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New COVID-19 ventilation guidelines have resulted in higher energy consumption to maintain indoor air quality (IAQ), and energy efficiency has become a secondary concern. Despite the significance of the studies conducted on COVID-19 ventilation requirements, a comprehensive investigation of the associated energy challenges has not been discussed. This study aims to present a critical systematic review of the Coronavirus viral spreading risk mitigation through ventilation systems (VS) and its relation to energy use. COVID-19 heating, ventilation and air conditioning (HVAC)-related countermeasures proposed by industry professionals have been reviewed and their influence on operating VS and energy consumption have also been discussed. A critical review analysis was then conducted on publications from 2020 to 2022. Four research questions (RQs) have been selected for this review concerning i) maturity of the existing literature, ii) building types and occupancy profile, iii) ventilation types and effective control strategies and iv) challenges and related causes. The results reveal that employing HVAC auxiliary equipment is mostly effective and increased fresh air supply is the most significant challenge associated with increased energy consumption due to maintaining IAQ. Future studies should focus on novel approaches toward solving the apparently conflicting objectives of minimizing energy consumption and maximizing IAQ. Also, effective ventilation control strategies should be assessed in various buildings with different occupancy densities. The implications of this study can be useful for future development of this topic not only to enhance the energy efficiency of the VS but also to enable more resiliency and health in buildings., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

This dataset was collected for the purpose of applying fault detection and diagnosis (FDD) techniques to real data from an industrial facility. The data for an air handling unit (AHU) is extracted from a building management system (BMS) and aligned with the Project Haystack naming convention. This dataset differs from other publicly available datasets in three main ways. Firstly, the dataset does not contain fault detection ground truth. The lack of labelled datasets in the industrial setting is a significant limitation to the application of FDD techniques found in the literature. Secondly, unlike other publicly available datasets that typically record values every 1 min or 5 min, this dataset captures measurements at a lower frequency of every 15 min, which is due to data storage constraints. Thirdly, the dataset contains a myriad of data issues. For example, there are missing features, missing time intervals, and inaccurate data. Therefore, we hope this dataset will encourage the development of robust FDD techniques that are more suitable for real world applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

Te Tiriti o Waitangi , a treaty negotiated between Māori (the Indigenous peoples of Aotearoa) and the British Crown, affirmed Māori sovereignty and guaranteed the protection of hauora (health). The Waitangi Tribunal, established in 1975 to investigate alleged breaches of the agreement, released a major report in 2019 (registered as WAI 2575) about breaches of te Tiriti within the health sector in relation to primary care, legislation, and health policy. This article explores the implications of this report for the New Zealand health sector and the decolonial transformation of health systems. The tribunal found that the Crown has systematically contravened obligations under te Tiriti across the health sector. We complement the tribunal's findings, through critical analysis, to make five substantive recommendations: (1) the adoption of Tiriti -compliant legislation and policy; (2) recognition of extant Māori political authority ( tino rangatiratanga ); (3) strengthening of accountability mechanisms; (4) investment in Māori health; and (5) embedding equity and anti-racism within the health sector. These recommendations are critical for upholding te Tiriti obligations. We see these requirements as making significant contributions to decolonizing health systems and policy in Aotearoa and thereby contributing to aspirations for health equity as a transformative concept., Competing Interests: Competing interests: None declared., (Copyright © 2020 Came, O’Sullivan, Kidd, and McCreanor.)

This paper reviews the literature regarding possible complications, complication-free survival, and overall survival of fixed dental prostheses that use both implants and natural teeth as abutments. The paper also provides clinical guidelines for treatment based on this literature review. An electronic search utilizing the MEDLINE, BIOSIS Citation Index, and Web of Science™ Core Collection databases was undertaken, and a review of the 25 selected texts studying 22 different patient cohorts was carried out. From a total of 1610 implants reviewed, 40 were lost (33 due to loss of integration and 7 due to fracture), whereas, out of a total of 1301 teeth, 38 were lost, of which 16 were due to fracture. Seventy-three cases of tooth intrusion were detected. From a total of 676 frameworks reviewed (metal n = 645, Zirconia n = 31), 7 fractured, while veneer material fracture occurred in 70 out of 672 bridges. Overall, 502 out of 531 tooth-implant fixed prostheses (TIPFs) remained functional, and 336 out of 439 prostheses showed no technical or biological complications and remained functional. Rigid TIFPs permanently cemented to teeth with sufficient coronal structure and with limited use of prosthetic attachments offer a good long-term treatment option to patients with good oral hygiene following sound implant placement. This mode of treatment should be used when free-standing implant-supported options may not be possible. Larger randomized control studies and other clinical studies comparing tooth-to-implant-connected treatment with other forms of treatment are needed to better understand the place of TIFP treatment in oral rehabilitation.

