Papers by Universiti Kebangsaan Malaysia Dental Science Research
Evidence-Based Complementary and Alternative Medicine, 2012
Myristica fragrans Houtt is mostly cultivated for spices in Penang Island, Malaysia. The ethyl ac... more Myristica fragrans Houtt is mostly cultivated for spices in Penang Island, Malaysia. The ethyl acetate and ethanol extracts of flesh, mace and seed of Myristica fragrans was evaluated the bactericidal potential against three Gram-positive cariogenic bacteria (Streptococcus mutans ATCC 25175, Streptococcus mitis ATCC 6249, and Streptococcus salivarius ATCC 13419) and three Gram-negative periodontopathic bacteria (Aggregatibacter actinomycetemcomitans ATCC 29522, Porphyromonas gingivalis ATCC 33277, and Fusobacterium nucleatum ATCC 25586). Antibacterial activities of the extracts was determined by twofold serial microdilution, with minimum inhibitory concentrations (MIC) ranging from 1.25 to 640 mg/mL and 0.075 to 40 mg/mL. The minimum bactericidal concentration (MBC) was obtained by subculturing method. Among all extracts tested, ethyl acetate extract of flesh has the highest significant inhibitory effects against Gram-positive and Gram-negative bacteria with mean MIC value ranging from 0.625 to 1.25 +/- 0.00 (SD) mg/mL; P = 0.017) and highest bactericidal effects at mean MBC value ranging from 0.625 mg/mL to 20 +/- 0.00 (SD) mg/mL. While for seed and mace of Myristica fragrans, their ethanol extracts exhibited good antibacterial activity against both groups of test pathogens compared to its ethyl acetate extracts. All of the extracts of Myristica fragrans did not show any antibacterial activities against Fusobacterium nucleatum ATCC 25586. Thus, our study showed the potential effect of ethyl acetate and ethanol extracts from flesh, seed and mace of Myristica fragrans to be new natural agent that can be incorporated in oral care products.
JOURNAL OF ORAL BIOSCIENCES, 2021
Background: Periodontitis is a noncommunicable inflammatory disease of the soft tissue and bone s... more Background: Periodontitis is a noncommunicable inflammatory disease of the soft tissue and bone surrounding the teeth in the jaw, which affects susceptible individuals with poor oral hygiene. A growing interest has been seen in the use of dietary supplements and natural products for the treatment and prevention of periodontitis. Vitamin E consists of two major groups, namely tocopherols and tocotrienols, which are botanical lipophilic compounds with excellent anti-inflammatory and antioxidant properties.
Highlight: This review aimed to summarize the preclinical and clinical findings on the effects of vitamin E on periodontitis. The current literature suggests that vitamin E could improve the periodontal status by correcting redox status imbalance, reducing inflammatory responses, and promoting wound healing, thus highlighting the potential of vitamin E in the management of periodontitis.
Conclusion: Direct evidence for the use of vitamin E supplementation or treatment of periodontitis in humans is still limited. More well-designed and controlled studies are required to ascertain its effectiveness. (C) 2021 Japanese Association for Oral Biology.
UNDERSEA AND HYPERBARIC MEDICINE, 2021
Background: Changes in barometric pressure conditions that occur during flying and diving under h... more Background: Changes in barometric pressure conditions that occur during flying and diving under hyperbaric oxygen conditions were found to influence the retention of dental restorations.
Aim: This experimental laboratory study aimed to evaluate the bond strength of glass fiber posts after being cemented with self-adhesive resin cement (RelyXT Unicem, 3M ESPE) and self-etch adhesive resin cement (RelyXT Ultimate, 3M ESPE) under normal atmospheric pressure and hyperbaric pressure cycles that simulate diving conditions.
Methods: A total of 40 extracted, single-rooted mandibular premolars were treated endodontically and randomly divided into two groups according to the cements used for fiber post cementation. Each group was further randomly divided into two equal subgroups that were subjected to normal atmospheric pressure conditions and a simulated hyperbaric condition in a hyperbaric chamber. The pull-out bond strength of fiber posts was tested using a universal testing machine. Data were analyzed using one-way analysis of variance with Tukey post-hoc test (p< 0.05).
