Perioral aerosol sequestration suction device effectively reduces biological cross-contamination in dental procedures

Background: The infection risk during dental procedures is a common concern for dental professionals which has increased due to coronavirus (SARS-CoV-2) pandemic. The development of devices to specifically mitigate cross-contamination by droplet/splatter is crucial to stop infection transmission. This study assesses the effectiveness of a perioral suction device (Oral BioFilter, OBF®) to reduce biological contamination spread during dental procedures. Methods: Forty patients were randomized 1:1 to standard professional dental hygiene treatment with OBF® or not. Adenosine Triphosphate (ATP) bioluminiscence assay was used to evaluate the spread of potential contaminants. The total number of Relative Light Units (RLU) from key dental operatory locations: operator's face-shield, back of the surgical operator's-gloves, patient's safety-goggles, and instrumental table, were measured. Percentage contamination reductions between control and OBF® were compared. Results: For the whole dental environment, the RLUs reduction (300) being 100% on the surfaces closer to the patient's mouth and decreasing to 70% on instrumental table. In contrast, the higher failure percentage in the OBF®-group was found on the patient's googles (40%), while the operator face-shield showed an absence of contamination. Conclusion: OBF® device has shown efficacy to reduce biological droplet/splatter cross-contamination using ATP-bioluminiscence assay during dental procedures. Nevertheless, for maximum safety, its use must be combined with standard protective gear such as goggles, face shield and surgical glove

An anatomical study of nerves at risk during minimally invasive hallux valgus surgery

The growing popularity of minimally invasive surgical (MIS) procedures makes it necessary that new anatomical references arise, to aid in tridimensional orientation and localization of structures that are not directly visible to the surgeon. This is especially critical for structures at risk like nerves or blood vessels. Optimization of the handling of cadaveric material and the combination of multiple techniques compensate for the limited availability of adequate specimens. The described protocol combines anatomical plane-by-plane dissection and sectional anatomy of fresh-frozen specimens to help localize relevant structures, such as nerves, arteries, veins and to correctly position the portals during MIS procedures. Depiction of these structures in anatomy textbooks can differ from what is encountered in the surgical field; and for this reason, new anatomical studies with a surgical orientation are needed. However, this is a complex, time-consuming technique requiring specific training. The anatomical references described with the so-called 'clock method' provide the surgeon with an easy and reproducible system to locate the path of the nerves at risk in Hallux Valgus MIS procedures. This model can be extrapolated to many other minimally invasive surgical procedures

Body donation, teaching and research in dissection rooms in Spain in times of Covid-19

The state of alarm due to Covid-19 pandemic in Spain stopped all educational and most university research activities. The Spanish Anatomical Society (SAE) Consensus Expert Group on Body Donations piloted a study based on a questionnaire to know the status of body donations and dissection activities during the lockdown, as well as the future implications of Covid-19 pandemic for body donation programs and Anatomy teaching. The questionnaire results show that Spanish Universities refused body donations and stopped all dissection research and teaching. The Covid-19 expected influence on Anatomy teaching was referred to the increase of teaching workforce and resources required to apply the new safety measures to future practical activities, as well as to prepare and adapt teaching material for online-only programs. The application of reinforced safety measures was expected to be perceived by the respondent's students as a gain in teaching quality, while the transformation of the anatomy courses in online-only programs will be perceived as a quality decrease. The respondent's concerns about future institutional implications of the pandemic were related to increased costs of the adaptation of the facilities and the reinforced preventive measures, as well as the eventual decrease in donations. The complete lockdown applied on dissection rooms is not justified by scientific evidence and represents a break of the confidence deposed in the institutions by the donors. A consensus is required for the adoption of a renewed, comprehensive protocol for present and future body donations including the evidence Covid-19 pandemic has contributed to create

Repercusiones clínicas de la anorexia nerviosa restrictiva en la cavidad oral

¿Cuáles son los signos de alerta que aparecen en la cavidad oral de los pacientes con trastornos de la conducta alimentaria? Factores biológicos como la edad, el sexo, el balance hormonal o la osteoporosis, aparte de factores propios de la cavidad oral, se han considerado como significativos en la progresiva reducción del tejido duro del proceso alveolar en las mandíbulas edéntulas. En concreto, se ha descrito una correlación estadísticamente significativa entre la variación de la densidad mineral de la mandíbula y la del radio de ambos sexos y que, a pesar de la variación en la morfología entre la mandíbula y los huesos largos, se observa que los cambios se producen con la edad, y que estos cambios afectan cualitativamente a las dos partes del esqueleto de la misma manera

