Polishing methods for composites restoration: the influence on human gingival fibroblasts behaviour.

BACKGROUND: Carious/Non-carious cervical lesions with gingival recessions may require both dental and periodontal reconstructive therapy, where flaps/grafts may be placed in contact with a dental filling material. Human Gingival Fibroblasts (HGF-1) response during the early phase of healing could vary according to the procedures employed to cure the dental composite. Moreover, oxygen diffusion into dental composite inhibits the polymerization reaction, creating an oxygen-inhibited layer (OIL) that presents residual unreacted monomers. The aim of this study was to assess the effect of different polishing techniques and OIL on HGF-1. METHODS: Composite discs polished with different techniques (diamond rubber, abrasive discs and tungsten carbide burr) were used. An additional not polished smooth group obtained with and without OIL was used as control. Samples were physically characterized through the analysis of their hydrophilicity and surface topography through contact angle measurement and SEM, respectively; afterwards the biologic response of HGF-1 when cultured on the different substrates was analyzed in terms of cytotoxicity and gene expression. RESULTS: The finishing systems caused alterations to the wettability, even if without a proportional relation towards the results of the proliferation essay, from which emerges a greater proliferation on surfaces polished with one-step diamond rubber and with abrasive discs as well as a direct effect of the glycerin layer, confirming that surface roughness can heavily influence the biological response of HGF-1. CONCLUSIONS: Surfaces wettability as well as cellular behavior seem to be affected by the selection of the finishing system used to lastly shape the restoration. Especially, the presence of OIL act as a negative factor in the regards of human gingival fibroblasts. The present study may provide the first clinical instruction regarding the best polishing system of composite material when the restoration is placed directly in contact with soft tissue cells. Understanding HGF-1 behavior can help identifying the polishing treatment for direct restoration of carious/non-carious cervical lesions associated with gingival recessions.

The top 100 most-cited articles in dentistry by authors with Italian affiliation.

INTRODUCTION: Analyzing highly-cited articles can provide a retrospective assessment of research evolution and predict future developments. The aim of this study was to carry out a bibliometric analysis of the 100 most-cited articles in dentistry by authors with an Italian affiliation. EVIDENCE ACQUISITION: All the articles published in journals indexed under the Scopus category "Dentistry" and with at least one author affiliated to any Italian institution were searched in September 2022. The 100 most-cited articles were selected and relevant data were extracted and summarized. The analysis of co-authorship at country level and co-occurrence of keywords was carried out. EVIDENCE SYNTHESIS: The 100 most-cited articles were published between 1976 and 2020. The number of citations ranged from 235 to 1683, with a mean of 361. The series included 25 citation classics (>400 citations). The majority of articles were classified as expert opinion/narrative reviews (N.=47). Almost half of the articles refer to three predominant disciplines which were implantology, periodontology and restorative dentistry. Only two articles were single-authored. In 30 articles, all the authors had an Italian affiliation and the US was the most frequent country for non-Italian authors. Only one article was published in journals owned by a non-Italian publisher. CONCLUSIONS: The present series of highly-cited articles confirms the important role of Italy in dental research. We found an absence of correlation between the level of evidence and the number of citations and a non-homogeneous distribution of highly-cited papers in the different dental disciplines. The majority of articles included in the series shared international co-authorship and were published in high-impact journals.