Laurence James Walsh

University of Queensland | UQ · School of Dentistry

Introduction: Ablation of human enamel and dentin, with no collateral damage is essential for lasers to be used for clinical applications in dentistry. This study for the first time explores efficacy and surface topography resulting from interaction of a novel ultra-short femtosecond (30-fs) laser with enamel and dentin following laser irradiation...

Purpose This systematic review explored the use of photobiomodulation (PBM) to achieve analgesia, reduce dental pain, and reverse the effects of local anesthetic (LA) agents, without injuring soft tissues through thermal effects. Methods Electronic searches were undertaken in PubMed, Embase, Google Scholar, and SPIE digital databases, according to...

Background: Older adults in residential aged care facilities (RACFs) experience disproportionate levels of poor oral health relative to other groups in the general population, affecting their physical and mental wellbeing. The Oral Health Assessment Tool (OHAT) is a validated and widely used dental assessment tool; however, recent systematic review...

This clinical study assessed photobiomodulation (PBM) induced analgesic effects of diode lasers and an LED light source on the dental pulp. Baseline responses to electric pulp testing (EPT) were recorded in 93 healthy unrestored premolar teeth in 26 adults (age range 22–63 years) attending a private dental practice. The teeth were irradiated on buc...

Biofilm-associated infections account for a large proportion of chronic diseases and pose a major health challenge. Metal nanoparticles offer a new way to address this problem, by impairing microbial growth and biofilm formation and by causing degradation of existing biofilms. This review of metal nanoparticles with antimicrobial actions included a...

The effective management of biofilm-associated infections remains a pressing concern in clinical practice, necessitating the development of efficient eradication strategies. This study introduces biotin-modified mesoporous silica nanoparticles (MSN-Biotin) designed to facilitate the delivery of phytochemical agents, including gallic acid and querce...

Tooth color is a major driver of facial esthetics. While permanent changes in tooth shade can be achieved by bleaching and restorations, there is a need for cosmetic products that can cause reversible color changes. This randomized controlled clinical study assessed the effectiveness and safety of a novel color-correcting product (Hismile™ V34 Colo...

Purpose This study aimed to validate qPCR assays for specific microbiota, for use on dental plaque samples stored on Whatman FTA cards to compare relative oral health risk in Rett syndrome. Methods Supragingival dental plaque samples were collected, using a sterile swab, (COPAN FLOQswab™) swabbed onto Whatman FTA™ cards. DNA extraction was perform...

Background Discoloration of carious lesions after application of silver diamine fluoride lowers patient acceptance and limits its wider use for caries arrest. Objective To assess lesion and tooth color changes from 2 novel silver fluoride (AgF) products and its relationship to caries activity (clinical visuo-tactile scores) and bacterial load (usi...

Objectives This laboratory study assessed the performance of a novel fluoride dentifrice containing micro-fibrillated cellulose (MFC) and entrapped silica. Methods Removal of extrinsic stains was assessed using the pellicle cleaning ratio (PCR) method, and radioactive dentin abrasivity (RDA) was measured, to calculate a cleaning efficiency index (...

To investigate the in vitro biocompatibility of human gingival fibroblasts with preformed paediatric crowns and resistance to acid exposure at levels that simulate the oral environment. This laboratory study investigated primary HGFs viability, metabolic activity, cytotoxicity, and apoptotic events on preformed metal crown discs, composite resin-co...

Introduction Diagnostic procedures for pulp vitality assessment are a crucial aspect of routine dental practice. This review aims to provide a comprehensive overview of nontraditional techniques and methodologies for assessing pulp vitality, specifically exploring promising approaches that are currently not used in dental practice. Methods The stu...

Objectives: This study assessed the performance of a novel fluoride dentifrice containing micro- fibrillated cellulose (MFC) and 7% silica (Protegera™) versus common fluoride dentifrices. Methods: Removal of extrinsic stains was assessed using the pellicle cleaning ratio (PCR) method, and radioactive dentin abrasivity (RDA) was measured, to calcula...

Objectives: This study assessed the performance of a novel fluoride dentifrice containing micro- fibrillated cellulose (MFC) and 7% silica (Protegera™) versus common fluoride dentifrices. Methods: Removal of extrinsic stains was assessed using the pellicle cleaning ratio (PCR) method, and radioactive dentin abrasivity (RDA) was measured, to calcula...

