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Khurshid Z, Adanir N, Ratnayake J, Dias G, Cooper PR. Demineralized dentin matrix for bone regeneration in dentistry: A critical update. Saudi Dent J 2024; 36:443-450. [PMID: 38525180 PMCID: PMC10960104 DOI: 10.1016/j.sdentj.2023.11.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/26/2023] [Accepted: 11/26/2023] [Indexed: 03/26/2024] Open
Abstract
Over the last few decades, several new materials and techniques have been developed for bone regeneration. Scaffolds based on demineralized dentin matrix (DDM) present an attractive option due to their availability and several animal and human studies have been conducted to ascertain their utility in regenerative dentistry. The aim of this review was to summarize the recent studies conducted on DDM and used for bone grafts. PubMed, Web of Science, and Scopus were used to search for studies published within the last 10 years. The keywords and terms used were: "demineralized dentine matrix", "bone grafting", "bone augmentation" and "guided tissue regeneration" in various combinations. Original studies (in vitro, animal and human) and systematic reviews were included in the literature search. The literature search initially identified 23 studies (16 animal studies and 7 clinical reports. Most studies included in this review indicate that DDM has demonstrated promising results in a variety of dental and regenerative medicine applications. Further studies are required to completely comprehend its characteristics and prospective applications. Future studies should also focus on optimizing the processing protocols for the production of DDM-based scaffolds.
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Affiliation(s)
- Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Necdet Adanir
- Department of Restorative Dentistry, College of Dentistry, King Faisal University, Al Ahsa 31982, Saudi Arabia
| | - Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - George Dias
- Department of Anatomy, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Paul R. Cooper
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
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Ratnayake J, Gould M, Ramesh N, Mucalo M, Dias GJ. A Porous Fluoride-Substituted Bovine-Derived Hydroxyapatite Scaffold Constructed for Applications in Bone Tissue Regeneration. Materials (Basel) 2024; 17:1107. [PMID: 38473579 DOI: 10.3390/ma17051107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 02/19/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024]
Abstract
Hydroxyapatite is widely used in bone implantation because of its similar mineral composition to natural bone, allowing it to serve as a biocompatible osteoconductive support. A bovine-derived hydroxyapatite (BHA) scaffold was developed through an array of defatting and deproteinization procedures. The BHA scaffold was substituted with fluoride ions using a modified sol-gel method to produce a bovine-derived fluorapatite (BFA) scaffold. Fourier-transform infrared spectroscopy and X-ray diffraction analysis showed that fluoride ions were successfully substituted into the BHA lattice. According to energy dispersive X-ray analysis, the main inorganic phases contained calcium and phosphorus with a fluoride ratio of ~1-2 wt%. Scanning electron microscopy presented a natural microporous architecture for the BFA scaffold with pore sizes ranging from ~200-600 μm. The BHA scaffold was chemically stable and showed sustained degradation in simulated-body fluid. Young's modulus and yield strength were superior in the BFA scaffold to BHA. In vitro cell culture studies showed that the BFA was biocompatible, supporting the proliferative growth of Saos-2 osteoblast cells and exhibiting osteoinductive features. This unique technique of producing hydroxyapatite from bovine bone with the intent of producing high performance biomedically targeted materials could be used to improve bone repair.
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Affiliation(s)
- Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Maree Gould
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Niranjan Ramesh
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Michael Mucalo
- School of Science, University of Waikato, Hamilton 3216, New Zealand
| | - George J Dias
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
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Yang R, Zhao R, Chaudry F, Wang T, Brunton P, Khurshid Z, Ratnayake J. Modern sedative agents and techniques used in dentistry for patients with special needs: A review. J Taibah Univ Med Sci 2024; 19:153-163. [PMID: 38047240 PMCID: PMC10692720 DOI: 10.1016/j.jtumed.2023.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/24/2023] [Accepted: 10/18/2023] [Indexed: 12/05/2023] Open
Abstract
According to the World Health Organisation, approximately 1.3 billion people worldwide experience substantial disability due to physical, mental or sensory impairment. People with special needs require special consideration and more time or altered delivery methods when receiving dental treatments. Various factors, such as patients' lack of cooperation, cognitive impairment and complex medical status, may lead dental practitioners to recommend conscious sedation. Several pharmacological agents and administrative routes are available, which achieve varying levels of sedation ranging from minimal to deep. Pre-operative assessment and careful case selection are necessary to determine the appropriate sedative agent, route of administration and level of sedation for each patient. Thus, a thorough understanding of the pharmacokinetics, risks and benefits, and implications of various sedatives available for PSN is essential to achieve the desired clinical outcomes. This review critically presents the considerations associated with the use of various sedative agents for PSN in dentistry. Considerations include patients' pre-anaesthesia medical comorbidities, cardiorespiratory adverse effects and cooperativeness, and the viable alternative treatment modalities.
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Affiliation(s)
- Ruijia Yang
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Rusin Zhao
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Fatima Chaudry
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Tao Wang
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Paul Brunton
- Department of Prosthodontics and Dental Implantology, Curtin University, Bentley, Australia
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa, KSA
| | - Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
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Choudhury M, Brunton P, Schwass D, Pletzer D, Ratnayake J, Dias G, Tompkins G. Effectiveness of gold nanoparticles in prevention and treatment of oral mucositis in animal models: a systematic review. Syst Rev 2024; 13:39. [PMID: 38273391 PMCID: PMC10809540 DOI: 10.1186/s13643-023-02425-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 12/08/2023] [Indexed: 01/27/2024] Open
Abstract
BACKGROUND Oral mucositis remains a significant complication during cancer therapy with no effective treatment. Gold nanoparticles offer anti-inflammatory, antioxidant properties with low toxicity. This study systematically reviews the literature assessing gold nanoparticles in the management of oral mucositis in animal models. METHODS A literature search was undertaken using MEDLINE, Embase, PubMed, and Web of Science databases, using the format for Systematic Review Centre for Laboratory Animal Experimentation. Prior to the review, the protocol was registered in the systematic review register, PROSPERO (registration no. CRD42021272169). Outcome measures included ulceration, histopathological scores, inflammatory mediators, microbial growth, and pain. Study quality was analysed by SYRCLE risk-of-bias tool. RESULTS Only one study met the inclusion criteria, documenting reduction in ulceration, inflammatory, and oxidative biomarkers. Exposure to AuNPs prevented inflammatory response induced by 5-fluorouracil in oral mucosa of hamsters. However, a high risk of bias necessitates further research. CONCLUSION This review identifies a potential therapeutic strategy for prevention and management of oral mucositis. It also provides future direction for gold nanoparticle research in oral mucositis; however, there is lack of sufficient evidence to derive any conclusion. Research with standardized parameters including nanoparticle size, capping agent, surface charge, and appropriate oral mucositis animal models will establish risk-benefit balance and margin of safety for therapeutic use of gold nanoparticles for oral mucositis.
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Affiliation(s)
- Minati Choudhury
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
- Restorative Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia.
| | - Paul Brunton
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
- DVCA, Curtin University, Perth, Australia
| | - Donald Schwass
- Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Daniel Pletzer
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand.
| | - Jithendra Ratnayake
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - George Dias
- Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - Geoffrey Tompkins
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
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Jum'ah A, Kothari S, Gray AR, Ratnayake J, Leov F, Lyons K, Brunton PA. A randomized clinical trial investigating the effect of three vital tooth bleaching protocols on oral health-related quality of life. Saudi Dent J 2024; 36:77-83. [PMID: 38375377 PMCID: PMC10874788 DOI: 10.1016/j.sdentj.2023.09.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 02/21/2024] Open
Abstract
Objectives This study aimed to compare changes in oral health-related quality of life (OHRQoL) resulting from three vital tooth bleaching protocols. Methods The participants (n = 105) were randomly assigned to one of three vital bleaching treatment groups: home bleaching (HB), in-office bleaching (IOB), or combined bleaching (CB). HB involved the use of custom-made trays and 10% carbamide peroxide for a 14-day treatment period. IOB utilized 37.5% hydrogen peroxide applied in three cycles. CB treatment involved the use of IOB followed by HB. Tooth colour change was evaluated using a shade guide (ΔVS) and a digital spectrophotometry device (ΔES). The Oral Health Impact Profile-14 (OHIP-14) and Oral Impact on Daily Performance-22 (OIDP-22) instruments were used to assess changes in OHRQoL at baseline, 15-days and 6-month recalls. Linear mixed models were used to estimate between- and within-group differences. Results All bleaching protocols led to significant improvements in overall OHIP-14 scores at the 6-month recall (p ≤ 0.037). CB and IOB treatments were associated with more substantial positive impacts on overall scores, psychological discomfort, physical disability (CB only), and psychological disability (CB only) compared to HB (p ≤ 0.011). Significant enhancements in OIDP-22 scores were observed in the CB and HB groups at the 6-month recall compared to baseline (p ≤ 0.006), with evidence indicating that these improvements were greater in the CB group compared to the IOB group (p = 0.007). Conclusion All bleaching treatments demonstrated a positive impact on OHRQoL. However, the positive impact was most consistent across domains and age groups in the CB group. The positive impact was less pronounced in older age groups.
