Digital Image Correlation analysis on the bone displacement during split crest: An ex vivo study

The split crest is an established surgical technique for horizontal bone augmentation. It allows to place implants of adequate diameter in sites where the bone would be too thin for the implantation. In this study, two split crest techniques (using threaded bone expanders or ultrasonic bone surgery) were performed ex vivo on bovine ribs, and dental implants were then inserted in the so prepared implantation sites. Digital image correlation was used to measure the bone external surface displacement throughout the surgical procedures. Both techniques provided an adequate bone volume for implant insertion, and no significant differences were highlighted regarding the displacement. However, bone accidental fracture only occurred during split crest with threaded bone expanders, suggesting differences in the internal strain distribution induced by the two technique

In vitro simulation of dental implant bridges removal: Influence of luting agent and abutments geometry on retrievability

Implant fixed dental prostheses are widely used for the treatment of edentulism, often preferred over the screw-retained ones. However, one of the main features of an implant-supported prosthesis is retrievability, which could be necessary in the case of implant complications. In this study, the retrievability of implant-fixed dental prostheses was investigated considering two of the main factors dental practitioners have to deal with: the abutments geometry and the luting agent. Impulsive forces were applied to dental bridge models to simulate crowns’ retrievability in clinical conditions. The number of impulses and the impulsive force delivered during each test were recorded and used as retrievability indexes. One-hundred-and-five tests were conducted on 21 combinations of bridges and luting agents, and a Kruskal-Wallis test was performed on the results. The abutment geometry significantly influenced the number of impulses needed for retrieval (p < 0.05), and a cement-dependent trend was observed as well. On the other hand, the forces measured during tests showed no clear correlation with bridge retrievability. The best retrievability was obtained with long, slightly tapered abutments and a temporary luting agent

Biomolecular, histological, clinical, and radiological analyses of dental implant bone sites prepared using magnetic mallet technology: A pilot study in animals

Background. A new instrumentation exploiting magneto-dynamic technology (mallet) proposed for implant site preparation was investigated. Methods. In the tibias of three minipigs, two sites were prepared by mallet and two by drill technique. Primary stability (ISQ) was detected after implant positioning (T0) and at 14 days (T14). X-rays and computed tomography were performed. At T14, bone samples were utilized for histological and biomolecular analyses. Results. In mallet sites, histological evaluations evidenced a significant increase in the newly formed bone, osteoblast number, and a smaller quantity of fibrous tissue. These results agree with the significant BMP-4 augmentation and the positive trend in other osteogenic factors (biological and radiological investigations). Major, albeit IL-10-controlled, inflammation was present. For both techniques, at T14 a significant ISQ increase was evidenced, but no significant difference was observed at T0 and T14 between the mallet and drill techniques. In mallet sites, lateral bone condensation was observed on computed tomography. Conclusions. Using biological, histological, clinical, and radiological analyses, this study first shows that the mallet technique is effective for implant site preparation. Based on its ability to cause osseocondensation and improve newly formed bone, mallet technology should be chosen in all clinical cases of poor bone quality

In vitro impact testing to simulate implant-supported prosthesis retrievability in clinical practice: Influence of cement and abutment geometry

Cement-retained implant-supported prosthetics are gaining popularity compared to the alternative screw-retained type, a rise that serves to highlight the importance of retrievability. The aim of the present investigation is to determine the influence of luting agent, abutment height and taper angle on the retrievability of abutment-coping cementations. Abutments with different heights and tapers were screwed onto an implant and their cobalt-chrome copings were cemented on the abutments using three different luting agents. The removals were performed by means of Coronaflex®. The number of impulses and the forces were recorded and analyzed with a Kruskal-Wallis test. Harvard cement needed the highest number of impulses for retrieval, followed by Telio CS and Temp Bond. However, abutment height and taper showed a greater influence on the cap's retrievability (p < 0.05). Long and tapered abutments provided the highest percentage of good retrievability. The influence of the luting agent and the abutment geometry on the cap's retrieval performed by Coronaflex® reflects data from literature about the influence of the same factor on the maximum force reached during uniaxial tensile tests. The impulse force was slightly affected by the same factors

Sailing for Science: on board experiences for transferring knowledge on Historical Oceanography for Future Innovation