Recent advancements in nanotechnology have introduced a myriad of potential applications in dentistry, with nanomaterials playing an increasing role in endodontics. These nanomaterials exhibit distinctive mechanical and chemical properties, rendering them suitable for various dental applications in endodontics, including obturating materials, seale...

Objectives To develop and practically test high‐precision femtosecond laser ablation models for dental hard tissue that are useful for detailed planning of automated laser dental restorative treatment. Methods Analytical models are proposed, derived, and demonstrated for practical calculation of ablation rates, ablation efficiency and ablated morp...

Purpose While silver diamine fluoride has been used extensively for caries arrest and desensitising, silver fluoride (AgF) at neutral pH may also have value as a minimally invasive dental caries treatment. This study explored the effectiveness of two AgF products (AgF/KI and AgF/SnF2) when used in adult patients with special needs (SN) who had high...

Objectives: To investigate knowledge and awareness of dental complications with oral piercings among adults with oral piercings, a control population with no piercings and body-piercing professionals in South-East Queensland, Australia. Methods: Participants recruited from public and private dental clinics and body-piercing professionals from pi...

Endodontics is a technically demanding aspect of dentistry because of the limited ability to see and instrument the root canals of teeth. Conventional endodontic treatment is painstakingly slow, and traditional hand and powered endodontic instruments do not contact all the walls of the root canal. The use of lasers can assist in providing enhanced...

Dentifrice performance in the removal of dental plaque is influenced by the interactions of dentifrice components with tooth surfaces. This randomized controlled clinical study assessed the effectiveness and safety of a novel fluoride dentifrice formulation that included a micro-fibrillated cellulose network with entangled microcrystalline cellulos...

Abstract Background Missed additional canals are a common reason for the failure of root canal treatments. The prevalence of additional canals in molar teeth can vary because of ethnic differences. Hence, this study aimed to determine the prevalence and distribution of middle mesial canals (MMCs) in the second mandibular molars using cone beam comp...

Purpose Pain from musculoskeletal disorders (MSD) is experienced by all types of dental clinicians, leading to forced reduction of work capacity and premature retirement. Prolonged static posture is a major contributor to MSD in dentistry. Currently, there is no uniform ergonomic training in dentistry to prevent MSD. This systematic review explored...

We investigated the effect of femtosecond (fs) laser ablation of enamel and dentin for different pulse wavelengths: infrared (1030 nm), green (515 nm), and ultra-violet (343 nm) and for different pulse separations to determine the optimal irradiation conditions for the precise removal of dental hard tissues with the absence of structural and compos...

Dentifrice performance in the removal of dental plaque is influenced by the interactions of dentifrice components with tooth surfaces. This randomized controlled clinical study assessed the effectiveness and safety of a novel fluoride dentifrice formulation that included a micro-fibrillated cellulose network with entangled microcrystalline cellulos...

Vital pulp therapy (VPT) is primarily intended to preserve the vitality of pulp tissues, which have been exposed for any reason. Various materials and techniques have been proposed to improve treatment outcomes, including the use of lasers. This study aimed to review the histological results of different dental lasers including low-level lasers, ca...

We investigated the effect of femtosecond (fs) laser ablation of enamel and dentin for different pulse wavelengths: infrared (1030 nm), green (515 nm), and ultra-violet (343 nm) and for different pulse separations to determine the optimal irradiation conditions for the precise removal of dental hard tissues with the absence of structural and compos...

Purpose: This systematic review explored dental complications associated with metal ion release from oral piercings using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Methods: Item retrieval from October 2022 to December 2022 from databases, such as Cochrane Central Register of Controlled Trials, Medline, Pu...

We examined the patterns of antibiotic prescribing by medical and non-medical prescribers (dentists, nurse practitioners, and midwives) in Australia. We explored trends in the dispensed use of antibiotics (scripts and defined daily dose [DDD] per 1000 population/day) by Australian prescribers over the 12-year period, 2005-2016. We obtained data on...