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Affiliation(s)
- Ahmad Jum'ah
- Jordan University of Science and Technology, Faculty of Dentistry, Department of Conservative Dentistry, Irbid 22110, Jordan
| | - Siddharth Kothari
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Andrew R. Gray
- University of Otago, Biostatistics Centre, Division of Health Sciences, 310 Great King Street, Dunedin 9016, New Zealand
| | - Jithendra Ratnayake
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Felicity Leov
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Karl Lyons
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Paul A. Brunton
- Curtin University, Kent Street, Bentley, Western Australia 6102, Australia
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Talesara V, Bennani V, Aarts J, Ratnayake J, Khurshid Z, Brunton P. Accuracy of digitally coded healing abutments: A systematic review. Saudi Dent J 2023; 35:891-903. [PMID: 38107040 PMCID: PMC10724348 DOI: 10.1016/j.sdentj.2023.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 08/10/2023] [Accepted: 08/13/2023] [Indexed: 12/19/2023] Open
Abstract
The aim of this systematic review was to evaluate the in vitro accuracy of dental implant impressions taken using digitally coded healing abutments (CHAs) compared with impressions taken with conventional techniques (CI) and/or within the CHA group at varying degrees of angulations for multiple implant units. Two independent reviewers conducted a systematic electronic search in the MedLine, PubMed, Google Scholar, Cochrane Library, Web of Science, and Scopus databases. Some of the employed key terms, combined with the help of Boolean operators, were: "digitally coded healing abutments", "encode healing abutment", "dental implants", "impression accuracy", "digital impression", and "conventional impression". Publication dates ranged from January 2010 to November 2022. A total of 7 articles fulfilled the inclusion criteria: 6 studies compared the accuracy of CHA with conventional pick-up impression techniques, and one study only used CHAs at different angulations and heights to compare accuracy within the group. The results were divided into Group A (elastomeric impression of CHA) and Group B (CHA + Intraoral scanner). According to the results of this systematic review, elastomeric impression of CHA performed poorly when compared to CI for multiple implants, although an intraoral scan of CHA appears to be more accurate. Within the CHA group, the angulation and visible height of CHA play a significant role in impression accuracy. However, more studies are needed before CHA can be recommended for all non-parallel multiple implant-supported restorations.
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Affiliation(s)
- Vaibhav Talesara
- Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Vincent Bennani
- Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - John Aarts
- Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Saudi Arabia
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Lin J, Bennani V, Aarts JM, Brunton P, Ratnayake J. Factors influencing success rate of ceramic veneers on endodontically treated anterior teeth: A systematic review. J Prosthet Dent 2023:S0022-3913(23)00716-3. [PMID: 38030544 DOI: 10.1016/j.prosdent.2023.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 10/29/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023]
Abstract
STATEMENT OF PROBLEM More conservative restorative approaches have been advocated for nonvital anterior teeth as an alternative to complete coverage crowns to maximize the preservation of tooth structure. Systematic reviews that investigated factors influencing the success rate of porcelain veneers on endodontically treated anterior teeth are lacking. PURPOSE The purpose of this systematic review was to investigate factors influencing the success rate of porcelain veneers on endodontically treated anterior teeth. MATERIAL AND METHODS Searches were performed across Medline/PubMed, Google Scholar, Scopus, and Web of Science electronic databases. In addition, articles were hand searched from references of systematic reviews concerning porcelain veneers and endodontically treated teeth. RESULTS After screening and applying the eligibility, inclusion, and exclusion criteria, 7 articles met the inclusion criteria. Factors that could positively influence the success rate of endodontically treated anterior veneered teeth were immediate dentin sealing, labially positioning of the endodontic access cavity, and incorporating fiber posts. CONCLUSIONS The use of fiber posts and labial positioning of the endodontic access cavity could positively influence the success rate of porcelain veneers on endodontically treated teeth. The effect of immediate dentin sealing on the survival rate of endodontically treated veneered teeth is still unclear and further research is needed.
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Affiliation(s)
- Jacy Lin
- Master's student, Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Vincent Bennani
- Associate Professor, Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - John M Aarts
- Senior Lecturer, Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Paul Brunton
- Deputy Vice-Chancellor Academic, Curtin University, Perth, Australia
| | - Jithendra Ratnayake
- Senior Lecturer, Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
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Khurshid Z, Alfarhan MFA, Bayan Y, Mazher J, Adanir N, Dias GJ, Cooper PR, Ratnayake J. Development, physicochemical characterization and in-vitro biocompatibility study of dromedary camel dentine derived hydroxyapatite for bone repair. PeerJ 2023; 11:e15711. [PMID: 37551347 PMCID: PMC10404400 DOI: 10.7717/peerj.15711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 06/15/2023] [Indexed: 08/09/2023] Open
Abstract
This study aimed to produce hydroxyapatite from the dentine portion of camel teeth using a defatting and deproteinizing procedure and characterize its physicochemical and biocompatibility properties. Biowaste such as waste camel teeth is a valuable source of hydroxyapatite, the main inorganic constituent of human bone and teeth which is frequently used as bone grafts in the biomedical field. Fourier Transform infrared (FTIR), and micro-Raman spectroscopy confirmed the functional groups as-sociated with hydroxyapatite. X-ray diffraction (XRD) studies showed camel dentine-derived hydroxyapatite (CDHA) corresponded with hydroxyapatite spectra. Scanning electron micros-copy (SEM) demonstrated the presence of dentinal tubules measuring from 1.69-2.91 µm. The inorganic phases of CDHA were primarily constituted of calcium and phosphorus, with trace levels of sodium, magnesium, potassium, and strontium, according to energy dispersive X-ray analysis (EDX) and inductively coupled plasma mass spectrometry (ICP-MS). After 28 days of incubation in simulated body fluid (SBF), the pH of the CDHA scaffold elevated to 9.2. in-vitro biocompatibility studies showed that the CDHA enabled Saos-2 cells to proliferate and express the bone marker osteonectin after 14 days of culture. For applications such as bone augmentation and filling bone gaps, CDHA offers a promising material. However, to evaluate the clinical feasibility of the CDHA, further in-vivo studies are required.
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Affiliation(s)
- Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa, Saudi Arabia
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | | | - Yasmin Bayan
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Javed Mazher
- Department of Physics, College of Science, King Faisal University, Al-Ahsa, Saudi Arabia
| | - Necdet Adanir
- Department of Restorative Dentistry, College of Dentistry, King Faisal University, Al-Ahsa, Saudi Arabia
| | - George J. Dias
- Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - Paul R. Cooper
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
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Ahmed H, Ratnayake J, Cathro P, Chandler N. The effect of an additional application of sealer prior to backfilling in the Continuous Wave of Condensation technique. AUST ENDOD J 2023; 49:344-350. [PMID: 35834235 DOI: 10.1111/aej.12658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 06/30/2022] [Accepted: 07/04/2022] [Indexed: 11/29/2022]
Abstract
An additional sealer application was investigated prior to backfilling with the Continuous Wave of Condensation (CWC). 105 Palatal roots were sectioned and prepared to a file size 40, 0.06 taper with Vortex Blue® files. Groups A, B and C had a single sealer application before while groups D, E and F, received a second application of dyed sealer prior to backfilling. Roots were sectioned at 2,3,4,6,7 and 8 mm from the root apex. The percentage of sealer and dentinal tubular penetration depth was calculated at each level. At each ascending level, the sealer percentage decreased for each experimental group while the number of outer third penetration depths increased when all groups were combined. An additional sealer application prior to backfilling had minimal effect on the percentage of sealer or outer third penetration depths and can be considered a clinical preference rather than an imperative step with the CWC technique.
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Affiliation(s)
- Humza Ahmed
- Department of Oral Rehabilitation, University of Otago School of Dentistry, Dunedin, New Zealand
| | - Jithendra Ratnayake
- Department of Oral Sciences, University of Otago School of Dentistry, Dunedin, New Zealand
| | - Peter Cathro
- Department of Oral Rehabilitation, University of Otago School of Dentistry, Dunedin, New Zealand
- Department of Oral Sciences, University of Otago School of Dentistry, Dunedin, New Zealand
| | - Nick Chandler
- Department of Oral Rehabilitation, University of Otago School of Dentistry, Dunedin, New Zealand
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Cathro P, Smith M, Ratnayake J, Heithersay G. Micro-CT Evaluation of Spontaneous Apexification of an Immature Tooth following Trauma. Case Rep Dent 2023; 2023:3779225. [PMID: 37448878 PMCID: PMC10338130 DOI: 10.1155/2023/3779225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
This case reports on the micro-computerised tomography (CT) images of a periapical calcified dome following spontaneous apexification as a subsequence of trauma. An immature, maxillary central incisor was found to be non-vital one month following trauma. The tooth had minimal signs of structural damage; however, there was radiographic evidence of spontaneous apexification. The tooth suffered a second traumatic episode two years later and was decoronated to facilitate bone retention during osseous development. The patient presented with swelling and pain 36 months later, and the tooth root was extracted. The root was embedded in resin, and cross-sectional images were obtained using micro-CT. Analysis of the images provided insight into the structure of the calcified dome that formed following the first traumatic injury.