Results: At normal atmospheric pressure the mean value of the pull- out bond strength of RelyX Ultimate cement was significantly higher than that of RelyX Unicem cement. At hyperbaric pressure condition no significant difference was found between the mean values of the pull-out bond strength of RelyX Ultimate and RelyX Unicem cement.
Conclusion: Hyperbaric pressure cycles demonstrated improved pull-out bond strength of glass fiber posts in RelyX Unicem cement but did not have significant effect on pull-out bond strength in RelyX Ultimate cement. Both resin cements have similar pull-out bond strength of glass fibers post after simulated dives.
ANTIBIOTICS-BASEL, 2021
The aim of this systematic review is to compare the clinical efficacy of repeated applications of... more The aim of this systematic review is to compare the clinical efficacy of repeated applications of local drug delivery and adjunctive agents (LDAs) in nonsurgical periodontal therapy (NSPT) compared to subgingival mechanical debridement (SMD) alone. The Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, EMBASE, Web of Science, hand-searched literature and grey literature databases were searched for randomized controlled clinical trials (RCTs) with a minimum of 6-month follow-up. The outcomes of interest were changes in probing pocket depth and clinical attachment level as well as patient-centred outcomes. Of 1094 studies identified, 16 RCTs were included in the qualitative analysis. Across 11 different adjuncts analysed, only two studies utilizing minocycline gel/ointment and antimicrobial photodynamic therapy (aPDT) with indocyanine green photosensitizer had statistically significant differences in primary outcomes when compared to their control groups. Only one study on aPDT methylene blue 0.005% had compared single versus multiple applications against its control group. A mean range of 0.27-3.82 mm PD reduction and -0.09-2.82 mm CAL gain were observed with repeated LDA application. Considerable clinical heterogeneity and methodological flaws in the included studies preclude any definitive conclusions regarding the clinical efficacy of repeated LDA applications. Future RCTs with a direct comparison between single and repeated applications should be conducted to confirm or refute the clinical advantages of repeated LDA application in the nonsurgical management of periodontitis.
BMC ORAL HEALTH, 2021
Background Siwak is a chewing stick used as an oral hygiene aid associated with Muslim communitie... more Background Siwak is a chewing stick used as an oral hygiene aid associated with Muslim communities across the globe since more than 1500 years ago. Used either exclusively or in conjunction with a regular toothbrush, there is evidence supporting its clinical effectiveness in plaque control, but adverse effects on periodontal health remains inconclusive. Objective This study aims to systematically review the wide range of data and literatures related to siwak practice and its effect on periodontal health. Method The review was conducted based on scoping review techniques, searching literature in EBSCOHOST, PubMed, SCOPUS and Google scholar databases using the following search terms: "siwak' or 'miswak' or 'chewing stick" for intervention, and "periodontium or 'periodontal' or 'periodontal health' or 'periodontal disease" for outcome. Articles published between January 1990 to March 2021 and written in English language were included. Results A total of 721 articles collected from the search and 21 of them were eligible for the final analysis. Results of this study was described based on clinical and antibacterial reporting of siwak, method of siwak practice and its adverse effect on oral health. Siwak was found effective at removing dental plaque and improving periodontal health over time although its effect on subgingival microbiota was inconclusive. Presence of gingival recession and clinical attachment loss were much more commonly reported in siwak users, attributable to variations in the methods employed for tooth cleaning using the siwak. Conclusion There is substantial evidence that the lack of standardised reporting for effective siwak use may have resulted in contradictory findings about its oral hygiene benefits and adverse effects. As such, future work on safe and effective siwak practice is to be advocated among its users.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2021
Caries is one of the non-communicable diseases that has a high prevalence trend. The current meth... more Caries is one of the non-communicable diseases that has a high prevalence trend. The current methods used to detect caries require sophisticated laboratory equipment, professional inspection, and expensive equipment such as X-ray imaging device. A non-invasive and economical method is required to substitute the conventional methods for the detection of caries. UV absorption spectroscopy coupled with chemometrics analysis has emerged as a good potential candidate for such an application. Data preprocessing methods such as mean centre, autoscale and Savitzky-Golay smoothing were implemented to enhance the signal-to-noise ratio of spectra data. Various classification algorithms namely K-nearest neighbours (KNN), logistic regression (LR) and linear discriminant analysis (LDA) were implemented to classify the severity of dental caries into International Caries Detection and Assessment System (ICDAS) scores. The performance of the prediction model was measured and comparatively analysed based on the accuracy, precision, sensitivity, and specificity. The LDA algorithm combined with the Savitzky-Golay preprocessing method had shown the best result with respect to the validation data accuracy, precision, sensitivity and specificity, where each had values of 0.90, 1.00, 0.86 and 1.00 respectively. The area under the curve of the ROC plot computed for the LDA algorithm was 0.95, which indicated that the prediction algorithm was capable of differentiating normal and caries teeth excellently.
