scholarly journals Influence of Orthodontic Anchor Screw Anchorage Method on the Stability of Artificial Bone: An In Vitro Study

Materials ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3205 ◽  
Author(s):  
Seen-Young Kang ◽  
Ji-Min Yu ◽  
Hyoung-Sik Kim ◽  
Jun-Seok Lee ◽  
Chan-Mi Yeon ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Automatic Device ◽  
Insertion Torque ◽  
Artificial Bone ◽  
Artificial Bones ◽  
Significant Difference ◽  
The Mean ◽  
The Stability ◽  
Torque Values

This study aims to compare the torque values for various lengths of the titanium-based orthodontic anchor screw (OAS), different anchorage methods and varying artificial bone densities after predrilling. Furthermore, the effects of these parameters on bone stability are evaluated. A total of 144 OASs were prepared with a diameter of 1.6 mm and heights of 6, 8 and 10 mm. Artificial bones were selected according to their density, corresponding to Grades 50, 40 and 30. Torque values for the automatic device and manual anchorage methods exhibited a statistically significant difference for the same-sized OAS, according to the bone density of the artificial bones (p < 0.05). However, when insertion torque was at the maximum rotations, there was no significant difference in the torque values for the Grade 30 artificial bone (p > 0.05). When the torque values of both anchorage methods were statistically compared with the mean difference for each group, the results of the manual anchorage method were significantly higher than those of the automatic device anchorage method (p < 0.05). A statistically significant difference was observed in the bone stability resulting from different OAS anchorage methods and artificial bone lengths. These findings suggest that the automatic anchorage method should be used when fixing the OAS.

scholarly journals Drilling Capability of Orthodontic Miniscrews: In Vitro Study

2020 ◽  
Vol 8 (4) ◽  
pp. 138
Author(s):  
Alessandra Marchi ◽  
Matteo Camporesi ◽  
Maurizio Festa ◽  
Luis Salvatierra ◽  
Sara Izadi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bone Density ◽  
Structural Changes ◽  
In Vitro Study ◽  
The Self ◽  
Bone Block ◽  
Insertion Torque ◽  
Artificial Bone ◽  
Torque Values

The aims of this study were to assess the values and mechanical properties of insertion torque (IT) of steel miniscrews inserted in artificial bone blocks (Sawbones, Pacific Research Laboratories, Vashon, WA, USA) with different bone densities and to detect any scratches on the surface of the miniscrews after insertion. Forty self-drilling miniscrews (Leone S.p.A. ø 1.75 mm, L 8 mm) have been inserted into bone blocks that mimic different stability conditions (density: 20 PCF—pounds per cubic foot, 40 PCF, and 30 + 50 PCF with 2 mm and 4 mm of cortical bone). Before insertion and after removal, all miniscrews were inspected with a stereomicroscope 5x and a SEM to detect potential microscopic cracks. Using an electronic surgical motor (W&H Dentalwerk Bürmoos GmbH, Werner Bader Str. 1, 5111 Bürmoos, Austria), the maximum insertion torque value was registered. Stereomicroscope and SEM examination did not indicate any morphological and surface structural changes to the miniscrews, irrespective of the bone density they were inserted into. The findings showed that IT increased significantly with increasing bone density. In each artificial bone block, morphostructural analysis demonstrated the adequate mechanical properties of the self-drilling miniscrews. IT measurements indicated torque values between 6 and 10 Ncm for blocks with a density of 30 + 50 PCF, whereas the suggested values are between 5 and 10 Ncm.

