Browsing by Author "Lynch, Edward"
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Item Metadata only A systematic literature review on the role of lasers in endodontic therapy: Valuable adjunct treatment?(MDPI, 2020-07-01) Anagnostaki, Eugenia; Mylona, Valina; Parker, Steven; Lynch, Edward; Grootveld, Martin(1) Background: Adjunctive instruments, such as lasers have been investigated to address the risk of failure of endodontic therapy due to the complexity of the root canal system. Lasers have been used therapeutically, in direct irradiation of the root canals or adjunct to irrigants placed into the canals, in combination with a photosensitizer (antimicrobial photodynamic therapy) and in pain management (photobiomodulation). The purpose of this systematic review was to evaluate the evidence in clinical use within these three areas of therapy. (2) Methods: PubMed, Cochrane and Scopus search engines were used to identify human clinical trials regarding the use of lasers in endodontic therapy. (3) Results: After applying the keywords and additional filters, inclusion and exclusion criteria, the initial number of 1486 articles was reduced to 17. It was revealed that almost all studies (14/17) presented a statistically significant improved outcome in laser-assisted endodontic therapy, with the remaining three not showing any adverse effects. (4) Conclusions: The use of laser photonic energy of appropriate delivered parameters can be proposed as useful adjunctive when considering optimal treatment modalities in orthograde endodontics. Additionally, a tendency of research towards pain modulation in this field is developing.Item Open Access Current Concepts of Laser–Oral Tissue Interaction.(MDPI, 2020-06-28) Parker, Steven; Anagnostaki, Eugenia; Mylona, Valina; Cronshaw, Mark; Lynch, Edward; Grootveld, MartinFundamental to the adjunctive use of laser photonic energy for delivering therapy and tissue management, is the ability of the incident energy to be absorbed by target tissues. The aim of this review is to examine the differential performance of the separate components of oral hard and soft tissues when exposed to laser photonic irradiance of variable wavelengths and power values. Through an examination of peer-reviewed published data and materials, the interaction of laser photonic energy and target tissues are explored in detail. Varying laser wavelength emissions relative to anatomical structures explores the ability to optimise laser–tissue interactions, and also identifies possible risk scenarios as they apply to adjacent non-target structures. The concepts and practical aspects of laser photonic energy interactions with target oral tissues are clearly demonstrated. Emphasis was placed on optimising the minimum level of laser power delivery in order to achieve a desired tissue effect, whilst minimising the risk or outcome of collateral tissue damage.Item Metadata only Effect of Photobiomodulation Therapy Dosage on Orthodontic Movement, Temporomandibular Dysfunction and Third Molar Surgery Outcomes: A Five-Year Systematic Review(MDPI, 2024-04-04) Parker, Steven; Cronshaw, Mark; Anagnostaki, Eugenia; Mylona, Valina; Lynch, Edward; Grootveld, Martin(1) Background: This five-year systematic review seeks to assess the impact of oral and peri-oral photobiomodulation therapies (PBMTs) on the adjunctive management of deeper tissue biofunction, pathologies related to pain and inflammatory disorders and post-surgical events. (2) Methods: The search engines PubMed, Cochrane, Scopus, ScienceDirect, Google Scholar, EMBASE and EBSCO were used with appropriate Boolean operatives. The initial number of 14,932 articles was reduced to 261. Further exclusions performed to identify PBM therapy in third molar surgery, orthodontic and TMJ articles resulted in 19, 15 and 20 of these, respectively. Each paper was scrutinised to identify visible red–NIR laser wavelength PBM applications, concerning dosimetry and outcomes. (3) Results: A dataset analysis was employed using post hoc ANOVA and linear regression strategies, both with a Bonferroni correction (p < 0.05). The outcomes of articles related to oral surgery pain revealed a statistically significant relation between PBMT and a positive adjunct (p = 0.00625), whereas biofunction stimulation across all other groupings failed to establish a positive association for PBMT. (4) Conclusions: The lack of significance is suggested to be attributable to a lack of operational detail relating to laser operating parameters, together with variation in a consistent clinical technique. The adoption of a consistent parameter recording and the possible inclusion of laser data within ethical approval applications may help to address the shortcomings in the objective benefits of laser PBMItem Open Access Laser-Assisted aPDT Protocols in Randomized Controlled Clinical Trials in Dentistry: A Systematic Review(MDPI, 2020-09-22) Mylona, Valina; Anagnostaki, Eugenia; Parker, Steven; Cronshaw, Mark; Lynch, Edward; Grootveld, MartinBackground: Antimicrobial photodynamic therapy (aPDT) has been proposed as an effective alternative method for the adjunctive