Transboundary and Emerging Diseases, 2021
This study describes the pathological changes, antibody response, isolation and distribution patt... more This study describes the pathological changes, antibody response, isolation and distribution patterns following exposure of non-pregnant goats to live Brucella melitensis. Eighteen healthy adult female goats were divided into two equal groups. Group 1 was infected via conjunctival sac with 109 cfu/ml of B. melitensis, while Group 2 was similarly exposed to sterile PBS. Serum and swabs from the eyes and vagina were collected at 5-day intervals. On days 15, 30 and 75 post-infection, 3 goats from each group were killed before the conjunctiva, ovary, oviduct, uterine horn, uterine body and vagina, the submandibular, prescapular and supramammary lymph nodes, the mammary gland, liver, spleen, urinary bladder and synovial membranes were collected for bacterial isolation and pathological study. Exposure of non-pregnant goats to B. melitensis did not produce clinical signs and gross lesions but produced mild necrosis and inflammation in the lymph nodes, the organs of reproductive tract, the mammary gland and urinary bladder. In general, microscopic lesions were most severe in the D75 goats, followed by D30 and D15 goats. Brucella melitensis was most frequent and significantly (p < .05) isolated from the D30 (64.4 ± 25.2%) and least from D15 goats (39.3 ± 26.0%) goats. The organs that were most frequently isolated were the uterus, followed by the mammary gland, supramammary lymph node and urinary bladder. Earliest isolation from the ocular swabs was on day 5, while the vaginal swabs were on day 20 post-infection. The antibody response showed first significant (p < .05) increase on day 15 and reached peak on day 45 post-infection, corresponding with the first detection of sero-converter goats by the RBPT at 15 days and by the CFT at 40 days post-infection. In conclusion, infected non-pregnant goats shed B. melitensis through the vagina by day 20. The sero-positive goats were detectable by RBPT after 15 days but by CFT after 40 days. Since both serological tests detected positive goats at different time period of infection, paired-serum samplings might reduce this discrepancy.
Case Reports in Dentistry, 2021
Subcutaneous emphysema (SE) is a swelling which develops due to air entrapped underneath the subc... more Subcutaneous emphysema (SE) is a swelling which develops due to air entrapped underneath the subcutaneous tissue and facial planes causing distention of the overlying skin. SE can develop due to trauma, surgery, or infection. The diagnosis of SE is mostly based on clinical findings of crepitation upon palpation of the swelling. Once diagnosed, SE is usually managed by close observation and in some cases may require surgical decompression and antibiotic prophylaxis. We report a rare case of SE of the left malar which developed following closure of oroantral communication using the buccal fat pad.
