Mahalakshmi Vijayaraghavan

Dr. Mahalakshmi Vijayaraghavan

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

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

Representative Publications

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29 July 2025 in Journal of Dentistry
Verified
Journal Article
Open access
BABennett Amaechi
Bennett Amaechi
ATAlexandria Isabella Tan
Alexandria Isabella Tan
ANAmal Ahmed K. Noureldin
Amal Ahmed K. Noureldin
Kannan KanthaiahKannan Kanthaiah
Kannan Kanthaiah
EHEmily Holladay
Emily Holladay
MVMahalakshmi Vijayaraghavan
Mahalakshmi Vijayaraghavan
Previous studies has shown that hydroxyapatite (HAP) in oral care formulations could serve as a favorable fluoride alternative for caries management. The present study compared the efficacy of different hydroxyapatite-containing toothpastes in remineralizing early caries lesions. Early enamel caries lesion were produced on one hundred and sixty bovine enamel blocks by 3-day demineralization using a multispies microbial caries model. Following this, the 160 lesion-bearing blockswere randomly assigned to eight treatment groups (20/group): Crest cavity protection (1100 ppm fluoride), ClinPro 5000 (5000 ppm fluoride), Fygg (20 % nanoXIM), Boka (nanoXIM; concentration not disclosed), Dr. Jen (10 % nanoHAP), Risewell Regular (10 % microHAP), Risewell PRO (5 % nanoXIM + microHAP), and Just-Ingredients Powder (15 % microHAP). The blocks were subjected to remineralization by daily pH-cycling consisting of a 2-minute acidic challenge, three 2-minute toothpaste treatments, and then storage in artificial saliva for the rest of the time for 14 days. Surface microhardness (SMH) of each lesion was measured before and after remineralization. Data was analyzed statistically (α = 0.05) by paired t-test (intragroup comparisons) and ANOVA/Tukey tests (intergroup comparison). Every product achieved significant (p < .001) increase in SMH (remineralization). Tukey multiple comparison test indicated that Fygg (39.81 ± 24.07; 95 %CI 26.99-52.64) had a statistically significantly higher percentage remineralization than Boka (19.5 ± 10.56; 95 %CI 14.25-24.75, p < .01), Dr. Jen (21.68 ± 6.72; 95 %CI 18.45-24.92, p < .05), and Risewell Regular (21.80 ± 7.88; 95 %CI 18.11-25.49, p < .05), but did not differ significantly from the other products. There were no significant differences in the percentage remineralization among the rest of the toothpastes. Within the limits of this in vitro study, there are differences in the ability of HAP toothpastes to enhance remineralization of early enamel caries lesions. It demonstrated that combining nanoXIM and nanoHAP in a toothpaste significantly enhanced the effectiveness of HAP to remineralize early caries lesion.

6 June 2025 in Oral
Verified
Journal Article
Open access
PDF file
Chase David HardyChase David Hardy
Chase David Hardy
BABennett Amaechi
Bennett Amaechi
Kannan KanthaiahKannan Kanthaiah
Kannan Kanthaiah
AOAmos Obiefuna
Amos Obiefuna
MVMahalakshmi Vijayaraghavan
Mahalakshmi Vijayaraghavan
SDStanislaus Dyda
Stanislaus Dyda
Objective: This study evaluated the efficacy of a novel interproximal fluoride delivery device, Cav-Aid®, in remineralizing initial proximal caries, comparing it with conventional fluoride treatments. Methods: Initial caries lesions were produced on bovine enamel blocks by subjecting the blocks to a 3-day demineralization process by plaque growth in a mixed-species microbial caries model. After demineralization, the baseline surface microhardness (SMHb) was measured. The blocks were embedded into cavities prepared on the proximal surfaces of extracted human teeth to simulate natural interproximal contacts. The teeth were randomly assigned to six treatment groups (20/group): artificial saliva (AS), Cav-Aid® only (CA), Cav-Aid®/fluoride toothpaste (CA+F), fluoride varnish applied via flossing (FV-Floss), fluoride varnish applied via painting on the interdental cleavage (FV-Paint), and daily fluoride mouthrinse (F-Mouthrinse). The samples then underwent a 14-day pH cycling protocol to simulate remineralization conditions. The post-treatment SMH (SMHr) was measured. Statistical analysis comprised paired t-tests and ANOVA/Tukey’s post hoc comparisons (p < 0.05). Results: All fluoride-treated groups exhibited significant increases in SMHr compared with SMHb (p < 0.001). CA+F group showed the highest percentage remineralization (27.39%), followed by CA (22.16%), then the FV and mouthrinse groups (9.25–11.80%). The AS group exhibited the lowest remineralization (4.89%). CA+F demonstrated significantly greater remineralization than FV or mouthrinse (p < 0.05). However, there was no significant difference between CA alone and CA+F. Also, there was no significant difference between CA alone and FV-Floss or FV-Paint (p > 0.05). Conclusions: Within the limit of the present study, the Cav-Aid® targeted fluoride delivery system demonstrated greater efficacy than FV alone in interproximal remineralization. Dual-modality fluoride treatments (CA+F) provided the greatest remineralization benefits, highlighting the importance of sustained fluoride exposure.