treatment of all classes of oral infections. The multifactorial nature of its mechanism of action correlates with various influencing factors, involving parameters concerning both the photosensitizer and the light delivery system. This study aims to critically evaluate the recorded parameters of aPDT applications that use lasers as the light source in randomized clinical trials in dentistry. Methods: PubMedandCochrane search engineswere used to identifyhuman clinical trials of aPDT therapy in dentistry. After applying specific keywords, additional filters, inclusion and exclusion criteria, the initial number of 7744 articles was reduced to 38. Results: Almost one-half of the articles presented incomplete parameters, whilst the others had different protocols, even with the same photosensitizer and for the same field of application. Conclusions: No safe recommendation for aPDT protocols can be extrapolated for clinical use. Further research investigations should be performed with clear protocols, so that standardization for their potential dental applications can be achieved.Item Metadata only Photobiomodulation and Oral Mucositis: A Systematic Review(MDPI, 2020-08-05) Cronshaw, Mark; Parker, Steven; Anagnostaki, Eugenia; Mylona, Valina; Lynch, Edward; Grootveld, MartinOral mucositis (OM) is a debilitating complication of chemotherapy, and head and neck radiotherapy. In an effort to offer the best possible advice within the limitations of published research, a systematic review with an extended discussion and commentary on dosimetry and dose delivery is presented. Using keywords as listed, Pubmed, Google Scholar and Cochrane databases were searched during a period extending from 1995 to 2019. A total of 782 abstracts were identified. A total of 50 papers were analysed, and of these, 29 satisfied criteria required for systematic review in accordance with an optimized PRISMA statement. Clinical outcome as reported was subject to analysis with respect to time of intervention, incidence and severity of oral mucositis, and pain amelioration, and a comprehensive combined univariate and multivariate statistical analysis of the methods employed was performed. Recommendations are made with respect to the timing of the intervention. Moreover, there is an extended discussion available on the treatment care rationale of photobiomodulation (PBM), and its adjunctive association with OM. In conclusion, early prophylactic application offers clear advantages in clinical management. The many studies and associated variables and covariables assessed here revealed a choice of delivery techniques, associated wavelengths and many further indices to consider with regard to the accomplishment of optical parameters. It is therefore our recommendation that clinicians use PBM as a therapy with a full and proper understanding and training in order to optimise the clinical effects achievable.Item Metadata only Photobiomodulation Dose Parameters in Dentistry: A Systematic Review and Meta-Analysis(MDPI, 2020-10-06) Cronshaw, Mark; Parker, Steven; Anagnostaki, Eugenia; Mylona, Valina; Lynch, Edward; Grootveld, MartinObjective: This systematic review and meta-analysis of published randomized controlled trials examines a possible relationship between optical spot size at surface tissue, irradiance, radiant exposure, total energy delivered, operator technique and reported clinical outcomes. Background: Clinical photobiomodulation (PBM) therapy has achieved a high level of evidence-based acceptance in the mitigation of oral mucositis associated with cancer radiotherapy and chemotherapy, and supportive clinical research in relation to orthodontic tooth movement, oral medical conditions, including burning mouth syndrome, xerostomia and lichen planus. Inconsistent outcomes have been reported not withstanding a substantial body of primary supportive research from clinical, in vitro and animal studies. Materials and Methods: PubMed, Cochrane Database of Reviews and Google Scholar search engines were applied to identify human clinical trials of PBM therapy in clinical dentistry. A total of 766 articles between February 2009 and June 2020 were identified and following a full text evaluation, 38 papers with sufficient data to permit analyses are included in this investigation. Results: Following a detailed assessment of potential factors that may have an influence in clinical outcome, a clear trend is apparent associating optical spot size to a positive or negative effect. Furthermore, there is a clear difference in the reported results in relation to total energy applied, delivery techniques and optical parameters, which merits further investigation. Factorial statistical analyses identified an association between smaller optical surface applications and an overall lower level of reported clinical success in treating superficial and deeper targets, and correspondingly sub-surface larger target tissues were found to be more responsive to therapy by use of a larger optical surface spot size. Moreover, use of multiple small diameter probe applications was found to provide inconsistent results. Conclusions: Many factors