Frontiers in Medicine, 2021
Background: Aerosol-producing dental procedures are of concern in the spread of infections, espec... more Background: Aerosol-producing dental procedures are of concern in the spread of infections, especially during the COVID-19 pandemic. Periodontal prophylaxis is the most common aerosol-producing procedure conducted in dental practice globally. During COVID-19, many national and international organizations advocated the use of pre-procedural mouth rinsing to prevent the spread of infections from aerosol-generating procedures in the dental setting; however, many questioned the scientific basis for such recommendations. Objective: This systematic review aimed to evaluate the effectiveness of pre-procedural rinsing when preforming periodontal prophylaxis in reducing aerosol contamination in the dental setting. Methods: A comprehensive standardized search strategy was employed, informed by a defined PICO question across four electronic databases. The review of the literature was conducted using the PRISMA framework. Agreement between assessors was determined throughout. Synthesis of study characteristics and key outcomes were conducted. Cochrane's risk-of-bias tool for randomized trials (RoB 2) was employed to assess the quality/bias among studies. Results: The initial search yielded 731 citations across the four databases; 95 potentially effective studies were identified, with 56 effective studies found. Thirty randomized control trial studies were identified, 21 with a focus on effectiveness of pre-procedural mouth rinsing, involving 984 participants (aged 18–70). Agreement between assessors was high (Kappa >0.80). Various pre-procedural mouth rinses were tested, most frequently chlorhexidine (CHX) in 18 studies. The concentrations, volume, and prescribed duration of rinsing varied among studies, hampering meta-analyses. Nonetheless, all studies identified significant reductions in bacterial contamination, as measured by colony forming units (cfu). The effectiveness of CHX over other agents was evident with more than half of the studies (7/15) reporting over a 70% reduction in bacterial contamination (cfu). There were concerns over the risk of bias in most studies (76.2%); 19.0% had a high risk of bias and 4.8% were of low risk of bias. Conclusion: There is substantial evidence to support pre-procedural mouth rinsing, such as with chlorohexidine, to effectively reduce aerosol contamination when performing periodontal prophylaxis compared to mouth rinsing with water or not rinsing. © Copyright © 2021 Mohd-Said, Mohd-Dom, Suhaimi, Rani and McGrath.
European Journal of Dental Education, 2021
Introduction The computer-aided design/computer-aided manufacturing (CAD/CAM) technology has revo... more Introduction The computer-aided design/computer-aided manufacturing (CAD/CAM) technology has revolutionised dentistry at present. An operator's skills can affect the overall clinical duration and marginal accuracy of the prosthesis fabricated through this workflow. The aim of this study was to assess the effect of CAD/CAM hands-on training compared with that of a self-instructional video on the performance of dental students in digital impression and fabrication of a CAD/CAM crown. Methods In this cross-sectional study, 30 undergraduate dental students were shown a CEREC demonstration video. Each operator then captured a digital impression using the intra-oral scanner, and a crown was subsequently milled. All participants underwent a training course before repeating the process. Marginal discrepancy for each crown on its abutment tooth was measured before and after training using a stereomicroscope and was evaluated using Wilcoxon signed rank test. The duration taken for the process was recorded before and after training and evaluated using paired t-test. Results The overall mean +/- standard deviation marginal adaptation for the CEREC crowns was 78.15 +/- 42.83 mu m before training and 52.41 +/- 17.12 mu m after training. The Wilcoxon signed rank test found significant difference (p < .05) in terms of marginal adaptation of crowns fabricated before and after training. Paired t-tests showed that the time efficiency after training significantly improved compared with that before training. Conclusions Training with guided feedback is crucial to improve the time efficiency of making a digital impression and marginal adaptation of fixed prosthesis using the CAD/CAM technology.
Health Informatics Journal, 2021
This study aimed to evaluate the effect of a novel progressive web application (PWA) on the patie... more This study aimed to evaluate the effect of a novel progressive web application (PWA) on the patient's oral and denture knowledge and hygiene. Fifty-two removable partial denture wearers were randomised to receive education using the PWA, or verbal instructions accompanied by demonstration of hygienic procedures. Changes in the participants' knowledge score, plaque index, gingival index and denture plaque was evaluated during a follow-up period of 3 months. The participants' acceptance of PWA was explored through usage logs and a feedback form. Both groups showed significant improvement in knowledge scores, oral and denture hygiene indices (p < 0.001) after education. The PWA group demonstrated significantly lower gingival index score than control (p = 0.008) at the third month review. In conclusion, there is potential of using mobile application in educating elderly patients and the PWA is a viable option for providing postdenture delivery instructions.