Reverse torque values of abutment screws after dynamic loading: The effects of sealant agents and the taper of conical connections

2020 ◽  
Author(s):  
Arda Ozdiler ◽  
suleyman dayan ◽  
Burc Gencel ◽  
Gulbahar Isık-Ozkol
Keyword(s):  
Dynamic Loading ◽  
Antibacterial Agent ◽  
In Vitro Study ◽  
Control Group ◽  
Silicone Sealant ◽  
Reverse Torque ◽  
The Stability ◽  
Torque Values ◽  
Chlorhexidine Gel

This in vitro study evaluated the influence of taper angles on the internal conical connections of implant systems and of the application of chlorhexidine gel as an antibacterial agent or a polyvinyl siloxane (PVS) sealant on the reverse torque values of abutment screws after dynamic loading. The current study tested four implant systems with different taper angles (5.4°, 12°, 45°, and 60°). Specimens were divided into three groups: control (neither chlorhexidine gel filled nor silicone sealed), 2% chlorhexidine gel-filled or silicone-sealed group, and group subjected to a dynamic load of 50 N at 1 Hz for 500,000 cycles prior to reverse torque measurements. Quantitative positive correlation was observed between the taper angle degree and the percentage of tightening torque loss. However, this correlation was significant only for the 60° connection groups except in the group in which a sealant was applied ( p = 0.013 for the control group, p = 0.007 for the chlorhexidine group). Percentages of decrease in the torque values of the specimens with silicone sealant application were significantly higher compared with both the control and chlorhexidine groups ( p = 0.001, p = 0.002, p = 0.001, and p = 0.002, respectively, according to the increasing taper angles); the percentage of decrease in torque values due to chlorhexidine application was statistically insignificant when compared with the control group. The application of gel-form chlorhexidine as an antibacterial agent does not significantly affect the stability of the implant–abutment connection under dynamic loads. PVS sealants may cause screw loosening under functional loads.

Effect of Different Intermediary Bases on Microleakage of a Restorative Material in Class II Box Cavities of Primary Teeth

2017 ◽  
Vol 40 (2) ◽  
pp. 82-87 ◽  
Author(s):  
Faika Y. Abdelmegid ◽  
Fouad S. Salama ◽  
Waleed M. Al-Mutairi ◽  
Saud K. Al-Mutairi ◽  
Sultan O. Baghazal
Keyword(s):  
Primary Teeth ◽  
In Vitro Study ◽  
Class Ii ◽  
Positive Control ◽  
Negative Control ◽  
The Other ◽  
Control Groups ◽  
Significant Difference ◽  
The Mean

Introduction The aim of this in vitro study was to assess and compare the effect of different intermediary bases on microleakage between tooth and a nanocomposite interface in Class II box cavities in primary teeth. Methods Standard Class II box cavities were prepared in 52 primary molars and randomly divided into 9 groups according to the intermediary base used (Multicore Flow, Fuji II LC, SDR, Smart Dentin Replacement, and Biodentine). All specimens were subjected to thermocycling and prepared for microleakage testing and evaluation. Results There was significant difference in the mean ranks of microleakage between the 9 groups, which was observed in the gingival side (p<0.0001) and the occlusal side (p<0.0001). The mean ranks microleakage was significantly higher with experimental SDR, experimental Multicore Flow, and positive control materials when compared with the other 6 groups. The microleakage mean ranks were statistically significantly lower in experimental Fuji II LC, experimental Biodentine, and all negative control groups when compared with the other 3 groups. Conclusions Microleakage is affected by the application of intermediate material. Experimental Biodentine and Fuji II LC showed the lowest microleakage while experimental SDR and experimental Multicore Flow showed the highest microleakage.

scholarly journals Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization – An in vitro Study

2016 ◽  
Vol 17 (4) ◽  
pp. 300-305 ◽  
Author(s):  
JM Gross ◽  
GG Nascimento ◽  
VC Araújo ◽  
MJS Bönecker ◽  
C Furuse
Keyword(s):  
Surface Analysis ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Cleaning Process ◽  
Artificial Bone ◽  
Orthodontic Anchorage ◽  
Synthetic Bone ◽  
Mini Implants ◽  
The Mean