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Affiliation(s)
- Peter Cathro
- Faculty of Dentistry, The University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Mike Smith
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide SA, Australia
| | - Jithendra Ratnayake
- Faculty of Dentistry, The University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Geoffrey Heithersay
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide SA, Australia
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Khashashneh M, Ratnayake J, Choi JJE, Mei L, Lyons K, Brunton P. The Effect of 10% Carbamide Peroxide Dental Bleaching on the Physical Properties of Invisalign Aligners: An In Vitro Study. Materials (Basel) 2023; 16:ma16114125. [PMID: 37297258 DOI: 10.3390/ma16114125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/16/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023]
Abstract
The high aesthetic demands of patients have increased their requests to align their teeth using clear aligners, including Invisalign. Patients also want to have their teeth whitened for the same purpose; the use of Invisalign as a bleaching tray at night has been reported in few studies. However, whether 10% carbamide peroxide affects the physical properties of Invisalign is unknown. Therefore, the objective of this study was to evaluate the effect of 10% carbamide peroxide on the physical properties of Invisalign when used as a bleaching tray at night. Twenty-two unused Invisalign aligners (Santa Clara, CA, USA) were used to prepare 144 specimens to test their tensile strength, hardness, surface roughness, and translucency. The specimens were divided into four groups: a testing group at baseline (TG1), a testing group after application of bleaching material at 37 °C for 2 weeks (TG2), a control group at baseline (CG1), and a control group after immersion in distilled water at 37 °C for 2 weeks (CG2). Statistical analysis was conducted using a paired t-test, Wilcoxon signed rank test, independent samples t-test, and Mann-Whitney test to compare samples in CG2 to CG1, TG2 to TG1, and TG2 to CG2. Statistical analysis showed no statistically significant difference between the groups for all physical properties, except for hardness (p-value < 0.001) and surface roughness (p-value = 0.007 and p-value < 0.001 for the internal and external surface roughness, respectively), which revealed a reduction in hardness values (from 4.43 ± 0.86 N/mm2 to 2.2 ± 0.29 N/mm2) and an increase in surface roughness (from 1.6 ± 0.32 Ra to 1.93 ± 0.28 Ra and from 0.58 ± 0.12 Ra to 0.68 ± 0.13 Ra for the internal and external surface roughness, respectively) after 2 weeks of dental bleaching. Results showed that Invisalign can be used for dental bleaching without excessive distortion or degradation of the aligner material. However, future clinical trials are required to further assess the feasibility of using Invisalign for dental bleaching.
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Affiliation(s)
- Majd Khashashneh
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- Faculty of Dentistry, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
| | - Jithendra Ratnayake
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Joanne Jung Eun Choi
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Li Mei
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Karl Lyons
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Paul Brunton
- DVCA, Curtin Perth, Curtin University, Bentley, WA 6102, Australia
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Mansoor A, Khurshid Z, Mansoor E, Khan MT, Ratnayake J, Jamal A. Correction: Mansoor et al. Effect of Currently Available Nanoparticle Synthesis Routes on Their Biocompatibility with Fibroblast Cell Lines. Molecules 2022, 27, 6972. Molecules 2023; 28:molecules28104173. [PMID: 37241996 DOI: 10.3390/molecules28104173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 03/28/2023] [Indexed: 05/28/2023] Open
Abstract
The authors wish to make the following correction to this paper [...].
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Affiliation(s)
- Afsheen Mansoor
- Department of Dental Material Sciences, School of Dentistry, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad 45320, Pakistan
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Emaan Mansoor
- Islamic International Dental College, Riphah International University, Islamabad 6000, Pakistan
| | - Muhammad Talal Khan
- Department of Dental Biomaterials, Bakhtawar Amin Medical and Dental Collage, Multan 60650, Pakistan
| | - Jithendra Ratnayake
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Asif Jamal
- Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
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Imran E, Cooper PR, Ratnayake J, Ekambaram M, Mei ML. Potential Beneficial Effects of Hydroxyapatite Nanoparticles on Caries Lesions In Vitro-A Review of the Literature. Dent J (Basel) 2023; 11:dj11020040. [PMID: 36826185 PMCID: PMC9955150 DOI: 10.3390/dj11020040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Dental caries is one of the most common human diseases which can occur in both primary and permanent dentitions throughout the life of an individual. Hydroxyapatite is the major inorganic component of human teeth, consequently, nanosized hydroxyapatite (nHAP) has recently attracted researchers' attention due to its unique properties and potential for caries management. This article provides a contemporary review of the potential beneficial effects of nHAP on caries lesions demonstrated in in vitro studies. Data showed that nHAP has potential to promote mineralization in initial caries, by being incorporated into the porous tooth structure, which resulted from the caries process, and subsequently increased mineral content and hardness. Notably, it is the particle size of nHAP which plays an important role in the mineralization process. Antimicrobial effects of nHAP can also be achieved by metal substitution in nHAP. Dual action property (mineralizing and antimicrobial) and enhanced chemical stability and bioactivity of nHAP can potentially be obtained using metal-substituted fluorhydroxyapatite nanoparticles. This provides a promising synergistic strategy which should be explored in further clinical research to enable the development of dental therapeutics for use in the treatment and management of caries.
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Affiliation(s)
- Eisha Imran
- Department of Dental Materials, Islamabad Medical and Dental College, Islamabad 44000, Pakistan
| | - Paul R. Cooper
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Correspondence: (P.R.C.); (M.L.M.)
| | - Jithendra Ratnayake
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Manikandan Ekambaram
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - May Lei Mei
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Correspondence: (P.R.C.); (M.L.M.)
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Khurshid Z, Alfarhan MF, Mazher J, Bayan Y, Cooper PR, Dias GJ, Adanir N, Ratnayake J. Extraction of Hydroxyapatite from Camel Bone for Bone Tissue Engineering Application. Molecules 2022; 27:molecules27227946. [PMID: 36432047 PMCID: PMC9695224 DOI: 10.3390/molecules27227946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/04/2022] [Accepted: 11/15/2022] [Indexed: 11/18/2022]
Abstract
Waste tissues such as mammalian bone are a valuable source from which to extract hydroxyapatite. Camel bone-based hydroxyapatite (CBHA) was extracted from the femur of camel bones using a defatting and deproteinization procedure. The extracted CBHA was mechanically, chemically, physically, morphologically and structurally characterized. Fourier-Transform Infra-Red (FTIR) spectra, Micro-Raman, and X-ray diffraction analysis confirmed successful extraction of hydroxyapatite. The mechanical properties of the CBHA scaffold were measured using a Universal Instron compression tester. Scanning electron microscopy showed the presence of a characteristic interconnected porous architecture with pore diameter ranging from 50-600 µm and micro-computer tomography (Micro-CT) analysis identified a mean porosity of 73.93. Thermogravimetric analysis showed that the CBHA was stable up to 1000 °C and lost only 1.435% of its weight. Inductively coupled plasma-mass spectrometry (ICP-MS) and Energy-dispersive-X-ray (EDX) analysis demonstrated the presence of significant amounts of calcium and phosphorus and trace ions of sodium, magnesium, zinc, lead and strontium. Following 21 days of incubation in simulated body fluid (SBF), the pH fluctuated between 10-10.45 and a gradual increase in weight loss was observed. In conclusion, the extracted CBHA is a promising material for future use in bone tissue regeneration applications.
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Affiliation(s)
- Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
- Correspondence: ; Tel.: +966-558420410
| | | | - Javed Mazher
- Department of Physics, College of Science, King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Yasmin Bayan
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Paul R. Cooper
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - George J. Dias
- Department of Anatomy, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Necdet Adanir
- Department of Restorative Dentistry, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
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Cai M, Ratnayake J, Cathro P, Gould M, Ali A. Investigation of a Novel Injectable Chitosan Oligosaccharide-Bovine Hydroxyapatite Hybrid Dental Biocomposite for the Purposes of Conservative Pulp Therapy. Nanomaterials (Basel) 2022; 12:3925. [PMID: 36364700 PMCID: PMC9658921 DOI: 10.3390/nano12213925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 10/31/2022] [Accepted: 11/04/2022] [Indexed: 06/16/2023]
Abstract
This study aimed to develop injectable chitosan oligosaccharide (COS) and bovine hydroxyapatite (BHA) hybrid biocomposites, and characterise their physiochemical properties for use as a dental pulp-capping material. The COS powder was prepared from chitosan through hydrolytic reactions and then dissolved in 0.2% acetic acid to create a solution. BHA was obtained from waste bovine bone and milled to form a powder. The BHA powder was incorporated with the COS solution at different proportions to create the COS-BHA hybrid biocomposite. Zirconium oxide (ZrO2) powder was included in the blend as a radiopacifier. The composite was characterised to evaluate its physiochemical properties, radiopacity, setting time, solubility, and pH. Fourier-transform infrared spectroscopic analysis of the COS-BHA biocomposite shows the characteristic peaks of COS and hydroxyapatite. Compositional analysis via ICP-MS and SEM-EDX shows the predominant elements present to be the constituents of COS, BHA, and ZrO2. The hybrid biocomposite demonstrated an average setting time of 1 h and 10 min and a pH value of 10. The biocomposite demonstrated solubility when placed in a physiological solution. Radiographically, the set hybrid biocomposite appears to be more radiopaque than the commercial mineral trioxide aggregate (MTA). The developed COS-BHA hybrid biocomposite demonstrated good potential as a pulp-capping agent exhibiting high pH, with a greater radiopacity and reduced setting time compared to MTA. Solubility of the biocomposite may be addressed in future studies with the incorporation of a cross-linking agent. However, further in vitro and in vivo studies are necessary to evaluate its clinical feasibility.
