Study of the Milkability of the Mediterranean Italian Buffalo and the Tunisian Maghrebi Camel According to Parity and Lactation Stage.

While considered as hard milkers, both buffaloes and camels are milked with equipment destined for dairy cows based on external morphological similarities with this species. This work aimed to study similarities and differences in milkability traits between Mediterranean buffaloes and Maghrebi she-camels and to evaluate the effect of parity and lactation stage. A total of 422 milk flow curves recorded with an electronic milkmeter (Lactocorder®) for both species were accessed. Milking characteristics including milk yield per milking, peak milk flow, average milk flow, duration of the main milking phase, duration of total milking, duration of various phases of milk flow, lag time and time to milk ejection, stripping yield, overmilking time and incidence of bimodal milk flow curves were evaluated for both species. Results showed that the values of milk yield per milking, duration of the main milking phase and duration of total milking were higher in buffaloes (3.98 ± 0.10 kg; 4.07 ± 0.11 min; 9.89 ± 0.21 min, respectively) compared to camels (3.51 ± 0.08 kg; 3.05 ± 0.09 min; 3.76 ± 0.09 min, respectively). However, camels had significantly higher peak and average milk flow (2.45 ± 0.07 kg/min and 1.16 ± 0.03 kg/min, respectively). Camels took significantly less time for milk ejection to occur. Only 15.49% of recorded curves were bimodal in buffaloes while 34.93% of bimodal curves were recorded for camels. Overmilking was significantly higher in buffaloes (3.64 ± 0.21 min vs. 0.29 ± 0.02 min). Parity and lactation stage had a significant effect on most studied milking traits suggesting the need for some particular practices with primiparous animals and animals at different levels of lactation for both species.

Robotic monitoring of dunes: a dataset from the EU habitats 2110 and 2120 in Sardinia (Italy).

This data descriptor presents a novel dataset collected using the quadrupedal robot ANYmal C in the Mediterranean coastal dune environment of the European Union (EU) habitats 2110 and 2120 in Sardinia, Italy. The dataset mainly consists of photos, videos, and point clouds of the coastal dunes, providing valuable information on the structure and composition of this habitat. The data was collected by a team of robotic engineers and plant scientists as result of a joint effort towards robotic habitat monitoring. The dataset is publicly available through Zenodo and can be used by researchers working in both the fields of robotics and habitat ecology and conservation. The availability of this dataset has the potential to inform future research and conservation efforts in the EU habitats 2110 and 2120, and it highlights the importance of interdisciplinary collaboration in the field of habitat monitoring. This paper serves as a comprehensive description of the dataset and the methods used to collect it, making it a valuable resource for the scientific community.

Advancements in combining electronic animal identification and augmented reality technologies in digital livestock farming.

Modern livestock farm technologies allow operators to have access to a multitude of data thanks to the high number of mobile and fixed sensors available on both the livestock farming machinery and the animals. These data can be consulted via PC, tablet, and smartphone, which must be handheld by the operators, leading to an increase in the time needed for on-field activities. In this scenario, the use of augmented reality smart glasses could allow the visualization of data directly in the field, providing for a hands-free environment for the operator to work. Nevertheless, to visualize specific animal information, a connection between the augmented reality smart glasses and electronic animal identification is needed. Therefore, the main objective of this study was to develop and test a wearable framework, called SmartGlove that is able to link RFID animal tags and augmented reality smart glasses via a Bluetooth connection, allowing the visualization of specific animal data directly in the field. Moreover, another objective of the study was to compare different levels of augmented reality technologies (assisted reality vs. mixed reality) to assess the most suitable solution for livestock management scenarios. For this reason, the developed framework and the related augmented reality smart glasses applications were tested in the laboratory and in the field. Furthermore, the stakeholders' point of view was analyzed using two standard questionnaires, the NASA-Task Load Index and the IBM-Post Study System Usability Questionnaire. The outcomes of the laboratory tests underlined promising results regarding the operating performances of the developed framework, showing no significant differences if compared to a commercial RFID reader. During the on-field trial, all the tested systems were capable of performing the task in a short time frame. Furthermore, the operators underlined the advantages of using the SmartGlove system coupled with the augmented reality smart glasses for the direct on-field visualization of animal data.

Assessment of video see-through smart glasses for augmented reality to support technicians during milking machine maintenance.