can confound clinical success including variations in anatomy, site location, clinical condition and subject individuality. To achieve higher levels of predictable outcome, a mature appreciation of these factors, plus an expanded understanding of laser parametry, tissue volume and target depth to deliver an adequate dose within current recommended guidelines, is essential.Item Embargo Photobiomodulation Effects on Periodontal Ligament Stem Cells: A Systematic Review of In Vitro Studies(Bentham Science Publishers, 2022-04-12) Mylona, Valina; Anagnostaki, Eugenia; Chiniforush, Nasim; Barikani, Hamidreza; Lynch, Edward; Grootveld, MartinBackground: Stem cell therapy has been considered to play a paramount role in the treatment modalities available for regenerative dentistry. The established beneficial effects of photobiomodulation (PBM) at the cellular level have led to the combined use of these two factors (PBM and stem cells). The main goal of this study was firstly to critically appraise the effects of PBM on periodontal ligament stem cells (PDLSCs), and secondly to explore the most effective PBM protocols applied. Methods: Pubmed, Cochrane, Scopus, Science Direct, and Google Scholar search engines were used to identify experimental in vitro studies in which PBM was applied to cultured PDLSCs. After applying specific keywords, additional filters, and inclusion/exclusion criteria, a preliminary number of 245 articles were narrowed down to 11 in which lasers and LEDs were used within the 630 - 1064 nm wavelength range. Selected articles were further assessed by three independent reviewers for strict compliance with PRISMA guidelines, and a modified Cochrane risk of bias to determine eligibility. Statistical Analysis: The dataset analysed was extracted from the studies with sufficient and clearly pre- sented PBM protocols. Simple univariate regression analysis was performed to explore the significance of contributions of potential quantitative predictor variables toward study outcomes, and a one-way ANOVA model was employed for testing differences between the laser or LED sources of the treatments. The sig- nificance level for testing was set at α = 0.05. Results: The proliferation rate, osteogenic differentiation, and expression of different indicative genes for osteogenesis and inflammation suppression were found to be positively affected by the application of various types of lasers and LEDs. With regard to the PBM protocol, only the wavelength variable ap- peared to affect the treatment outcome; indeed, the 940 nm wavelength parameter was found not to exert a favourable effect. Conclusions: Photobiomodulation can enhance the stemness and differentiation capacities of periodontal ligament stem cells. Therefore, for PBM protocols, there remains no consensus amongst the scientific community. Statistical analyses performed here indicated that the employment of a near-infrared (NIR) wavelength of 940 nm may not yield a significant favourable outcome, although those within the 630 - 830 nm range did so. Concerning the fluence, it should not exceed 8 J/cm2 when therapy is applied by LED devices, and 4 J/cm2 when applied by lasers, respectively.Item Metadata only Photothermal Effects of High-Energy Photobiomodulation Therapies: An In Vitro Investigation(MDPI, 2023-06-04) Cronshaw, Mark; Parker, Steven; Grootveld, Martin; Lynch, EdwardThe purpose of this study was to investigate photothermal aspects of photobiomodulation therapies (PBMT) in vitro to assist in the development of safe clinical parameters with respect to higher-power devices with large surface applicators. Laser wavelengths in the range of 650 nm–1064 nm were investigated using a thermal camera. Thermographic measures of surface and sub-surface temperature variations of similar lean porcine muscle tissue samples were recorded for a series of calibrated experiments. A thermal comparison was then made between Flat-top and Gaussian beam spatial distribution devices. Outcome data were subjected to statistical analysis using an ANOVA model. Results acquired at similar parameters of irradiance indicated that the application of the 980 nm wavelength was associated with the highest rise in temperature, which decreased with other wavelengths in the order 980 > 1064 ≈ 650 >>> 810 nm (p < 5 × 10−20). All wavelengths assessed were associated with a significant temperature increase, and with the exception of 810 nm, all exceeded the threshold of a 6 °C rise within the prescribed parameter limits. Optical scanning by movement of the applied source over a relevant area was found to offer effective mitigation of these temperature increases. An extended discussion is presented, analysing the clinical significance of the study outcomes. Recommendations are made within the limits of this in vitro study in order to assist future clinical investigations.Item Metadata only Potential Advantages of Peroxoborates and Their Ester Adducts Over Hydrogen Peroxide as Therapeutic Agents in Oral Healthcare Products: Chemical/Biochemical Reactivity Considerations In Vitro, Ex Vivo And In Vivo(MDPI, 