The aim of this study was to describe Dental Foundation year one dentists' attitudes towards prosthodontic decision making for edentulous patients, and identify whether there are gender differences in these attitudes. All South West Deanery trainees were invited to take part in the study between May and June 2011 and a previously piloted questionnaire was administered to the trainees by their training programme directors. The questionnaire posed questions based upon a clinical scenario of discussing treatment options with patients. Seventy-two questionnaires were used in the analysis (91% overall response rate). Trainees perceived their own values to be less important than the patient's values ( p < 0.001) in decision making, but similar to the patient's friend's/relative's values ( p = 0.1). In addition, the trainees perceived the patient's values to be less important than their friend's/relatives ( p < 0.001). Sixty-six per cent of trainees acknowledged an influence from their own personal values on their presentation of material to patients who are in the process of choosing among different treatment options, and 87% thought their edentulous patients were satisfied with the decision making process when choosing among different treatment options. Fifty-eight per cent of trainees supported a strategy of negotiation between patients and clinicians (shared decision making). There was no strong evidence to suggest gender had an influence on the attitudes towards decision making. The finding of a consensus towards shared decision making in the attitudes of trainees, and no gender differences is encouraging and is supportive of UK dental schools' ability to foster ethical and professional values among dentists.

Objectives: The aim of this study was to create prototype glass ionomer cements (GICs) incorporating a concentrated paste of chlorhexidine-hexametaphosphate (CHX-HMP), and to investigate the long-term release of soluble chlorhexidine and the mechanical properties of the cements. The purpose is the design of a glass ionomer with sustained anticaries efficacy., Methods: CHX-HMP paste was prepared by mixing equimolar solutions of chlorhexidine digluconate and sodium hexametaphosphate, adjusting ionic strength, decanting and centrifuging. CHX-HMP paste was incorporated into a commercial GIC in substitution for glass powder at 0.00, 0.17, 0.34, 0.85 and 1.70% by mass CHX-HMP. Soluble chlorhexidine release into artificial saliva was observed over 436 days using absorbance at 255nm. Diametral tensile and compressive strength were measured after 7 days' setting (37°C, 100% humidity) and tensile strength after 436 days' aging in artificial saliva. 0.34% CHX-HMP GICs were tested for their ability to inhibit growth of Streptococcus mutans in vitro., Results: GICs supplemented with CHX-HMP exhibited a sustained dose-dependent release of soluble chlorhexidine. Diametral tensile strength of new specimens was unaffected up to and including 0.85% CHX-HMP, and individual values of tensile strength were unaffected by aging, but the proportion of CHX-HMP required to adversely affect tensile strength was lower after aging, at 0.34%. Compressive strength was adversely affected by CHX-HMP at substitutions of 0.85% CHX-HMP and above., Conclusions: Supplementing a GIC with CHX-HMP paste resulted in a cement which released soluble chlorhexidine for over 14 months in a dose dependent manner. 0.17% and 0.34% CHX-HMP did not adversely affect strength at baseline, and 0.17% CHX-HMP did not affect strength after aging. 0.34% CHX-HMP GICs inhibited growth of S. mutans at a mean distance of 2.34mm from the specimen, whereas control (0%) GICs did not inhibit bacterial growth., Clinical Significance: Although GICs release fluoride in vivo, there is inconclusive evidence regarding any clinical anticaries effect. In this study, GICs supplemented with a paste of chlorhexidine-hexametaphosphate (CHX-HMP) exhibited a sustained release of chlorhexidine over at least 14 months, and small additions of CHX-HMP did not adversely affect strength., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Dental implants are an increasingly popular solution to missing teeth. Implants are prone to colonisation by pathogenic oral bacteria which can lead to inflammation, destruction of bone and ultimately implant failure. The aim of this study was to investigate the use of chlorhexidine (CHX) hexametaphosphate (HMP) nanoparticles (NPs) with a total CHX concentration equivalent to 5 mM as a coating for dental implants. The CHX HMP NPs had mean diameter 49 nm and composition was confirmed showing presence of both chlorine and phosphorus. The NPs formed micrometer-sized aggregated surface deposits on commercially pure grade II titanium substrates following immersion-coating for 30 s. When CHX HMP NP-coated titanium specimens were immersed in deionised water, sustained release of soluble CHX was observed, both in the absence and presence of a salivary pellicle, for the duration of the study (99 days) without reaching a plateau. Control specimens exposed to a solution of aqueous 25 µM CHX (equivalent to the residual aqueous CHX present with the NPs) did not exhibit CHX release. CHX HMP NP-coated surfaces exhibited antimicrobial efficacy against oral primary colonising bacterium Streptococcus gordonii within 8 h. The antimicrobial efficacy was greater in the presence of an acquired pellicle which is postulated to be due to retention of soluble CHX by the pellicle.