Sains Malaysiana, 2021
Titanium-hydroxyapatite (Ti-HA) based composites have been widely investigated as viable material... more Titanium-hydroxyapatite (Ti-HA) based composites have been widely investigated as viable materials to be used in dentistry. However, sintering of these composites is very challenging due to decomposition of HA and oxidation of Ti. The objective of this study was to investigate the effect of incorporating a bioactive glass in Ti-HA composites sintered in different atmospheric conditions. The bioactive glass was prepared and added to different percentages of Ti-HA mixtures and divided into two groups. Samples in Group 1 were sintered with air atmosphere, while samples in Group 2 were sintered with vacuum furnace. All samples were later subjected to XRD, SEM, density, micro-hardness, and compression strength tests. XRD results showed that in Group 1, the major phases were assigned to Ti and HA while the minor phases were assigned to oxidised Ti. Whereas, Group 2 showed that the major phases were assigned to HA and the minor phases showed decomposition of HA to Ca-3(PO4)(2) (TCP) and Ca-4(PO4)(2)O (TTCP). Oxidized Ti was also present in this group. In terms of density, micro-hardness and compression strength, statistical analyses showed that samples in Group 1 have a significant difference (p = 0.000) as compared to those in Group 2. Sintering Ti-HA composites incorporated with BG by using air atmosphere furnace could reduce the decomposition of HA and oxidation of Ti, thus improve the density, micro-hardness and compression strength of the composites.
PLoS One, 2021
Melicope glabra (Blume) T. G. Hartley from the Rutaceae family is one of the richest sources of p... more Melicope glabra (Blume) T. G. Hartley from the Rutaceae family is one of the richest sources of plant secondary metabolites, including coumarins and flavanoids. This study investigates the free radical scavenging and antibacterial activities of M. glabra and its isolated compounds. M. glabra ethyl acetate and methanol extracts were prepared using the cold maceration technique. The isolation of compounds was performed with column chromatography. The free radical scavenging activity of the extracts and isolated compounds were evaluated based on their oxygen radical absorbance capacity (ORAC) activities. The extracts and compounds were also subjected to antibacterial evaluation using bio-autographic and minimal inhibitory concentration (MIC) techniques against two oral pathogens, Enterococcus faecalis and Streptococcus mutans. Isolation of phytoconstituents from ethyl acetate extract successfully yielded quercetin 3, 5, 3'-trimethyl ether (1) and kumatakenin (2), while the isolation of the methanol extract resulted in scoparone (3), 6, 7, 8-trimethoxycoumarin (4), marmesin (5), glabranin (6), umbelliferone (7), scopoletin (8), and sesamin (9). The study is the first to isolate compound (1) from Rutaceae plants, and also the first to report the isolation of compounds (2-5) from M. glabra. The ORAC evaluation showed that the methanol extract is stronger than the ethyl acetate extract, while umbelliferone (7) exhibited the highest ORAC value of 24 965 μmolTE/g followed by glabranin (6), sesamin (9) and scopoletin (8). Ethyl acetate extract showed stronger antibacterial activity towards E. faecalis and S. mutans than the methanol extract with MIC values of 4166.7 ± 1443.4 μg/ml and 8303.3 ± 360.8 μg/ml respectively. Ethyl acetate extract inhibited E. faecalis growth, as shown by the lowest optical density value of 0.046 at a concentration of 5.0 mg/mL with a percentage inhibition of 95%. Among the isolated compounds tested, umbelliferone (7) and sesamin (9) exhibited promising antibacterial activity against S. mutans with both exhibiting MIC values of 208.3 ± 90.6 μg/ml. Findings from this study suggests M. glabra as a natural source of potent antioxidant and antibacterial agents.