ABSTRACT Objective This study aimed to investigate, in vitro, possible alterations on mini-implants surface after retrieval and if the cleaning process and sterilization can predispose damages. Materials and methods Two commercial mini-implants were tested for deformations after drilling and removing in artificial bone four times. Samples were analyzed by scanning electron microscopy, and surface alterations verified through thread and pitches deformation. To alterations caused by insertion/removal and the cleaning process and sterilization were verified in different procedures: Insertions and sterilization, only insertions, and only sterilization. Photomicrographs were analyzed in order to compare the surface characteristics. Head deformation was verified qualitatively. For a quantitative analysis, distances between threads were measured across the active part of the mini-implants. Results No deformation was observed in both groups. The cleaning and sterilization processes did not provoke alteration in both groups. Nevertheless, the presence of synthetic bone was noted in some samples. The mean distances between implant threads were similar after all steps in all regions in both groups. Conclusion The results suggest that the tested mini-implants can be retrieved without damage of its surface after four cycles of insertion, removal, and sterilization. Clinical significance Mini-implants can be retrieved without damage to its surface after four cycles of insertion, removal, and sterilization in the same patient without representing a biological concern. How to cite this article Gross JM, Nascimento GG, Araújo VC, Bönecker MJS, Furuse C. Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization – An in vitro Study. J Contemp Dent Pract 2016;17(4):300-305.

scholarly journals Torque Loss After Miniscrew Placement: An In-Vitro Study Followed by a Clinical Trial

2016 ◽  
Vol 10 (1) ◽  
pp. 251-260 ◽  
Author(s):  
Marco Migliorati ◽  
Sara Drago ◽  
Fabrizio Barberis ◽  
Irene Schiavetti ◽  
Domenico Dalessandri ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Insertion Time ◽  
Controlled Environment ◽  
Insertion Torque ◽  
Experimental Setup ◽  
Percentage Difference ◽  
Torque Loss ◽  
Torque Values

To evaluate torque loss a week after insertion, both in an in vivo and an in vitro experimental setup were designed. In the in vivo setup a total of 29 miniscrews were placed in 20 patients who underwent orthodontic treatment. Maximum insertion torque (MIT) was evaluated at insertion time (T1). A week later, insertion torque was measured again by applying a quarter turn (T2); no load was applied on the screw during the first week. In the in vitro setup a total of 20 miniscrews were placed in pig rib bone samples. MIT was evaluated at insertion time (T1). Bone samples were kept in saline solution and controlled environment for a week during which the solution was refreshed every day. Afterwards, torque was measured again by applying a quarter turn (T2). The comparison of MIT over time was done calculating the percentage difference of the torque values between pre- and post-treatment and using the parametric two independent samples t-test or the non-parametric Mann–Whitney test. After a week unloaded miniscrews showed a mean loss of rotational torque of 36.3% and 40.9% in in vitro and in in vivo conditions, respectively. No statistical differences were found between the two different setups. Torque loss was observed after the first week in both study models; in vitro experimental setup provided a reliable study model for studying torque variation during the first week after insertion.

scholarly journals The Effect of Glaze Coating on Wear Resistance of Some Acrylic Denture Teeth: An In Vitro Study

2021 ◽  
Vol 13 (2) ◽  
pp. 47-51
Author(s):  
Samaneh Abbasi ◽  
Soodabe Ebrahimi ◽  
Arash Shisheian ◽  
Maryam Farhadian
Keyword(s):  
Wear Resistance ◽  
In Vitro Study ◽  
Resistance Rate ◽  
Vitro Study ◽  
Wear Rates ◽  
Denture Teeth ◽  
Significant Difference ◽  
The Mean ◽  
Post Hoc

Background: Acrylic resin teeth wear resistance has an important role in the denture longevity. This study aimed to clarify the effect of glaze coating on wear resistance of three types of artificial acrylic teeth. Methods: In this in vitro study, the wear resistance rate of three of acrylic denture teeth (GENIUS, STON and CLASSIC) was compared with Ivoclar teeth (n=25/group). The wear resistance was measured by estimating the weight loss in pre and post removing glaze coating, following 5000 cycles in the chewing simulator device. Data analysis was made using paired t test, one-way ANOVA and Tukey’s post hoc test. Results: ANOVA test showed that there was no significant difference between the mean amount of wear of GENIUS, CLASSIC, STON and IVOCLAR teeth in the first stage (P <0.061), but this difference was significant (P <0.001) in the second stage. The result of Tukey post hoc test showed that wear rates of GENIUS were significantly lower than other groups (P<0.001). Comparison between the mean wear rates of each dental group at the first and second stages showed a significant difference between average teeth wear resistance of CLASSIC, STON and IVOCLAR in the first and second stages (P <0.001). Conclusions: In conclusion, the teeth wear resistance of STON and CLASSIC were similar to IVOCLAR. Also, after removing the glaze coating, the teeth wear resistance decreased in all groups but was not statistically significant for group GENIUS.

