NOORHAYATI BINTI RAJA MOHD

@um.edu.my

Lecturer and Department of Restorative Dentistry / Faculty of Dentistry
University of Malaya

NOORHAYATI BINTI RAJA MOHD


         Download Compact PDF  
https://researchid.co/hayatiraja

RESEARCH INTERESTS

RESTORATIVE DENTISTRY
MAXILLOFACIAL PROSTHODONTICS
PROSTHETICS DENTISTRY
10

Scopus Publications

Scopus Publications

  • Color Stability of CAD-CAM Laminate Veneer after Aging and Exposure to Food Spices
    Sains Malaysiana, 2025
  • Artificial intelligence in dentistry: a review of ChatGPT’s role and potential
    Muaiyed Buzayan, I. Sivakumar, N. R. Mohd
    Quintessence International, 2023
  • KNOWLEDGE, ATTITUDE, AND PRACTICE TOWARDS COVID-19 PANDEMIC AMONGST UNDERGRADUATE DENTAL STUDENT: A CROSS-SECTIONAL STUDY
    Journal of Health and Translational Medicine, 2023
  • Antifungal effects of eugenol on Candida albicans adherence to denture polymers
    Zubaidah Zanul Abidin, Nosizana Mohd Salleh, Wan Harun Himratul-Aznita, Siti Fauzza Ahmad, Ghee Seong Lim, et al.
    Peerj, 2023
    Background The study’s objective is to assess the adherence of C. albicans in different types of denture polymers and the effectiveness of eugenol and commercialized denture cleansers in the removal of C. albicans. Three types of denture base polymers (Lucitone® 199 (High-Impact PMMA), Impact® (conventional PMMA) and Eclipse® (UDMA)) and two hard denture reline materials (Kooliner® and Tokuyama® Rebase II Fast) were used in this study. Methods Three hundred samples were prepared (6 × 2 mm disc shape) and divided into five groups of denture polymers (n = 60) and further subjected into five treatment groups (Polident®, Steradent, distilled water, eugenol 5-minutes, and eugenol 10-min). Three samples were extracted from each treatment group for baseline data (n = 12). Baseline data were used to calculate the initial number of C. albicans adherence. A 0.5 ml immersion solution from each specimen was cultured on YPD agar and incubated for 48 h at 37 °C. Visible colonies were counted using a colony counter machine (ROCKER Galaxy 230). Results The result showed that the denture base polymer significantly affected the initial adherence (p = 0.007). The removal of C. albicans was also considerably affected by the denture base polymers and denture cleansers (p < 0.05). Lucitone®, Tokuyama®, and Kooliner® denture base polymers immersed for 3 min in eugenol showed the best results of removal. Discussion This study’s overall results showed that all denture polymers used as denture bases had an effect on C. albicans initial adherence and removal from the denture base, and eugenol is comparable to commercialised denture cleansers in reducing the number of attached C. albicans on denture base polymers.
  • Undergraduate dental students’ perspective of online learning and their physical and mental health during COVID-19 pandemic
    Enas Abdalla Etajuri, Noorhayati Raja Mohd, Zahra Naimie, Norasmatul Akma Ahmad
    Plos One, 2022
    Background and objective COVID-19 pandemic continuously spread exacerbating global concerns. It had impacted all life aspects such as social, cultural, economic and education. This study assess the impact of COVID-19 pandemic on undergraduate dental students at Faculty of Dentistry, University of Malaya. The objective of this study is to evaluate the impact of the pandemic on physical and mental health of undergraduate dental students. Methods This is a cross-sectional study. An online questionnaire was administrated to 150 undergraduate dental students. The questionnaire included questions related to students’ demographic data, their concerns on academic achievement, their opinion on institution response, and the impact of the crisis on their mental and physical health. SPSS software v26.0 was used to analyse the collected data. Results A total of 147 respondents participated in the study. About 66% of the students felt comfortable in adapting to the new technology while 85.7% were concerned about the quality of online learning. Almost all students 98.6% expressed their doubts on the ability to pass the competency exams and to graduate on time, with only 49.7% agreed that clinical experience was effectively delivered through online classes. Most students were also concerned on the impact of the pandemic on their physical and emotional health 85.8% and 76.9% respectively. Conclusions The findings of our study highlight the positive adaptation of the students to online learning and using technology. On the other hand, the study indicates that the COVID-19 pandemic brings negative impacts on our students’ physical and mental health.
  • An alternative technique for fabrication of a tooth-supported removable partial overdenture: A case report
    Noorhayati Raja Mohd, S. Ahmad, E. Etajuri
    Journal of International Oral Health, 2021
    Overdenture is one of the recommended treatment methods for elderly patients with few remaining teeth and deeply resorbed ridges. Root retained under the denture base maintains more alveolar ridge resorption, which provides sensory feedback and improves the stability of the dentures. In addition, after endodontic therapy, the use of copings (short/long) and braces on the remaining teeth improves denture protection. This case report aimed to describe prosthodontic rehabilitation of a tooth-supported removable partial denture using a Locator attachment.A 48-year-old woman presented to the Faculty of Dentistry, University of Malaya, complaining looseness and repeated fracture of her denture, which led to difficulty in eating and chewing. She presented with Kennedy Classification II modification 1 on the maxilla with 23 and 24. The treatment plan was to provide her with maxillary cobalt–chromium overdenture using the Locator attachment system. The abutment teeth were designed, prefabricated using Locator, and were attached to the root of 23. Esthetics was achieved, and the patient reported satisfactory outcome.The present case report signifies that few remaining teeth are effectively preserved to support tooth-retained overdenture. This treatment approach was chosen considering the patient’s favorable inter ridge distance and economic status rather than full extractions accompanied by a complete denture or implant-supported overdenture. This technique using a Locator attachment on a natural tooth can be an alternative method in prosthodontic rehabilitation of a partially edentulous adult patient with a distinct approach to meet the needs, esthetics, and psychological well-being of the patient.