Journal of Oral Biosciences, 2021
Background: Periodontitis is a noncommunicable inflammatory disease of the soft tissue and bone s... more Background: Periodontitis is a noncommunicable inflammatory disease of the soft tissue and bone surrounding the teeth in the jaw, which affects susceptible individuals with poor oral hygiene. A growing interest has been seen in the use of dietary supplements and natural products for the treatment and prevention of periodontitis. Vitamin E consists of two major groups, namely tocopherols and tocotrienols, which are botanical lipophilic compounds with excellent anti-inflammatory and antioxidant properties. Highlight: This review aimed to summarize the preclinical and clinical findings on the effects of vitamin E on periodontitis. The current literature suggests that vitamin E could improve the periodontal status by correcting redox status imbalance, reducing inflammatory responses, and promoting wound healing, thus highlighting the potential of vitamin E in the management of periodontitis. Conclusion: Direct evidence for the use of vitamin E supplementation or treatment of periodontitis in humans is still limited. More well-designed and controlled studies are required to ascertain its effectiveness. © 2021 Japanese Association for Oral Biology
Cleft Palate-Craniofacial Journal, 2021
Objective: The virtual cone beam computed tomography–derived 3-dimensional model was compared wit... more Objective: The virtual cone beam computed tomography–derived 3-dimensional model was compared with the scanned conventional model used in the fabrication of a palatal obturator for a patient with a large palatal defect. Design: A digitally derived 3-dimensional maxillary model incorporating the palatal defect was generated from the patient’s existing cone beam computerized tomography data and compared with the scanned cast from the conventional impression for linear dimensions, area, and volume. The digitally derived cast was 3-dimensionally printed and the obturator fabricated using traditional techniques. Similarly, an obturator was fabricated from the conventional cast and the fit of both final obturator bulbs were compared in vivo. Results: The digitally derived model produced more accurate volumes and surface areas within the defect. The defect margins and peripheries were overestimated which was reflected clinically. Conclusion: The digitally derived model provided advantages in the fabrication of the palatal obturator; however, further clinical research is required to refine consistency. © American Cleft Palate-Craniofacial Association. All rights reserved 2020.
BMC Medical Education, 2021
Background: A good understanding of the bi-directional relationship between diabetes and periodon... more Background: A good understanding of the bi-directional relationship between diabetes and periodontitis is essential to ensure the successful management of both diseases. This study aimed to develop and evaluate an integrated diabetes-periodontitis nutrition and health education module. Methods: The module was developed as an iterative and review process by five experts in nutrition and dietetics, periodontics, and dental public health. It consisted of three phases: (i) needs assessment on module contents and characteristics, (ii) module development and (iii) module evaluation by experts. Twelve healthcare professionals aged between 30 and 53 years (average 13.5 years of working experience) validated the module contents and its comprehensibility using the Patient Education Materials Assessment Tool for printable materials (PEMAT-P) and audio-visual materials (PEMAT-A/V). Scores of 0 (disagree) or 1 (agree) were given for sets of understandability and actionability statements and presented as a total percentage. Results: Seventeen infographic-flip charts and 13 short-videos were developed in the Malay language and grouped into four topics: (i) Introduction to Diabetes and Periodontitis, (ii) Diabetes and Periodontitis Care, (iii) Lifestyle Modification, and (iv) Myths and Facts. Flip charts were rated between 76-100% for understandability and 80–100% for actionability, while videos rated between 90-100% for understandability and 100% for actionability, respectively. Conclusion: Overall, the newly developed module ranked high median scores for understandability and actionability. This finding reflects positive acceptance of the integrated module among the various healthcare professionals involved in managing patients with diabetes and periodontitis. © 2021, The Author(s).
BMC Oral Health, 2021
Background: Mesenchymal stem cells isolated from the dental pulp of primary and permanent teeth c... more Background: Mesenchymal stem cells isolated from the dental pulp of primary and permanent teeth can be differentiated into different cell types including osteoblasts. This study was conducted to compare the morphology and osteogenic potential of stem cells from exfoliated deciduous teeth (SHED) and dental pulp stem cells (DPSC) in granular hydroxyapatite scaffold (gHA). Preosteoblast cells (MC3T3-E1) were used as a control group. Methodology: The expression of stemness markers for DPSC and SHED was evaluated using reverse transcriptase-polymerase chain reaction (RT-PCR). Alkaline phosphatase assay was used to compare the osteoblastic differentiation of these cells (2D culture). Then, cells were seeded on the scaffold and incubated for 21 days. Morphology assessment using field emission scanning electron microscopy (FESEM) was done while osteogenic differentiation was detected using ALP assay (3D culture). Results: The morphology of cells was mononucleated, fibroblast-like shaped cells with extended cytoplasmic projection. In RT-PCR study, DPSC and SHED expressed GAPDH, CD73, CD105, and CD146 while negatively expressed CD11b, CD34 and CD45. FESEM results showed that by day 21, dental stem cells have a round like morphology which is the morphology of osteoblast as compared to day 7. The osteogenic potential using ALP assay was significantly increased (p < 0.01) in SHED as compared to DPSC and MC3T3-E1 in 2D and 3D cultures. Conclusion: gHA scaffold is an optimal scaffold as it induced osteogenesis in vitro. Besides, SHED had the highest osteogenic potential making them a preferred candidate for tissue engineering in comparison with DPSC. © 2021, The Author(s).
