Friction Forces during Sliding of Various Brackets for Malaligned Teeth: An In Vitro Study

Aims. To measure the friction force generated during sliding mechanics with conventional, self-ligating (Damon 3 mx, Smart Clip, and Time 3) and low-friction (Synergy) brackets using different archwire diameters and ligating systems in the presence of apical and buccal malalignments of the canine.Methods. An experimental setup reproducing the right buccal segment of the maxillary arch was designed to measure the friction force generated at the bracket/wire and wire/ligature interfaces of different brackets. A complete factorial plan was drawn up and a three-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect the values of friction force: (i) degree of malalignment, (ii) diameter of the orthodontic wire, and (iii) bracket/ligature combination. Tukey post hoc test was also conducted to evaluate any statistically significant differences between the bracket/ligature combinations analyzed.Results. ANOVA showed that all the above factors affect the friction force values. The friction force released during sliding mechanics with conventional brackets is about 5-6times higher than that released with the other investigated brackets. A quasilinear increase of the frictional forces was observed for increasing amounts of apical and buccal malalignments.Conclusion. The Synergy bracket with silicone ligature placed around the inner tie-wings appears to yield the best performance.

Download Full-text

In vitro study of frictional forces during sliding mechanics of “reduced-friction” brackets

American Journal of Orthodontics and Dentofacial Orthopedics ◽

10.1016/s0889-5406(03)00238-5 ◽

2003 ◽

Vol 124 (1) ◽

pp. 69-73 ◽

Cited By ~ 54

Author(s):

Meir Redlich ◽

Yaniv Mayer ◽

Doron Harari ◽

Israel Lewinstein

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Frictional Forces ◽

Sliding Mechanics

Download Full-text

An In Vitro Evaluation of Frictional Characteristics of Labial and Lingual Self-ligating Brackets with Various Archwire Alloys

The Journal of Indian Orthodontic Society ◽

10.1177/0301574220921383 ◽

2020 ◽

Vol 54 (3) ◽

pp. 203-213

Author(s):

Subrat Kumar Sahany ◽

G. Sreejith Kumar

Keyword(s):

Stainless Steel ◽

Frictional Force ◽

Testing Machine ◽

In Vitro Study ◽

Fixed Appliance ◽

Conventional Brackets ◽

Frictional Forces ◽

Dry And Wet Conditions ◽

Lingual Brackets

Background: An understanding of bracket slot–archwire interface is imperative for biomechanical effectiveness in orthodontic sliding mechanics and hence the aim of the study is to evaluate frictional properties of lingual self-ligating brackets comparing with conventional lingual and labial self-ligating brackets using three different archwire alloys in various environments. Materials and Methods: This in vitro study compared the frictional force of labial and lingual self-ligating and conventional lingual brackets with stainless steel, TMA, and Cr-Co alloy archwires of 0.017” × 0.025” dimension in dry and wet conditions. Frictional forces were evaluated in a simulated half arch fixed appliance using a testing machine. Static and kinetic friction were measured and analyzed by one-way analysis of variance (ANNOVA) test and post hoc Duncan multiple range test. The effects of brackets and archwires in dry and wet conditions were analyzed by three-way variance (ANNOVA) test. Result: The maximum frictional forces were observed with labial self-ligating brackets followed by lingual conventional brackets and the least by lingual self-ligating brackets. Of all the wires tested, TMA wires had the maximum frictional forces followed by Co-Cr and stainless steel. In both conditions, the values were non-significant with all bracket–wire combinations except with Co-Cr and TMA wires. Conclusions: Varied amount of frictional force was shown by the brackets and wires with highest by labial self-ligating bracket, followed by lingual conventional and lingual self-ligating brackets. TMA wires experienced higher friction followed by Co-Cr and stainless steel with minimum friction.

Download Full-text

Evaluation of the friction force generated by monocristalyne and policristalyne ceramic brackets in sliding mechanics

Dental Press Journal of Orthodontics ◽

10.1590/s2176-94512013000100023 ◽

2013 ◽

Vol 18 (1) ◽

pp. 121-127 ◽

Cited By ~ 3

Author(s):

Roberta Ferreira Pimentel ◽

Roberto Sotto Maior Fortes de Oliveira ◽

Maria das Graças Afonso Miranda Chaves ◽

Carlos Nelson Elias ◽

Marco Abdo Gravina

Keyword(s):