Statement of Problem: The technique of immediate implant placement is said to have success rates similar to those of implantation into a healed socket. An implant-supported restoration in an esthetic area must achieve a harmonious balance of functional, esthetic, and biologic imperatives to be considered effective., Purpose: The purpose of this clinical study was to assess the height of the interproximal gingival papillae adjacent to immediate implants with immediate loading. The hypothesis was that specific positioning of the proximal contact areas of the interim crowns would facilitate the maintenance or regeneration of the interproximal papilla., Material and Methods: Twenty-eight participants were provided implants (n=36) in the anterior maxillary area that were loaded with a specifically contoured interim crown immediately after tooth extraction. The proximal contact areas of the interim crowns were positioned 5 to 6 mm incisal to the interproximal bony crest by using a prosthetic template. Papilla height was classified according to a previously described papilla index. A comparison was made between the papilla height before the extraction, at interim crown placement after the implant placement, and at 6 and 12 months postoperatively. Parametric and nonparametric tests were used when appropriate (Kolmogorov-Smirnov). Significance was expressed at the α=.05 level. Cross tables were used to describe the changes in the papilla index score., Results: During the 1-year follow-up, the score of the distal and mesial papilla indices increased significantly (repeated-measures Friedman exact test; P=.035 and P=.002)., Conclusions: This prospective study indicated that the use of a prosthetic template for positioning an interim crown on immediately placed implants and for ensuring that the proximal contact areas of the crown with adjacent teeth are 5 to 6 mm incisal to the interproximal bony crest does not seem to hinder the maintenance or regeneration of the height of the interproximal papillae., (Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Background: Glass ionomer cements (GICs) are a class of dental biomaterials. They have a wide range of uses including permanent restorations (fillings), cavity linings, fissure sealants and adhesives. One of the most common reasons for replacing a dental restoration is recurrent bacterial tooth decay around the margins of the biomaterial. Therefore, a dental biomaterial which creates a sustained antimicrobial environment around the restoration would be of considerable clinical benefit. In this manuscript, the formulation of a GIC containing novel antimicrobial nanoparticles composed of chlorhexidine hexametaphosphate at 1, 2, 5, 10 and 20% powder substitution by mass is reported. The aim is to create GICs which contain chlorhexidine-hexametaphosphate nanoparticles and characterize the nanoparticle size, morphology and charge and the release of chlorhexidine and fluoride, tensile strength and morphology of the GICs., Results: The GICs released chlorhexidine, which is a broad spectrum antimicrobial agent effective against a wide range of oral bacteria, over the duration of the experiment in a dose-dependent manner. This was not at the expense of other properties; fluoride release was not significantly affected by the substitution of antimicrobial nanoparticles in most formulations and internal structure appeared unaffected up to and including 10% substitution. Diametral tensile strength decreased numerically with substitutions of 10 and 20% nanoparticles but this difference was not statistically significant., Conclusion: A series of GICs functionalized with chlorhexidine-hexametaphosphate nanoparticles were created for the first time. These released chlorhexidine in a dose-dependent manner. These materials may find application in the development of a new generation of antimicrobial dental nanomaterials.