2020-08-07) Grootveld, Martin; Lynch, Edward; Page, Georgina; Chan, W.; Percival, Benita; Anagnostaki, Eugenia; Mylona, Valina; Bordin-Aykroyd, Sonia; Grootveld, KerryPeroxides present in oral healthcare products generally exert favourable protective activities against the development and progression of tooth decay, plaque, gingivitis, and halitosis, etc. However, despite the high level of research focus on hydrogen and carbamide peroxides as therapeutically active (and tooth-whitening) agents, to date the use of alternative chemical forms of peroxides such as peroxoborates for these purposes has received only scant attention. Intriguingly, peroxoborate and its esters with polyols, such as glycerol, have a very diverse chemistry/biochemistry in aqueous solution, for which there is an increasing amount of evidence that it remains distinctive from that of hydrogen peroxide; such properties include self-associative and hydrolytic equilibria, and their abilities to participate in electrophile- or nucleophile-scavenging, metal ion-complexing, redox and free radical reactions, for example. Therefore, the purpose of this detailed commentary is to evaluate both differences and similarities between the molecular/biomolecular reactivities of peroxoborate species and hydrogen peroxide in vitro, ex-vivo and in vivo. It encompasses brief sectional accounts regarding the molecular heterogeneity of peroxoborates, the release of bioactive agents therefrom, and their oxidative attack on oral cavity biomolecules (the nucleophilic or electrophilic character of these oxidations are discussed). Further areas explored are the abilities of borates and peroxoborates to enhance the solubility of iron ions in aqueous solution, their involvements in free radical biochemistry (particularly the complexation of oxygen radical-promoting transition metal ions by, and antioxidant properties of, peroxoborate-polyol ester adducts), and the specific inhibition of protease enzymes. Further aspects focus on the tooth-whitening, oral malodor neutralizing, and potential mutagenic and genotoxic properties of peroxoborates, along with possible mechanisms for these processes. The abilities of peroxoborates, and peroxides in general, to modulate the activities of inflammatory mediators and vitamins, antioxidant or otherwise, are also explored.Item Embargo Systematic review of post-surgical laser-assisted oral soft tissue outcomes using surgical wavelengths outside the 650–1350 nm optical window.(Mary Ann Liebert Inc, 2020-10-07) Parker, Steven; Anagnostaki, Eugenia; Mylona, Valina; Cronshaw, Mark; Lynch, Edward; Grootveld, MartinObjective: To explore via systematic review the validation of uneventful post-surgical healing, associated with shorter and longer laser wavelength applications in minor oral surgery procedures. Methods: From April 28 to May 11, 2020, PubMed, Cochrane Database of Systemic Reviews, and Google Scholar search engines were applied to identify human clinical trials of photobiomodulation (PBM) therapy in clinical dentistry. The searches were carried out with reference to (1) dental laser wavelengths shorter than 650 nm; (2) wavelengths localized within the 2780-2940 nm; and (3) the 9300-10,600 nm range. Selected articles were further assessed by three independent reviewers for strict compliance with PRISMA guidelines and modified Cochrane Risk of Bias to determine eligibility. Results: Using selection filters of randomized clinical trials, moderate/low risk of bias, and the applied period, and following PRISMA guidelines, 25 articles were selected and examined. A risk of bias was completed, where 11 out of 25 publications were classified as low risk of bias, and 14 out of 25 were classified as medium risk status. In total, 6 out of 13 (46% of) studies comparing the examined laser wavelengths with scalpel-based treatment showed positive results, whereas 6 out of 13 (46%) showed no difference, and only 1 out of 13 (7.7%) presented a negative outcome. In addition, 5 out of 6 (83% of) studies comparing the examined laser wavelengths with other diodes (808-980 nm) showed positive results, whereas 1 out of 6 (17%) had negative outcomes. Conclusions: A detailed and blinded examination of published studies has been undertaken, applying strict criteria to demonstrate research outcome data, which suggests positive or at worst neutral comparatives when a given laser wavelength system is used against an alternative control therapy. As such, substantiated evidence for laser surgery in delivering uneventful healing and analgesic effects, as an expression of a PBM-like (quasi-PBM) influence, has been shown.Item Metadata only Title: Dental anxiety in first- and final-year Indian dental students(Springer Nature, 2019-10-16) Grootveld, Martin; Chowdhury, Chitta Ranjan; Khijmatgar, Shahnawaz; Chowdhury, Avidyuti; Harding, Stewart; Lynch, EdwardAbstract Objectives: The study aims to investigate dental anxiety in first- and final-year undergraduate dental students in India. Design: Questionnaire Study Setting: BDS Students in four University dental colleges in India carried-out during 2013 and 2014. Subjects (materials and methods): The students (n = 614) were