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Adanir N, Khurshid Z, Ratnayake J. The Regenerative Potential of Decellularized Dental Pulp Extracellular Matrix: A Systematic Review. Materials (Basel) 2022; 15:6386. [PMID: 36143698 PMCID: PMC9505725 DOI: 10.3390/ma15186386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/06/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
INTRODUCTION The regeneration of dental pulp remains a challenge. Although several treatment modalities have been proposed to promote pulpal regeneration, these treatments have several drawbacks. More recently, decellularized dental pulp extracellular matrix (DP-ECM) has been proposed to regenerate dental pulp. However, to date, no systematic review has summarized the overall outcome and assessed the available literature focusing on the endodontic use of DP-ECM. The aim of this systematic review is to critically appraise the literature, summarize the overall outcomes, and provide clinical recommendations about DP-ECM. METHODOLOGY Following the Participants Intervention Control and Outcomes (PICO) principle, a focused question was constructed before conducting a search of the literature and of electronic research databases and registers. The focused question was: 'Compared to controls, does decellularized dental pulp extracellular matrix (DP-ECM) stimulate the regeneration of dental pulp cells and tissue?' Quality assessment of the studies was carried out using Guidelines for Reporting Pre-Clinical in Vitro Studies on Dental Materials and ARRIVE guidelines. RESULTS 12 studies were included in this review. Data from five in vitro experiments and eight in vivo experiments were extracted and the quality of the experiments was assessed. In majority of the studies, DP-ECM appeared to have stimulated pulpal regeneration. However, several sources of bias and methodological deficiencies were found during the quality assessment. CONCLUSION Within the limitations of this review and the included studies, it may be concluded that there is insufficient evidence to deduce the overall efficacy of DP-ECM for pulpal regeneration. More research, clinical and pre-clinical, is required for more conclusive evidence.
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Affiliation(s)
- Necdet Adanir
- Department of Restorative Dentistry, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Jithendra Ratnayake
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
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Ratnayake J, Veerasamy A, Ahmed H, Coburn D, Loch C, Gray AR, Lyons KM, Heng NCK, Cannon RD, Leung M, Brunton PA. Clinical and Microbiological Evaluation of a Chlorhexidine-Modified Glass Ionomer Cement (GIC-CHX) Restoration Placed Using the Atraumatic Restorative Treatment (ART) Technique. Materials 2022; 15:ma15145044. [PMID: 35888511 PMCID: PMC9320984 DOI: 10.3390/ma15145044] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 12/04/2022]
Abstract
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. The other carious root lesion was restored with the same GIC modified with 5% chlorhexidine digluconate (GIC-CHX; test). Patient acceptability and restoration survival rate were evaluated at baseline and after 6 months. Plaque and saliva samples around the test and control restorations were collected, and microbiological analysis for selected bacterial and fungal viability were completed at baseline, and after 1, 3, and 6 months. In total, 52 restorations were placed using GIC and GIC-CHX in 26 participants; 1 patient was lost to follow-up. After reviewing the restorations during their baseline appointments, participants indicated that they were satisfied with the appearance of the restorations (n = 25, 96%) and did not feel anxious during the procedure (n = 24, 92%). Forty-eight percent (n = 12) of the GIC-CHX restorations were continuous with the existing anatomic form as opposed to six for the GIC restorations (24%), a difference which was statistically significant (p = 0.036). There was no statistically significant reduction in the mean count of the tested microorganisms in plaque samples for either type of restorations after 1, 3, or 6 months. Restoration of carious root surfaces with GIC-CHX resulted in higher survival rates than the control GIC. ART using GIC-CHX may therefore be a viable approach for use in outreach dental services to restore root surface carious lesions where dental services are not readily available, and for older people and special needs groups.
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Affiliation(s)
- Jithendra Ratnayake
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
- Correspondence: ; Tel.: +64-034797355
| | - Arthi Veerasamy
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - Hassan Ahmed
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - David Coburn
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - Carolina Loch
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - Andrew R. Gray
- Biostatistics Centre, Division of Health Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand;
| | - Karl M. Lyons
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - Nicholas C. K. Heng
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - Richard D. Cannon
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
| | - Marcus Leung
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.V.); (H.A.); (D.C.); (C.L.); (K.M.L.); (N.C.K.H.); (R.D.C.); (M.L.)
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Khurshid Z, Asiri FYI, Najeeb S, Ratnayake J. The Impact of Autologous Platelet Concentrates on the Periapical Tissues and Root Development of Replanted Teeth: A Systematic Review. Materials 2022; 15:ma15082776. [PMID: 35454469 PMCID: PMC9031947 DOI: 10.3390/ma15082776] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/06/2022] [Accepted: 04/07/2022] [Indexed: 02/06/2023]
Abstract
Introduction: In many cases, the replanted teeth may undergo resorption or ankyloses. Recent studies show that autologous platelet concentrates (APCs) may improve the outcomes of tooth replantation. The aim of this systematic review was to summarize and critically appraise the currently available literature on the use of APCs before tooth replantation. Methodology: An electronic search was conducted on the following research databases: PubMed/MEDLINE, ISI Web of Science, EMBASE and Scopus. The following medical subject heading (MeSH) keywords used were: ((tooth replantation) OR (replanted tooth) OR (teeth replantation) OR (replanted teeth)) AND ((autologous platelet concentrate) OR (platelet-rich plasma) OR (platelet-rich fibrin) OR (autologous platelet)). The studies’ data was extracted, and the research’ quality was rated using the CARE and ARRIVE protocols. Results: Ten case reports and three animal studies, one cell study and one study, which included both animal and in vitro experiments, were included in this review. In majority of the studies, APCs improved the outcomes of tooth replantation. However, there were various sources of bias in the most of the research, which may have influenced the results. Conclusions: Although majority of the studies indicate that APCs may improve outcomes of tooth replantation, majority of the studies contained numerous sources of bias. Additionally, the sample size of the included subjects is inadequate to predict the clinical efficacy of APCs in management of replanted teeth. Large-scale, multi-center and long-term studies are required to ascertain the efficacy of APCs in improve the outcomes of tooth replantation.
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Affiliation(s)
- Zohaib Khurshid
- Department of Prosthodontics and Dental Materials, School of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
- Correspondence: ; Tel.: +966-558420410
| | - Faris Yahya I. Asiri
- Department of Preventive Dentistry, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Shariq Najeeb
- Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada;
| | - Jithendra Ratnayake
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand;
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Ngah NA, Dias GJ, Tong DC, Mohd Noor SNF, Ratnayake J, Cooper PR, Hussaini HM. Lyophilised Platelet-Rich Fibrin: Physical and Biological Characterisation. Molecules 2021; 26:molecules26237131. [PMID: 34885714 PMCID: PMC8658988 DOI: 10.3390/molecules26237131] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 01/27/2023] Open
Abstract
Background: Platelet-rich fibrin (PRF) has gained popularity in craniofacial surgery, as it provides an excellent reservoir of autologous growth factors (GFs) that are essential for bone regeneration. However, the low elastic modulus, short-term clinical application, poor storage potential and limitations in emergency therapy use restrict its more widespread clinical application. This study fabricates lyophilised PRF (Ly-PRF), evaluates its physical and biological properties, and explores its application for craniofacial tissue engineering purposes. Material and methods: A lyophilisation method was applied, and the outcome was evaluated and compared with traditionally prepared PRF. We investigated how lyophilisation affected PRF’s physical characteristics and biological properties by determining: (1) the physical and morphological architecture of Ly-PRF using SEM, and (2) the kinetic release of PDGF-AB using ELISA. Results: Ly-PRF exhibited a dense and homogeneous interconnected 3D fibrin network. Moreover, clusters of morphologically consistent cells of platelets and leukocytes were apparent within Ly-PRF, along with evidence of PDGF-AB release in accordance with previously reports. Conclusions: The protocol established in this study for Ly-PRF preparation demonstrated versatility, and provides a biomaterial with growth factor release for potential use as a craniofacial bioscaffold.
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Affiliation(s)
- Nurul Aida Ngah
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (D.C.T.); (J.R.); (P.R.C.); (H.M.H.)
- Faculty of Dentistry, Universiti Teknologi MARA, Sungai Buloh Campus, Jalan Hospital, Sungai Buloh 47000, Malaysia
- Correspondence:
| | - George J. Dias
- Department of Anatomy, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand;
| | - Darryl C. Tong
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (D.C.T.); (J.R.); (P.R.C.); (H.M.H.)
| | - Siti Noor Fazliah Mohd Noor
- Craniofacial and Biomaterial Sciences Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas 13200, Malaysia;
| | - Jithendra Ratnayake
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (D.C.T.); (J.R.); (P.R.C.); (H.M.H.)
| | - Paul R. Cooper
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (D.C.T.); (J.R.); (P.R.C.); (H.M.H.)
| | - Haizal Mohd Hussaini
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (D.C.T.); (J.R.); (P.R.C.); (H.M.H.)
