Compressive Strength Testing of Glass-Fibre-Reinforced Tooth Crown Tissues After Endodontic Treatment.

The objective of this study was to compare the effects of using short and continuous fibres for repairing compression-induced tooth crown damage. Human teeth were used for the study. They were upper medial incisors and maxillary first premolars lost due to periodontal causes. The teeth were divided into two groups with Hahnenkratt and short glass fibres. Teeth compressive strength tests were carried out. Then micro-CT imaging of the teeth and their fractures obtained after compression was performed. The teeth restored with Hahnenkratt's glass fibre posts showed higher compressive strength than the teeth restored using the EverX Posterior material. The tooth's most weakened and sensitive point after endodontic treatment was the cervical area of the tooth. All cracks were parallel to the root canal.

Qualitative analysis of the margins of restorations made with different filling resins.

PURPOSE: In this study the comparative results obtained from examinations of two different restorative composites with different cavities filling method are presented. Micro-CT was used for the evaluation of the marginal integrity and quality of composite fillings in connection with microstructural investigations made by both optical and scanning electron microscopy. MATERIALS AND METHODS: The examinations of dental tooth filings in bulk-fill technique were based on micro-CT and microscopy observations. Two different restorative composites were selected for the study, namely SonicFill- bulk fill and conventional Filtek Z550. RESULTS: The experiment has shown that micro-CT screening analysis for identification of individual components of tooth and fillings systems gives a high quality of images. Thanks to that it was possible to analyze and identify the porosity in the fillings. But the microscopy analysis has shown more information about the internal structure and quality of bonding between composite and enamel/dentin. The SonicFill gives better quality and bonding to structure of teeth than Filtek. CONCLUSIONS: SonicFill's filling have more homogenous structure than Filtec. It has a greater share of reinforcement in the form of polygonal particles, in Filtek particles have a shape close to spherical. Sonic Fill gives a better adhesion to tooth. CLINICAL RELEVANCE: The evaluation of clinical relevance in this research is crucial to simplify the transfer of knowledge from research by materials engineering into practice in dentistry.

Evaluation of marginal integrity of four bulk-fill dental composite materials: in vitro study.

OBJECTIVE: The aim of the study was to compare under in vitro conditions marginal sealing of 4 different bulk-fill materials composite restorations of class II. METHODS: Comparative evaluation concerned 4 composites of a bulk-fill type: SonicFill, Tetric EvoCeram Bulk Fill, Filtek Bulk Fill, and SDR. The study used 30 third molars without caries. In each tooth 4 cavities of class II were prepared. The prepared tooth samples were placed in a 1% methylene blue solution for 24 h, and after that in each restoration the depth of dye penetration along the side walls was evaluated. RESULTS: The highest rating (score 0, no dye penetration) was achieved by 93.33% of the restorations made of the SDR material, 90% of restorations of SonicFill system, 86.66% of restorations of the composite Filtek Bulk Fill, and 73.33% of restorations of the Tetric EvoCeram Bulk Fill. CONCLUSION: The performed study showed that bulk-fill flowable or sonic-activated flowable composite restorations have better marginal sealing (lack of discoloration) in comparison with bulk-fill paste-like composite.

Evaluation of millers' dental health. Part II. State of the parodontium.

A study of the oral health of workers in flour mills was carried out. The examined group consisted of 40 males and 8 females currently employed at flour mills. As much as 97.92 % of the workers showed evidence of parodontopathy. The results of the researches indicate the necessity of professional periodontal prophylaxis among mill workers.