Friction Force ◽

Artificial Saliva ◽

Testing Machine ◽

Friction Coefficients ◽

Friction Forces ◽

Maximum Friction ◽

Steel Wires ◽

Ceramic Brackets ◽

Sliding Mechanics

OBJECTIVE: To evaluate and compare "in vitro" the maximum friction force generated by three types of esthetic brackets, two types of polycrystalline conventional ceramic brackets (20/40 and InVu) and one type of sapphire monocrystalline bracket (Radiance) in dry and artificial saliva wet settings. Also, to evaluate the influence exerted by artificial saliva on the friction forces of those brackets. METHODS: Tests were performed in dry and artificial saliva wet setting (Oral Balance) by using an EMIC DL 10000 testing machine, simulating a 2 mm slide of 0.019 x 0.025-in rectangular stainless steel wires over the pre-angulated and pre-torqued (right superior canine, Roth prescription, slot 0.022 x 0.030-in) brackets (n = 18 for each bracket). In order to compare groups in dry and wet settings, the ANOVA was used. For comparisons related to the dry versus wet setting, the student t test was used for each group. RESULTS: The results showed that in the absence of saliva the Radiance monocrystalline brackets showed the highest friction coefficients, followed by the 20/40 and the InVu polycrystalline brackets. In tests with artificial saliva, the Radiance and the 20/40 brackets had statistically similar friction coefficients and both were greater than that presented by the InVu brackets. The artificial saliva did not change the maximum friction force of the Radiance brackets, but, for the others (20/40 and InVu), an increase of friction was observed in its presence. CONCLUSION: The InVu brackets showed, in the absence and in the presence of saliva, the lowest friction coefficient.

Download Full-text

Evaluation of the Friction of Self-Ligating and Conventional Bracket Systems

European Journal of Dentistry ◽

10.1055/s-0039-1698897 ◽

2011 ◽

Vol 05 (03) ◽

pp. 310-317 ◽

Cited By ~ 10

Author(s):

Simona Tecco ◽

Donato Di Iorio ◽

Riccardo Nucera ◽

Beatrice Di Bisceglie ◽

Giancarlo Cordasco ◽

...

Keyword(s):

In Vitro Study ◽

P Value ◽

Low Friction ◽

Experimental Conditions ◽

Beta Titanium ◽

Conventional Brackets ◽

Orthodontic Archwires ◽

Post Hoc ◽

Conventional Bracket

ABSTRACTObjectives: This in vitro study evaluated the friction (F) generated by aligned stainless steel (SS) conventional brackets, self-ligating Damon MX© brackets (SDS Ormco, Glendora, California, USA), Time3© brackets (American Orthodontics, Sheboygan, Wisconsin, USA), Vision LP© brackets (American Orthodontics), and low-friction Slide© ligatures (Leone, Firenze, Italy) coupled with various SS, nickel-titanium (NiTi), and beta-titanium (TMA) archwires. Methods: All brackets had a 0.022-inch slot, and the orthodontic archwires were 0.014-inch, 0.016-inch, 0.014×0.025-inch, 0.018×0.025-inch, and 0.019×0.025-inch NiTi; 0.017×0.025-inch TMA; and 0.019×0.025-inch SS. Each bracket-archwire combination was tested 10 times. In the test, 10 brackets of the same group were mounted in alignment on a metal bar. The archwires moved through all the 10 brackets at a crosshead speed of 0.5 mm/min (each run lasted approximately 5 min). The differences among 5 groups of brackets were analyzed through the Kruskal-Wallis test, and a Mann-Whitney test was calculated as post hoc analysis. The P value was set at 0.05. Results: Coupled with 0.014-inch NiTi and 0.016-inch NiTi, Victory Series© brackets generated the greatest F, while Damon MX© and Vision LP© brackets generated the lowest (P<.05); no significant differences were observed between Time3© brackets and Slide© ligatures. Coupled with all the rectangular archwires, Victory Series© brackets, Slide© ligatures, and Vision LP© self-ligating brackets generated significantly lower F than did Time3© and Damon MX© self-ligating brackets (P<.05). Conclusions: These findings suggest that self-ligating brackets are a family of brackets that, in vitro, can generate different levels of F when coupled with thin or thick, rectangular, or round archwires. Clinical conclusions based on our results are not possible due to the limitations of the experimental conditions. (Eur J Dent 2011;5:310-317)

Download Full-text

Streptococcus mutans adherence to conventional and self-ligating brackets: an in vitro study

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.26.6.e212019.oar ◽

2021 ◽

Vol 26 (6) ◽

Author(s):

Murilo Fernando Neuppmann FERES ◽

Fernanda VICIONI-MARQUES ◽

Fábio Lourenço ROMANO ◽

Marina Guimarães ROSCOE ◽

Vinícius Matsuzaki de SOUZA ◽

...

