Biomedical subjects

Ilja Klück

Publications and source records attributed to Ilja Klück.

3 recordsLinked to original sources

PubMed2006

An in vitro microbial-based model for studying caries-preventive agents.

OBJECTIVE: The aim of the study was to develop an in vitro microbial-based caries model to test potentially caries-preventive agents. MATERIAL AND METHODS: In this model, cariogenic Streptococcus mutans biofilms are grown on tooth samples within a reaction chamber hermetically surrounded by a bacteria-tight glove box allowing the manipulation of specimens during operation. The specimens were mounted in two rows on the inner and outer rims of a specimen turntable passing several inlet pipes transporting all necessary media. Using 64 lower incisors in 4 experiments, a 10 ppm NaF solution and an experimental potentially caries-preventive glycan solution were tested compared to a water control. The mean lesion depth was determined by confocal laser scanning microscopy. RESULTS: The depths of the caries-like lesions showed no statistically significant difference irrespective of whether the specimens were mounted on the inner or outer rim of the specimen turntable. As expected, the NaF solution inhibited the development of caries-like lesions almost completely. The experimental glycan solution revealed a statistically significantly lower demineralization depth compared to the control and a significantly higher depth compared to the NaF group. The system could be operated over a period of more than 9 weeks without unintentional contamination and the manipulation of the tooth specimens could be accomplished. CONCLUSIONS: In conclusion, our in vitro system is suitable for testing potential caries-preventive agents in a reproducible way by using whole tooth samples and offers full access together with the possibility of manipulating the specimens during operation.

Biofilms↗

PubMed2006

Caries-preventive potential of an adhesive patch after thermomechanical loading--a microbial-based in vitro study.

PURPOSE: To assess the enamel-protective potential of a newly devised adhesive patch for smooth enamel sealing. MATERIALS AND METHODS: Approximal surfaces of 30 extracted molars were divided into three areas: the buccal thirds were treated with a flowable composite (Tetric Flow, Ivoclar Vivadent) and served as negative control sites, the lingual thirds were left untreated and served as positive control sites, and the middle thirds served as the test areas. This was sealed with either 1. a twofold application of an unfilled resin (Heliobond, Ivoclar Vivadent), 2. an adhesive prototype patch (Ivoclar Vivadent), or 3. an adhesive patch in combination with a flowable composite. After thermomechanical loading and demineralization in a microbial-based artificial caries chamber, demineralization depth was assessed using a confocal laser scanning microscope. RESULTS: Negative control sites treated with the flowable composite showed no signs of demineralization. Areas treated with the patch showed no signs of demineralization, irrespective of whether it was used in combination with a flowable composite or directly bonded to the enamel. Caries-like lesions in untreated sites showed a mean depth of 134.3 +/- 35.9 microm. Demineralization depth at sites treated with the unfilled resin was 76.2 +/- 26.5 microm (p = 0.023). CONCLUSIONS: Under the conditions of the present study, the adhesive patch under investigation completely protected the underlying enamel from demineralization. This merits further study to assess its potential as an interproximal sealant.

Adhesives↗

PubMed2004

Secondary caries-like lesions at fissure sealings with Xeno III and Delton--an in vitro study.

OBJECTIVES: The aim of the study was to establish a bacterial based in vitro caries model to test the caries preventive effect of fissure sealants and to investigate whether a self-etching adhesive (Xeno III) used as fissure sealant is equally effective in preventing secondary caries compared to a conventional sealant (Delton) when applied on saliva contaminated and non-contaminated fissures. METHODS: Forty caries-free upper premolars were randomly divided into two groups. Group A was sealed with a conventional resin-based fissure sealant (Delton) after phosphoric acid etching. Group B was sealed with a self-etching adhesive (Xeno III) without prior etching. To simulate the clinical situation of saliva contamination, the distal part of each tooth was slightly moistened with saliva before sealant application. After thermo-cycling, the specimens were exposed to a cariogenic Streptococcus mutans biofilm in an artificial mouth model. Depths of demineralization were measured on serial sections by confocal laser scanning microscopy. If a demineralization was detected underneath the whole fissure sealing the sample was rated as 'total failure'. RESULTS: Significantly higher numbers of total failures could be found in the Xeno III group compared to the Delton group in areas without saliva contamination. On contaminated areas, no significant difference could be found. There was no significant difference regarding the depth of the primary carious lesions between groups. CONCLUSION: The study supports our recent findings that our caries model is capable to produce secondary caries-like lesions at fissure sealings. Based on the present in vitro data, it cannot be recommended to use the self-etching adhesive Xeno III solely as a fissure sealant.

Acid Etching, Dental↗