Melissa Rachel Fok

Dr. Melissa Rachel Fok

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 December 2021 in Journal of Clinical Periodontology
Verified
Journal Article
Closed access
PDF file
SUSamantha N. M. R. Uy
Samantha N. M. R. Uy
KDKe Deng
Ke Deng
CFChris Tat Cheun Fok
Chris Tat Cheun Fok
MFMelissa Rachel Fok
Melissa Rachel Fok
GPGeorge Pelekos
George Pelekos
MTMaurizio Tonetti
Maurizio Tonetti

17 July 2023 in Clinical Oral Implants Research
Verified
Journal Article
Open access
GPGeorge Pelekos
George Pelekos
BCBonnie Chin
Bonnie Chin
XWXinyu Wu
Xinyu Wu
MFMelissa Rachel Fok
Melissa Rachel Fok
JSJunyu Shi
Junyu Shi
MTMaurizio Tonetti
Maurizio Tonetti
Background: The shape of implant restorations is critical for function and aesthetics. It may also be important in peri‐implant tissue health preservation. This study aimed to associate the restorative contour of a single crown with marginal dental plaque accumulation, tissue inflammation and probing depths.Methods: Subjects with a single screw‐retained implant restoration were clinically examined. The presence of dental biofilm, tissue inflammation and probing pocket depths were the dependent variables. The emergence angle, profile and depth of the mucosal tunnel were measured on superimposed digital scans of the crown soft‐tissue complex, the removed crown mounted on an analogue and the soft tissue.Results: One hundred twenty two subjects (46.7% female, 68.9% never smokers, 77% with treated periodontitis and 52.5% participating in regular supportive peri‐implant care) were examined. The emergence angles at the mucosal margin were 15.3 ± 9.4°, 12.7 ± 8.5°, 31.3 ± 11.8° and 19.2 ± 9.8° for the mesial, distal, vestibular and oral aspects of the crowns. The largest emergence profile angles were observed on the vestibular aspect (74.6% of cases), reaching a maximum of 61.7°, and profiles were convex in 59% of cases. Generalized estimating equations indicated that the site‐specific platform‐level emergence angle and profile and depth of the mucosal tunnel were significantly associated with the presence of detectable plaque accumulation (p < .01) and bleeding on probing (p < .02).Conclusions: Subtle variations in the shape of the restorative crown are associated with biofilm accumulation and mucosal inflammation. These findings are important for 3D implant planning/positioning and preservation of peri‐implant tissue health.

30 June 2022 in Cells
Verified
Journal Article
Open access
PDF file
XWXuzhu Wang
Xuzhu Wang
MFMelissa Rachel Fok
Melissa Rachel Fok
GPGeorge Pelekos
George Pelekos
LJLijian Jin
Lijian Jin
MTMaurizio Tonetti
Maurizio Tonetti
L-PRF is an autologous blood-derived biomaterial (ABDB) capable of releasing biologically active agents to promote healing. Little is known about its release profile of growth factors (GFs), cytokines, and MMPs. This study reported the in vitro and ex vivo release kinetics of GFs, cytokines, and MMPs from L-PRF at 6, 24, 72, and 168 h. The in vitro release rates of PDGF, TGF-β1, EGF, FGF-2, VEGF, and MMPs decreased over time with different rates, while those of IL-1β, IL-6, TNF-α, IL-8, and IL-10 were low at 6 h and then increased rapidly for up to 24 h and subsequently decreased. Of note, the release rates of the GFs followed first-order kinetics both in vitro and ex vivo. Higher rates of release were found ex vivo, suggesting that significant amounts of GFs were produced by the local cells within the wound. In addition, the half-life times of GFs locally produced in the wound, including PDGF-AA, PDGF-AB/BB, and VEGF, were significantly extended (p < 0.05). This work demonstrates that L-PRF can sustain the release of GFs and cytokines for up to 7 days, and it shows that the former can activate cells to produce additional mediators and amplify the communication network for optimizing the wound environment, thereby enhancing healing.


