontic Mini-implants in the Transmucosal Profile Region. J Contemp Dent Pract 2015;16(5):372-375.

scholarly journals Effect of Hand and Rotary Instruments on the Fracture Resistance of Teeth: An In Vitro Study

2020 ◽  
Vol 8 (2) ◽  
pp. 38
Author(s):  
Nisha Acharya ◽  
Md Riasat Hasan ◽  
Dashrath Kafle ◽  
Anil Chakradhar ◽  
Takashi Saito
Keyword(s):  
Fracture Resistance ◽  
Testing Machine ◽  
Compressive Load ◽  
In Vitro Study ◽  
Group Iv ◽  
Group Iii ◽  
Group I ◽  
Significant Difference ◽  
Group Ii

Objective: Endodontic treatment should be both conservative and effective. Endodontic instruments with a greater taper are used for coronal flaring, for proper debridement with efficient irrigation. However, increased taper of an instrument can remove a larger amount of pericervical dentin, compromising the strength of the tooth. The aim of this study was to determine the effect of hand files, ProTaper Universal, ProTaper Next, and V Taper rotary instrument systems on the fracture resistance of teeth. Materials and Methods: In total, 60 extracted human maxillary first premolars were divided into four groups—Group I (Hand Files; HF), Group II (ProTaper Universal; PT), group III (ProTaper Next; PTN) and Group IV (V Taper; VT) (N = 15). Each group was instrumented with the respective instrument system, irrigated, obturated, restored, and mounted in cold cure acrylic. A universal load-testing machine (Shimadzu, Japan) was used to apply a vertical compressive load. The maximum force was recorded in Newton. Analysis of variance (ANOVA) and Independent t-tests were applied to compare the maximum mean force required to fracture the tooth. Results: There was a statistically significant difference in fracture resistance between Group I (HF) and Group II (PT) and between Group II (PT) and Group IV (VT) (p < 0.001). Similarly, a significant difference was observed between Group II (PT) and Group III (PTN) (p < 0.01). Furthermore, a significant difference was observed between Group I (HF) and Group III (PTN), and between Group III (PTN) and Group IV (VT) (p < 0.05), too. However, there was no statistically significant difference between Group I (HF) and group IV (VT) (p > 0.05). Conclusion: Rotary files with more taper seem to remove more pericervical dentin than traditional manual and rotary files with less taper, thus altering the strength of the tooth.

scholarly journals Fracture Resistance of Primary Canines Restorations Reinforced with a Flowable or a Packable Composite Resin Posts; In- Vitro

2021 ◽  
Author(s):  
Ghasem Ansari ◽  
Fatemeh javadi ◽  
Kiana Hanjani ◽  
Ahmad Najafi Abrandabadi ◽  
Mahshid Gashtasb ◽  
...  
Keyword(s):  
Fracture Resistance ◽  
Composite Resin ◽  
Testing Machine ◽  
P Value ◽  
Anterior Teeth ◽  
Group I ◽  
Significant Difference ◽  
The Mean ◽  
Group Ii ◽  
Type Of Fracture

Abstract Aim and Background: Restoration of severely damaged primary anterior teeth are deemed as serious challenges for pediatric dentists. The aim of this study was to evaluate the fracture resistance of primary canines restored with flowable or packable composite resin posts. Material and Methods This study was conducted on a group of extracted primary canines. After cutting the coronal section, standard pulpectomy was performed and root canals were filled with ZOE paste leaving 3 mm coronal root space. A liner was placed above the root canal filling as a barrier. Samples were then randomly divided into two groups of fifteen. Both groups, received etch, bond, then in group I Core Flo Composite resin placement into canal, in group II, post shaping using designated packable composite resin and inserted into the canal. Followed by Core buildup and Crown reconstruction using Z250 composite resin. Samples were mounted at 148 ° angle on the acrylic blocks and stored in de-ionized water for 72 hours. Fracture resistance was measured using Universal Testing Machine. Data analysis were performed using independent t-test. Chi- square test were also employed to assess the type of fracture within groups. Results The mean fracture resistance in the group I was 830.31(+/-328.69N) and 803.09(+/-326.45N) in group II. Moreover, statistical analyses of the results showed no significant difference between the mean values of the fracture resistance (p-value=0.822) of groups as well as the type of fracture (p-value=0.79) between groups. Conclusion The ease of use and proper adhesion of the Core Flo composite resin, seems to help its use in the reconstruction of severely destructed anterior primary teeth.

