Flowable composite an alternative orthodontic bonding adhesive: an in vitro study

Bruxism’s Implications on Fixed Orthodontic Retainer Adhesion

Background: Fixed retainers assist in maintaining the outcomes of orthodontic treatment. Fixed retention may be affected by bruxism. Objective: Evaluate two adhesives (an ormocer and a flowable composite) used for fixed orthodontic retention in simulated bruxism settings, compared to regular mastication, using a dual axis chewing simulator. Methods: Eighty human teeth were used. Periodontal tissues were simulated and exposed to 120,000 mechanical cycles, corresponding to 6 months of clinical service. Each set of two teeth was supplied with a pre-shaped, fixed, multi-braided, stainless steel wire retainer, in 1.5 cm portions, to establish passive contact with the lingual surface of the teeth. The Adhesive Remnant Index (ARI) was used to evaluate the shear bond strength. A stereomicroscope was used to assess the micro-infiltration. Results: There was no significant difference in the mean value of micro-infiltration between adhesives in the mastication group but in the bruxism group. During testing, one composite sample (ARI score 1) was broken in the mastication group, while three ormocer samples (ARI score 2) and one composite sample (ARI score 1) were broken in the bruxism group. Conclusions: The mean value for micro-infiltration in composite (0.31) was more than double that in ormocer (0.13).

An Evaluation of Shear Bond Strength of Admira (Ormocer) as an Alternative Material for Bonding Orthodontic Brackets: An In vitro Study

Objective:

To evaluate shear bond strength (SBS) of Ormocer-bonded orthodontic brackets with self-etching primer (SEP) and conventional adhesive system and also to assess the amount of adhesive remaining on the tooth surface after debonding using adhesive remnant index (ARI).

Materials and Methods:

The study was done on 90 extracted human upper first permanent maxillary premolars. The study sample was categorized into three groups of 30 each to assess the SBS using three adhesives, Ormocer, SEP, and conventional adhesive system. Following debonding, the surfaces of teeth were examined for residual adhesive remaining by means of the optical stereomicroscope at ×50 magnification. ARI (Artun and Bergland) was used to classify the amount of residual adhesive. Obtained data were expressed as mean ± standard deviation, and obtained data was expressed as mean ± standard deviation (SD) and statistical analysis was done using one way ANOVA and Mann-Whitney U-test [SPSS version 17 statistical package (SPSS Inc., Chicago, IL)].

Results:

The mean SBS was maximum in Group I followed by Group II and Group III. The difference in the mean SBS among Group I (8.67 ± 1.84 Mpa), Group II (7.72 ± 1.82 MPa) and Group III (6.42 ± 1.55 MPa) was statistically significant. ARI was maximum in Group I followed by Group II and minimum Group III.

Conclusion:

Ormocer may be utilized as a substitute to generally used bisphenol A-glycidyl methacrylate-based adhesives; however, its effectiveness should be determined clinically by in vivo studies.

"Ormocer an innovative technology": A replacement for conventional cements and veneer? A comparative in vitro analysis

Objective:

This in vitro study was designed to assess shear bond strength (SBS) of ormocer flowable (OF) resin as a luting agent, ormocer as an indirect veneer material with portrayal of modes of failures using scanning electron microscope (SEM).

Materials and Methods:

Sixty maxillary central incisors were divided into Group I, II, and III with 20 samples each based on luting cement used. They were OF, self-adhesive (SA) cement, and total etch (TE) cement. These groups were subdivided into “a” and “b” of ten each based on the type of veneering materials used. Veneer discs were fabricated using Ormocer restorative (O) and pressable ceramic (C). Specimens were thermocycled and loaded under universal testing machine for SBS. The statistical analysis was done using one-way ANOVA post hoc Tukey honest significant difference method.

Results:

A significant difference was observed between the Groups I and II (P < 0.05). The highest mean bond strength when using ormocer veneer was obtained with the Group Ia (19.11 ± 1.92 Mpa) and lowest by Group IIa (8.1 ± 1.04 Mpa), whereas the highest mean bond strength while using ceramic veneer was of similar range for Group Ib (18.04 ± 4.08 Mpa) and Group IIIb (18.07 ± 1.40 Mpa). SEM analysis revealed OF and TE presented mixed type of failure when compared with SA where failure mode was totally adhesive.

Conclusion:

OF was found equally efficient like TE. Bond strength of ormocer as a veneer was not inferior to ceramic making it one of the promising additions in the field of dentistry.