30 April 2025 in Dentistry Journal
Verified
Journal Article
Open access
PDF file
BABennett Amaechi
Bennett Amaechi
Kannan KanthaiahKannan Kanthaiah
Kannan Kanthaiah
RFRayane Farah
Rayane Farah
KYKelly Yang
Kelly Yang
AOAmos Obiefuna
Amos Obiefuna
MVMahalakshmi Vijayaraghavan
Mahalakshmi Vijayaraghavan
Background/Objectives: Dentifrice tablets are a new over-the-counter dentifrice form that are gaining global interest. The aim of this microbial study was to investigate the effectiveness of a dentifrice tablet (DT) containing nanohydroxyapatite (nHAP) to prevent tooth demineralization. Methods: 120 bovine tooth blocks were randomly assigned to four treatment groups (30/group): Nanohydroxyapatite DT (5% nHAP), placebo DT (Placebo), NaF toothpaste (1100 ppm Fluoride) and no-treatment (Control). Blocks were subjected to 7-day demineralization by plaque growth in a mixed-organism Microbial Caries Model. Toothpaste was made into slurry (1 toothpaste:3 water), while DT was thoroughly crushed and homogenized with water (1 tablet:3 water) to slurry. Both slurries were applied twice daily for 2 min on each occasion. Demineralization was assessed using Surface Microhardness (SMH) testing before and after plaque exposure. Change (ΔSMH) and percentage change (%∆SMH) in SMH (percentage demineralization [%Dem]), and % demineralization inhibition (%Dem-Inhibition) in each group were calculated. Intra-group (SMH) comparison (paired t-test) and intergroup (%∆SMH) comparison (ANOVA/Tukey’s test) were conducted (α = 0.05). Results: The paired t-test indicated a significant difference (p < 0.001) between pre-treatment and post-treatment SMH in all groups. The intergroup comparison based on their %Dem using ANOVA/Tukey’s test showed that Control (29.93 ± 5.58) had significantly (p < 0.05) higher %Dem than Placebo (22.81 ± 7.47, p < 0.05), nHAP (13.93 ± 11.31, p < 0.001) and Fluoride (14.44 ± 10.65, p < 0.001). The Placebo had significantly (p < 0.01) higher %Dem than nHAP and Fluoride. No significant difference between nHAP and Fluoride. Intergroup comparison based on their %Dem-Inhibition (calculated relative to the control) using ANOVA/Tukey’s test, nHAP (51.74 ± 40.05, p < 0.01) and Fluoride (50.56 ± 37.21, p < 0.05) had significantly higher %Dem-Inhibition than Placebo tablet (21.86 ± 5.55). No significant difference in %Dem-Inhibition between nHAP and Fluoride. Conclusions: The present study demonstrated that dentifrice tablets containing 5% nanohydroxyapatite are as effective as NaF toothpastes containing 1100 ppm fluoride in preventing tooth demineralization.

1 July 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
ADAlexis DuDash
Alexis DuDash
BABennett Amaechi
Bennett Amaechi
AOAmos Obiefuna
Amos Obiefuna
SASima Abdollahi
Sima Abdollahi
TGTejal Gohil
Tejal Gohil
MVMahalakshmi Vijayaraghavan
Mahalakshmi Vijayaraghavan
Background/Objectives: The present study investigated the effects on the mechanical and physical properties of PMMA when organoselenium was incorporated into it as antifungal at different concentrations. Methods: 141 PMMA rectangle samples were fabricated using a heat compression packing technique and assigned to 3 experimental groups (47/group): 0% organoselenium (control), 0.5% organoselenium (0.5% SE), and 1% organoselenium (1% SE). Each sample was post-processed and stored in water. A three-point bend test was performed to assess elastic modulus and flexural stress. Scanning electron microscopy (SEM) was used to examine the exterior and interior surface topography. Data were analyzed using one-way ANOVA with Tukey’s multiple comparisons test. Results: The mean flexure stress for the 0% samples was statistically significantly higher than those of the 0.5% samples and the 1% samples (p<.001). The mean elastic modulus for the 0% group was statistically significantly higher than those of the 0.5% group and the 1% group (p<.001). Under SEM, the 0.5% samples were smoother with fewer voids and irregularities. Conclusions: The incorporation of organoselenium into PMMA denture base negatively affected its physical and mechanical properties.

