The influence of enamel sandblasting on the shear bond strength and fractography of the bracket-adhesive-enamel complex tested in vitro by the DIN 13990:2017-04 standard

Abstract

OBJECTIVES This study was conducted in order to investigate whether enamel sandblasting as an adjunct or substitute to the acid-etch technique has an effect on the shear bond strength (SBS) and fractography of the bracket-adhesive-enamel complex using the DIN 13990:2017-04 standard. MATERI-ALS AND METHODS Upper central incisor brackets (discovery®, Dentaurum, Germany) were bonded using Transbond XT™ (3M Unitek, Germany) on bovine incisors prepared by four different methods (15 samples each): sandblasting with 27 m AlO at 1.2 bar (s), acid etching with 37.4% phosphoric acid (a), sandblasting with 27 m AlO at 1.2 bar followed by acid etching (s1a), and sandblasting with 50 m AlO at 5.7 bar followed by acid etching (s2a). The SBS and adhesive remnant index (ARI) were measured, followed by one-way analysis of variance and Fisher's exact tests at 5%. RESULTS The SBS in groups s (5.6 ± 2.2 MPa), a (17.1 ± 4.3 MPa), s1a (18.3 ± 4.3 MPa), and s2a (18.5 ± 4.6 MPa) indicated that the s group was significantly inferior to all the other groups (p < 0.001). Likewise, the ARI analysis indicated a different performance of the s group (mostly ARI of 0) compared to the other groups (p < 0.001) and a tendency for different ARI between the a and s1a/s2a groups. CONCLUSIONS In vitro enamel sandblasting could not substitute acid etching and did not offer improved SBS when used before acid etching, regardless of air pressure and powder granulation. Sandblasting without acid etching produced less residual resin on the tooth after debonding. CLINICAL RELEVANCE The clinical use of adjunct enamel sandblasting prior to etching to enhance SBS has to be questioned. Abstract Objectives: To investigate by the DIN 13990:2017-04-standard, whether enamel sandblasting as an adjunct or substitute to the acid-etch technique has an effect on the shear bond strength (SBS) and fractography of the bracket-adhesive-enamel complex. Materials and Methods: Upper central incisor brackets (discovery®, Dentaurum, Germany) were bonded using Transbond XT™ (3M Unitek, Germany) on bovine incisors prepared by four different methods (15 samples each): sandblasting with 27 μm Al2O3 at 1.2 bar (s), acid etching with 37.4 % phosphoric acid (a),sandblasting with 27 µm Al2O3 at 1.2 bar followed by acid etching (s1a) and sandblasting with 50 μm Al2O3 at 5.7 bar followed by acid etching (s2a). The SBS and Adhesive-Remnant-Index (ARI) were measured, followed by one-way analysis of variance and Fisher's exact tests at 5%. Results:The SBS in the groups s (5.6±2.2 MPa), a (17.1±4.3 MPa), s1a (18.3±4.3 MPa) and s2a (18.5±4.6 MPa) indicated that the s group was significantly inferior to all other groups (p<0.001). Likewise, the ARI analysis indicated different performance of the s group (mostly ARI of 0) compared to the other groups (P<0.001) and a tendency for different ARI between the a and s1a/s2a groups. Conclusions:In-vitro enamel sandblasting could not substitute acid etching and did not offer improved SBS when used before acid etching, regardless of air pressure and powde...

Effect of surface treatments on the adhesive properties of metallic brackets on fluorotic enamel

“…Regarding the use of sandblasting, controversial results for bond strength values were observed in the literature when sound and fluorotic teeth where compared. 9 , 14 , 18 , 28 - 30 It has been suggested that sandblasting of enamel in association with phosphoric acid removes oxides and contaminants from teeth surface, increasing the total energy surface and roughness. 9 This effect could be partially showed when observing the microscopy evaluation for sound and fluorotic enamel.…”

Effect of the caries-protective self-assembling peptide P11-4 on shear bond strength of metal brackets

“…However, there are heterogeneous results about its effectiveness. In a study by Daratsianos et al [14] sandblasting could not substitute acid etching and did not offer improved shear bond strength when used before acid etching. Reicheneder et al [43] found increased shear bond strength values after pretreatment of enamel by sandblasting.…”

“…Many studies focused on the influence of different pretreatment procedures on the shear bond strength such as sandblasting [ 14 , 43 ] or application of different remineralization agents [ 36 ]. The sandblasting of enamel prior to bracket placement is commonly used to increase the shear bond strength and as a measure to reduce bracket failure rate.…”

Analysing the potential of hydrophilic adhesive systems to optimise orthodontic bracket rebonding

“…Teeth were randomly divided into groups, cleaned (SuperPolish™, Kerr Dental, Rastatt, Germany), rinsed and dried for further processing. Sample size was set to 20 specimens per group in accordance to the DIN-13990 standard that requires a minimum of 10 specimens and previous in vitro studies investigating shear bond strength [16,33]. The trial consisted of three parts.…”

“…Since premature bracket loss can lead to unwanted tooth movement and prolonged treatment duration, immediate rebonding is required [ 16 , 17 ]. Different rebonding procedures are described: clinicians either re-use the failed bracket or they bond a new bracket.…”