Photogrammetric Analysis of Multiple Implant Abutment Impressions under Different Conditions

Purpose: The aim of this investigation was to evaluate and compare the dimensional accuracy of hydrophilic polysiloxane, vinyl polysiloxane (VPS), and polyether (PE) impression materials under dry, moist and wet conditions. Methods: An acrylic master model including 6 implants was formed, and 108 impressions were made up of this acrylic model at total. In this study, the materials of hydrophilic polysiloxane impression material, 1 hydrophilic vinyl polysiloxane impression material and 1 polyether impression material were tested. Twelve impression of each material were created under dry, moist and wet respectively. Two reference distances were evaluated on each study model by using a graphics-editing program whereas for comparison of mean dimensional changes one-way analysis of variance and Student t-test were used. Results: One-way analysis of variance revealed significant differences between impression materials and conditions (P P Conclusions: All impression materials showed a statistically significant difference under dry, moist and wet conditions.

Graphene oxide and mineralized collagen-functionalized dental implant abutment with effective soft tissue seal and romotely repeatable photodisinfection

Grasping the boundary of antibacterial function may be better for the sealing of soft tissue around dental implant abutment.Inspired by‘overdone is worse than undone’,we prepared a sandwich-structured dental implant coating on the percutaneous part using graphene oxide(GO)wrapped under mineralized collagen.Our unique coating structure ensured the high photothermal conversion capability and good photothermal stability of GO.The prepared coating not only achieved suitable inhibition on colonizing bacteria growth of Streptococcus sanguinis,Fusobacterium nucleatum and Porphyromonas gingivalis but also disrupted the wall/membrane permeability of free bacteria.Further enhancements on the antibacterial property were generally observed through the additional incorporation of dimethylaminododecyl methacrylate.Additionally,the coating with sandwich structure significantly enhanced the adhesion,cytoskeleton organization and proliferation of human gingival fibroblasts,which was effective to improve soft tissue sealing.Furthermore,cell viability was preserved when cells and bacteria were cultivated in the same environment by a coculture assay.This was attributed to the sandwich structure and mineralized collagen as the outmost layer,which would protect tissue cells from photothermal therapy and GO,as well as accelerate the recovery of cell activity.Overall,the coating design would provide a useful alternative method for dental implant abutment surface modification and functionalization.

The integration of peri-implant soft tissues around zirconia abutments:Challenges and strategies

Stable soft tissue integration around the implant abutment attenuates pathogen penetration,protects underlying bone tissue,prevents peri-implantitis and is essential in maintaining long-term implant stability.The desire for“metal free”and“aesthetic restoration”has favored zirconia over titanium abutments,especially for implant restorations in the anterior region and for patients with thin gingival biotype.Soft tissue attachment to the zirconia abutment surface remains a challenge.A comprehensive review of advances in zirconia surface treatment(micro-design)and structural design(macro-design)affecting soft tissue attachment is presented and strategies and research directions are discussed.Soft tissue models for abutment research are described.Guidelines for development of zirconia abutment surfaces that promote soft tissue integration and evidence-based references to inform clinical choice of abutment structure and postoperative maintenance are presented.