Keyword(s):

Streptococcus Mutans ◽

Bacterial Adhesion ◽

In Vitro Study ◽

Vitro Study ◽

Bacterial Suspension ◽

Colony Forming Units ◽

Conventional Brackets ◽

Adhesion Rate ◽

Post Hoc

ABSTRACT Introduction: Although self-ligating brackets presumably provide better hygiene conditions, no consensus has been reached so far. Objective: Therefore, the objective of this study was to evaluate, in an in vitro experimental design, the adherence of Streptococcus mutans (SM) in self-ligating and conventional brackets of different manufacturers and ligature types. Methods: Four commercial brands of maxillary premolar metal brackets were tested (Abzil®; Morelli®; 3M Unitek®; and GAC®). Each one was subdivided into three groups, which varied according to the type of ligature and bracket model (metallic, elastic, and self-ligating), totalizing twelve groups, composed of six brackets each. Previously sterilized brackets were initially immersed in saliva for one hour, and subsequently washed and added in a bacterial suspension, maintained in aerobiosis for 72 hours. The adhered bacteria were then separated and quantified by colony forming units (CFU/mL) counting after 48 hours of growth. The groups were compared by Kruskal-Wallis and Dunn post-hoc tests (p< 0.05). Results: Regardless of the commercial brand, self-ligating brackets had significantly less CFU/mL. However, according to comparisons performed within each commercial brand, only Abzil® self-ligating brackets had significantly lower biofilm adhesion. Among all of the self-ligating models, GAC® brackets presented the highest bacterial adhesion rate. Conclusions: Self-ligating brackets are likely to present lower rates of biofilm adhesion. Particularly, Abzil® and GAC® self-ligating brackets are less likely to accumulate biofilm. Although such results are derived from an in vitro study, practitioners might acknowledge findings concerning bacterial adhesion as one of the relevant features to be considered during bracket selection.

Download Full-text

Evaluation of friction on self-ligating and conventional brackets associated with different types of archwires submitted to sliding mechanics

Brazilian Journal of Oral Sciences ◽

10.20396/bjos.v18i0.8657258 ◽

2019 ◽

Vol 18 ◽

pp. e191605

Author(s):

William Carlos Silva Barbosa ◽

Américo Bortolazzo Correr ◽

Diego Patrik Alves Carneiro ◽

Mário Vedovello Filho ◽

Ana Paula Terossi de Godoi ◽

...

Keyword(s):

Stainless Steel ◽

Frictional Force ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

In Vitro Study ◽

Nickel Titanium ◽

Copper Nickel ◽

Conventional Brackets ◽

Sliding Mechanics

Aim: The aim of this study was to verify the frictional force during sliding mechanics in orthodontic tooth movement, using conventional metal brackets of the active and passive self-ligating types with stainless steel and copper nickel titanium archwires. Methods: This experimental in vitro study was conducted with conventional metal (Morelli, Sorocaba, SP, Brazil) brackets, active self-ligated (SLI Morelli, Sorocaba, SP, Brazil) and passive self-ligated (SLP Morelli, Sorocaba, SP, Brazil), with slot 0.022 x 0.028 inches and Roth prescription. The brackets were tested with rectangular section 0.019 x 0.025 inch copper nickel titanium and stainless steel archwires. For each type of bracket, 10 sets of plate/bracket/archwire segment (n=10) were fabricated. Non-parametric Kruskal Wallis and Dunn tests were used for comparison between types of brackets and Wilcoxon tests for comparison between types of archwires. Results: The results showed that the frictional force values were higher with copper nickel titanium than with stainless steel archwires (p<0.05). When copper nickel titanium archwires were used, the active self-ligating brackets showed higher frictional force values than the other types, followed by the conventional brackets. Lower frictional force values were observed with passive self-ligating brackets. For stainless steel archwires, no difference was observed between conventional and active self-ligating brackets, the passive self-ligating type presented lower frictional force values than the others. Conclusion: It was concluded that the higher frictional force was observed when active self-ligating brackets were associated with copper nickel titanium archwires. Lower frictional force was verified between passive self-ligating brackets combined with stainless steel archwires.

Download Full-text

Tooth discoloration induced by apical plugs with hydraulic calcium silicate-based cements in teeth with open apices—a 2-year in vitro study

Clinical Oral Investigations ◽

10.1007/s00784-021-04009-0 ◽

2021 ◽

Author(s):

Ralf Krug ◽

C. Ortmann ◽

S. Reich ◽

B. Hahn ◽

G. Krastl ◽

...