Objectives: Zirconia ceramic material has been widely used in implant dentistry. In this in vitro study the physiochemical properties of titanium and zirconia materials were investigated and the affinity of different bacteria to different materials was compared., Methods: Disc samples with different surface states were used: polished partially stabilized zirconia (PZ), titanium blasted with zirconia (TBZ), titanium blasted with zirconia then acid etched (TBZA), and polished titanium (PT) as a control. Surface topography was examined using scanning electron microscopy and profilometry. Contact angle, surface free energy (SFE), surface microhardness and chemical composition were determined. Disc samples were separately incubated with Streptococcus mitis and Prevotella nigrescens, either with or without pre-coating with human saliva, for 6h and the surface area covered by bacteria was calculated from fluorescence microscope images., Results: PZ and TBZ exhibited lower surface free energy and lesser surface wettability than PT. Also, PZ and TBZ surfaces showed lower percentage of bacterial adhesion compared with control PT surface., Conclusions: The zirconia material and titanium blasted with zirconia surface (TBZ surface) showed superior effect to titanium material in reducing the adhesion of the experimented bacteria especially after coating with saliva pellicle. Modifying titanium with zirconia lead to have the same surface properties of pure zirconia material in reducing bacterial adhesion. SFE appears to be the most important factors that determine initial bacterial adhesion to smooth surface., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The majority of dental implants are composed primarily of titanium and have an outer layer of titanium dioxide. Crystalline titanium dioxide most commonly exists in one of the two structures, anatase and rutile, and both of these have been observed on commercially available dental implants. Early implant failure can be associated with postoperative infection due to implant contamination during or immediately after surgery. The impetus of this study was to investigate whether functionalization of anatase and rutile titanium dioxide surfaces with chlorhexidine-reduced subsequent colonization of the surface by Streptococcus gordonii. Exposure to 100 mg x L(-1) chlorhexidine for 60 s resulted in a fivefold reduction in S. gordonii coverage on anatase and a twofold reduction on rutile. This may be related to a preferential adsorption of chlorhexidine to anatase compared with rutile. The reduction in bacterial coverage was not due to desorption of chlorhexidine into solution. More bacteria were observed on anatase than rutile surfaces without chlorhexidine functionalization, indicating that crystal structure may have a significant effect on bacterial colonization. In conclusion, functionalization with chlorhexidine reduced bacterial coverage on titanium dioxide surfaces, and anatase surfaces may be more amenable to such treatment than rutile., (Copyright 2008 Wiley Periodicals, Inc.)

This study investigated whether teaching undergraduate dental students the diagnosis and management of acute dental pain alongside the underpinning oral physiology helped them to understand the topic better than teaching them acute dental pain as a separate entity. Each of three clinical years of dental students at the same dental school was taught in two groups. Each group was taught the signs/symptoms of five acute dental pain conditions by the same member of the staff. However, the teaching for one group of students in each year reminded the students about the physiology that underpinned the clinical symptoms. One week later, the students completed an open-ended questionnaire that required them to list signs/symptoms of the five dental pain conditions. For each year of dental students that was examined, the mean student marks were significantly higher (p<0.05) for those who were taught dental pain and the underlying physiology compared with students who were only taught dental pain as a stand-alone subject. This suggests that integrating biomedical science and clinical teaching is beneficial.

Bacterial colonisation of exposed implant and abutment surfaces can lead to peri-implantitis, a common cause of oral implant failure. When an abutment becomes exposed in the oral environment the typical recommendation is to debride it, to obtain a smoother surface which might be expected to reduce bacterial colonisation. The aim of this study was to evaluate, in vitro, a conventional polishing protocol (PP1) and a simplified polishing protocol (PP2), suggested to have advantages over PP1. The surface morphology and roughness of titanium abutments were characterised at each stage of polishing, and adhesion of oral bacteria was evaluated, using atomic force microscopy, environmental scanning electron microscopy and optical profilometry. PP1 and PP2 methodologies resulted in indistinguishable surface finishes, with fewer scratches than the unmodified surface, and equal roughness values. PP2 resulted in less disruption and less removal of surface material. Early biofilm formation by Streptococcus mutans was reduced on surfaces polished using PP2, but not PP1. Biofilms of Actinomyces naeslundii were more extensive on polished abutment surfaces. Simplified protocol PP2 may be preferable to conventional protocol PP1, since less material is removed, and there is less chance of rough areas remaining. Polishing, however, does not necessarily reduce oral bacterial colonisation.