Objectives: To investigate the in vitro biocompatibility of human gingival fibroblasts (HGFs) with PPC, and resistance to acid exposure at levels that simulate the oral environment. Materials and Methods: This laboratory study investigated primary HGFs viability, metabolic activity, cytotoxicity, and apoptotic events on preformed metal crown (PMC)...

Nanoparticles can play valuable roles in delivering nucleic acids, including microRNAs (miRNA), which are small, non-coding RNA segments. In this way, nanoparticles may exert post-transcriptional regulatory influences on various inflammatory conditions and bone disorders. This study used biocompatible, core–cone-structured, mesoporous silica nanopa...

Background: This study aimed to determine whether oral health services provision by a dental student clinical outplacement embedded within a Community Controlled Health Service positively impacted a rural Indigenous community and to explore the nature of these benefits. Methods: Aggregated and de-identified 2017, 2018 and 2019 student-led clinic...

Introduction To achieve successful root canal treatments on cardiovascular patients, endodontists must have enough knowledge of these diseases and related considerations. Hence, the aim of this study was to evaluate the knowledge, attitudes, and performance of Iranian endodontists regarding patients with cardiovascular disorders. Materials and Met...

Objectives: This study aimed to assess dentists' attitudes toward providing dental care for older adults with disabilities in Singapore and the factors influencing their willingness to provide care. Background: Dentists face a rapidly ageing patient demographic. Practitioner unwillingness to circumvent the attending challenges of care provision...

Objectives: This laboratory-based study measured ion release from metallic piercings when exposed to organic acids (lactic, citric) and inorganic acids (phosphoric, hydrochloric) that could be encountered in the oral cavity. Methods: Barbell and ring oral piercings composed of stainless steel, titanium or gold-plated titanium were submerged in 2...

Introduction: Oral health therapists (OHTs) are a valuable resource for increasing access to dental care for the frail elderly in nursing homes (NHs). However, OHTs face several barriers and their skill-set continues to be under-utilized. Aims: To evaluate the perceptions of OHTs regarding the barriers towards oral care provision for the elderly...

Background: To evaluate the cyclic fatigue resistance of rotary endodontic nickel-titanium instruments using both experimental and finite element methods. Methodology: Four different proprietary rotary endodontic instruments (PTG, PTU, VB, and TRN) were subjected to cyclic fatigue tests through a custom-built fixture (n = 30 for each group) and tes...

Topical cariostatic agents have become a reasonable alternative for managing dental caries in young children. Silver diamine fluoride (SDF) is a practical topical approach to arrest caries and avoid extensive and risky dental treatment. However, the literature demonstrates a parental hesitation towards accepting SDF because of black unaesthetic too...

Purpose: The aim of this study was to evaluate the influence of luminosity values and smear layer on transmission characteristics of 810 nm near infrared laser energy through dentine, using extracted human teeth. Methods: A total of 200 teeth treated with endodontic medicaments to cause discolouration (Ledermix, Doxypaste or Odontopaste) were se...

Knowledge, attitudes and performance of Iranian endodontists regarding patients with kidney diseases Fatemeh Arabpour1, Maryam Kuzekanani2, Laurence Walsh3, Moghaddameh Mirzaei4 1Department of Orthodontics, School of dentistry, Shahid Sadoughi university of medical sciences, Yazd, Iran 2Department of Endodontics.Kerman university of medical science...

Objective: The high prevalence of chronic kidney disease in the community, especially in older patients,makes their management an important aspect of clinical practice. The aim of this study was to evaluatethe knowledge attitudes and performance of Iranian endodontists regarding patients with chronic kidneydisease (CKD).Methods: This cross-sectiona...

Objective: The purpose of this study was to explore the benefits of a partnership between a university dental school and a Community Controlled Health Service, specifically in relation to improving the oral health of an underserved rural Indigenous community. We sought community opinions on health and social outcomes arising from the service provi...

This study aimed to evaluate and compare the effects of ambient temperature and post-manufacture heat-treatment on the mechanical behavior of nickel-titanium (NiTi) wires. Four types of commercial NiTi variants (Stock NiTi, heat treated “Blue”, “Gold”, “Superflex”, all Dentsply Maillefer, Ballaigues, Switzerland) were stressed in a tensile testing...

