Direct technique premolar coronal restorations: From metallic material to "complete adhesive restoration".

Introduction: The choice of restorative materials has for a long time been determined by the tooth position. Thus, premolar restoration depended on the practitioner's clinical assessment and practical experience in regard to the material to be handled.

Aim: The objective of this study was to assess, in the students' practice, the change in the choice of materials used for premolars restoration.

Materials And Methods: This was a retrospective study based on the available care records in the department of conservative dentistry and endodontics of a dental school. Variables analyzed included the year of restoration, the type of material, the premolar position in the arch, and the coronal restoration site (occlusal, proximal, and cervical). Data collected were processed with the SPSS software version 22 (SPSS Inc., Chicago, IL, USA; 2013). The statistical significance threshold was set at 5% for Pearson's Chi-square test.

Results: Between 1994 and 2017, 1738 restored premolars were identified. Over the years, amalgam restorations declined from 99.2% in 1994 to 1.3% in 2017, contrary to composite whose frequency increased from 0.6% to 88.6%. Maxillary premolars were exclusively restored with composite in 2017 when amalgam was still, somewhat, used for mandibular premolars.

Conclusion: The reversal in the choice of materials in favor of composites reflects the global trend. This seems to be related to the current awareness of the prohibition, among others, of medical devices containing mercury.