In 2000, the University of Bristol Dental School Division of Restorative Dentistry carried out a review of the assessment methods used within the undergraduate programme. Following this review, a number of key recommendations were made and the system of formative assessment within the division was changed. Audits were conducted immediately prior to the introduction of the new system and 2 years after it had been introduced, the results of these audits are presented. There was no change in the number of failed appointments between the initial audit and the second audit. There was a reduction in the number of patients treated by more than one student from 25% to 14% (approximating to 3% if student withdrawal from the course is taken into account). The length of time taken to complete treatment reduced between the two audits with more than half of all patients having their treatment completed within 3 months of their initial examination in the second audit. Ninety-five percent of treatment plans were completed in the second audit compared with only 62% in the first audit. In the second audit, the outstanding 5% of cases were signed off as incomplete for satisfactory reasons by the member of supervisory staff (e.g. patients who had moved away or were discharged due to poor attendance). Student comments were mostly positive, the small number of negative comments related to some students being confused by the paperwork in the new system. The overall process has been an extremely positive experience which has resulted in an assessment system with increased clarity which appears to have reduced the stress levels reported by the undergraduate students on the programme and improved the quality of patient care within restorative dentistry.

This clinical report describes an unusual consequence of peri-implantitis and subsequent implant failure in a 72-year-old man. Following uneventful implant removal, osteomyelitis developed at the implant site, which subsequently weakened the mandible sufficiently for a pathological fracture to occur. The patient was treated successfully by use of an intensive oral hygiene regime, antibiotics, and conservative management. The consequences and management of implant failure are discussed, as well as issues relating to the management of osteomyelitis and pathological bone fracture.

Objectives: The study presented was designed to analyse the mechanical performance and the primary and secondary stability characteristics of endosseous titanium implants with 1 degree (EXP1) and 2 degrees (EXP2) of taper when compared with the standard Brånemark design (Nobel Biocare AB, Gothenburg, Sweden)., Materials and Methods: One pair of 10 mm EXP1 and control implants were placed in the femoral condyles of six rabbits. Paired 6 mm EXP1 and control implants and 6 mm EXP2 and control implants were placed in the tibial metaphysis. The control implants used were 4 mm diameter standard Brånemark implants, the same length as the test implants. At placement, insertion torque (IT) and resonance frequency analysis (RFA) measurements were performed. Six weeks postoperatively when the animals were killed, RFA and removal torque (RT) measurements were made., Results: At placement, significantly higher IT was needed to insert the EXP implants compared with the controls. RFA values were significantly higher for EXP1 implants placed in the tibia but not in the femur. In pooling data from the femur and tibia there was a significant difference. The EXP2 implants failed to insert fully and demonstrated a lower RFA value than may have been expected due to the exposed threads, although this difference was not statistically significant., Conclusions: The results from the present study showed that 1 degrees of taper results in a better primary stability compared with the standard Brånemark design. There was no evidence that the tapered design caused negative bone tissue reactions. All the implants gained in stability during the healing period.

Background: Surgical technique and implant design have an effect on the primary stability of oral implants, which in turn increases resistance to implant micromotion during healing., Purpose: This study was designed to compare the parameters associated with implant insertion using two different methods of enhancing implant primary stability and to identify any relationship between these parameters and changes in the stability of implants during the initial 6-month healing period following implant insertion. A comparison was made between two methods of enhancing primary implant stability: method 1, standard Brånemark System implants (Nobel Biocare AB, Gothenburg, Sweden) inserted with a technique designed to enhance primary stability, and method 2: Brånemark Mk IV implants (Nobel Biocare AB) inserted according to the manufacturer's instructions., Materials and Methods: Thirteen patients were selected for inclusion in the study. A total of 42 implants were placed. Insertion torque data were recorded, and bone quality at the implant site was assessed at implant insertion. Resonance frequency analysis measurements were taken at implant insertion as well as at second-stage surgery 6 months later., Results: A statistically significant difference was recorded between the mean maximum insertion torque for type 4 bone and bone types 2 and 3. No significant difference was recorded between bone types 2 and 3. A significantly lower resonance frequency value was seen for standard implants placed into type 4 bone (p < .05). Across all implant types a significant difference in the energy required when inserting implants into type 4 bone and bone types 2 and 3 was seen. A significantly lower mean energy requirement was seen between the Mk IV implants placed into type 4 bone and the other combinations of implant types and bone., Conclusions: Within the limitations of this study, the results agree with the manufacturer's claim that when compared with standard implants, the design of the Mk IV implant increases implant primary stability with a reduction in the energy imparted into the bone at the implant site.