Objective To assess literature for the effectiveness and impact of femtosecond (fs) laser irradiation for surface processing of enamel and dentine. Materials and methods This systematic review followed PRISMA guidelines. Criteria for inclusion and exclusion were established, and searches undertaken in the PubMed/MEDLINE, Embase and, Scopus databas...

Micro-ribonucleic acid (miRNA)-based therapies show advantages for bone regeneration but need efficient intracellular delivery methods. Inorganic nanoparticles such as mesoporous bioactive glass nanoparticles (MBGN) and mesoporous silica nanoparticles (MSN) have received growing interest in the intracellular delivery of nucleic acids. This study ex...

Despite the many treatment modalities offered to prevent or manage peri-implantitis, there is currently a lack of high-quality evidence that supports any approach being regarded as a gold standard. Given that methods such as hand scaling with metal instruments and ultrasonic scaling may damage the implant surfaces, it is important to identify metho...

Introduction: Oral health therapists (OHTs) have the potential to increase the access to oral care for elderly residents in nursing homes (NHs). Aims: To evaluate the perceptions of NH staff and OHTs regarding the barriers and enablers toward oral care provision for elderly NH residents, and their perceptions toward interprofessional collaborati...

Objectives: Debridement methods may damage implant surfaces. This in vitro study investigated 8 debridement protocols across three implant surfaces to assess both biofilm removal and surface alterations. Material and methods: 160 commercially pure titanium disks were treated to simulate commercially available titanium implant surfaces- smooth, a...

High fluence focused femtosecond laser pulses were used to perform fast, high precision and minimally damaging cavity cutting of teeth at room temperature without using any irrigation or cooling system. The optimal ablation rates were established for both enamel and dentin, and the surfaces were assessed with optical and scanning electron microscop...

By leveraging ultrashort pulse laser and micro-electromechanical systems (MEMS) technologies, we are developing a miniaturized intraoral dental robotic device that clamps onto teeth, is remotely controlled, and equipped with a focusing and scanning system to perform efficient, fast, and ultra-precise laser treatments of teeth and dental restorative...

Background: This prospective cohort study aimed to evaluate the antibody responses in non-invasive gingival crevicular fluid (GCF) and unstimulated whole saliva to the SARS-CoV-2 Spike unit 1 receptor-binding domain (S1-RBD) protein following administration of the mRNA BNT162b2 vaccine. Materials and methods: This longitudinal study recruited 37...

Following the global COVID-19 pandemic, nanotechnology has been at the forefront and enables the fast development of diagnostic tools, vaccines and anti-viral treatment for this novel virus (SARS-CoV-19). In this review, we first summarize the nanotechnology for the detection of SARS-CoV-2 including nanoparticle-based techniques such as rapid antig...

The development of protocols for laser-assisted therapy demands strict compliance with comprehensive operating parametry. The purpose of this investigation was to examine the accuracy of correlation between laser control panel and fibre emission power values in a selection of diode dental lasers. Through retrospective analysis using successive syst...

The internal topography of the root canal is complex, especially for the mesial root of the permanent first molar. In response to such challenges, enhanced irrigation protocols have been developed, using laser pulses to agitate fluids and enhance the removal of microbial deposits. The aim of this laboratory study was to assess the effectiveness of...

Purpose A systematic review was conducted into paediatric crown decontamination practices using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Method After database retrieval using predefined search terms, two reviewers independently applied the selection criteria, extracted the data, and assessed for risk of bi...

Objectives This study evaluated particle spread associated with various common periodontal aerosol-generating procedures (AGPs) in simulated and clinical settings. Materials and methods A simulation study visualized the aerosols, droplets, and splatter spread with and without high-volume suction (HVS, 325 L/min) during common dental AGPs, namely u...

Intellectual and developmental disabilities are heterogeneous in aetiology and presentation, and one cannot make assumptions about the oral health barriers of those with Rett syndrome (RTT) based on findings from generic studies. This study investigated caregivers’ perceptions regarding access to dental care for those with (RTT), and associations o...

Background Laser-fluorescence diagnostic technology for real-time clinical assessment of residual bacteria could help assist in determining the endpoints for root canal debridement. Sodium hypochlorite (NaOCl) can however quench fluorescence and lead to false low reading. This study aims to evaluate various antioxidant for their ability to recover...