Smart glasses for augmented reality are digital technology under investigation in the agricultural sector. The potential of augmented reality was underlined, in some scientific contributions, as a support tool for farmers' activities and for the decision-making process. One of the most practical applications studied for augmented reality was in maintenance operations, where the use of smart glasses showed high capability. This work focuses on the evaluation of the performance and applicability of smart glasses with a video see-through display system and testing the device's available functions in agricultural frameworks. In addition, an augmented assistance scenario describing the main steps involved in the functioning of the maintenance operation was developed for milking machine inspection. The audio-video quality, battery life, detection capabilities of markers, and voice control interaction system were evaluated. The results showed the capabilities of smart glasses to reach augmented information from a long distance in a short time interval and to transmit audio and video with a high level of detail, allowing discrimination of small objects during remote assistance with reduced delay. The built maintenance scenario represents an example of augmented reality digital assistance application in the inspection and maintenance of the milking machine. The device performance and the proposed maintenance scenario underline the potential that augmented reality could have in the agricultural sector to assist and guide both farmers and technicians to timely problem solving. This solution fits into the agriculture 4.0 perspective, which is increasingly focused on digital transformation to improve farms' efficiency and sustainability.

Influence of milking units and working vacuum level on the mechanical milking of goats.

The objectives of this study were to evaluate and compare the effect of working vacuum levels (35 and 44 kPa) and liners dimensions (mouthpiece lip diameter and overall length, 20-185 and 22-170 mm) on the main milking characteristics of goats. The results highlight that both the working vacuum level and the liner dimension have influenced the milk flow curve parameters. The maximum variations were found for peak flow rate, which increased significantly with liner dimensions of 20-185 mm at a working vacuum level of 44 kPa as well as average milk flow rate and for plateau phase duration. The incorrect adoption of operative parameters and unsuitable milking machine components, might affect the performance of the mechanical milking and negatively affecting animal productions and welfare.

Advances in Unmanned Aerial System Remote Sensing for Precision Viticulture.

New technologies for management, monitoring, and control of spatio-temporal crop variability in precision viticulture scenarios are numerous. Remote sensing relies on sensors able to provide useful data for the improvement of management efficiency and the optimization of inputs. unmanned aerial systems (UASs) are the newest and most versatile tools, characterized by high precision and accuracy, flexibility, and low operating costs. The work aims at providing a complete overview of the application of UASs in precision viticulture, focusing on the different application purposes, the applied equipment, the potential of technologies combined with UASs for identifying vineyards' variability. The review discusses the potential of UASs in viticulture by distinguishing five areas of application: rows segmentation and crop features detection techniques; vineyard variability monitoring; estimation of row area and volume; disease detection; vigor and prescription maps creation. Technological innovation and low purchase costs make UASs the core tools for decision support in the customary use by winegrowers. The ability of the systems to respond to the current demands for the acquisition of digital technologies in agricultural fields makes UASs a candidate to play an increasingly important role in future scenarios of viticulture application.

Opioid overdose risk during and after drug treatment for heroin dependence: An incidence density case-control study nested in the VEdeTTE cohort.

INTRODUCTION AND AIMS: To corroborate protective effects of a range of drug treatment modalities against overdose mortality risk. DESIGN AND METHODS: Nested case-control study, with incidence density sampling, selecting controls retrospectively at each case event. Cases and controls came from a sub-cohort of opioid-dependent patients (n = 4444) from two Italian regions (Lazio and Piedmont). From 1998 to 2005, there were 91 overdose deaths (cases) matched to 352 controls. The primary outcome was overdose mortality and the primary exposure was drug treatment: opioid agonist treatment (OAT), opioid detoxification, residential community, psychosocial and other pharmacological treatment. Conditional logistic regression models generated intervention effects comparing mortality risk in and out of treatment, adjusting for confounding variables. RESULTS: Overall, drug treatment reduced overdose mortality risk by 80% [adjusted odds ratio (AOR) 0.18, 95% confidence interval (CI) 0.10-0.33, P < 0.001] compared to being out of treatment. There was a particularly strong protective effect of OAT on overdose mortality (AOR 0.08, 95% CI 0.03-0.23, P < 0.001) compared to being out of treatment. There was evidence of a substantially elevated risk of overdose in the first month of leaving treatment (AOR 23.50, 95% CI 7.84-70.19, P < 0.001) compared to being in treatment. DISCUSSION AND CONCLUSIONS: The nested case-control design strengthened earlier findings that OAT in Italy has strong protective effects on overdose mortality risk, much stronger than has been previously seen in other Western European settings.