3 April 2024 in Journal of Dentistry
Verified
Journal Article
Open access
MFMelissa Rachel Fok
Melissa Rachel Fok
LJLijian Jin
Lijian Jin
This review was to offer a comprehensive analysis of currently available evidence on post-extraction alveolar socket healing, including i) the histological and molecular events during alveolar socket healing, ii) the dimensional ridge alterations after socket healing and controversies relating to sinus pneumatisation, iii) the patient-specific factors, procedural elements, and site-related variables influencing socket healing, iv) techniques and effectiveness of alveolar ridge preservation (ARP) procedure, and v) the philosophies and cost-effectiveness of ARP in clinical practice. To investigate the dimensional profiles of the alveolar ridge following unassisted healing, an overview of systematic reviews was conducted in February 2024 by two independent reviewers. Four electronic databases were searched in Pubmed, Embase, Web of science and Cochrane Library between 2004 and 2024 to identify all relevant systematic reviews on post-extraction healing. A further manual search of reviews was also conducted. The articles were further reviewed in full text for relevance. The AMSTAR-2 appraisal tool was adopted to assess methodological quality. Current research pertaining to other listed objectives was objectively analysed in narration. 11 out of 459 retrieved studies were selected and ultimately covered in this review on the dimensional changes of alveolar ridge following natural healing: Seven systematic reviews and four systematic reviews with meta-analyses. The methodological quality of all included reviews was critically low. This review thoroughly examines the healing profiles of post-extraction alveolar sockets and highlights the dynamic process with overlapping phases and the inter-individual variability in outcomes. ARP procedure is a potential strategy for facilitating prosthetic site development, while the current evidence is limited. Herein, an individualised and prosthetically driven approach is crucial. Further well sized and designed trials with novel biomaterials need to be undertaken, and the role of artificial intelligence in predicting healing and assisting clinical decision-making could be explored. By advancing our understanding of alveolar socket healing and its management strategies, clinicians can make more informed decisions regarding patient and site level assessment and selection, surgical techniques, and biomaterial choices, ultimately contributing to the enhanced healing process with reduced complications and improved quality of life for patients undergoing tooth extraction and dental implant treatments.

1 January 2023 in Journal of Prosthodontic Research
Verified
Journal Article
Open access
PDF file
MZMengze Zhang
Mengze Zhang
DHDominic King Lun Ho
Dominic King Lun Ho
GPGeorge Pelekos
George Pelekos
MFMelissa Rachel Fok
Melissa Rachel Fok
Purpose: To investigate survival rates and technical and biological complications of one-piece screw-retained hybrid abutments in implant-supported single crowns (SCs).Study Selection: An electronic search was performed on five databases for clinical studies involving implant-supported single hybrid abutment crowns constructed using titanium-base (Ti base) abutments, with at least 12 months of follow-up. The RoB 2, Robins-I, and JBI tools were used to assess the risk of bias for the different study types. Success, survival, and complication rates were calculated, and a meta-analysis was performed to obtain a pooled estimate. Peri-implant health parameters were extracted and analyzed.Results: 22 records (20 studies) were included in this analysis. Direct comparisons between screw-retained hybrid abutment SCs and cemented SCs showed no significant differences in the 1-year survival and success rates. For SCs using a hybrid abutment crown design, their 1-year survival rate was 100% (95% CI: 100%-100%, I2 = 0.0%, P = 0.984), and a success rate of 99% (95% CI: 97%-100%, I2 = 50.3%, P = 0.023) was calculated. No confounding variables significantly affected the estimates. The individual technical complication rate was low at 1-year follow-up. The estimated incidence of all types of complications in hybrid abutment SCs is less than 1%.Conclusions: Within the limitations of this study, implant-supported SCs using a hybrid abutment crown design showed favorable short-term clinical outcomes. Additional well-designed clinical trials with at least a 5-year observation period are required to confirm their long-term clinical performance.