scholarly journals Comparison of Enamel Preparations - Bevel, Chamfer and Stair Step Chamfer on Fracture Resistance of Nano Filled Resin Composites Using Bulk Pack Technique - An In Vitro Study

2019 ◽  
Vol 7 (23) ◽  
pp. 4089-4093
Author(s):  
Jyothi Bommanagoudar ◽  
Shashidhar Chandrashekhar ◽  
Shilpa Sharma ◽  
Hiten Jain
Keyword(s):  
Fracture Resistance ◽  
Failure Load ◽  
Testing Machine ◽  
In Vitro Study ◽  
Control Group ◽  
Tooth Structure ◽  
Group I ◽  
Significant Difference ◽  
The Mean

AIM: To evaluate and compare the effect of enamel preparation designs bevel, chamfer and stair-step chamfer on the fracture resistance of nanocomposite. METHODS: The sample group of this study consisted of 72 non-carious permanent maxillary central incisors. The sample is divided into four groups of 18 each. Group, I control Group II bevel preparation, Group III chamfer preparation, group IV stair step chamfer preparation. After the specific preparation, each tooth is filled with nanocomposite using bulk pack technique. The teeth were subjected to fracture resistance test under Universal testing machine and then were examined under a stereomicroscope to evaluate the type of bond failure. The results were subjected to statistical analysis. RESULTS: Results of the One-Way ANOVA revealed a significant difference in the mean peak failure load values of the four different groups. (P < 0.001) Tukey’s Post-Hoc comparison test revealed that there was a significant difference in the mean peak failure load values of the bevel and chamfer preparation. But there was no significant difference between chamfer and stair-step chamfer preparation designs. CONCLUSION: Stair-step chamfer preparation demonstrated comparable values to Chamfer preparation but also involved the removal of less amount of tooth structure adjacent to the fractured edge and good esthetic technique.

scholarly journals Comparative Evaluation of Fracture Resistance of Endodontically Treated Teeth Restored with Resin Fiber Post and Stainless Steel Post: An In Vitro Study

2015 ◽  
Vol 03 (02) ◽  
pp. 080-084
Author(s):  
Vijay Singh ◽  
Poonam Bogra ◽  
Saurabh Gupta ◽  
Navneet Kukreja ◽  
Neha Gupta
Keyword(s):  
Stainless Steel ◽  
Fracture Resistance ◽  
Testing Machine ◽  
Compressive Force ◽  
Control Group ◽  
Fiber Post ◽  
Endodontically Treated Teeth ◽  
Group I ◽  
Significant Difference

AbstractFracture resistance of endodontically treated teeth restored with post. Aims: This study aims to compare the fracture resistance of endodontically treated teeth restored with resin fiber and stainless steel post. Commercially available prefabricated resin fiber post(Dentsply Maillefer Easy Post), prefabricated stainless steel post(Coltene/Whaledent Parapost) were used. Methods and Material: Forty five maxillary central incisors were obturated and divided into 3 groups: Control Group (Group I) without any post (n = 15), Resin Fiber Post Group (Group II) (n = 15) and Stainless Steel Post Group (Group III) (n = 15). In all Groups except control group, post space was prepared; a post was cemented, and a core build-up was provided. All the specimens were subjected to compressive force under a universal testing machine until fracture. Statistical analysis used: The results were analyzed using the variable analysis test (ANOVA). Results: One-way analysis of variance revealed significant difference among test groups. The control group demonstrated highest fracture resistance (925.2183 N), followed by the resin fiber post group (486.7265 N) and stainless steel post group (423.539N). Conclusions: Teeth restored with resin fiber post showed higher fracture resistance values than prefabricated stainless steel post.

The Role of sFas in the Immune Escape Mechanism and Progression of Cancer Larynx

2009 ◽  
Vol 2 ◽  
pp. CMENT.S2565
Author(s):  
Amr A El Badry ◽  
Ismail Elmofty ◽  
Amira Helmy
Keyword(s):  
Serum Level ◽  
Buffy Coat ◽  
Control Group ◽  
Group Iii ◽  
Soluble Fas ◽  
Group I ◽  
Significant Difference ◽  
Cancer Larynx ◽  
The Mean ◽  
Group Ii

