In vitro adherence of oral streptococci to zirconia core and veneering glass‐ceramics

Abstract

Plaque formation on dental ceramics may cause gingival inflammation and secondary caries. This in vitro study compared the susceptibility of various dental ceramics to adhere oral streptococci, and verified the influence of substratum surface roughness and surface hydrophobicity. Three zirconia ceramic materials and three veneering glass-ceramics were investigated. Fifteen test specimens were prepared for each material, polished, and surface roughness and hydrophobicity were determined. After incubation with artificial saliva (2 h, 37 degrees C) for pellicle formation, specimens were incubated with suspensions of Streptococcus gordonii DSMZ 6777, Streptococcus mutans DSMZ 20523, Streptococcus oralis DSMZ 20627, or Streptococcus sanguinis DSMZ 20068, respectively, for 2.5 h at 37 degrees C. Adherent bacteria were quantified using a fluorescence dye for viable cell quantification (Alamar Blue/Resazurin). Statistical analysis was performed using one- and two-way ANOVA and the Tukey-Kramer multiple comparison test for post hoc analysis (alpha < 0.05). Surface roughness and surface hydrophobicity differed significantly among the various ceramics; protein coating hydrophilized the surfaces, and led to a homogenization of the surface hydrophobicity of the various ceramics. Before protein coating, almost similar relative fluorescence intensities indicating similar adhesion of streptococci were found for the various ceramics; more distinct differences were observed after protein coating. Correlations between surface parameters and streptococcal adhesion were poor. Within the limitations of these experiments, the findings of this in vitro study indicate only little differences between zirconia and glass ceramic with regard to streptococcal adhesion. Judging from these results, it is unlikely that exposed zirconia surfaces yield more plaque than glass ceramic surfaces in vivo.

Adhesion of Streptococcus mutans to Zirconia, Titanium Alloy and some other Restorative Materials: “An in-vitro Study”

“…Rosentritt conducted an study about S. mutans adhesion on zirconia core and veneering ceramic and reported that there was only little difference between them which is in agreement with our results (16). Ssurface roughness and surface free energy are among the most important factors which may influence the bacterial adhesion (17)(18).…”

The clinical success of tooth‐ and implant‐supported zirconia‐based fixed dental prostheses. A systematic review

“…This is in contrast to what has been published for metalceramic implant-supported FDPs (43) and also in contrast to studies claiming a high risk of peri-implantitis (59). Ceramic materials have been found to accumulate less plaque and plaque with reduced vitality, compared to other restorative materials (60)(61)(62). The clinical significance is uncertain, however.…”

Microbiological and host factors are involved in promoting the periodontal failure of metaloceramic crowns

“…In recent years, many evidences demonstrating that the presence of a fixed prosthetic restoration enhances the risk of the onset of periodontal lesions have been collected [2,6]. The awareness of the importance of an abnormal subgingival microbiota in the etiology of periodontal disease and that of adhesion to the hard tissues in dental plaque formation inspired studies aimed to identify materials that were less prone to bacterial colonization [7][8][9] and more suitable to reconstruct normal dental anatomy [1,5]. Although useful to develop optimized materials and techniques, these studies often failed to take into consideration important biological and clinical aspects of the problem and consequently failed to completely unveil the question [6,[10][11][12].…”

“…However, many evidences that show the existence of a close relationship between the presence of fixed prosthetic restorations and an enhanced risk of periodontal infections have been collected [2,6]. A lot of researches were consequently addressed at studying different dental materials with respect to their susceptibility to colonization by selected bacterial species [7][8][9], their surface characteristics, and many technical aspects related to the possibility to reconstruct normal dental anatomy [1,5]. These studies, nevertheless, frequently do not adequately classify periodontal conditions and confuse mere gingival inflammation and periodontal breakdown, ultimately possibly leading to ambiguous conclusions [6,[10][11][12].…”