Morfología de los conductos radiculares de premolares superiores e inferiores

El propósito de este estudio fue caracterizar la anatomía de los conductos radiculares de dientes premolares superiores e inferiores provenientes de pacientes españoles. Fueron seleccionados 200 dientes premolares permanentes sometidos a diafanización. Para el estudio de los conductos radiculares se empleó la clasificación de Vertucci. La incidencia de conducto tipo I (un conducto) para los primeros premolares superiores fue de 5.88%, mientras que un 88.22% presentó dos conductos (de tipo II a tipo VI). Sólo el 5.88% de los primeros premolares superiores fueron tipo VIII (tres conductos). En los segundos premolares superiores, la incidencia de un conducto (tipo I) fue de 39.65%, y el 60.31% presentaron dos conductos (de tipo II a tipo VII). La incidencia de un conducto (tipo I) fue de 68.18% para los primeros premolares inferiores, y un 31.8% presentó dos conductos (de tipo II a tipo V). En los segundos premolares inferiores, la incidencia de tipo I (un conducto) fue de 73.91%, mientras que el 26.08% presentó dos conductos (de tipo IV a V). Salvo en el caso del segundo premolar inferior, nuestros resultados coincidieron con los de trabajos previos hechos en otras poblaciones

A Regenerative Endodontic Approach in Mature Ferret Teeth Using Rodent Preameloblast-conditioned Medium

Background: This study evaluated the effectiveness of a regenerative endodontic approach to regenerate the pulp tissue in mature teeth of ferret. The presence of odontoblast-like cells in the newly-formed tissue of teeth treated with or without preameloblast-conditioned medium was evaluated based on morphological criteria. Materials and methods: Twenty-four canines from six ferrets were treated. The pulp was removed, and the apical foramen was enlarged. After inducing the formation of a blood clot, a collagen sponge with or without preameloblast-conditioned medium was placed underneath the cementoenamel junction. The samples were analyzed at the eighth week of follow-up. Results: Vascularized connective tissue was observed in 50% of teeth, without differences between groups. The tissue occupied the apical third of the root canals. Odontoblast-like cells were not observed in any group. Conclusion: Revitalization of mature teeth is possible, at least in the apical third of the root canal. Further experimental research is needed to produce more reliable outcomes

Immediate small-diameter implants as abutments for an overdenture in the edentulous atrophic mandible: report of immersion endoscopic bone in vivo, and histologic bone-implant evaluation after 6 months of function

The aim of this report was to endoscopically evaluate bone quality in vivo in the immediate installation of temporary small-diameter implants, and again after 6 months of function, through an attachments system for overdenture, in the atrophic mandible of a patient. We also histologically evaluated bone-implant interaction in these temporary small-diameter implants, once the success of the osseointegration of the submerged implants was guaranteed. A patient received a total of 6 implants in the atrophic mandible, two of which were immediately loaded with a provisional prosthesis, and four were left to heal in a submerged way. Further, an immersion endoscopic evaluation was performed during bone drilling, and this showed a compact bone structure with limited vascularization and predominantly cortical structure.This immediate loading protocol involving an overdenture retained by two small-diameter implants of 2.9 mm in the atrophic mandible proved to be successful after 6 months of loading. Clinical and histologic osseointegration was consistently achieved for both of the retrieved immediately loaded implants. This modality allows the patient to be restored with a stable, functional, and aesthetic prosthesis during the osseointegration period of submerged implants and soft-tissue healing, before the removal of the provisional implants. The histological evaluation of bone-implant contact found that the space between the implant threads closer to the surface was filled with woven bone and lamellar bone, but the tissue in contact with the cervical portion of the implants was compatible with cortical bone organization. Also, the newly formed bone has a regular cell distribution and characteristics of advanced maturation after 6 months of function in the atrophic mandible. Anchored overdentures in 2 to 4 small-diameter implants (2.9 mm) for edentulous patients with severe atrophy of the mandible with cortical bone would be a minimally invasive alternative