This work assess serum levels of soluble Fas form (sFas) in patients with different stages of laryngeal squamous cell carcinoma(LSCC) to investigate its prognostic significance. We correlate its levels with the morphological changes of peripheral blood cells via buffy coat examinatin. The study population included 70 patients clinically diagnosed and pathohistologically confirmed LSCC in addition to 20 healthy controls. According to TNM classification 33(47.1%) patients were in stage I (group I) and 24(34.3%) in stage II (group II), 13(18.5%) in stage III (group III). The results revealed that the mean serum level of sFas (pg/ml) in the control group was 51.2, in group I was 66.33, in group II was 81.33 and in group III was 112.45. Statistical analysis of the mean of sFas by ELISA test in the patients' groups in comparison to the control revealed a significant increase of both group II and III in comparison to the control group (P < 0.01) but there was no significant difference (P > 0.05) between group I in comparison to either the control or group II. There was a significant difference (P < 0.05) between group I in comparison to group III. LM examination revealed massive extent of the apoptotic cells in group III when compared to both group I and group II. EM examination of the buffy coat revealed apoptotic changes, mainly in the peripheral blood mononuclear cells (PBMNCs), represented by surface membrane ruffles and blebs with clumped nuclear chromatin and vacuolated cytoplasm. In conclusion, this study may help us to better understand one of the escape mechanisms in cancer larynx. This mechanism is represented by the significant increase in both the serum level of sFas and the morphological apoptotic changes that detected in PBMNCs. Soluble Fas may contribute to the progression of laryngeal cancer. It can be used as an attractive target for anticancer therapy and may be considered as a marker of disease progression and poor prognosis in laryngeal cancer.

scholarly journals Effects of different bleaching methods on shear bond strengths of orthodontic brackets

2012 ◽  
Vol 83 (4) ◽  
pp. 686-690 ◽  
Author(s):  
Ahmet Yalcin Gungor ◽  
Erhan Ozcan ◽  
Huseyin Alkis ◽  
Hakan Turkkahraman
Keyword(s):  
Shear Bond Strength ◽  
Testing Machine ◽  
Orthodontic Brackets ◽  
Group Iii ◽  
Group I ◽  
Human Enamel ◽  
Significant Difference ◽  
Bond Strengths ◽  
Group Ii ◽  
Method Group

ABSTRACT Objective: To evaluate the effects of different bleaching methods on the shear bond strength (SBS) of orthodontic brackets. Materials and Methods: Forty-five freshly extracted premolars were randomly divided into three groups (n  =  15 per group). In group I, bleaching was performed with the office bleaching method. In group II, bleaching was performed with the home bleaching method. Group III served as the control. Orthodontic brackets were bonded with a light cure composite resin and cured with an LED light. After bonding, the SBS of the brackets were tested with a Universal testing machine. Results: Analysis of variance indicated a significant difference between groups (P &lt; .001). The highest values for SBS were measured in group III (20.99 ± 2.32 MPa). The SBS was significantly lower in groups I and II than in group III (P &lt; .001). The lowest values for SBS were measured in group II (6.42 ± 0.81 MPa). SBS was significantly higher in group I than in group II (P &lt; .001). Conclusions: Both of the bleaching methods significantly affected the SBS of orthodontic brackets on human enamel. Bleaching with the home bleaching method affected SBS more adversely than did bleaching with the office bleaching method.

scholarly journals An in vitro comparative Evaluation of Fracture Strength of Roots Instrumentated with Self-adjusting File and Reciproc Reciprocating File, with and without Obturation

2017 ◽  
Vol 1 (1) ◽  
pp. 20-25
Author(s):  
Pooja Kabra
Keyword(s):  
Fracture Strength ◽  
Comparative Evaluation ◽  
Group Iv ◽  
Control Group ◽  
Group V ◽  
Group Iii ◽  
Group I ◽  
Significant Difference ◽  
Group Ii

ABSTRACT Aim The purpose of this study was to evaluate the fracture strength of roots instrumented with the self-adjusting file (SAF; ReDent-Nova, Ra'anana, Israel) and the Reciproc reciprocating file and that were and were not obturated using the warm vertical lateral compaction technique. Materials and methods In total, 75 mandibular premolar teeth were sectioned at or below the cementoenamel junction to obtain roots 13 mm in length. The roots were balanced with respect to buccolingual and mesiodistal diameters and weight. They were distributed into four experimental groups and one control group (n = 15): No instrumentation (group I), instrumentation with SAF files but no obturation (group II), instrumentation with SAF files and obturated with warm vertical lateral compaction (group III), instrumentation with Reciproc File but no obturation (group IV), and instrumentation with Reciproc File and obturated with warm vertical lateral compaction (group V). AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) was used along with gutta-percha points. One week later, a vertical load was applied to the specimen's canal until fracture occurred. Data were statistically analyzed using one-way analysis of variance (p = 0.05). Results The mean fracture load was 312.83 N for group I, 297.35 N for group II, 359.15 N for group III, 231.51 N for group IV, and 275.81 N for group V. Conclusion The fracture resistances exhibited a statistically significant difference between all the groups. Teeth instrumented by SAF exhibited a better fracture resistance. How to cite this article Tyagi S, Choudhary E, Kabra P, Chauhan R. An in vitro comparative Evaluation of Fracture Strength of Roots Instrumentated with Self-adjusting File and Reciproc Reciprocating File, with and without Obturation. Int J Clin Dent Res 2017;1(1):20-25.