- Faculty of Dental Medicine, Kampus A Universitas Airlangga, Surabaya 60132, Indonesia
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Olson H, Ratnayake J, Senthilkumar A, Quaranta A, Meldrum A. Working characteristics for practicing dental hygienists in two countries in different hemispheres. Int J Dent Hyg 2021; 20:209-218. [PMID: 34288413 DOI: 10.1111/idh.12538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 07/13/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVES The study aimed to collect and compare practice characteristics for dental hygienists (DHs) in New Zealand (NZ) and Sweden. METHODS Dental hygienists from NZ and Sweden were invited to participate in an anonymous online survey focusing on their working practices. An email, with a link to the online survey and a participant information sheet, was sent to DHs registered with their professional association in their respective country. Frequency analyses and cross-tabulations were conducted using Chi-square and Fisher's Exact tests to investigate possible statistical associations to allow for comparisons between the countries. RESULTS DH is a female-dominated workforce with equal distribution of gender in both countries. The majority of DHs in NZ worked in private practice while Swedish DHs mostly worked in the public sector. NZ participants were younger and with a more recent qualification than their Swedish counterparts. The highest degree of education was a PhD for DHs working in Sweden, compared with a Masters' Degree for NZ participants. The majority of participants from both countries treated patients 65 years of age or older, with the most common medical conditions being cardiovascular disease and diabetes mellitus. The most common dental condition observed/treated was periodontal disease. Over 60% agreed to have an understanding of information technology (IT). The most used technical equipment was digital radiology, followed by other diagnostic tools. CONCLUSION Findings confirm previous international data on demographical uptake for the DH workforce in NZ and Sweden. A coherence was seen in patient characteristics, DHs attitudes towards information technology and use of technical equipment.
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Affiliation(s)
- Hanna Olson
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Jithendra Ratnayake
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Arthi Senthilkumar
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Alessandro Quaranta
- School of Dentistry and Oral Health, Griffith University, Gold Coast Campus, Queensland, Australia
| | - Alison Meldrum
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
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Brunton PA, Ratnayake J, Bodansky HJ, Mei L, Veerasamy A, Hall R. An intraoral device for weight loss: initial clinical findings. Br Dent J 2021:10.1038/s41415-021-3081-1. [PMID: 34172922 PMCID: PMC8231740 DOI: 10.1038/s41415-021-3081-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 09/24/2020] [Indexed: 12/13/2022]
Abstract
Introduction Obesity is a global epidemic, increasing the risk of many associated health issues.Aim The aim of this clinical study was to investigate the acceptability and tolerability of an intraoral device, designed to facilitate weight loss.Method Seven healthy obese participants were recruited. The device, which incorporated closed-field magnets with keepers to restrict mouth opening, was cemented to the participants' first molars. The participants were given a commercially available liquid diet for two weeks. The comfort and tolerability of the device were assessed using a quality of life questionnaire during review appointments at 1, 7 and 14 days and two weeks after device removal.Results The participants reached a mean weight loss of 6.36 (SD = 3.79) kilograms, which represents approximately 5.1% of their body weight. The participants had trouble pronouncing some words and felt tense and embarrassed 'only occasionally'. The participants 'hardly ever' reported a change in taste sensation or felt uncomfortable drinking. However, participants indicated that they occasionally had discomfort and felt that life in general was less satisfying. Qualitative analysis showed that the participants were happy with the outcome and were motivated to lose more weight.Conclusion The participants tolerated the device for a two-week period with satisfactory weight loss and were further motivated to continue their weight loss journey.
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Affiliation(s)
- Paul A Brunton
- University of Otago, Faculty of Dentistry, 310 Great King Street, North Dunedin 9016, New Zealand.
| | - Jithendra Ratnayake
- University of Otago, Faculty of Dentistry, 310 Great King Street, North Dunedin 9016, New Zealand
| | | | - Li Mei
- University of Otago, Faculty of Dentistry, 310 Great King Street, North Dunedin 9016, New Zealand
| | - Arthi Veerasamy
- University of Otago, Faculty of Dentistry, 310 Great King Street, North Dunedin 9016, New Zealand
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Zhao R, Yang R, Cooper PR, Khurshid Z, Shavandi A, Ratnayake J. Bone Grafts and Substitutes in Dentistry: A Review of Current Trends and Developments. Molecules 2021; 26:3007. [PMID: 34070157 PMCID: PMC8158510 DOI: 10.3390/molecules26103007] [Citation(s) in RCA: 160] [Impact Index Per Article: 53.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/29/2021] [Accepted: 05/13/2021] [Indexed: 02/07/2023] Open
Abstract
After tooth loss, bone resorption is irreversible, leaving the area without adequate bone volume for successful implant treatment. Bone grafting is the only solution to reverse dental bone loss and is a well-accepted procedure required in one in every four dental implants. Research and development in materials, design and fabrication technologies have expanded over the years to achieve successful and long-lasting dental implants for tooth substitution. This review will critically present the various dental bone graft and substitute materials that have been used to achieve a successful dental implant. The article also reviews the properties of dental bone grafts and various dental bone substitutes that have been studied or are currently available commercially. The various classifications of bone grafts and substitutes, including natural and synthetic materials, are critically presented, and available commercial products in each category are discussed. Different bone substitute materials, including metals, ceramics, polymers, or their combinations, and their chemical, physical, and biocompatibility properties are explored. Limitations of the available materials are presented, and areas which require further research and development are highlighted. Tissue engineering hybrid constructions with enhanced bone regeneration ability, such as cell-based or growth factor-based bone substitutes, are discussed as an emerging area of development.
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Affiliation(s)
- Rusin Zhao
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand; (R.Z.); (R.Y.); (P.R.C.)
| | - Ruijia Yang
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand; (R.Z.); (R.Y.); (P.R.C.)
| | - Paul R. Cooper
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand; (R.Z.); (R.Y.); (P.R.C.)
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Amin Shavandi
- BioMatter Unit—École Polytechnique de Bruxelles, Université Libre de Bruxelles (ULB), Avenue F.D. Roosevelt, 50—CP 165/61, 1050 Brussels, Belgium;
| | - Jithendra Ratnayake
- Department of Oral Science, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand; (R.Z.); (R.Y.); (P.R.C.)
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Ngah NA, Ratnayake J, Cooper PR, Dias GJ, Tong DC, Mohd Noor SNF, Hussaini HM. Potential of Lyophilized Platelet Concentrates for Craniofacial Tissue Regenerative Therapies. Molecules 2021; 26:molecules26030517. [PMID: 33498167 PMCID: PMC7863735 DOI: 10.3390/molecules26030517] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/14/2021] [Accepted: 01/14/2021] [Indexed: 01/01/2023] Open
Abstract
Objective: The use of platelet concentrates (PCs) in oral and maxillofacial surgery, periodontology, and craniofacial surgery has been reported. While PCs provide a rich reservoir of autologous bioactive growth factors for tissue regeneration, their drawbacks include lack of utility for long-term application, low elastic modulus and strength, and limited storage capability. These issues restrict their broader application. This review focuses on the lyophilization of PCs (LPCs) and how this processing approach affects their biological and mechanical properties for application as a bioactive scaffold for craniofacial tissue regeneration. Materials and Methods: A comprehensive search of five electronic databases, including Medline, PubMed, EMBASE, Web of Science, and Scopus, was conducted from 1946 until 2019 using a combination of search terms relating to this topic. Results: Ten manuscripts were identified as being relevant. The use of LPCs was mostly studied in in vitro and in vivo craniofacial bone regeneration models. Notably, one clinical study reported the utility of LPCs for guided bone regeneration prior to dental implant placement. Conclusions: Lyophilization can enhance the inherent characteristics of PCs and extends shelf-life, enable their use in emergency surgery, and improve storage and transportation capabilities. In light of this, further preclinical studies and clinical trials are required, as LPCs offer a potential approach for clinical application in craniofacial tissue regeneration.
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Affiliation(s)
- Nurul Aida Ngah
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (N.A.N.); (P.R.C.); (D.C.T.); (H.M.H.)
| | - Jithendra Ratnayake
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (N.A.N.); (P.R.C.); (D.C.T.); (H.M.H.)
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
- Correspondence:
| | - Paul R. Cooper
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (N.A.N.); (P.R.C.); (D.C.T.); (H.M.H.)
| | - George J. Dias
- Department of Anatomy, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand;
| | - Darryl C. Tong
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (N.A.N.); (P.R.C.); (D.C.T.); (H.M.H.)
| | - Siti Noor Fazliah Mohd Noor
- Craniofacial and Biomaterial Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas 13200, Malaysia;
| | - Haizal Mohd Hussaini
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (N.A.N.); (P.R.C.); (D.C.T.); (H.M.H.)