Influence of the Milking Units on the Pulsation Curve in Dairy Sheep Milking.

Mechanical milking is a critical operation in ewe dairy farming where the operative parameters and the milking routine strongly influence milk production and animal welfare. The challenge in adapting dairy animals to the farm environmental conditions may cause illness and compromise the quality of the products. From this perspective, it is important to evaluate the technological and operational aspects that can influence milk quality and animal welfare. Thus, the aim of this work was to investigate the effects on the pulsation curve of several teat cup characteristics (volume of the pulsation chamber) at determined operating parameters (vacuum level and pulsator rate) recorded from nine different milking units. Moreover, the touch point pressure of different liners was measured. Data analysis showed that the sheep milking unit characteristics affected the pulsation curve significantly. The length of both the increasing vacuum phase and the decreasing vacuum phase (phase "a" and "c", respectively), which affect the milking and massage phases, was directly related to the pulsation chamber volume (R2 = 0.86) and the pulsator rate. No relationship emerged between the touch point pressure and specific characteristics of the liners such as the material, the shape, the diameter, the length, or the extension of the body. Considering the delicate role that the pulsation plays in ensuring animal welfare during milking, it is important to take into account the complete configuration and operative characteristics of the milking units. This will ensure that the complex interaction between the pulsation system and the milking units is considered when planning and assembling milking systems.

Exploring Smart Glasses for Augmented Reality: A Valuable and Integrative Tool in Precision Livestock Farming.

The growing interest in Augmented Reality (AR) systems is becoming increasingly evident in all production sectors. However, to the authors' knowledge, a literature gap has been found with regard to the application of smart glasses for AR in the agriculture and livestock sector. In fact, this technology allows farmers to manage animal husbandry in line with precision agriculture principles. The aim of this study was to evaluate the performances of an AR head-wearable device as a valuable and integrative tool in precision livestock farming. In this study, the GlassUp F4 Smart Glasses (F4SG) for AR were explored. Laboratory and farm tests were performed to evaluate the implementation of this new technology in livestock farms. The results highlighted several advantages of F4SG applications in farm activities. The clear and fast readability of the information related to a single issue, combined with the large number of readings that SG performed, allowed F4SG adoption even in large farms. In addition, the 7 h of battery life and the good quality of audio-video features highlighted their valuable attitude in remote assistance, supporting farmers on the field. Nevertheless, other studies are required to provide more findings for future development of software applications specifically designed for agricultural purposes.

Vibration and Noise Transmitted by Agricultural Backpack Powered Machines Critically Examined Using the Current Standards.

European Directives 2002/44/EC and 2003/10/EC establish the exposure limit values for preventing operators' risks to vibration and noise transmitted by machines. Few studies studied noise and vibration of agricultural backpack powered machines (as mist blowers and blowers), but nobody critically studied them. This work analyzed the field back vibration, hand-arm vibration (HAV), and noise transmitted to ten operators by eight blowers and mist blowers. Unweighted and weighted vibration were analyzed, using the standards ISO 2631-1 (back), and ISO 5349-1 and ISO/TR 18570 (hand-arm system). The noise was evaluated by recording the acoustic pressure level at the operators' ears using the ISO 9612. With the ISO 2631-1, the vibration to the operators' back was low (0.38 ms-2), but the unweighted vibration measured along y and z-axes (not used by the ISO 2631-1) were high (>11 ms-2). HAV were also low when using the ISO 5349-1 (the highest value was 2.51 ms-2 in mist blowers), but high with the ISO/TR 18570 for the onset of vibration white finger (1446 ms-1.5 in blowers). Noise levels were always high: more than 100 dB(A), excluding the blower with the exhaust inside the blower hose. This last machine had noise levels lower than 86 dB(A), but its specific feature could increase environmental pollution.

Dispersal mode and spatial extent influence distance-decay patterns in pond metacommunities.