Smart, sustainable and inclusive Blue Growth means also knowing past technology and the paths followed by ancients in order to understand and monitor marine environments. In general, history of Science is a matter that is not enough explored and explained or promoted in high schools or university official programmes, and, usually, scientist do not consider it as an important part of their curricula. However, bad or good ideas, abandoned or forgotten beliefs, concepts, opinions, do still have a great potential for inspiring present and future scientists, no matter in which historical period they may have been formulated: they should be always be taken into consideration, critically examined and observed by a very close point of view, not just as part of the intellectual framework of some obsolete ‘Cabinet of Curiosities’ with limited access except for the chosen few. Moreover, history of Science should be transmitted in a more practical way, with hands-on labs showing the limits and challenges that prior generations of ocean explorers, investigators and seafarers had to face in order to answer to crucial questions as self-orientation in open sea, understanding main currents and waves, predicting meteorological conditions for a safe navigation. Oceanography is a relatively young branch of science, and still needs further approvals and knowledge (National Science Foundation, 2000). The Scientific Dissemination Group (SDG) “La Spezia Gulf of Science” – made up by Research Centres, Schools and Cultural associations located in La Spezia (Liguria, Italy) - has a decadal experience in initiatives aimed at people and groups of people of all ages, who are keen on science or who can be guided in any case to take an interest in scientific matters (Locritani et al., 2015). Amongst the SDG activities, the tight relationship with the Historical Oceanography Society, the Italian Navy and the Naval Technical Museum (that collects a rich heritage of civilization, technology and culture witnesses, related to the naval history of seamanship from the origins up to nowadays), allowed the creation of a special educational format based on Historical Oceanography, for university and high school students as an integration for their curriculum. The Historical Oceanography Society has provided the major knowledges included in the ancient volumes of its archive, thanks to the availability of its members that also held theoretical and practical lessons during the course. The present paper will describe the one-week special course (about 60 hours of theory and practice with technical visits to Research centres and Museums) that has been planned to be carried out on board of the Italian Training Navy Ship (A. Vespucci) and has been organized in order to give the hints about on board life, as well as theoretical lessons on modern and historical oceanography, hands-on labs on oceanographic instruments from public and private collections, physiology of diving techniques and astronomy. The general aim of this course has been, hence, to give to excellent students all those technological but also creative and imaginative features of our past.PublishedVienna1TM. Formazion

Small diameter and immediate loading implantology: A minimally invasive technique

OBJECTIVES Minimally invasive surgery is a new paradigma also in dentistry. Historically, implant-prosthetic rehabilitations included the use of normal diameter implants also in the anterior area, often associated with surgical procedures of bone regeneration, surgical procedures which often had a strong impact on the patient both from a psychological and temporal but above all surgical point of view. In fact, surgery was often very invasive and although using innovative methods and tools, the morbidity was high. An attempt was therefore made to use tools which were less traumatic as possible on the bone, such as piezoelectric instruments which, thanks to their overmodulated frequency, allowed a selective, micrometric cut and therefore guaranteed a surgery with a less traumatic impact because they gave the operator the possibility of having constant control of the surgical instrument. This fact guaranteed at the same time a better cutting effectiveness on the bone tissue without damaging the soft tissues. These prerogatives allowed to obtain a better healing of hard and soft tissues. Outcomes supported by scientific research that have demonstrated a better and faster biological response where a piezoelectric instrument was used to perform surgery. Unfortunately, however, the use of traditional diameter implants forced the operator to try to obtain significant bone regeneration to ensure sufficient bone thickness around the implants to avoid dangerous dehiscence not only for the aesthetic result but for the survival of the implants themselves, and therefore as a matter of fact the surgery proved to be equally invasive despite the use of piezoelectric instruments. At present, however, in various clinical situations, the use of reduced diameter implants (<3.5 mm) has been proposed to be able to minimize the surgical procedures of increase in bone volume thus guaranteeing the patient a reduction in treatment times and costs, as well as a minor surgical trauma, and if we add to this the use of a less traumatic instrument like the piezoelectric one we can understand how this combination can allow us to have less traumatic surgical approaches. During the past, every situation in which patient lost bone volumes was treated with guided bone regeneration. It determined longer and more expensive therapies. A valid alternative could be represented by narrow implants, to reduce treatment time and cost. It will be presented a case report in which the patient has been rehabilitated with a immediate loaded narrow implant in esthetic area (2.2), combining the use of a piezoelectric instrument that was perfectly operational thanks to the use of inserts suitable for the preparation of the correct size implant site to receive a 3 mm implant. Implants that over time, thanks also to scientific works, have demonstrated a high validity such as to allow operators to be able to resolve cases that traditionally would have been faced with surgery aimed at obtaining bone regeneration in order to place traditional- sized implants, in a much more simple and predictable way. In the end, the use of an aesthetic prosthetic product allows an optimal finalization of the clinical case. MATERIALS AND METHODS A young female patient with tooth 2.2 agenesia has been treated with a narrow implant due to inter-radicular proximity. It has been decided to use piezoelectric implant insertion and provisional immediate loading restoration. The case has been finished, after healing, with a litium disilicate definitive crown. DISCUSSION The evolution of surgical techniques seeks the reduction of post-operative morbidity and the reduction of the time and inconvenience of the intervention. Piezoelectric surgery has shown in particular a marked atraumaticity towards especially soft tissues and becomes an election choice in cases where surgical precision must be a primary objective. The small diameter implants allow to avoid very invasive regenerative procedures with long healing times. CONCLUSIONS Narrow implants could be considered a valid alternative to more invasive procedures like bone regeneration. CLINICAL SIGNIFICANCE The objective of the authors is to give to clinicians a valid therapeutic alternative, in every patient who need an implant supported rehabilitation but has poor bone volumes and less time or money capability