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Oliveira ÉR, Nie L, Podstawczyk D, Allahbakhsh A, Ratnayake J, Brasil DL, Shavandi A. Advances in Growth Factor Delivery for Bone Tissue Engineering. Int J Mol Sci 2021; 22:E903. [PMID: 33477502 PMCID: PMC7831065 DOI: 10.3390/ijms22020903] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 12/17/2022] Open
Abstract
Shortcomings related to the treatment of bone diseases and consequent tissue regeneration such as transplants have been addressed to some extent by tissue engineering and regenerative medicine. Tissue engineering has promoted structures that can simulate the extracellular matrix and are capable of guiding natural bone repair using signaling molecules to promote osteoinduction and angiogenesis essential in the formation of new bone tissues. Although recent studies on developing novel growth factor delivery systems for bone repair have attracted great attention, taking into account the complexity of the extracellular matrix, scaffolding and growth factors should not be explored independently. Consequently, systems that combine both concepts have great potential to promote the effectiveness of bone regeneration methods. In this review, recent developments in bone regeneration that simultaneously consider scaffolding and growth factors are covered in detail. The main emphasis in this overview is on delivery strategies that employ polymer-based scaffolds for spatiotemporal-controlled delivery of both single and multiple growth factors in bone-regeneration approaches. From clinical applications to creating alternative structural materials, bone tissue engineering has been advancing constantly, and it is relevant to regularly update related topics.
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Affiliation(s)
- Érica Resende Oliveira
- Food Engineering Department, School of Agronomy, Universidade Federal de Goiás, Campus Samambaia, Goiânia CEP 74690-900, Goiás, Brazil;
| | - Lei Nie
- College of Life Sciences, Xinyang Normal University, Xinyang 464000, China
| | - Daria Podstawczyk
- Department of Process Engineering and Technology of Polymer and Carbon Materials, Faculty of Chemistry, Wroclaw University of Science and Technology, 4/6 Norwida Street, 50-373 Wroclaw, Poland;
| | - Ahmad Allahbakhsh
- Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran;
| | - Jithendra Ratnayake
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand;
| | - Dandara Lima Brasil
- Food Science Department, Universidade Federal de Lavras, Lavras CEP 37200-900, Minas Gerais, Brazil;
| | - Amin Shavandi
- BioMatter Unit—École Polytechnique de Bruxelles, Université Libre de Bruxelles, Avenue F.D. Roosevelt, 50—CP 165/61, 1050 Brussels, Belgium
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Ratnayake J, Guan G, Polonowita A, Li KC, Gray AR, Waddell JN, Loch C, Brunton PA. Can the Measurement of Jaw-Opening Forces Assist in the Diagnosis of Temporomandibular Disorders? J Oral Facial Pain Headache 2020; 34:199-205. [PMID: 32870948 DOI: 10.11607/ofph.2587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AIMS To investigate the effectiveness of a novel jaw-opening-force measuring device as a screening tool to aid in the diagnosis of temporomandibular disorders (TMD). METHODS Symptomatic TMD patients (n = 58) and control TMD-free participants (n = 56) were screened by an oral medicine specialist according to the Diagnostic Criteria for TMD (DC/TMD). TMD patients were divided into three subcategories based on TMD symptoms (myofascial pain, disc displacement, and both combined). Jaw-opening forces were measured in both groups with an adjustable head device connected to a 1,000-N-load cell. Seven attempts were recorded at 10-second intervals by a data-capturing system. The geometric mean force values were obtained after discarding the first and last attempts. RESULTS TMD-free participants had greater jaw-opening forces than TMD patients both without and with adjustments for age, sex, height, and weight (both P < .001). The geometric mean ± standard deviation values for TMD patients were 18.5 ± 1.62 N and 47.7 ± 1.53 N for TMD-free participants. Differences in jaw-opening forces among the three TMD subcategories were not statistically significant; however, patients with disc displacement (23.7 ± 1.46 N) had greater jaw forces than patients with myofascial pain (17.0 ± 1.74 N) and both myofascial pain and disc displacement (17.0 ± 1.56 N). CONCLUSION This study demonstrated that differences in jaw-opening forces could be used as a diagnostic tool for TMD. Future studies should explore the potential of this device to measure improvement in jaw-opening forces following TMD treatment.
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Hrebien S, Citi V, Garcia-Murillas I, Cutts R, Fenwick K, Kozarewa I, McEwen R, Ratnayake J, Maudsley R, Carr TH, de Bruin EC, Schiavon G, Oliveira M, Turner N. Early ctDNA dynamics as a surrogate for progression-free survival in advanced breast cancer in the BEECH trial. Ann Oncol 2020; 30:945-952. [PMID: 30860573 PMCID: PMC6594458 DOI: 10.1093/annonc/mdz085] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Background Dynamic changes in circulating tumour DNA (ctDNA) levels may predict long-term outcome. We utilised samples from a phase I/II randomised trial (BEECH) to assess ctDNA dynamics as a surrogate for progression-free survival (PFS) and early predictor of drug efficacy. Patients and methods Patients with estrogen receptor-positive advanced metastatic breast cancer (ER+ mBC) in the BEECH study, paclitaxel plus placebo versus paclitaxel plus AKT inhibitor capivasertib, had plasma samples collected for ctDNA analysis at baseline and at multiple time points in the development cohort (safety run-in, part A) and validation cohort (randomised, part B). Baseline sample ctDNA sequencing identified mutations for longitudinal analysis and mutation-specific digital droplet PCR (ddPCR) assays were utilised to assess change in ctDNA abundance (allele fraction) between baseline and 872 on-treatment samples. Primary objective was to assess whether early suppression of ctDNA, based on pre-defined criteria from the development cohort, independently predicted outcome in the validation cohort. Results In the development cohort, suppression of ctDNA was apparent after 8 days of treatment (P = 0.014), with cycle 2 day 1 (4 weeks) identified as the optimal time point to predict PFS from early ctDNA dynamics. In the validation cohort, median PFS was 11.1 months in patients with suppressed ctDNA at 4 weeks and 6.4 months in patients with high ctDNA (hazard ratio = 0.20, 95% confidence interval 0.083–0.50, P < 0.0001). There was no difference in the level of ctDNA suppression between patients randomised to capivasertib or placebo overall (P = 0.904) nor in the PIK3CA mutant subpopulation (P = 0.071). Clonal haematopoiesis of indeterminate potential (CHIP) was evident in 30% (18/59) baseline samples, although CHIP had no effect on tolerance of chemotherapy nor on PFS. Conclusion Early on-treatment ctDNA dynamics are a surrogate for PFS. Dynamic ctDNA assessment has the potential to substantially enhance early drug development. Clinical registration number NCT01625286.
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Affiliation(s)
- S Hrebien
- Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK
| | - V Citi
- Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK; Clinical Pharmacology and Pharmacogenetics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - I Garcia-Murillas
- Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK
| | - R Cutts
- Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK
| | - K Fenwick
- Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK
| | - I Kozarewa
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - R McEwen
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - J Ratnayake
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - R Maudsley
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - T H Carr
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - E C de Bruin
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - G Schiavon
- Oncology, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - M Oliveira
- Vall d'Hebron University Hospital and Vall d'Hebron Institute of Oncology (VHIO), Barcelona, Spain
| | - N Turner
- Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK; Breast Unit, Royal Marsden Hospital, London, UK.
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Sarfaraz S, Shabbir J, Mudasser MA, Khurshid Z, Al-Quraini AAA, Abbasi MS, Ratnayake J, Zafar MS. Knowledge and Attitude of Dental Practitioners Related to Disinfection during the COVID-19 Pandemic. Healthcare (Basel) 2020; 8:E232. [PMID: 32722402 PMCID: PMC7551794 DOI: 10.3390/healthcare8030232] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 07/22/2020] [Accepted: 07/22/2020] [Indexed: 12/27/2022] Open
Abstract
The world is currently facing a pandemic crisis due to a novel coronavirus. For this purpose, acquiring updated knowledge regarding prevention and disinfection during the current pandemic is necessary for every dental practitioner. In our study, we aimed to evaluate globally the level of knowledge and the attitude of dental practitioners related to disinfection. A total of 385 participants out of 401 participants from 23 different countries across the world were included in the final analysis after the exclusion of incomplete responses. The majority of the dentists who responded were females (53.8%) and were practicing at private health institutes (36.4%). The mean knowledge score of the participants was estimated to be 4.19 ± 1.88 out of 12, reflecting insufficient knowledge, and the mean attitude score of the participants was estimated to be 12.24 ± 3.23 out of 15, which shows a positive attitude toward disinfection practices during coronavirus 2019 (COVID-19). Thus, the current study indicated a lack of knowledge in fundamental aspects of disinfection protocols with a significant and positive attitude from dental health professionals toward disinfection regarding the coronavirus 2019 (COVID-19) pandemic.