  • Comparison of cooling methods on denture base adaptation of rapid heat-cured acrylic using a three-dimensional superimposition technique
    Jacob John, LeeWei May, LimGhee Seong, ZubaidahZanul Abidin, Norliza Ibrahim, et al.
    Journal of Indian Prosthodontic Society, 2021
    Aim: To investigate the effect of different cooling methods on denture base adaptation of rapid heat-cured acrylic resin using 3D superimposition technique. Setting and Design: In vitro - Comparative study. Materials and Methods: Denture base adaptation of two different rapid heat-cured polymethyl methacrylate acrylic resins using five different cooling methods were compared. Forty maxillary edentulous stone cast were prepared to produce the denture bases with standardized thickness. The specimens were divided into five groups (n = 8) according to type of materials and cooling methods. The master stone cast and all forty denture bases were scanned with 3Shape E1 laboratory scanner. The scanned images of each of the denture bases were superimposed over the scanned image of the master cast using Materialize 3-matic software. Three dimensional differences between the two surfaces were calculated and color surface maps were generated for visual qualitative assessment. Statistical Analysis Used: Generalized Linear Model Test, Bonferroni Post Hoc Analysis. Results: All bench-cooled specimens showed wide green-colored area in the overall palatal surface, while the rapid cooled specimens presented with increased red color areas especially at the palate and post dam area. Generalized Linear Model test followed by Bonferroni post hoc analysis showed significant difference in the root mean square values among the specimen groups. Conclusion: Samples that were bench cooled, demonstrated better overall accuracy compared to the rapid cooling groups. Regardless of need for shorter denture processing time, bench cooling of rapid heat-cured PMMA is essential for acceptable denture base adaptation.
  • Dimensional Stability of Elastomeric Impression Material After Disinfection Via Immersion and Microwave Irradiation
    Noorhayati R. Mohd, Ros A. Omar, Enas A. Etajuri
    Open Dentistry Journal, 2021
    Aims: This study aimed to evaluate and compare the dimensional stability of two elastomeric impression materials, namely polyvinyl siloxane (PVS) and vinyl siloxanether (VSE), subjected to chemical immersion and microwave irradiation for disinfection. Materials and Methods: Sixty discs of PVS and VSE impression materials each were prepared using a stainless-steel test die and ring in accordance with ANSI/ADA Specification No. 19. Twenty discs of each impression material were disinfected by chemical immersion for 10 min; another 20 discs were subjected to dry microwave irradiation for 3 min. The other 20 discs served as a control group. Dimensional stability measurements were then performed using an image analyzer at 20× magnification. The data were analyzed by one-way analysis of variance (α=0.05) and Bonferroni (post hoc) test for multiple comparisons to detect significant differences between the groups. Results: When subjected to microwave irradiation, both PVS and VSE showed dimensional changes, but the changes were within the limit of 1.5% set by ANSI/ADA (P<0.00). VSE showed markedly better results than PVS for both disinfection methods. The immersion disinfection method resulted in a higher average percentage of linear dimensional changes than both the microwave irradiation and the control for VSE and PVS impression materials. Conclusion: VSE exhibited excellent dimensional stability than PVS under both chemical immersion and microwave irradiation. Microwave irradiation using conventional microwave ovens can be used in clinical settings as an alternative to other disinfection techniques because the dimensional changes of the elastomeric impression materials subjected to microwave irradiation have been observed to be within the clinically acceptable limit set by the ANSI/ADA standard.
  • Rehabilitation of bilateral cleft lip and palate in adult patient with modification of maxillary overlay cobalt chromium obturator
    International Journal of Dentistry and Oral Science, 2020
  • Deviation of dental implants placed using a novel 3d-printed surgical guide: An in vitro study
    Enas Etajuri, Eshamsul Suliman, Wan Adida Azina Mahmood, Norliza Ibrahim, Muaiyed Buzayan, et al.
    Dental and Medical Problems, 2020
    BACKGROUND There is very little literature available on the reliability of the rapid prototyping technology in the production of three-dimension (3D)-printed surgical guides for accurate implant placement. OBJECTIVES The aim of the study was to evaluate the deviation of implant placement performed with a surgical guide fabricated by means of the rapid prototyping technique (the PolyJet™ technology). MATERIAL AND METHODS Twenty sheep mandibles were used in the study. Pre-surgical cone-beam computed tomography (CBCT) scans were acquired for the mandibles by using the Kodak 9000 3D cone-beam system. Two implants with dimensions of 4 mm in diameter and 10 mm in length were virtually planned on the 3D models of each mandible by using the Mimics software, v. 16.0. Twenty surgical guides were designed and printed using the PolyJet technology. A total of 40 implants were placed using the surgical guides, 1 on each side of the mandible (2 implants per mandible). The post-surgical CBCT scans of the mandibles were performed and superimposed on the pre-surgical CBCT scans. The amount of deviation between the virtually planned placement and the actual implant placement was measured, and a descriptive analysis was done. RESULTS The results showed that the mean deviation at the implant coronal position was 1.82 ±0.74 mm, the mean deviation at the implant apex was 1.54 ±0.88 mm, the mean depth deviation was 0.44 ±0.32 mm, and the mean angular deviation was 3.01 ±1.98°. CONCLUSIONS The deviation of dental implant placement performed with a 3D-printed surgical guide (the PolyJet technology) is within the acceptable 2-millimeter limit reported in the literature.