Keyword(s):

Calcium Silicate ◽

In Vitro Study ◽

Color Difference ◽

Blood Contamination ◽

Tooth Color ◽

Color Changes ◽

Gutta Percha ◽

Tooth Discoloration ◽

Post Hoc

Abstract Objectives To assess tooth discoloration induced by different hydraulic calcium silicate-based cements (HCSCs), including effects of blood and placement method. Materials and methods Eighty bovine teeth cut to a length of 18 mm (crown 8 mm, root 10 mm) were randomly assigned to 10 groups (n = 8), receiving orthograde apical plug treatment (APT). Apical plugs were 4 mm in length and made of ProRoot MTA (Dentsply), Medcem MTA (Medcem), TotalFill BC RRM Fast Set Putty (Brasseler), or Medcem Medical Portland Cement (Medcem) plus bismuth oxide (Bi2O3) with and without bovine blood. Further, orthograde (with or without preoperative adhesive coronal dentin sealing) and retrograde APT were compared. Teeth were obturated with gutta-percha and sealer, sealed with composite and stored in distilled water. Tooth color was measured on apical plug, gutta-percha/sealer, and crown surface before treatment versus 24 h, 1, 3, 6, 12, and 24 months after treatment by spectrophotometry. Color difference (ΔE) values were calculated and analyzed by Shapiro–Wilk test, ANOVA with post hoc tests, Friedman test, t test, and post hoc tests with Bonferroni correction (α = .05). Results Tooth discoloration occurred in all groups with no significant differences between HCSCs (p > .05). After 24 months, color changes were prominent on roots but insignificant on crowns. Blood contamination induced a significantly decreased luminescence (p < .05). Blood had a stronger impact on tooth color than Bi2O3. No relevant effects of retrograde placement (p > .05) or preoperative dentin sealing (p > .05) were detected. Conclusions Apical plugs of the tested HCSCs cause discoloration of bovine roots, but not discoloration of bovine tooth crowns within a 24-month period. Clinical relevance APT should be performed carefully while avoiding direct contact with the coronal dentin, and in that case no aesthetic impairments occur.

Download Full-text

Potential of different fluoride gels to prevent erosive tooth wear caused by gastroesophageal reflux

BMC Oral Health ◽

10.1186/s12903-021-01548-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Philipp Körner ◽

Luca Georgis ◽

Daniel B. Wiedemeier ◽

Thomas Attin ◽

Florian J. Wegehaupt

Keyword(s):

Gastroesophageal Reflux ◽

Artificial Saliva ◽

In Vitro Study ◽

Tooth Wear ◽

Control Group ◽

Erosive Tooth Wear ◽

Custom Made ◽

Post Hoc ◽

Bovine Enamel

Abstract Background This in-vitro-study aimed to evaluate the potential of different fluoride gels to prevent gastroesophageal reflux induced erosive tooth wear. Methods Surface baseline profiles of a total of 50 bovine enamel specimens [randomly assigned to five groups (G1–5)] were recorded. All specimens were positioned in a custom made artificial oral cavity and perfused with artificial saliva (0.5 ml/min). Reflux was simulated 11 times a day during 12 h by adding HCl (pH 3.0) for 30 s (flow rate 2 ml/min). During the remaining 12 h (overnight), specimens were stored in artificial saliva and brushed twice a day (morning and evening) with a toothbrush and toothpaste slurry (15 brushing strokes). While specimens in the control group (G1) did not receive any further treatment, specimens in G2–5 were coated with different fluoride gels [Elmex Gelée (G2); Paro Amin Fluor Gelée (G3); Paro Fluor Gelée Natriumfluorid (G4); Sensodyne ProSchmelz Fluorid Gelée (G5)] in the evening for 30 s. After 20 days, surface profiles were recorded again and enamel loss was determined by comparing them with the baseline profiles. The results were statistically analysed using one-way analysis of variance (ANOVA) followed by Tukey`s HSD post-hoc test. Results The overall highest mean wear of enamel (9.88 ± 1.73 µm) was observed in the control group (G1), where no fluoride gel was applied. It was significantly higher (p < 0.001) compared to all other groups. G2 (5.03 ± 1.43 µm), G3 (5.47 ± 0.63 µm, p = 0.918) and G4 (5.14 ± 0.82 µm, p > 0.999) showed the overall best protection from hydrochloric acid induced erosion. Enamel wear in G5 (6.64 ± 0.86 µm) was significantly higher compared to G2 (p = 0.028) and G4 (p = 0.047). Conclusions After 20 days of daily application, all investigated fluoride gels are able to significantly reduce gastroesophageal reflux induced loss of enamel.

Download Full-text