Publications by authors named "Karl M Lyons"

Statement Of Problem: Denture stomatitis can pose serious health risks, especially to older people. Chemical denture cleaning agents must be effective, yet not adversely affect the longevity of removable dentures. Ready-to-use (RTU) neutral pH electrolyzed oxidizing water (EOW) is an effective biocide against Candida albicans biofilms on denture resins, but the effects of daily disinfection with EOW on the physical and mechanical properties of resins have not been established.

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Objectives: The objective of this scoping review was to map evidence of electrolysed oxidising water (EOW) as a biocide for dental applications of relevance to older people and identify research gaps.

Background: EOW is an emerging, "green," and cost-effective biocide. There are no reviews on the landscape of EOW research as either an antiseptic or disinfectant in dental healthcare or its suitability for the oral healthcare of older people.

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Colonization of surfaces in the human body by microorganisms is an early, essential, step in the initiation of infectious disease. We have developed in vitro assays to investigate interactions between yeast or bacterial cells and human tissues, fluids, or prostheses. Such assays can be used to identify the adhesins, ligands, and receptors involved in these interactions, for example, by determining which components of the microbe or human tissue/fluid interfere with adherence in the assay.

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The influence of thermocycling on the surface deterioration of glazed monolithic high translucent 3Y-TZP dental restorations is still unclear. The purpose of this study therefore was to evaluate low temperature degradation (LTD), elemental release and surface degradation pattern after five years of simulated clinical time. A total of 123 specimens were prepared from second-generation high translucent 3Y-TZP as per ISO 6872:2015 standards (3 mm × 4 mm × 30 mm).

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The aims of this study were to investigate the clinical effectiveness and patient acceptability of a modified glass ionomer cement placed using the atraumatic restorative treatment (ART) technique to treat root caries, and to carry out microbiological analysis of the restored sites. Two clinically visible root surface carious lesions per participant were restored using ART. One was restored with commercial glass ionomer cement (GIC) (ChemFil Superior, DENTSPLY, Konstonz, Germany) which acted as the control.

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The aim of the study was to investigate the microbial colonization (by species, anaerobic and facultative anaerobic bacteria) of maxillary obturators used for the restoration of maxillary defects, including during radiotherapy. Retrospective cohort study. Fifteen patients requiring a maxillary obturator prosthesis had swabs of their obturators and adjacent tissues taken at different stages of their treatment over a period of 8 years.

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(1) Background: The effect of glazing on the mechanical properties of monolithic high translucent zirconia is not well reported. Therefore, the purpose of this study was to evaluate the effect of glazing on the flexural strength of high translucent zirconia; (2) Methods: Ninety specimens were prepared from second-generation 3Y-TZP high translucent blocks and divided into three groups. Glaze materials were applied on one surface of the specimen and subjected to a four-point bending test and flexural stress and flexural displacement values were derived.

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Objectives: To compare tooth colour change and participant's satisfaction following: home (HB), in-office (IOB) and combined (CB) bleaching treatments.

Methods: A group of 105 participants received HB, IOB and CB treatments. HB was performed using custom-made trays and 10 % carbamide peroxide for 14 days.

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Background: Maxillofacial prosthetics includes restoration of maxillary defects resulting from resection of palate and nasosinus neoplasms with obturator prostheses which may be colonized by microorganisms and function as a reservoir of infection. Patients with neoplasms commonly also require radiotherapy that can result in changes in saliva quality and quantity and changes in the oral microbial flora. The altered flora, in individuals immunocompromised from cancer therapy, increases their risk of prosthesis-related infections.

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Purpose: To assess any correlations between resonance frequency analysis (RFA) and other clinical measurements, namely changes in marginal bone level.

Materials And Methods: A systematic review was performed to investigate the relationship between RFA and changes in marginal bone level. Clinical studies published up to May 1, 2018, were searched in electronic databases, including PubMed/MEDLINE, Embase, and Cochrane, using the following MeSH terms: resonance frequency analysis; implant stability quotient; RFA; and ISQ, in combination with marginal bone level; marginal bone loss; and marginal bone resorption.

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Objective: Personality characteristics mean that people may interpret similar symptoms differently, complicating the measurement of self-reported oral health, and so we tested the hypothesis that controlling for aspects of personality makes a difference to the association between xerostomia and oral-health-related quality of life.

