Characterization of a Macro- and Micro-Textured Titanium Grade 5 Alloy Surface Obtained by Etching Only without Sandblasting

Our purpose was to physically characterize the surface, and the subsurface, of a macro-and micro-textured titanium grade 5 dental implant surface obtained by etching only, without sandblasting. The topography, surface roughness, as well as the surface structure and subsurface distribution of elements, were determined by scanning electronic microscopy (SEM), non-contact profilometry, X-ray diffraction (XRD), and a concentration profile performed by Auger electron spectroscopy (AES). The hydrogen concentration in the implants was measured; the ability to generate nanostructures when stored in deionized water was also investigated. Under SEM, the surface resembled a sandblasted and etched titanium surface with its typical macro-and micro-texture; roughness was moderate with average roughness (Sa) 1.29 µm. No titanium hydride was found at the implant surface and no enrichment of any alloying element was identified at the surface and subsurface. Hydrogen concentration was 79 ppm, within the normative tolerance (<130 ppm). After storage in water for 6 months, densely packed finger-like nanostructures were observed. The clinical advantage of this textured titanium alloy surface is that it displays the typical macro-and micro-features of a moderately rough sandblasted and etched (SLA) titanium surface without leaving behind any foreign sandblasting material

In vitro Interactions between Streptococcus intermedius and Streptococcus salivarius K12 on a Titanium Cylindrical Surface

Peri-implantitis is a steadily rising disease and is caused by oral bacterial pathogens able to form biofilm on implant surfaces and peri-implant tissues, making antibiotics treatment less effective. The use of commercial probiotics against oral pathogens could serve as an alternative to prevent biofilm formation. Streptococcus intermedius is one of the early colonizers of biofilm formation in dental implants. The aim of this study was to model the interaction between S. intermedius and Streptococcus salivarius strain K12, a probiotic bacterium producing bacteriocins. S. intermedius was co-cultured with S. salivarius K12 in an in vitro model simulating the biofilm formation in a dental implant composed by a titanium cylinder system. Biofilm formation rate was assessed by Real-Time PCR quantification of bacterial count and expression levels of luxS gene, used in response to cell density in the biofilm. Biofilm formation, bacteriocin production, luxS expression patterns were found to be already expressed within the first 12 h. More importantly, S. salivarius K12 was able to counter the biofilm formation in a titanium cylinder under the tested condition. In conclusion, our dental implant model may be useful for exploring probiotic-pathogen interaction to find an alternative to antibiotics for peri-implantitis treatment

Periodontal microbiota of Sardinian children: comparing 200-year-old samples to present-day ones

Introduction: The microrganisms of the human oral cavity include more than 700 species or phenotypes of bacteria. Some “diseases of civilization” are strictly correlated to changes in the microbiome following the food revolution that occurred after WWII. For that reason, a precise recognition of the microbiome profile before and after this period should be useful to determine the health-compatible model of icrobiome. The aim of this study was to compare the microbiome profiles (number of total cells, and pathogen types) of dental samples obtained from two distinct groups of children, a 200-year-old retrieved one and a present one. Methods: Two different groups of samples have been studied. The first group was a set of 50 recent subgingival plaque samples obtained from children of age 2-8 years, 14 males and 36 females. They were enrolled by the Department of Dental Disease Prevention (University of Cagliari, in Sardinia, Italy) during standard dental care procedures. None reported periodontal disease and none had been under antibiotic therapy during the previous 6 months. The second group was an old retrieved group that included 24 teeth from 6 different 6- to 8-year-old crania fragments; they were obtained from a 200-year-old charnel-house located in Villaputzu, a city close to Cagliari. Representative periodontal bacteria have been identified by a previously published real-time PCR procedure (Sokransky et al., 1998) in which P. gingivalis and T. forsythia (red complex), A. Original article 2/5 www.jpnim.com Open Access Journal of Pediatric and Neonatal Individualized Medicine • vol. 6 • n. 1 • 2017 Orrù • Contu • Casula • Demontis • Blus • Szmukler-Moncler • Serreli • Maserati • Steri • Fanos • Coghe • Denotti actinomycetemcomitans (green complex) and F. nucleatum (orange complex) were detected. In addition, the title of each pathogen was expressed as a percentage of the total bacteria (biofilm) in the sample. Results and discussion: The profile of periodontal microbiomes, between recent/ancient samples showed a significant difference relative to Sokransky’s red complex bacteria (p < 0.05). In all analyzed periodontal strains, the pathogenic bacteria P. gingivalis and T. forsythia showed the highest title in the recent group. Conclusions: Our hypothesis is that the transfer of “commensal-pathogen” as an absolute number on the oral biofilm might be linked to the distinct alimentary habits of the two populations. Some diet rich in reducing agents, such as processed meat-based foods, might be able to increase the average number of pathogen anaerobic bacteria in the oral microbiota. The outcome would be an increase of the oral systemic diseases reported with these pathogens. Our data suggest that the ancient Sardinian population was able to control the pathogen oral anaerobic biofilm by some diet rich in antioxidant compounds. Further investigations are required to focus on the genetic profile and the health status of this ancient population but it appears that molecular microbiology might be considered as the “time machine” in oral biology