Assuming that dispersal modes or abilities can explain the different responses of organisms to geographic or environmental distances, the distance-decay relationship is a useful tool to evaluate the relative role of local environmental structuring versus regional control in community composition. Based on continuing the current theoretical framework on metacommunity dynamics and based on the predictive effect of distance on community similarity, we proposed a new framework that includes the effect of spatial extent. In addition, we tested the validity of our proposal by studying the community similarity among three biotic groups with different dispersal modes (macrofaunal active and passive dispersers and plants) from two pond networks, where one network had a small spatial extent, and the other network had an extent that was 4 times larger. Both pond networks have similar environmental variability. Overall, we found that environmental distance had larger effects than geographical distances in both pond networks. Moreover, our results suggested that species sorting is the main type of metacommunity dynamics shaping all biotic groups when the spatial extent is larger. In contrast, when the spatial extent is smaller, the observed distance-decay patterns suggested that different biotic groups were mainly governed by different metacommunity dynamics. While the distance-decay patterns of active dispersers better fit the trend that was expected when mass effects govern a metacommunity, passive dispersers showed a pattern that was expected when species sorting prevails. Finally, in the case of plants, it is difficult to associate their distance-decay patterns with one type of metacommunity dynamics.

[Paclitaxel-coated balloons for in-stent restenosis treatment: long-term clinical results and predictors of recurrent target lesion revascularization]. / Palloncini medicati a eluizione di paclitaxel nel trattamento delle ristenosi intrastent: risultati clinici a lungo termine e predittori di nuova rivascolarizzazione della lesione bersaglio.

BACKGROUND: The aim of this study was to report clinical outcomes in patients treated with paclitaxel-coated balloons (PCB) for in-stent restenosis (ISR) in both bare metal (BMS) and drug-eluting stent (DES). METHODS: Between May 2009 and December 2015, we treated 155 ISR in 140 patients. At recruitment, 35% of patients had diabetes. Among the lesions, 125 were first occurrence (55 within BMS and 70 within DES) and 30 recurrent; 24 ISR were multi-metal layered. Mean reference diameter was 2.79 ± 0.52 mm and mean lesion length 13.2 ± 7.1 mm. PCB use included 32 Dior I, 97 InPact Falcon, 18 Panthera Lux, and 8 Restore DEB. RESULTS: At a median follow-up of 442 days, we observed 18 target lesion revascularizations (TLR), one myocardial infarction, 3 cardiac deaths, and 5 non-cardiac deaths. TLR occurrence differed according to type of ISR (4% within BMS, 14% within DES, 28% within recurrent ISR; p<0.05). TLR was associated with PCB type (35% Dior I, 9% InPact Falcon, 0% Panthera Lux and Restore DEB; p<0.05). Multivariable analysis revealed that first-generation PCB without a carrier (hazard ratio [HR] 2.50, 95% confidence interval [CI] 0.96-6.50; p=0.06) and recurrent ISR (HR 7.76, 95% CI 1.56-38.66; p=0.01) correlated with subsequent TLR. CONCLUSIONS: Our results confirm the safety and efficacy of PCB for ISR treatment both within BMS and DES. PCB type and recurrent ISR correlate with subsequent TLR.

Periodontal health in teenagers treated with removable aligners and fixed orthodontic appliances.

OBJECTIVES: The purpose of this study was to explore the microbiological and periodontal changes occurring in adolescents during 12 months of orthodontic therapy with removable aligners and with fixed appliances. MATERIAL AND METHODS: During the years 2012-2013, 50 teenagers aged 10-18 years with similar initial orthodontic conditions participated in this trial in a university clinic in northern Italy. After receiving professional oral hygiene and instructions on a standardized oral hygiene protocol, the adolescents were randomly assigned to either orthodontic treatment with traditional fixed brackets (n = 25) or to treatment with Invisalign® aligners (n = 25). Subgingival microbiological samples, probing depth (PD), plaque index (PI), and bleeding on probing (BOP) were obtained and documented from the mesiovestibular subgingival sulcus of the upper right first molar and left central incisor at the beginning of treatment and 3, 6, and 12 months later. Compliance with oral hygiene procedures, full mouth plaque score (FMPS), and full mouth bleeding score (FMBS) were assessed at the beginning of treatment and 12 months later. Two sample independent t-tests and the χ(2) test were used to study whether the indices of periodontal health differed in the teenagers due to the experimental conditions. RESULTS: None of the patients was positive for the periodontal anaerobes analyzed. The PI, PD, BOP, FMPS, and FMBS scores were significantly lower and compliance with oral hygiene was significantly higher in the group treated with Invisalign® than in the group treated with fixed brackets. CONCLUSION: Teenagers treated with removable appliances display better compliance with oral hygiene, less plaque, and fewer gingival inflammatory reactions than their peers with fixed appliances.