Material And Methods: A cross-sectional study was conducted of a representative adult population sample in Dunedin (New Zealand). Data were collected on xerostomia, OHRQoL and personality characteristics, using (respectively) the 5-item Shortened Xerostomia Inventory (SXI), the OHIP-14 and the Positive and Negative Affect Schedule (PANAS).

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Objective/aims: The aim of this study was to measure continuously the intraoral pH and temperature of healthy individuals to investigate their diurnal variations.

Materials And Methods: Seventeen participants (mean age, 31±9 years) wore a custom-made intraoral appliance fitted with a pH probe and thermocouple for two sets of 24 h, while carrying out normal daily activities including sleep. The continuous changes in intraoral pH and temperature were captured using a sensor placed on the palatal aspect of the upper central incisors.

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Periodontics cannot be practiced in isolation as frequently many patients have multiple dental needs or medical health issues requiring management. In addition, pathology may manifest in the periodontal tissues, and the onset and progression of periodontitis can be affected by systemic conditions, such as diabetes, and vice versa. The focus of this volume of Periodontology 2000 is interdisciplinary periodontics, and the articles included discuss the interactions and the interrelationshipbetween periodontal tissues/periodontal diseases and endodontics, fixed prosthodontics, implant dentistry, esthetics, gerodontology, radiology, orthodontics, pediatric dentistry, oral and maxillofacial surgery, oral pathology, special needs dentistry and general medicine.

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Esthetic considerations are a significant contributing factor in the management of prosthodontic cases and an interdisciplinary approach is often necessary to achieve an optimal result. The visible soft-tissue architecture plays a key role in developing an esthetic smile. Furthermore, an understanding of the relationship between the restorative margin and the gingiva is important for long-term stability of the result.

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Although periodontal factors do not usually have a direct effect on the survival of a fixed prosthesis, harmony between the prosthesis and the periodontium is critical otherwise esthetics, the longevity of the prosthesis and the periodontium will be compromised. A close interdisciplinary relationship between periodontics and prosthodontics is therefore necessary to avoid an unsatisfactory treatment outcome, requiring extensive and expensive retreatment. The design of the prosthesis, the number and quality of the abutment teeth, the preparation and the pontic, the occlusion and the material need to be considered when planning prosthodontic treatment.

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Colonization of surfaces in the human body by microorganisms is an early, essential, step in the initiation of infectious disease. We have developed in vitro assays to investigate interactions between yeast or bacterial cells and human tissues, fluids, or prostheses. Such assays can be used to identify the adhesins, ligands, and receptors involved in these interactions, for example, by determining which components of the microbe or human tissue/fluid interfere with adherence in the assay.

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Purpose Of Study: The severity of tooth wear is known to have an association with intraoral pH and temperature depending on the site.

Objective: To compare the intraoral pH and temperature between the maxillary and mandibular arch.

Methods: Fourteen participants (mean age=25.

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With the Internet facilitating access to vast amounts of free information, dental practitioners face providing treatment for an increasingly informed public. However, the available content is not filtered, and it can be difficult for patients to discriminate between research-informed evidence and "glamorised" material of dubious origin. Patients reasonably expect a return for their investment and want to know how long their treatment will last.

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Purpose: The purpose of this in vitro study was to evaluate porcelain cracking induced by abrasive grinding with a conventional dental air turbine and abrasive diamond burs.

Materials And Methods: Four commercially available porcelains were examined-Wieland ALLUX, Wieland ZIROX, IPS e.max Ceram, and IPS Empress Esthetic Veneering porcelain.

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Objective: To identify the techniques most commonly used in New Zealand for gingival retraction for impressions of natural teeth and implants in fixed prosthodontics.

Design: Postal survey of a random sample of dentists

Methods: A questionnaire was mailed to all members of the New Zealand Dental Association (NZDA). Data were analysed using SPSS.

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Colonization of surfaces in the human body by microorganisms is an early, essential, step in the initiation of infectious disease. We have developed in vitro assays to investigate interactions between yeast or bacterial cells and human tissues, fluids, or prostheses. Such assays can be used to identify the adhesins, ligands, and receptors involved in these interactions, for example by determining which components of the microbe or human tissue/fluid interfere with adherence in the assay.

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Objectives: The aim of this study was to compare the colour matching ability of instrumental colorimetry with that of a conventional visual colour matching technique.

Setting: The study was conducted in a dental clinic at the University of Otago, School of Dentistry, New Zealand.

Materials And Methods: Three dentists with normal colour vision used a Vita Classical shade guide to determine the shade of the maxillary right central incisor of 10 randomly chosen individuals.

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