Applied Sciences (Switzerland), 2021
Osteoradionecrosis (ORN) of the jaws and medication-related osteonecrosis of the jaws (MRONJ) are... more Osteoradionecrosis (ORN) of the jaws and medication-related osteonecrosis of the jaws (MRONJ) are uncommon but serious diseases affecting the oral and maxillofacial region with clinically similar appearance but distinct pathophysiology. Management of ORN and MRONJ is inherently challenging and the treatment outcomes are unpredictable. The use of autologous platelet concentrates (APCs) to promote hard and soft tissue healing is well described in the literature, and the efficacy of leucocyte and platelet-rich fibrin (L-PRF) has been well documented in a number of clinical studies. The aim of this study was to present our treatment strategy and the outcomes of incorpo-rating L-PRF as a surgical adjunct in management of ORN and MRONJ in our centre. Methods: eight cases of ORN and MRONJ were treated with a combination of sequestrectomy and L-PRF as a surgical adjunct. Results: the overall success was 87.5%. Using L-PRF as an adjunct, we were able to predictably manage ORN and MRONJ without causing significant morbidity. Conclusion: our experience shows that L-PRF may be used as a valuable and cost-effective adjunct to surgical management of ORN and MRONJ. However, due to a limited number of patients, and a short period of review, the true effectiveness of the method is yet to be demonstrated in a longer follow-up study including a greater number of patients, besides the inclusion of a control group. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Australian Endodontic Journal, 2021
This study aimed to evaluate and compare the frequency of microcracks and its severity at differe... more This study aimed to evaluate and compare the frequency of microcracks and its severity at different root canal dentin locations, after preparation with thermomechanically heat-treated engine-driven nickel-titanium instruments. Forty mandibular premolars were assigned to four experimental groups (n = 10): ProTaper Next, ProTaper Gold, WaveOne Gold and Reciproc Blue. After pre-instrumentation micro-computed tomography scans, the root canals were prepared to size 25. Following post-instrumentation scans, pre- and post-instrumentation scanned images were analysed for the presence and extent of dentinal defects. A total of 56 500 cross-sectional images were obtained, showing that less than 2.3% with pre-existing dentinal microcracks. No new microcracks were identified during the post-instrumentation analyses. No significant association was found between the types of dentinal defects, file motions and sequences. Thermomechanically heat-treated rotary files did not induce the formation of new microcracks. There was also no association between the kinematic motions and sequences of the rotary instruments to the types of dentinal defects. © 2021 Australian Society of Endodontology Inc
Materials Letters, 2020
This study aimed to investigate the machinability of zirconia blocks pre-sintered at four differe... more This study aimed to investigate the machinability of zirconia blocks pre-sintered at four different temperatures (900 °C, 1000 °C, 1100 °C, and 1200 °C). Vickers hardness and fracture toughness were measured to obtain the brittleness index (BI) of the zirconia blocks. The shrinkage percentage of the blocks pre-sintered at different temperatures was also determined upon final sintering at 1500 °C. The blocks were then subjected to machining, and the machined surfaces were morphologically analyzed. Although the materials pre-sintered at 900 °C and 1000 °C could be machined, noticeable trace lines and grooves formed on the machined surface due to lack of strength prior to sintering. BI and surface morphology confirmed that the new zirconia block can be milled at a pre-sintering temperature of 1100 °C and can achieve an acceptable shrinkage value for machining upon final sintering. © 2019 Elsevier B.V.