scholarly journals A Comparative Evaluation of Static Frictional Resistance Using Various Methods of Ligation at Different Time Intervals: An In Vitro Study

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Amanpreet Singh Natt ◽  
Amandeep Kaur Sekhon ◽  
Sudhir Munjal ◽  
Rohit Duggal ◽  
Anup Holla ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Artificial Saliva ◽  
In Vitro Study ◽  
Frictional Resistance ◽  
Static Friction ◽  
Significant Difference ◽  
Dry Conditions ◽  
The Mean ◽  
Time Periods

Aim. To compare and evaluate the static frictional resistance offered by the four different types of ligation methods in both dry and wet conditions and at different durations when immersed in artificial saliva.Material and Methods. Alastik Easy to Tie modules, Super Slick Mini Stix elastomeric modules, Power “O” modules, and 0.009″Stainless Steel ligatures were used to compare the static friction using maxillary canine and premolar Preadjusted Edgewise brackets with 0.022″× 0.028″slot and 0.019″× 0.025″stainless steel wires.Results. The mean frictional resistance for Alastik modules was the lowest and that of Stainless Steel ligatures was found to be highest among the four groups compared and the difference among the four groups was statistically significant (P<0.005). The mean static frictional resistance in all groups under dry conditions was lower than that under wet conditions. No statistical significant differences were found when the groups were compared at different time periods of immersion in artificial saliva.Conclusion. This study concludes that the Alastik modules showed the lowest mean static frictional forces compared to any other ligation method, though no significant difference was found for different time periods of immersion in the artificial saliva.

scholarly journals Comparative Analysis of the Stability of Prosthetic Screws under Cyclic Loading in Implant Prosthodontics: An In Vitro Study

2020 ◽  
Author(s):  
Santo Catapano ◽  
Mattia Ferrari ◽  
Nicola Mobilio ◽  
Marco Montanari ◽  
Massimo Corsalini ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Significant Loss ◽  
Fixed Number ◽  
Edentulous Mandible ◽  
Significant Difference ◽  
Rehabilitation Model ◽  
Hybrid Prosthesis ◽  
Anchoring System ◽  
Torque Values

Background: To compare the loss of preload in absence of loading and after a fixed number of ideal masticatory cycles in two different connection systems using all-on-four prosthetic model. Methods: Two equal models of an edentulous mandible rehabilitated with all-on-four technique with two types of abutment system (MUA and OT-Bridge) supporting a hybrid prosthesis, were used. Initial torque values of the prosthetic fixing screw, after ten minutes from initial screw tightening and after 400000 masticatory cycles were registered using a mechanical torque gauge. Differences between initial and final torque values were reported for each anchoring system and the two systems were finally compared. Results: No statistically significant differences regarding the loss of preload between MUA and OT-Bridge system were found after 400000 masticatory cycles; however, in MUA system it was found between anterior and posterior implant screws. A significant difference in preload loss was found only for MUA system comparing the initial screw torque to that measured after 10 minutes from the tightening in absence of cyclic loadings. Conclusions: MUA and OT-Bridge are reliable prosthetic anchoring systems able to tolerate repeated masticatory cycles also on distal cantilever in all-on-four rehabilitation model without any significant loss of preload in screw tightening

scholarly journals Estimation of Total Fluoride Concentration, Total Soluble Fluoride Concentration and pH among Various Brands of Toothpastes

2021 ◽  
Author(s):  
Praneetha D Rani ◽  
Vijaya Hegde
Keyword(s):  
Group Analysis ◽  
Fluoride Concentration ◽  
In Vitro Study ◽  
Significant Difference ◽  
The Mean ◽  
The Difference ◽  
Institute Of Technology ◽  
Level Of Significance ◽  
Post Hoc