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Affiliation(s)
- Shaur Sarfaraz
- Institute of Medical Education, Jinnah Sindh Medical University, Karachi 75510, Pakistan;
| | - Juzer Shabbir
- Operative Dentistry Department, Liaquat College of Medicine and Dentistry, Karachi 75290, Pakistan;
| | - Muhammad Adeel Mudasser
- Dr. Ishrat-Ul-Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences (DUHS), Karachi 74200, Pakistan;
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Ahmed Adel A. Al-Quraini
- Department of Dental Hospital, College of Dentistry, King Faisal University, Al-Ahsa 319825, Saudi Arabia;
| | - Maria Shakoor Abbasi
- Department of Prosthodontics, Altamash Institute of Dental Medicine, Karachi 75500, Pakistan;
| | - Jithendra Ratnayake
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand;
| | - Muhammad Sohail Zafar
- Department of Restorative Dentistry, College of Dentistry, Taibah University, Al-Madina Al-Munawwarah 41311, Saudi Arabia;
- Department of Dental Materials, Islamic International Dental College, Riphah International University, Islamabad 44000, Pakistan
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Huang J, Ratnayake J, Ramesh N, Dias GJ. Development and Characterization of a Biocomposite Material from Chitosan and New Zealand-Sourced Bovine-Derived Hydroxyapatite for Bone Regeneration. ACS Omega 2020; 5:16537-16546. [PMID: 32685818 PMCID: PMC7364611 DOI: 10.1021/acsomega.0c01168] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 06/18/2020] [Indexed: 05/09/2023]
Abstract
A biocomposite scaffold was developed using chitosan (CS) and bovine-derived hydroxyapatite (BHA). The prepared CS-BHA biocomposite scaffold was characterized for its physiochemical and biological properties and compared against control BHA scaffolds to evaluate the effects of CS. Energy-dispersive X-ray analysis confirmed the elemental composition of the CS-BHA scaffold, which presented peaks for C and O from CS and Ca and P along with trace elements in the bovine bone such as Na, Mg, and Cl. Fourier transform infrared spectroscopy confirmed the presence of phosphate, hydroxyl, carbonate, and amide functional groups attributed to the CS and BHA present in the biocomposite scaffolds. The CS-BHA scaffolds demonstrated an interconnected porous structure with pore sizes ranging from 60 to 600 μm and a total porosity of ∼64-75%, as revealed by scanning electron microscopy and micro-CT analyses, respectively. Furthermore, thermogravimetric analysis revealed that the CS-BHA scaffold lost 70% of its weight when heated up to 1000 °C, which is characteristic of CS phase decomposition in the biocomposite. In vitro studies demonstrated that the CS-BHA scaffolds were biocompatible toward Saos-2 osteoblast-like cells, showing high cell viability and a significant increase in cell proliferation across the measured timepoints compared to the controls.
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Affiliation(s)
- Jeffrey Huang
- Department
of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin 9016, New Zealand
| | - Jithendra Ratnayake
- Department
of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Niranjan Ramesh
- Department
of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin 9016, New Zealand
| | - George J. Dias
- Department
of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin 9016, New Zealand
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Lu EMC, Ratnayake J, Rich AM. Assessment of proliferating cell nuclear antigen (PCNA) expression at the invading front of oral squamous cell carcinoma. BMC Oral Health 2019; 19:233. [PMID: 31672124 PMCID: PMC6822390 DOI: 10.1186/s12903-019-0928-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 10/15/2019] [Indexed: 01/01/2023] Open
Abstract
Background Accurate prediction of the behaviour of oral squamous cell carcinoma (OSCC) is necessary to determine prognosis and provide appropriate treatment. Therefore, it is important to investigate potential prognostic markers to determine their predictive ability. Histological assessment of specific features at the invading front of oral squamous cell carcinomas has shown to provide accurate and reproducible prognostic information. Proliferating cell nuclear antigen (PCNA) is a nuclear marker known to reflect cell turnover and may be used as a marker for tumour aggressiveness. Methods Twenty cases of OSCC were histologically assessed to evaluate the correlation between proliferating cell nuclear antigen expression and invasive front grading. Each case was first assessed on a haematoxylin and eosin stained slide and an invading front grading (IFG) score was determined. In order to obtain a PCNA score, immunohistological staining was carried out using the peroxidase-labelled streptavidin-biotin technique with the monoclonal antibody PC10. Results In all cases, tumour islands had a periphery of intensely stained proliferating cell nuclear antigen-positive epithelial cells. The average IFG score was 8 ± 1.8, and the average PCNA score was 75% ± 11.2. Regression analysis was done using data from the IFG score and PCNA score and taking the latter as the predictor variable. The Pearson correlation coefficient was 0.134, with a p-value of 0.572. Conclusion Since the correlation between PCNA score and IFG score was not significant (p > 0.05), we conclude that there is no association between cell proliferation at the invading tumour front and the histological grading of OSCC.
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Affiliation(s)
- Emily Ming-Chieh Lu
- Faculty of Dentistry, The University of Otago, PO Box 647, 310 Great King Street, Dunedin, 9016, New Zealand
| | - Jithendra Ratnayake
- Faculty of Dentistry, The University of Otago, PO Box 647, 310 Great King Street, Dunedin, 9016, New Zealand.
| | - Alison Mary Rich
- Faculty of Dentistry, The University of Otago, PO Box 647, 310 Great King Street, Dunedin, 9016, New Zealand
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Hrebien S, Citi V, Garcia-Murillas I, Cutts R, Kozarewa I, Ratnayake J, de Bruin E, Schiavon G, Antunes De Melo e Oliveira A, Turner N. Utility of early circulating tumour DNA dynamics as a surrogate for progression free survival in the BEECH phase I/II trial in metastatic breast cancer. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz095.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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31
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Race J, Zilm P, Ratnayake J, Fitzsimmons T, Marchant C, Cathro P. Efficacy of laser and ultrasonic-activated irrigation on eradicating a mixed-species biofilm in human mesial roots. AUST ENDOD J 2019; 45:317-324. [PMID: 30623530 DOI: 10.1111/aej.12334] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2018] [Indexed: 12/16/2022]
Abstract
This study investigated the efficacy of Er,Cr:YSGG laser and ultrasonic activated irrigation on eradicating a mixed-species biofilm grown in root canals with complex anatomy. The biofilm was grown over 4-weeks in the root canals of decoronated human mandibular molar teeth. Control roots received no further treatment. The remaining roots were chemomechanically prepared using different irrigating protocols: 4% NaOCl and 15% EDTAC with ultrasonic activated irrigation and laser activated irrigation using power settings of 0.5 W and 0.75 W. Cellular viability was determined using serial plating. One tooth from each group was subjected to qualitative SEM analysis. Quantification by culturing revealed significant differences between control group and all other treatment groups. This study demonstrated that chemomechanical irrigation with laser and ultrasonic activated irrigation significantly reduced the bacterial load from complex root canal systems; however, there were no significant differences found between the experimental groups.
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Affiliation(s)
- Jonathan Race
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - Peter Zilm
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
| | | | - Tracy Fitzsimmons
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - Ceilidh Marchant
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - Peter Cathro
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia.,Faculty of dentistry, The University of Otago, Dunedin, New Zealand
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Lee RJ, Ratnayake J, Veerasamy A, Loch C, Cathro P, Brunton PA. Demographics, Practising Arrangements, and Standards: Survey among New Zealand Dentists. Int J Dent 2018; 2018:7675917. [PMID: 30581468 PMCID: PMC6276479 DOI: 10.1155/2018/7675917] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/14/2018] [Accepted: 10/29/2018] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND To determine the demographic profile and practising arrangements of general dentists in New Zealand. METHODS A questionnaire comprising 19 sections with 125 questions was distributed via mail to 351 general dentists in New Zealand who were selected, at random, from the Dental Council of New Zealand's 2016 register. RESULTS Two hundred and four questionnaires were returned, of which 188 were usable giving a response rate of 53.5%. The majority of the respondents (63.5%) were male and practice principals (56.8%). Fifty-nine percent of the practices were located in city or town centres with a wide geographic distribution. Sole practitioners accounted for 24.1% of respondents, with the mean number of dentists per practice being 3.2. The majority of respondents (71.6%) attended five or more continuing professional development courses in the past year. Ninety-one percent of respondents used a computerized management system, and 95.3% used the Internet. The use of nickel-titanium endodontic files (83.9%) and digital imaging (82.2%) was the most frequently cited clinical innovations. Articaine was the most popular local anaesthetic of choice. CONCLUSIONS Dentistry is an ever-changing profession, with evidence that NZ dentists continue to develop, learn, and embrace advancements in technologies to supply high-quality evidence-based treatment.