Effect of drill speed on the strain distribution during drilling of bovine and human bones

Drilling is an operation commonly required in orthopaedic surgery for insertion of screws and internal fixation of bone fractures. Induced damage is one of the undesired effects of drilling mainly due to the use of inadequate drilling parameters. During the recent years, scientists have been trying to describe the relationship between drilling parameters and bone injury. However, no studies have examined the level of strain generated in the bone during the drilling process. This paper focuses on the analysis of different drill speeds during drilling of fresh bovine femora and human cadaveric tibiae. The main contribution of this work is to determine how differences in applied drill speeds affect the strain of cortical tissue near the drilling site and the drill bit temperature. Strains were measured in ex-vivo material during the osteotomy preparation with three drill speeds (520, 900 and 1370 r.p.m.). Additionally, a thermographic camera was used to measure the drill bit temperature. As the drilling operations are blind in nature with unknown depth, the osteotomies were performed using a drill press machine without control of the feed rate or depth. Drill bit geometry was kept constant with 4 mm of diameter, point angle 120⁰ and helix angle 30⁰. The tests were conducted at room temperature without applying cooling at the drilling zone. Bone strains near to the drilling sites were recorded with high accuracy using linear strain gages mounted around the diaphyseal cortex. It was noted that the bone strain and drill bit temperature increased with an increasing drill speed. Human and bovine bone samples presented significantly different levels of strain and temperature. Both strain and temperature were higher when drilling bovine femora than when drilling human cadaveric tibiae

Biofunctionalization with a TGF -1 inhibitor peptide in the osseointegration of synthetic bone grafts: an in vivo study in Beagle dogs

Objectives: The aim of this research was to determine the osseointegration of two presentations of biphasic calcium phosphate (BCP) biomaterial¿one untreated and another submitted to biofunctionalization with a TGF- 1 inhibitor peptide, P144, on dental alveolus. Materials and Methods: A synthetic bone graft was used, namely, (i) Maxresorb® (Botiss Klockner) (n = 12), and (ii) Maxresorb® (Botiss Klockner) biofunctionalized with P144 peptide (n = 12). Both bone grafts were implanted in the two hemimandibles of six beagle dogs in the same surgical time, immediately after tooth extraction. Two dogs were sacrificed 2, 4, and 8 weeks post implant insertion, respectively. The samples were submitted to histomorphometrical and histological analyses. For each sample, we quantified the new bone growth and the new bone formed around the biomaterial's granules. After optical microscopic histological evaluation, selected samples were studied using backscattered scanning electron microscopy (BS-SEM). Results: The biofunctionalization of the biomaterial's granules maintains a stable membranous bone formation throughout the experiment timeline, benefitting from the constant presence of vascular structures in the alveolar space, in a more active manner that in the control samples. Better results in the experimental groups were proven both by quantitative and qualitative analysis. Conclusions: Synthetic bone graft biofunctionalization results in slightly better quantitative parameters of the implant's osseointegration. The qualitative histological and ultramicroscopic analysis shows that biofunctionalization may shorten the healing period of dental biomaterials

Increasing the safety of minimally invasive hallux surgery: an anatomical study introducing the clock method

Background: the purpose of this study is to describe a simple and reproducible method to localize the neurological structures at risk and to describe a safe zone for hallux minimally invasive surgery (MIS) procedures. Methods: ten fresh-frozen cadaveric feet were dissected to identify the dorsomedial digital nerve (DMDN) and the dorsolateral digital nerve (DLDN) of the first toe. Axial sections were performed at the sites of metatarsal osteotomies. We documented the position of the nerves with respect to the extensor hallucis longus (EHL) tendon using a clock method superimposed on the axial section. Results: the DMDN was found at an average of 26.2° medial to the medial border of the EHL tendon. (SD 11.26, range 14.5-45.5), whereas the average distance of the DLDN was 32.3° lateral to the medial border of the EHL tendon. (SD 6.29, range 13.5-40). Conclusions: using the clock method the DMDN and DLDN were found consistently between 10 o'clock and 2 o'clock in either right and left feet. The clock method may facilitate avoiding the area where these nerves are located serving as a valuable tool in minimally invasive foot surgery