Introduction: Fluoride toothpastes are a major reason for the decline in dental caries globally. For fluoride toothpaste to be effective, an adequate amount of Total Soluble Fluoride (TSF) must be available in the toothpastes. Aim: To determine and compare the Total Fluoride (TF), TSF and pH among various toothpaste brands. Materials and Methods: An in-vitro study was conducted during October 2019 on 20 toothpaste samples, which belonged to four groups namely, herbal toothpastes group, nonherbal toothpastes group, medicated toothpastes group and kids toothpastes group. Analysis of the samples was done at the Department of Environmental Engineering Laboratory, National Institute of Technology, Surathkal, Karnataka, India. The TF and the TSF concentration was determined using fluoride ion electrode. The pH was determined using pH meter. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS version 19.0). Analysis of variance (ANOVA) was used by Tukey’s post-hoc test to determine the difference between groups. The level of significance was kept at 0.05. Results: The results showed that there was a significant difference between the toothpaste types for mean TF concentration (p=0.004). The post-hoc test showed that there was a significant difference between herbal and nonherbal toothpastes (p=0.041) where the mean TF concentration for nonherbal toothpastes was 1095.20 ppm when compared to herbal toothpastes was 704.40 ppm. The results showed that there was a siginificant difference between the toothpaste types for Mean TSF concentration (p<0.003). There was a significant difference between medicated and kids toothpastes (p=0.024) where the mean total soluble fluoride concentration for medicated toothpastes was 938.60 ppm when compared to the kids toothpastes was 521.20 ppm. Conclusion: The present study showed that pH of all the toothpastes were either neutral or alkaline and the TSF concentration was less when compared to TF concentrations.

scholarly journals Evaluation of Microshear Bond Strength of Self-Adhesive Versus Conventional Flowable Resin Composite to Sound and Affected Dentin: An In Vitro Study

2021 ◽  
Vol 11 (4) ◽  
pp. 306-312
Author(s):  
Dalia M. Abouelmagd ◽  
Hanan K. Abouelseoud
Keyword(s):  
Bond Strength ◽  
Resin Composite ◽  
In Vitro Study ◽  
Vitro Study ◽  
Flowable Composite ◽  
Significant Difference ◽  
The Mean ◽  
Microshear Bond Strength ◽  
Vertise Flow

Objectives: This study aimed to compare the microshear bond strength (µSBS) of self-adhesive flowable composite and conventional bonded flowable composite to sound and caries affected dentin. Materials and Methods: In this in vitro study, a total of freshly extracted 40 human molar teeth were used. The occlusal surface was sectioned to expose dentin for µSBS test. The teeth were randomly divided into 2 groups according to the type of flowable composite used into two groups (n=20): group A: self- adhesive flowable composite (Vertise flow), group B: Filtek Z350-XT flowable composite and one-step self-etch adhesive Adper Easy One. A plastic cylindrical mold was used to construct resin composite cylinders (0.8mm diameter x 1mm length) on the sound and caries affected exposed dentin and filled with flowable composite restorative materials according to manufacturer’s instructions. The samples were then immersed in distilled water at 37°C for 24 hours, and underwent µSBS test at a crosshead speed of 0.5 mm/min. Data were analyzed using Student's t-test to compare between the two materials as well as to compare between sound and caries affected dentin. Results: The mean values of µSBS of Filtek Z-350XT to sound and caries affected were 26.6 and 26.7 MPa respectively. The mean µSBS of Vertise Flow to sound and affected were 13.2 and 17.9 MPa respectively. With sound dentin FiltekZ-350XT showed statistically significant higher µSBS than Vertise flow. With caries affected dentin, there was no statistically significant difference between the two materials. There was no statistically significant difference between µSBS of sound and caries affected dentin within each material. The significance level was set at P ≤ 0.05. Conclusions: Within the limitations of this study, the conventional flowable composite yielded the highest µSBS to sound dentin. There was no statistical significant difference in µSBS of self-adhesive and conventional flowable to caries affected dentin. Key words: Composite Resins; Dentin; microshear.

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