Incidence and distribution of coeliac disease in Campania (Italy): 2011-2013.

BACKGROUND: There exists a wide variation in the reported incidence of coeliac disease in recent decades. We aimed to evaluate the incidence rate of coeliac diagnoses performed in an Italian region, Campania, between 2011 and 2013 and its variation therein. METHODS: All coeliac diagnoses made from 2011 to 2013 and registered within the Campania coeliac disease register (CeliacDB) were identified. Incidence rates were analysed by sex, age and province of residence, with a Poisson model fitted to determine incidence rate ratios. RESULTS: We found 2049 coeliac disease diagnoses registered in the CeliacDB between 2011 and 2013; 1441 of these patients were female (70.4%) and 1059 were aged less than 19 years (51.7%). The overall incidence of coeliac disease in Campania was 11.8 per 100,000 person-years (95% CI 11.3-12.3) during the study period, with marked variation by age [27.4 per 100,000 person-years (95% CI 25.8-29.1) in children under 19 years of age and 7.3 per 100,000 (95% CI 6.8-7.8) in adults] and sex [16.1 per 100,000 person-years in females (95% CI 15.3-16.9) and 7.2 per 100,000 person-years in males (95% CI 6.6-7.8)]. Coeliac disease incidence was roughly similar in Naples, Salerno, Caserta and Avellino, but about half in Benevento. More than 80% of our study population was diagnosed by the combination of positive antitransglutaminase IgA and Marsh 3. More than half of the patients were symptomatic at the time of coeliac disease diagnosis (39.7% had a classical presentation and 21.1% a non-classical one according to the Oslo definition). CONCLUSIONS: Coeliac disease incidence was roughly similar among Campania provinces, except in Benevento where it was about half, probably due to less awareness of coeliac disease in this area. The incidence of coeliac disease in Campania appears to be lower than that reported by most of the previous literature, suggesting the necessity of new coeliac awareness programmes.

Contrasting land uses in Mediterranean agro-silvo-pastoral systems generated patchy diversity patterns of vascular plants and below-ground microorganisms.

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity.

"Unplugged," a European school-based program for substance use prevention among adolescents: overview of results from the EU-Dap trial.

The EU-Dap study aimed to develop and evaluate a school-based curriculum for the prevention of substance use among young people. The school curriculum, "Unplugged," is based on social influence approach and addresses social and personal skills, knowledge, and normative beliefs. It consists of 12 one-hour interactive sessions delivered by teachers. Its effectiveness was evaluated through a randomized trial involving 7,079 pupils of seven European countries. Unplugged was effective in reducing cigarette smoking, episodes of drunkenness, and the use of cannabis at short term. This association, however, was confined to boys, with age and self-esteem as possible explanations of this difference. Beneficial effects associated with the program persisted at fifteen-month follow-up for drunkenness, alcohol-related problems, and cannabis use, and were stronger among adolescents in schools of average low socioeconomic level. These results are of scientific importance and may inform the adoption of effective public health interventions at population level.

Human leukocyte antigen DQ2/8 prevalence in non-celiac patients with gastrointestinal diseases.

AIM: To investigate the prevalence of human leukocyte antigen (HLA) DQ2/8 alleles in Southern Italians with liver and gastrointestinal (GI) diseases outside of celiac disease. METHODS: HLA DQ2/8 status was assessed in 443 patients from three ambulatory gastroenterology clinics in Southern Italy (University of Federico II, Naples, Loreto Crispi Hospital, Ruggi D'Aragona Hospital, Salerno). Patients were grouped based on disease status [pre-post transplant liver disease, esophageal/gastric organic and functional diseases, irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD)] and DQ2/8 alleles, which correspond to a celiac disease genetic risk gradient. Subject allele frequencies were compared to healthy Italian controls. RESULTS: One hundred and ninety-six out of four hundred and forty-three (44.2%) subjects, median age 56 years and 42.6% female, were DQ2/8 positive. When stratifying by disease we found that 86/188 (45.7%) patients with liver disease were HLA DQ2/8 positive, 39/73 (53.4%) with functional upper GI diseases and 19/41 (46.3%) with organic upper GI diseases were positive. Furthermore, 38/105 (36.2%) patients with IBS and 14/36 (38.9%) with IBD were HLA DQ2/8 positive (P = 0.21). Compared to healthy controls those with functional upper GI diseases disorders had a 1.8 times higher odds of DQ2/8 positivity. Those with liver disease had 1.3 times the odds, albeit not statistically significant, of DQ2/8 positivity. Both those with IBS and IBD had a lower odds of DQ2/8 positivity compared to healthy controls. CONCLUSION: The proportion of individuals HLA DQ2/8 positive is higher in those with liver/upper functional GI disease and lower in IBS/IBD as compared to general population estimates.

