Objectives: The aim of the study was to evaluate in vitro the impact of bioengineered plant-derived Rhamnogalacturonan-I’s (RG-I) nanocoatings on osteogenic capacity and pro-inflammatory cytokine response of murine osteoblasts following Porphyromonas gingivalis (P. gingivalis) infection.Bioengineered RG-I’s from pectins are potential candidates for surface nanocoating of medical devices due to their physical, chemical, and biological properties. Methods: Murine osteoblast-like cells (MC3T3-E1) and isolated primary calvarial osteoblast from C57BL/6J (B6J osteoblasts) mice were infected with P. gingivalis and incubated on polystyrene tissue culture plates with or without nanocoatings of unmodified isolated RG-I's from potato pulps (PU) or dearabinanated RG-I's (PA). Cell proliferation, metabolic activity, mineralization and osteogenic and pro-inflammatory gene expression were examined at different time points and repeated six times each (n = 6). Results: Following P. gingivalis infection, MC3T3-E1 and B6J osteoblasts cell proliferation after 12, 24, 48 and 72 hours was significantly higher when cultured on PA but not PU coating as compared to cells cultured on control surface without nanocoating. Cell metabolic activity after 3, 7, 14 and 21 days was significantly enhanced in MC3T3-E1 and B6J osteoblasts cultures on surface coated with PA compared to control; on surface coated with PU in MC3T3 culture. Moreover, P. gingivalis infected MC3T3-E1 and B6J cells formed after 3, 7, 14 and 21 days significantly higher amount of calcium deposits on PA but not PU coating as compared to cells cultured on control surface. Finally, Il-1, Il-6, TNF-alpha and Rankl gene expression were down-regulated after 3, 7, 14 and 21 days in cells cultured on PU and to a higher extent on PA as compared to the corresponding control whereas Runx, Alpl, Col1a1, Bglap were up-regulated vice versa. Conclusion: Our data clearly show that pectin RG-I's nanocoating with high content of galactan (PA) reduces the osteoblastic response to P. gingivalis infection in vitro and may therefore reduce a risk of inflammation especially in immunocompromised patients with rheumatoid or periodontal disorders.

Outline: - Incision - Flap mobilization - Lateral sinus fenestration - Elevation of the Schneiderian membrane - Implant bed preparation - Bone chip harvesting at the mandibular angle - Filling of sinus lift lumen with autologous bone chips - Implant insertion - Covering the lateral sinus cavity with collagen membrane - Wound closure List of materials - Zeiss Pro Dent microscope with beam splitter and Panasonic 3 CCD camera - Scalpel holder (Ustomed) with Swann-Morton blades 15C and 12D - Narrow rasp (Hu-Friedy) - Micro-vacuum (Luer Lock Suction Tip, American Dental Systems) - Disposable vacuum tube set (Bexamed) - Disposable draping, Lindau (Aescologic) - Piezosurgery with diamond ball (Mectron) - Microforceps (Hu-Friedy) - Excavator (Martin) - Periodontometer, 1-mm gradation (Hu-Friedy) - OsseoSpeed implant set, Dentsply Implants: Marking drill; Twist drill, 2 mm; Depth gauge; Pilot drill, 2/3.2 mm; Twist drill, 3.2 mm; Tapered drill, 3.2/5 mm; OsseoSpeed TX implant, 5.0 × 11 mm; Closure screw, 4.5/5 mm - Columbia curette (Ustomed) - Micross scraper (Meta) - Needle holder (Ustomed) - Langenbeck wound retractor (Ustomed) - Kelly scissors (Ustomed) - Buchanan endodontic hand plugger (American Dental Systems) - Resorbable collagen membrane (Resodont, Resorba) - Ethilon 5-0 FS-3 (Ethicon) - Prolene 6-0 DA-2 (Ethicon)

Objectives: To examine histologically the characteristics of the residual material obtained during the placement of dental implants in sites where bone regeneration was previously performed by the procedure of maxillary lateral sinus floor lift, comparing the histological characteristics when a xenograft alone (Geitslich Bio-Oss®) was used versus regenerations where a combination of xenograft and allograft (Bio-Oss®+Puros®) was used. Methods: A descriptive cross-sectional study was conducted according to the established rules of research on human subjects and adjusted to the scientific, technical and administrative standards, with the support of the Research and Ethics Committee of the Faculty of Dentistry at the Pontifical Universidad Javeriana (CIEFOUJ). Analysis of 11 cores obtained from sites that were regenerated by a lateral approach for the elevation of the maxillary sinus floor, 4 cores in control group where a xenograft alone (Geitslich Bio-Oss®) was used and 7 cores in group test (Bio-Oss® + Zimmer Puros®), the samples were obtained from 6 to 12 months after the elevation of the maxillary sinus floor. Histological analysis was performed by an expert pathologist who made observations of the core samples using hematoxylin and eosin staining and polarized light to differentiate structure characteristics, further quantitative analysis was conducted with a public domain Java image processing program (imagej) and an statistical analysis was applied with a Wilcoxon (Mann-Whitney) test. Results: After the samples were processed and analyzed, histologically both groups showed graft particles surrounded by new bone, osteoid cells and osteoblasts. There was graft material in intimate contact with new bone and bone apposition lines with active zones. The control group consistently showed a greater presence of mature cortical new formed bone in comparison to the test group, where the observation showed a more disorganized structure with areas of new formed cancellar bone with areas of cortical bone. The quantitative analysis showed an average of 34% of new bone in control group (xenograft) and 27% in the test group (allograft + xenograft), however the statistical test showed a p value= 0.25. Conclusion: The initial argument of the present study was to analyze histologically the behavior and results of sites regenerated by an effective technique and using clinically proven bone substitutes; and comparing the combination (xenograft + allograft) with the novelty that xenograft alone was used as a control group, being that this design was not reported in common scientific databases at the moment that the study was initiated. Both control and test group resulted in bone resorption and new bone formation, there was not a statistically significant difference between the use of xenograft as a single material or in combination with allograft for maxillary sinus floor lift and subsequent placement of dental implants, also there were no differences in primary stability at the time of placement of the implants. However, the sample size calls for further investigations in order to increase the evidence of the comparison proposed in the present study.