Placement of tapered implants using an osteotome sinus floor elevation technique without bone grafting: 1-year results

PURPOSE: Achieving implant primary stability in poor-density bone is difficult when the available bone height is less than 6 mm. This study assesses the 1-year clinical performance of tapered implants in sites of reduced height in combination with osteotome sinus floor elevation without bone grafting material. MATERIALS AND METHODS: An osteotome sinus floor elevation procedure without grafting material was performed in the atrophic posterior maxilla. Tapered implants were placed in maxillary sites with residual bone height of 1 to 6 mm. Implant primary stability was assessed by finger pressure exerted on the implant. Bone gain in the elevated sinus and crestal bone loss were evaluated at 1 year via radiographs. RESULTS: Fifty-four tapered implants were placed in 32 patients and were loaded after a mean of 4.2 +/- 1.6 months. The mean maxillary residual bone height was 3.8 +/- 1.2 mm. All implants achieved primary stability, and all were successfully loaded. At the 1-year radiographic control, the mean bone gain within the sinus was 2.5 +/- 1.7 mm and the mean crestal bone loss was 0.2 +/- 0.8 mm. CONCLUSIONS: In the atrophic posterior maxilla, primary stability can readily be achieved with tapered implants, even when the mean residual bone height is 3.8 mm. Despite limited bone support and lack of grafting material, all loaded implants were clinically stable, and crestal bone loss was limited. A net bone gain of 2.3 +/- 1.8 mm was observed. Survival and success rates were 100% and 94.4%, respectively. Elevation of the sinus membrane without the addition of bone grafting material led to bone formation beyond the original limit of the sinus floor

L’apport de l’ancrage squelettique en orthodontie

Pour assurer au mieux les mouvements orthodontiques, l’orthodontie a besoin de s’appuyer sur un ancrage fiable, le plus fixe possible. Dans de nombreux cas, l’ancrage intra-buccal ou même extra-buccal ne peut répondre aux exigences d’ancrage du praticien orthodontiste. En assurant un ancrage fixe, l’ancrage squelettique permet la mise en oeuvre de mouvements complexes tels que ingressions ou déplacements d’un groupe de dents. Cet article décrit l’ancrage squelettique, son développement historique, ses différentes applications, les paramètres à considérer, ses avantages puis ses limitations. Un cas clinique est présenté afin de montrer les différentes étapes du traitement ainsi que le résultat obtenu. Orthodontistes et impantologistes ont là une occasion de collaborer plus étroitement que par le passé. Cette interaction devrait permettre des traitements et des résultats considérés jusque-là comme impossibles à mener et à obtenir