[Effect of dragon's blood extract on periodontal tissue repair and TLR4/NF-κB signal pathway].

Purpose: To discuss the effects of dragon's blood extract, a Chinese herb, on periodontal tissue repair and toll like receptor 4/nuclear transcription factor kappa B(TLR4/NF-κB) in gingivitis rats.

Methods: Sixty rats were randomly divided into control group, gingivitis group and low, medium and high dose groups of dragon's blood extract, with 10 rats in each group. Except the control group, the gingivitis rat model was established by silk thread ligation in other groups.

[Evaluation of the effect of Insignia system in customized orthodontic treatment].

Porpose: To investigate the effect of Insignia system in customized orthodontic treatment.

Methods: A total of 71 patients with malocclusion undergoing orthodontic treatment in Dalian Stomatological Hospital from March 2018 to August 2019 were enrolled, and divided into two groups according to random number table methods. Patients in non-customized group received Damon Q self-locking brackets, while patients in customized group received individualized brackets combined with Insignia appliance.

[Comparison of shaping ability of 4 nickel-titanium rotary instruments in preparation of curved root canals].

Prupose: To compare the shaping ability of 4 nickel-titanium rotary instruments in preparation of curved root canals.

Methods: Forty extracted human maxillary first or second molars with mesiobuccal root canal curvature ranging from 20°-40° were selected. The teeth were randomly equally divided into 4 groups(n=10).

[Investigation of the micromorphological differences of the implant-abutment junction].

Purpose: The aim of this pilot study was to investigate the morphological micro-features of 3 commercially available implant-abutment joints, using compatible and original prosthetic components and to explore the correlation between the micromorphology and potential functional complications.

Methods: Three abutments (one original and two compatibles) were torqued on original Straumann RN implants, according to the manufacturer's instructions. The implant-abutment units were sliced in the microtome and photographed under different magnifications through a scanning electron microscope.