assessed using a pre-tested questionnaire. We estimated the level of dental anxiety by using the Modified-Dental-Anxiety-Scale (MDAS). ANCOVA and Mann-Whitney U, and Chi-squared contingency tests were employed to analyse the extensive dataset acquired. Univariate clustering analysis and principal component regression were also applied. Students had similar demographic and lifestyle patterns. Interventions: Assessments of the level of dental anxiety amongst undergraduate dental students Main outcome measures: Mean±SD MDAS scores for first- and final-year Bachelor of Dental Surgery (BDS) students were acquired. Results: Six hundred and fourteen (n = 614) students from four dental colleges were included in this study. Seventy-seven % were female (n=478) and 23% were male (n=136). The mean age of the first- and final-year students were 18.31 and 21.54 years respectively. First-year BDS students had an increased level of dental anxiety (Mean±SD 12.96±4.00) compared to that of the final-year ones (10.54±3.41), a difference which was very highly statistically significant (p<0.0001). Conclusion(s): Dental anxiety was significantly higher amongst first year BDS students over that of final-year students.Item Open Access Twelve Hour Longevity of the Oral Malodor-Neutralizing Capacity of an Oral Rinse Product Containing the Chlorine Dioxide Precursor Sodium Chlorite(The Biomedica, 2018-02-20) Grootveld, Kerry; Lynch, Edward; Grootveld, MartinObjectives: The objectives of this investigation were to investigate the effectiveness and longevity of an oral rinse product containing 0.10% (w/v) of the chlorine dioxide precursor sodium chlorite (1) on oral malodor in participants throughout a 12 h daylight diurnal cycle. Materials and methods: Thirty healthy participants (17 male, 13 female) were recruited to the study. Volatile sulfur compound levels (VSCs: H2S, CH3SH and (CH3)2S) were simultaneously monitored in their oral cavity air samples both before (0 h) and at 0.33, 4, 8 and 12 h after using the above oral rinse, or water as a negative control (participants refrained from oral hygiene measures during this 12 h period). The experimental design for this cross-over investigation was a mixed model ANOVA-based system incorporating treatments, sampling time-points and participants, together with their first-order interactions, as components of variance. Results: Results acquired demonstrated that the oral rinse formulation effectively suppressed VSC production in the oral environment for 12 h periods (p<0.0001, 0.0001 and 0.002 for H2S, CH3SH and (CH3)2S respectively). Mean 0 vs 12 h reductions in oral cavity H2S and CH3SH concentrations were much greater than those observed for the H2O negative control (p<10-8), but not so for (CH3)2S. Principal component analysis (PCA) a H2S/CH3SH linear combination and (CH3)2S alone significantly loaded on the first and second separate orthogonal components respectively, an observation confirming differing sources for these variable sets. Conclusions: The oral rinse explored effectively blocked VSC production in the oral cavity for a period of 12 h. This extended efficacy duration is likely to be ascribable to the ability of its active ClO2- ingredient to exert a combination of biochemical (direct VSC- and amino acid VSC precursor-consuming) and microbicidal actions in vivo. Clinical relevance: The 12 h longevity of product’s# oral malodor-neutralizing actions is of much clinical significance in view of the involvements of VSCs, particularly CH3SH, in the pathogenesis of gingivitis and periodontitisItem Metadata only Undesirable and adverse effects of tooth-whitening products: a review.(Springer, 2010) Goldberg, Michel; Grootveld, Martin; Lynch, EdwardHydrogen peroxide (H2O2) is a powerful oxidising agent. It gives rise to agents known to be effective bleaching agents. The mechanisms of bleaching involve the degradation of the extracellular matrix and oxidation of chromophores located within enamel and dentin. However, H2O2 produces also local undesirable effects on tooth structures and oral mucosa. In clinical conditions, the daily low-level doses used to produce tooth whitening never generate general acute and sub-acute toxic effects. Genotoxicity and carcinogenicity only occur at concentrations that are never reached during dental treatments. Some transient adverse effects have been reported on the oral mucosa and the digestive tract if the product is swallowed. Local effects may occur on the oral mucosa and dental tissues during whitening, namely, pulp sensitivity, cervical resorption, release of selected components of dental restorative materials, and alteration of the enamel surface. Most of the local effects are dependent of the technique and concentration of the product so far used, but as the results of bleaching obtained are not stable, repeated treatments add to the adverse effects. The informed decision to administer or not and the control of bleaching effects should stand in the hand of dental surgeons and certainly not as it appears at present, as cosmetics sold without any restriction despite the potential health hazards of peroxides.