Classroom characteristics and implementation of a substance use prevention curriculum in European countries.

BACKGROUND: Partial implementation may explain modest effectiveness of many school-based preventive programmes against substance use. We studied whether specific characteristics of the class could predict the level of implementation of a curriculum delivered by class teachers in schools from some European countries. METHODS: Secondary analysis of data from an evaluation trial. In seven European countries, 78 schools (173 classes) were randomly assigned to a 12-unit, interactive, standardized programme based on the comprehensive social influence model. Curriculum completeness, application fidelity, average unit duration and use of role-play were monitored using structured report forms. Predictors of implementation were measured by aggregating at class level information from the baseline student survey. Class size, gender composition, mean age, factors related to substance use and to affection to school were analysed, with associations estimated by multilevel regression models. RESULTS: Implementation was not significantly predicted by mean age, proportion of students with positive academic expectation or liking school. Proportion of boys was associated with a shorter time devoted to each unit [ß = -0.19, 95% confidence intervals (CI) -0.32 to -0.06]. Class size was inversely related to application fidelity [Odds ratio (OR) 0.92, 95% CI 0.85 to 0.99]. Prevalence of substance use was associated with a decreased odds of implementing all the curriculum units (OR 0.81, 95% CI 0.65 to 0.99). Students' connectedness to their class was associated with increased odds of teachers using role-play (OR 1.52, 95% CI 1.03 to 2.29). CONCLUSIONS: Teachers' implementation of preventive programmes may be affected by structural and social characteristics of classes and therefore benefit from organizational strategies and teachers' training in class management techniques.

Diversity and ecological characteristics of vascular flora in Mediterranean temporary pools.

Vascular flora of Mediterranean temporary pools has been studied with the aims to define its diversity and to individuate the ecological characteristics of the different plant groups associated with this relevant and endangered habitat type. Overall, 246 species were found of which 108 were terrestrial, 57 generalist of aquatic or wet habitats and 81 typical of temporary water and strongly linked to temporary pools. The results suggest that: (i) vascular flora associated with Sardinian Mediterranean temporary pools is rich and diversified; (ii) rare ferns are better represented than previously reported; (iii) plant species are generally heliophilous and acidophilous, specialized temporary pool species mainly differing from the unspecialized ones in relationship to their soil moisture requirements; (iv) these habitats are particularly important for maintaining regional freshwater biodiversity.

The effect of Teflon coating on the resistance to sliding of orthodontic archwires.

Teflon is an anti-adherent and aesthetic material. The aim of this study was to evaluate, in vitro, the influence of Teflon coating on the resistance to sliding (RS) of orthodontic archwires. For this purpose, Teflon-coated archwires were examined using frictional resistance tests by means of a universal testing machine and compared with conventional uncoated wires. Twelve types of archwires with round and rectangular sections (0.014, 0.018, and 0.018 × 0.025 inches) and of different materials (stainless steel and nickel-titanium) were tested with two passive self-ligating brackets (SmartClip™ and Opal(®)) and one active self-ligating bracket (Quick(®)). Each archwire-bracket combination was tested 10 times under 8 simulated clinical scenarios. Statistical comparisons were conducted between the uncoated and Teflon-coated archwires using Wilcoxon and Mann-Whitney tests, and linear regression analysis. For all bracket-archwire combinations, Teflon-coated archwires resulted lower friction than the corresponding uncoated archwires (P < 0.01). The results showed that Teflon coating has the potential to reduce RS of orthodontic archwires.