scholarly journals Transverse Strength of Heat Cured Acrylic Resin After Immersed in 0, 2% Chlorhexidine Gluconate Mouthwash (In Vitro)

2017 ◽  
Vol 1 ◽  
Author(s):  
Annisa Mayang Rusdi ◽  
Lasminda Syafiar ◽  
Astrid Yudhit
Keyword(s):  
Testing Machine ◽  
Acrylic Resin ◽  
Chlorhexidine Gluconate ◽  
P Value ◽  
Group V ◽  
Group Iii ◽  
Transverse Strength ◽  
Group I ◽  
Significant Difference

<p class="AbstractContent"><strong>Objective:</strong> The purpose of this study was to evaluate transverse strength of heat cured acrylic resin after immersed in 0,2% chlorhexidine gluconate mouthwash for 15, 30, 45, and 60 minutes.</p><p class="AbstractContent"><strong>Methods:</strong> This was an experimental laboratory study with posttest only group design. The samples were heat cured acrylic resin plate with size 65mm x 10mm x 2,5mm. Polymerization of the heat cured acrylic was done by water bath (74 °C for 2hrs followed by 100 °C for 1hr). Totally 30 samples were prepared and divided into 5 groups (n=6) which are group I as control, and others were immersed in 0, 2% chlorhexidine gluconate, group II (15 minutes), group III (30 minutes), group IV (45 minutes) and group V (60 minutes) respectively. The transverse strength was test using Torsee’s Universal Testing machine, Japan with crosshead 1/10 mm/seconds. The data was statistically analyzed using one way ANOVA (p≤0,005).</p><p class="AbstractContent"><strong>Results:</strong> Means and Standard deviation of Transverse strength were 92.382±11.786 N/mm2, 92.186±13.349 N/mm2,92.578±12.492 N/mm2, 92.382±13.939 N/mm2, and 91.989±12.285 N/mm2 for group I, II, III, IV, and V respectively. Statistic analyzed showed no significant difference among groups with p value= 1,000 (p &lt; 0, 05).</p><p class="AbstractContent"><strong>Conclusion:</strong> The immersion in 0, 2% chlorhexidine gluconate mouthwash at different period does not changed transverse strength of heat cured acrylic resin.</p>

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 Microshear bond strength evaluation of surface pretreated zirconia ceramics bonded to dentin

2015 ◽  
Vol 09 (02) ◽  
pp. 224-227 ◽  
Author(s):  
Shenbagakuttalam Anand ◽  
Ambrose Vedamanickam Rajesh Ebenezar ◽  
Nirupa Anand ◽  
Kothandaraman Rajkumar ◽  
Sekar Mahalaxmi ◽  
...  
Keyword(s):  
Bond Strength ◽  
Testing Machine ◽  
Group Iv ◽  
Zirconia Ceramics ◽  
Group V ◽  
Statistical Significant Difference ◽  
Group Iii ◽  
Group I ◽  
Significant Difference ◽  
Group Ii

ABSTRACT Objectives: To comparatively assess the micro shear bond strength (MSBS) of dentin bonded surface pre-treated zirconia ceramics. Materials and Methods: Zirconia blocks were sectioned into 50 cubical blocks. The blocks were further categorized into five groups (n = 10 each). Group I: No treatment was performed on zirconia samples; Group II: The zirconia samples were sand-blasted; Group III: Group II + etched with 9.8% of hydrofluoric (HF) acid for 60 s; Group IV: The sandblasted zirconia samples were selectively infiltrated with low fusing porcelain; and Group V: Group IV + etched using 9.8% HF acid gel. The zirconia specimens were then bonded to dentin samples, and the samples were tested for MSBS evaluation using universal testing machine. Results: The MSBS of all the four experimental groups shows greater value than group I. Among the experimental groups, group V and group IV do not show any statistical significant difference, whereas the mean MSBS of groups IV and V were statistically greater than group III and group II. However, groups I, II, and III do not show any statistical significant difference in mean MSBS values between them. Conclusion: Selective infiltration etching of zirconia ceramics provides the highest bond strength with resin cement.

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