19 March 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
BABennett Amaechi
Bennett Amaechi
Kannan KanthaiahKannan Kanthaiah
Kannan Kanthaiah
RFRayane Farah
Rayane Farah
KYKelly Yang
Kelly Yang
AOAmos Obiefuna
Amos Obiefuna
MVMahalakshmi Vijayaraghavan
Mahalakshmi Vijayaraghavan
Background/Objectives: Dentifrice tablets are a new over-the-counter dentifrice form that are gaining global interest. The aim of this microbial study was to investigate the effectiveness of dentifrice tablet (DT) containing nanohydroxyapatite (nHAP) to prevent tooth demineralization. Methods: 120 bovine tooth blocks were randomly assigned to four treatment groups (30/group): Nanohydroxyapatite DT (5% nHAP), placebo DT (Placebo), NaF toothpaste (1100ppm Fluoride), and no-treatment (Control). Blocks were subjected to 7-day demineralization by plaque growth in a mixed-organism Microbial Caries Model. Toothpaste was made into slurry (1 toothpaste:3 water), while DT was thoroughly crushed and homogenized with water (1 tablet:3 water) to slurry. Both slurries were applied twice daily for 2 minutes on each occasion. Demineralization was assessed using Surface Microhardness (SMH) testing before and after plaque exposure. Change (ΔSMH) and percentage change (%∆SMH) in SMH (percentage demineralization [%Dem]), and % demineralization inhibition (%Dem-Inhibition) in each group were calculated. Intra-group (SMH) comparison (paired t-test) and intergroup (%∆SMH) comparison (ANOVA/Tukey’s test) were conducted (α=0.05). Results: Paired t-test indicated significant difference (p<.001) between pre-treatment and post-treatment SMH in all groups. Intergroup comparison based on their %Dem using ANOVA/Tukey’s test showed that Control (29.93±5.58) had significantly (p<.05) higher %Dem than Placebo (22.81±7.47, p<.05), nHAP (13.93±11.31, p<.001), and Fluoride (14.44±10.65, p<.001). Placebo had significantly (p<.01) higher %Dem than nHAP and Fluoride. No significant difference between nHAP and Fluoride. Intergroup comparison based on their %Dem-Inhibition (calculated relative to the control) using ANOVA/Tukey’s test, nHAP (51.74±40.05, p<.01) and Fluoride (50.56±37.21, p<.05) had significantly higher %Dem-Inhibition than Placebo tablet (21.86±5.55). No significant difference in %Dem-Inhibition between nHAP and Fluoride. Conclusions: The present study demonstrated that dentifrice tablets containing 5% nanohydroxyapatite are as effective as NaF toothpastes containing 1100 ppm fluoride in preventing tooth demineralization.

12 November 2025 in Prosthesis
Verified
Journal Article
Open access
PDF file
ADAlexis DuDash
Alexis DuDash
BABennett Amaechi
Bennett Amaechi
AOAmos Obiefuna
Amos Obiefuna
SASima Abdollahi
Sima Abdollahi
TGTejal Gohil
Tejal Gohil
MVMahalakshmi Vijayaraghavan
Mahalakshmi Vijayaraghavan
Background/Objectives: The present study investigated the effects on the mechanical and physical properties of PMMA when organoselenium was incorporated into it as antifungal at different concentrations. Methods: 141 PMMA rectangle samples were fabricated using a heat compression packing technique and assigned to 3 experimental groups (47/group): 0% organoselenium (control), 0.5% organoselenium (0.5% SE), and 1% organoselenium (1% SE). Each sample was post-processed and stored in water. A three-point bend test was performed to assess elastic modulus and flexural stress. Scanning electron microscopy (SEM) was used to examine the exterior and interior surface topography. Data were analyzed using one-way ANOVA with Tukey’s multiple comparisons test. Results: The mean flexure stress for the 0% samples was statistically significantly higher than those of the 0.5% samples and the 1% samples (p < 0.001). The mean elastic modulus for the 0% group was statistically significantly higher than those of the 0.5% group and the 1% group (p < 0.001). Under SEM, the 0.5% samples were smoother with fewer voids and irregularities. Conclusions: The incorporation of organoselenium into PMMA denture base negatively affected its physical and mechanical properties.