Cytokine, Chemokine, and Growth Factor Profile Characterization of Undifferentiated and Osteoinduced Human Adipose-Derived Stem Cells

Bone is the second most manipulated tissue after blood. Adipose-derived stem cells (ASCs) may become a convenient source of MSC for bone regenerative protocols. Surprisingly, little is known about the most significant biomolecules these cells produce and release after being osteoinduced. Therefore, the present study aimed at dosing 13 candidates chosen among the most representative cytokines, chemokines, and growth factors within the conditioned media of osteodifferentiated and undifferentiated ASCs. Two acknowledged osteoblastic cell models, that is, MG-63 and SaOs-2 cells, were compared. Notably, IL-6, IL-8, MCP-1, and VEGF were highly produced and detectable in ASCs. In addition, while IL-6 and IL-8 seemed to be significantly induced by the osteogenic medium, no such effect was seen for MCP-1 and VEGF. Overall SaOS-2 had a poor expression profile, which may be consistent with the more differentiated phenotype of SaOs-2 compared to ASCs and MG-63. Instead, in maintaining medium, MG-63 displayed a very rich production of IL-12, MCP-1, IP-10, and VEGF, which were significantly reduced in osteogenic conditions, with the only exception of MCP-1. The high expression of MCP-1 and VEGF, even after the osteogenic commitment, may support the usage of ASCs in bone regenerative protocols by recruiting both osteoblasts and osteoclasts of the host

Simulating super earth atmospheres in the laboratory

Several space missions, such as JWST, TESS and the very recently proposed ARIEL, or ground-based experiments, as SPHERE and GPI, have been proposed to measure the atmospheric transmission, reflection and emission spectra of extrasolar planets. The planet atmosphere characteristics and possible biosignatures will be inferred by studying planetary spectra in order to identify the emission/absorption lines/bands from atmospheric molecules such as water (H2O), carbon monoxide (CO), methane (CH4), ammonia (NH3), etc. In particular, it is important to know in detail the optical characteristics of gases in the typical physical conditions of the planetary atmospheres and how these characteristics could be affected by radiation driven photochemical and biochemical reaction. The main aim of the project 'Atmosphere in a Test Tube' is to provide insights on exoplanet atmosphere modification due to biological intervention. This can be achieved simulating planetary atmosphere at different pressure and temperature conditions under the effects of radiation sources, used as proxies of different bands of the stellar emission. We are tackling the characterization of extrasolar planet atmospheres by mean of innovative laboratory experiments described in this paper. The experiments are intended to reproduce the conditions on warm earths and super earths hosted by low-mass M dwarfs primaries with the aim to understand if a cyanobacteria population hosted on a Earth-like planet orbiting an M0 star is able to maintain its photosynthetic activity and produce traceable signatures