Limits...
Frictional resistance in monocrystalline ceramic brackets with conventional and nonconventional elastomeric ligatures.

Galvão MB, Camporesi M, Tortamano A, Dominguez GC, Defraia E - Prog Orthod (2013)

Bottom Line: SENT showed significantly greater frictional force than Inspire Ice brackets and Pure brackets with NCEL.A significantly greater amount of frictional force was generated with CEL when compared with NCEL for all the tested variables, with the exception of the Pure brackets with 0.012-in.Nonconventional elastomeric ligatures are able to reduce friction in monocrystalline ceramic brackets.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthodontic, University of Florence, Via Ponte di Mezzo 46/48, Florence, 50100, Italy. matteo_camporesi@yahoo.it.

ABSTRACT

Background: The objective of this study was to compare the frictional forces generated by three types of monocrystalline ceramic brackets coupled with conventional elastomeric ligatures (CEL) and nonconventional elastomeric ligatures (NCEL) during the alignment of apically displaced teeth at the maxillary arch.

Methods: All tests (a total of 480 tests) were carried out in a dry state on a universal testing machine with a testing model consisting of three 0.022-in. monocrystalline ceramic preadjusted brackets (from the maxillary right second premolar through the right central incisor). The canine bracket was bonded to a sliding bar that allowed for different vertical positions. The frictional forces generated by a 0.012- and 0.014-in. superelastic nickel titanium wire (SENT) with conventional and nonconventional ligatures at various amounts of canine misalignment (1.5, 3.0, 4.5, and 6.0 mm) were recorded. Comparisons between the different types of bracket-wire-ligature systems were carried out by means of analysis of variance on ranks with Tukey's post hoc test (P<0.05).

Results: No significant differences were assessed among the three types of monocrystalline brackets with NCEL when coupled with 0.012-in. SENT. Radiance brackets with NCEL coupled with 0.014-in. SENT showed significantly greater frictional force than Inspire Ice brackets and Pure brackets with NCEL. A significantly greater amount of frictional force was generated with CEL when compared with NCEL for all the tested variables, with the exception of the Pure brackets with 0.012-in. SENT at 1.5 and 3.0 mm of canine misalignment where similar frictional forces were found.

Conclusions: Nonconventional elastomeric ligatures are able to reduce friction in monocrystalline ceramic brackets.

Show MeSH

Related in: MedlinePlus

When movement is stopped, the Instron machine analyzes the same forces, butFf shows opposite direction.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4384920&req=5

Fig4: When movement is stopped, the Instron machine analyzes the same forces, butFf shows opposite direction.

Mentions: The forces developed by the testing unit consisting of wire, brackets, and elastomeric ligatures were measured under dry conditions and at room temperature (20°C ± 2°C) by means of an Instron 3365 testing machine (Instron Corp., Canton, MA, USA) with a load cell of 10 N. The upper end of the sliding bar bearing the canine bracket was connected to the Instron crosshead. The frictional forces were calculated as reported in the ‘Appendix’ (Figures 2, 3, 4). The frictional forces generated by each bracket-wire-ligature combination at the different amounts of vertical canine misalignment were tested ten times with new wires and new ligatures for each test. A total of 480 tests (240 tests with NCEL and 240 tests with CEL) were carried out.Figure 2


Frictional resistance in monocrystalline ceramic brackets with conventional and nonconventional elastomeric ligatures.

Galvão MB, Camporesi M, Tortamano A, Dominguez GC, Defraia E - Prog Orthod (2013)

When movement is stopped, the Instron machine analyzes the same forces, butFf shows opposite direction.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4384920&req=5

Fig4: When movement is stopped, the Instron machine analyzes the same forces, butFf shows opposite direction.
Mentions: The forces developed by the testing unit consisting of wire, brackets, and elastomeric ligatures were measured under dry conditions and at room temperature (20°C ± 2°C) by means of an Instron 3365 testing machine (Instron Corp., Canton, MA, USA) with a load cell of 10 N. The upper end of the sliding bar bearing the canine bracket was connected to the Instron crosshead. The frictional forces were calculated as reported in the ‘Appendix’ (Figures 2, 3, 4). The frictional forces generated by each bracket-wire-ligature combination at the different amounts of vertical canine misalignment were tested ten times with new wires and new ligatures for each test. A total of 480 tests (240 tests with NCEL and 240 tests with CEL) were carried out.Figure 2

Bottom Line: SENT showed significantly greater frictional force than Inspire Ice brackets and Pure brackets with NCEL.A significantly greater amount of frictional force was generated with CEL when compared with NCEL for all the tested variables, with the exception of the Pure brackets with 0.012-in.Nonconventional elastomeric ligatures are able to reduce friction in monocrystalline ceramic brackets.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthodontic, University of Florence, Via Ponte di Mezzo 46/48, Florence, 50100, Italy. matteo_camporesi@yahoo.it.

ABSTRACT

Background: The objective of this study was to compare the frictional forces generated by three types of monocrystalline ceramic brackets coupled with conventional elastomeric ligatures (CEL) and nonconventional elastomeric ligatures (NCEL) during the alignment of apically displaced teeth at the maxillary arch.

Methods: All tests (a total of 480 tests) were carried out in a dry state on a universal testing machine with a testing model consisting of three 0.022-in. monocrystalline ceramic preadjusted brackets (from the maxillary right second premolar through the right central incisor). The canine bracket was bonded to a sliding bar that allowed for different vertical positions. The frictional forces generated by a 0.012- and 0.014-in. superelastic nickel titanium wire (SENT) with conventional and nonconventional ligatures at various amounts of canine misalignment (1.5, 3.0, 4.5, and 6.0 mm) were recorded. Comparisons between the different types of bracket-wire-ligature systems were carried out by means of analysis of variance on ranks with Tukey's post hoc test (P<0.05).

Results: No significant differences were assessed among the three types of monocrystalline brackets with NCEL when coupled with 0.012-in. SENT. Radiance brackets with NCEL coupled with 0.014-in. SENT showed significantly greater frictional force than Inspire Ice brackets and Pure brackets with NCEL. A significantly greater amount of frictional force was generated with CEL when compared with NCEL for all the tested variables, with the exception of the Pure brackets with 0.012-in. SENT at 1.5 and 3.0 mm of canine misalignment where similar frictional forces were found.

Conclusions: Nonconventional elastomeric ligatures are able to reduce friction in monocrystalline ceramic brackets.

Show MeSH
Related in: MedlinePlus