As a range of materials used in endodontics may cause tooth discolouration, exploration of factors responsible for the darkening of the tooth crown or root is warranted. This narrative review paper discusses the range of technical factors that apply in laboratory studies that assess endodontic discolouration. As an example of how these factors oper...

Background Postoperative acute kidney injury (AKI) is a common complication of major gastrointestinal surgery with an impact on short- and long-term survival. No validated system for risk stratification exists for this patient group. This study aimed to validate externally a prognostic model for AKI after major gastrointestinal surgery in two multi...

Subsurface remineralization can be promoted by the topical application of nanoparticles of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP). To assess changes in enamel white spot lesions, an in situ proof-of-concept investigation was performed using 5 subjects (all of whom were healthy young adults) with a cross-over study design. Custo...

Recent studies have shown prebiotic effects of casein phosphopeptides on dental plaque microflora in orthodontic patients. The aim of this study was to assess dental plaque ecological changes in orthodontic patients that resulted from the application of a topical crème containing casein phosphopeptides and 900 ppm fluoride (GC Tooth Mousse Plus™) (...

This study examined the effect of various root canal irrigants and medicaments on dentin fluorescence elicited by 655nm visible red laser light. To replicate clinical use, irrigants were applied onto dentin samples for 2 minutes, while medicaments were applied for 2 weeks. Fluorescence values tracked from baseline across the following to 24 hours,...

Background COVID-19 is a global health crisis. Close contact with the mucous membranes and respiratory secretions of patients and aerosol-generating procedures renders dentists and other oral health professionals at high risk of exposure to SARS-CoV-2. We examined dentists’ knowledge, preparedness, and experiences of managing COVID-19 in Australia....

Objectives: Workplace non-sharps injuries are a common occurrence in a dental school setting. In dentistry, the importance of preventing non-sharps injuries is often overlooked due to emphasis on sharps-related injuries. The aim of this research was to analyse the incidences of non-sharps injuries over an 11-year period in a dental school to ident...

Purpose: This in vitro study compared root canal preparation in curved mesiobuccal canals of molar teeth using either the One Shape™ or the Neoniti (Neolix) rotary NiTi single-file systems, assessing canal transportation, instrument separation and time required for preparation. Methods. Extracted maxillary and mandibular human molar teeth with mes...

Peri-implantitis is the major cause of the failure of dental implants. Since dental implants have become one of the main therapies for teeth loss, the number of patients with peri-implant diseases has been rising. Like the periodontal diseases that affect the supporting tissues of the teeth, peri-implant diseases are also associated with the format...

Aim This study aimed to identify indications for dental treatment under general anaesthetic (GA) and conscious sedation for adult patients with special needs in public dental clinics and recommend pathways to provide safe and effective care. Materials and Methods Following ethics approval from relevant institutions (Approval No: EC00172; Reference...

Background Preformed crowns (PCs) are exposed to potentially infectious bodily fluids during the trial fit, however if they can be safely re-used remains uncertain. This study determined the effects of decontamination methods on various PCs. The key criteria examined were aesthetic, morphological, and elemental characteristics. Design It is a lab-...

Finite element analysis has been a valuable research tool for rotary nickel-titanium endodontic files over the last two decades. This review aims to summarise and critique the methodology as used in currently available endodontic literature for finite element analysis of rotary nickel-titanium instruments. An electronic literature research in PubMe...

PurposeUsing software for assessment of restorative work on typodonts in the simulation laboratory may enhance the objective evaluation of student work. The study aimed to evaluate the inter-rater and intra-rater reliability using 3-D scans from the Planmeca Emerald™ intra-oral scanner with Romexis Compare® software for assessing preparations for p...

Background There is a dearth of literature available on the comparative oral health status of those with Rett syndrome (RTT) despite diurnal bruxism being a supportive diagnostic criterion for the disorder. This study was designed to investigate the dental experiences of individuals with RTT in terms of perceived at-home and professional dental car...

Introduction : This study aimed to assess changes in the fluorescence characteristics of Enterococcus faecalis in human dentine over a period of 24 hours following treatment with endodontic irrigants. Method : Sterilised, non-functional extracted third molars were embedded in acrylic resin and uniformly sectioned into 2mm thick dentine sections. A...