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Affiliation(s)
- Robert James Lee
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Jithendra Ratnayake
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Arthi Veerasamy
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Carolina Loch
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Peter Cathro
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
| | - Paul A. Brunton
- University of Otago, Faculty of Dentistry, 310 Great King Street, Dunedin 9016, New Zealand
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Van Cutsem E, Bang YJ, Mansoor W, Petty RD, Chao Y, Cunningham D, Ferry DR, Smith NR, Frewer P, Ratnayake J, Stockman PK, Kilgour E, Landers D. A randomized, open-label study of the efficacy and safety of AZD4547 monotherapy versus paclitaxel for the treatment of advanced gastric adenocarcinoma with FGFR2 polysomy or gene amplification. Ann Oncol 2018; 28:1316-1324. [PMID: 29177434 DOI: 10.1093/annonc/mdx107] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Background Approximately 5%-10% of gastric cancers have a fibroblast growth factor receptor-2 (FGFR2) gene amplification. AZD4547 is a selective FGFR-1, 2, 3 tyrosine kinase inhibitor with potent preclinical activity in FGFR2 amplified gastric adenocarcinoma SNU16 and SGC083 xenograft models. The randomized phase II SHINE study (NCT01457846) investigated whether AZD4547 improves clinical outcome versus paclitaxel as second-line treatment in patients with advanced gastric adenocarcinoma displaying FGFR2 polysomy or gene amplification detected by fluorescence in situ hybridization. Patients and methods Patients were randomized 3:2 (FGFR2 gene amplification) or 1:1 (FGFR2 polysomy) to AZD4547 or paclitaxel. Patients received AZD4547 80 mg twice daily, orally, on a 2 weeks on/1 week off schedule of a 21-day cycle or intravenous paclitaxel 80 mg/m2 administered weekly on days 1, 8, and 15 of a 28-day cycle. The primary end point was progression-free survival (PFS). Safety outcomes were assessed and an exploratory biomarker analysis was undertaken. Results Of 71 patients randomized (AZD4547 n = 41, paclitaxel n = 30), 67 received study treatment (AZD4547 n = 40, paclitaxel n = 27). Among all randomized patients, median PFS was 1.8 months with AZD4547 and 3.5 months with paclitaxel (one-sided P = 0.9581); median follow-up duration for PFS was 1.77 and 2.12 months, respectively. The incidence of adverse events was similar in both treatment arms. Exploratory biomarker analyses revealed marked intratumor heterogeneity of FGFR2 amplification and poor concordance between amplification/polysomy and FGFR2 mRNA expression. Conclusions AZD4547 did not significantly improve PFS versus paclitaxel in gastric cancer FGFR2 amplification/polysomy patients. Considerable intratumor heterogeneity for FGFR2 gene amplification and poor concordance between FGFR2 amplification/polysomy and FGFR2 expression indicates the need for alternative predictive biomarker testing. AZD4547 was generally well tolerated.
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Affiliation(s)
- E Van Cutsem
- Unit of Digestive Oncology, University Hospitals Leuven and KU Leuven, Leuven, Belgium
| | - Y-J Bang
- Biomedical Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - W Mansoor
- The Christie NHS Foundation Trust, Manchester
| | - R D Petty
- Medical Research Institute, University of Dundee, Dundee
| | - Y Chao
- Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - D Cunningham
- Gastrointestinal and Lymphoma Unit, Royal Marsden Hospital NHS Foundation Trust, Surrey
| | - D R Ferry
- Clinical Oncology, New Cross Hospital, Wolverhampton
| | - N R Smith
- Oncology Innovative Medicines and Early Development, AstraZeneca, Macclesfield
| | - P Frewer
- Oncology Innovative Medicines and Early Development, AstraZeneca, Cambridge, UK
| | - J Ratnayake
- Oncology Innovative Medicines and Early Development, AstraZeneca, Macclesfield
| | - P K Stockman
- Oncology Innovative Medicines and Early Development, AstraZeneca, Macclesfield
| | - E Kilgour
- Oncology Innovative Medicines and Early Development, AstraZeneca, Macclesfield
| | - D Landers
- Oncology Innovative Medicines and Early Development, AstraZeneca, Macclesfield
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Plutzer B, Zilm P, Ratnayake J, Cathro P. Comparative efficacy of endodontic medicaments and sodium hypochlorite againstEnterococcus faecalisbiofilms. Aust Dent J 2018; 63:208-216. [DOI: 10.1111/adj.12580] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2017] [Indexed: 11/28/2022]
Affiliation(s)
- B Plutzer
- School of Dentistry; Faculty of Health Science; The University of Adelaide; Adelaide South Australia Australia
| | - P Zilm
- School of Dentistry; Faculty of Health Science; The University of Adelaide; Adelaide South Australia Australia
| | - J Ratnayake
- University of Otago; Faculty of Dentistry; Dunedin Otago New Zealand
| | - P Cathro
- School of Dentistry; Faculty of Health Science; The University of Adelaide; Adelaide South Australia Australia
- University of Otago; Faculty of Dentistry; Dunedin Otago New Zealand
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Wang S, Cathro P, Heithersay G, Briggs N, Ratnayake J, Zilm P. A colourimetric evaluation of the effect of bacterial contamination on teeth stained with blood in vitro: Evaluation of the efficacy of two different bleaching regimes. Aust Dent J 2018; 63:253-260. [PMID: 29485695 DOI: 10.1111/adj.12604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2018] [Indexed: 12/01/2022]
Abstract
BACKGROUND Tooth discolouration could occur due to bacterial contamination in traumatized teeth. Hydrogen peroxide is the commonly used bleaching agent. However, due to concerns over safety, alternative bleaching regimes such as sodium perborate (S) and thiourea-hydrogen peroxide (T) have been investigated. METHODS Apices resected and pulp extirpated 99 premolars were divided into two groups. Group 1 and 2 was injected with blood and blood/bacteria, stored anaerobically for 35 days. The two groups were treated by bleaching with water, S or T. Teeth were rebleached after 7 days. Colourimetric evaluation was assessed using digital imaging, CasMatch standardization and CIE L*a*b colour system preoperatively, 35 days of staining and 7 and 14 of bleaching. A linear mixed model with fixed effects of time, group and bleach was used to examine colour difference. RESULTS Blood-stained teeth were significantly redder and darker on day 35 compared with blood/bacteria-stained teeth. After bleaching, blood-stained teeth retained significant redness compared with blood/bacteria-stained teeth using either S or T. T produced a significantly whiter shade in both the groups after 14 days. CONCLUSIONS Blood-stained teeth were significantly darker and red compared with blood/bacteria-stained teeth. T bleaching regime was more effective than S.
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Affiliation(s)
- S Wang
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - P Cathro
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia.,Faculty of Dentistry, University of Otago, Dunedin, Otago, New Zealand
| | - G Heithersay
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - N Briggs
- Data Management and Analysis Centre, University of Adelaide, Adelaide, South Australia, Australia
| | - J Ratnayake
- Faculty of Dentistry, University of Otago, Dunedin, Otago, New Zealand
| | - P Zilm
- School of Dentistry, Faculty of Health Science, The University of Adelaide, Adelaide, South Australia, Australia
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Stenhouse M, Zilm P, Ratnayake J, Cathro P. Investigation of the effect of rapid and slow external pH increases on Enterococcus faecalis biofilm grown on dentine. Aust Dent J 2018; 63:224-230. [PMID: 29327470 DOI: 10.1111/adj.12582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND Calcium hydroxide is a common endodontic medicament and has an antimicrobial effect by increasing the localized pH within the root canal. However, Enterococcus faecalis has shown some resistance to calcium hydroxide. METHODS A flow cell apparatus was used to grow an E. faecalis biofilm on dentine discs. Following 4 weeks growth in Todd Hewitt Broth, flow cells were exposed to either a rapid or slow increase to pH 11.5 or 12.5. Cellular viability was determined using serial plating and the number of colony-forming units was normalized against the cellular protein content. Scanning electron microscopy was carried out to qualitatively observe the effects of the different rates of pH increase. RESULTS A significant difference in viability between the pH rapid and slow groups was not shown in this study. Compared with pH 11.5 solutions, pH 12.5 solutions were more effective at killing bacteria although some E. faecalis still survived. CONCLUSIONS Enterococcus faecalis did not adapt and develop a greater resistance to high pH following a slow rise in pH compared with a rapid rise in pH. As expected, pH 12.5 was more effective in reducing bacterial numbers compared with pH 11.5 although E. faecalis was not completely eliminated.
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Affiliation(s)
- M Stenhouse
- Adelaide Dental School, Faculty of Health and Medical Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - P Zilm
- Adelaide Dental School, Faculty of Health and Medical Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - J Ratnayake
- Faculty of Dentistry, Dunedin, Otago, Australia
| | - P Cathro
- Adelaide Dental School, Faculty of Health and Medical Science, The University of Adelaide, Adelaide, South Australia, Australia.,Faculty of Dentistry, Dunedin, Otago, Australia
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Schneeweiss A, Chia S, Hickish T, Harvey V, Eniu A, Hegg R, Tausch C, Seo J, Tsai YF, Ratnayake J, McNally V, Ross G, Cortés J. Pertuzumab plus trastuzumab in combination with standard neoadjuvant anthracycline-containing and anthracycline-free chemotherapy regimens in patients with HER2-positive early breast cancer: a randomized phase II cardiac safety study (TRYPHAENA). Ann Oncol 2013; 24:2278-84. [DOI: 10.1093/annonc/mdt182] [Citation(s) in RCA: 703] [Impact Index Per Article: 63.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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Schneeweiss A, Chia S, Hegg R, Tausch C, Deb R, Ratnayake J, Kiermaier A, McNally V, Ross G, Cortes J. Biomarker (BM) Analyses of a Phase II Study of Neoadjuvant Pertuzumab and Trastuzumab With and Without Anthracycline (ATC)-Containing Chemotherapy for Treatment of HER2-Positive Early Breast Cancer (BC) (Tryphaena). Ann Oncol 2012. [DOI: 10.1016/s0923-7534(20)32767-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Munoz-Mateu M, Urruticoechea A, Separovic R, Erfán J, Bachelot TD, Canon J, Kovalenko N, Staroslawska E, Pikó B, Veyret C, Pribylova O, Ciule DL, Ratnayake J, Das S, Mayne K, Ross G. Trastuzumab plus capecitabine with or without pertuzumab in patients with HER2-positive MBC whose disease has progressed during or following trastuzumab-based therapy for first-line metastatic disease: A multicenter, randomized, two-arm, phase II study (PHEREXA). J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.tps118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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