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Papers by Universiti Kebangsaan Malaysia Dental Science Research
Highlight: This review aimed to summarize the preclinical and clinical findings on the effects of vitamin E on periodontitis. The current literature suggests that vitamin E could improve the periodontal status by correcting redox status imbalance, reducing inflammatory responses, and promoting wound healing, thus highlighting the potential of vitamin E in the management of periodontitis.
Conclusion: Direct evidence for the use of vitamin E supplementation or treatment of periodontitis in humans is still limited. More well-designed and controlled studies are required to ascertain its effectiveness. (C) 2021 Japanese Association for Oral Biology.
Aim: This experimental laboratory study aimed to evaluate the bond strength of glass fiber posts after being cemented with self-adhesive resin cement (RelyXT Unicem, 3M ESPE) and self-etch adhesive resin cement (RelyXT Ultimate, 3M ESPE) under normal atmospheric pressure and hyperbaric pressure cycles that simulate diving conditions.
Methods: A total of 40 extracted, single-rooted mandibular premolars were treated endodontically and randomly divided into two groups according to the cements used for fiber post cementation. Each group was further randomly divided into two equal subgroups that were subjected to normal atmospheric pressure conditions and a simulated hyperbaric condition in a hyperbaric chamber. The pull-out bond strength of fiber posts was tested using a universal testing machine. Data were analyzed using one-way analysis of variance with Tukey post-hoc test (p< 0.05).
Results: At normal atmospheric pressure the mean value of the pull- out bond strength of RelyX Ultimate cement was significantly higher than that of RelyX Unicem cement. At hyperbaric pressure condition no significant difference was found between the mean values of the pull-out bond strength of RelyX Ultimate and RelyX Unicem cement.
Conclusion: Hyperbaric pressure cycles demonstrated improved pull-out bond strength of glass fiber posts in RelyX Unicem cement but did not have significant effect on pull-out bond strength in RelyX Ultimate cement. Both resin cements have similar pull-out bond strength of glass fibers post after simulated dives.
Highlight: This review aimed to summarize the preclinical and clinical findings on the effects of vitamin E on periodontitis. The current literature suggests that vitamin E could improve the periodontal status by correcting redox status imbalance, reducing inflammatory responses, and promoting wound healing, thus highlighting the potential of vitamin E in the management of periodontitis.
Conclusion: Direct evidence for the use of vitamin E supplementation or treatment of periodontitis in humans is still limited. More well-designed and controlled studies are required to ascertain its effectiveness. (C) 2021 Japanese Association for Oral Biology.
Aim: This experimental laboratory study aimed to evaluate the bond strength of glass fiber posts after being cemented with self-adhesive resin cement (RelyXT Unicem, 3M ESPE) and self-etch adhesive resin cement (RelyXT Ultimate, 3M ESPE) under normal atmospheric pressure and hyperbaric pressure cycles that simulate diving conditions.
Methods: A total of 40 extracted, single-rooted mandibular premolars were treated endodontically and randomly divided into two groups according to the cements used for fiber post cementation. Each group was further randomly divided into two equal subgroups that were subjected to normal atmospheric pressure conditions and a simulated hyperbaric condition in a hyperbaric chamber. The pull-out bond strength of fiber posts was tested using a universal testing machine. Data were analyzed using one-way analysis of variance with Tukey post-hoc test (p< 0.05).
Results: At normal atmospheric pressure the mean value of the pull- out bond strength of RelyX Ultimate cement was significantly higher than that of RelyX Unicem cement. At hyperbaric pressure condition no significant difference was found between the mean values of the pull-out bond strength of RelyX Ultimate and RelyX Unicem cement.
Conclusion: Hyperbaric pressure cycles demonstrated improved pull-out bond strength of glass fiber posts in RelyX Unicem cement but did not have significant effect on pull-out bond strength in RelyX Ultimate cement. Both resin cements have similar pull-out bond strength of glass fibers post after simulated dives.