Lasminda Syafiar
Departemen Ilmu Material Kedokteran Gigi Fakultas Kedokteran Gigi Universitas Sumatera Utara

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Pengaruh Desinfeksi Energi Microwave Terhadap Kekuatan Transversal Resin Akrilik Polimerisasi Panas Sefty Aryani Harahap; Lasminda Syafiar; Yosepha Yulinda Esdaria Lubis
Jurnal Material Kedokteran Gigi Vol 8 No 1 (2019): JMKG Vol 8 No 1 Maret 2019
Publisher : Ikatan Peminat Ilmu Material dan Alat Kedokteran Gigi (IPAMAGI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32793/jmkg.v8i1.363

Abstract

Disinfectant by microwave energy is highly recommended as a solution to solve the problem of chemical disinfection on denture bases. One of the denture base materials is heat cured acrylic resin. Aim, to evaluate the effect of disinfectant by microwave energy with different time on the transversal strength of heat cured acrylic resin. 30 plates (n = 6) of heat cured acrylic resin with size 65x10x2,5 mm were divided into 5 groups (control; and microwave energy disinfected for 2, 4 , 6, and 8 minutes with 650 Watts of power). Transversal strength test was carried out using Torsee's Electronic System Universal Testing Machine with a test speed of 0.1 mm / second, and a load cell of 50 kgf. Data analyzed using one-way ANOVA and LSD pos hoc. Results, there were significant differences in the transverse strength among all groups (p <0.05). Mean values of all groups were 103.59 ± 0.66 MPa; 112.02 ± 2.10 MPa; 117.48 ± 1.73 MPa; 125.46 ± 2.25 MPa; and 135.89 ± 1.56 MPa respectively. Conclusion, the longer it is disinfected by microwave energy, the higher the transversal strength of heat cured acrylic resin.
Kekuatan Transversal Termoplastik Nilon, dan Campuran Resin Akrilik Polimerisasi Panas dan Serat Kaca Lasminda Syafiar; Sefty Aryani Harahap; Richard Salim
Jurnal Material Kedokteran Gigi Vol 9 No 1 (2020): JMKG Vol 9 No 1 Maret 2020
Publisher : Ikatan Peminat Ilmu Material dan Alat Kedokteran Gigi (IPAMAGI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32793/jmkg.v9i1.436

Abstract

Heat cured acrylic resin which is often used as a base for dentures has the disadvantage of being easily broken, the use of flexible denture materials made of nylon thermoplastic has become a new innovation to increase strength. Aim this research to evaluate transversal strength between 1 wt% glass fiber added heat cured acrylic resin and nylon thermoplastic. Thirty two specimens (n=16) with size 65x10x2,5 mm were divided into 2 groups (Nylon termoplastic, and 1 wt% glass fiber added to heat cured acrylic resin). Transversal strength was tested using Torsee’s Electronic System Universal Testing Machine with a load cell of 50 kgf and a test speed of 0.1 mm / second. Statistical data analyzed with unpaired t-test. Results, transversal strength mean value of glass fiber 1 wt% added heat cured acrylic resin was 104,03±9,29 MPa, while nylon termoplastic was 313,89±27,44 MPa. There was statistically significant transversal strength difference between both of groups (p <0.05). Conclusion, It can be concluded that nylon termoplastic had higher transversal strength than 1 wt% glass fiber added heat cured acrylic resin.
Color Changes Of Discolored Human Teeth After Immersion In Spinach Extract In Different Durations Sefty Aryani Harahap; Lasminda Syafiar; Kristin Halim
Sriwijaya Journal of Dentistry Vol. 3 No. 1 (2022): Sriwijaya Journal of Dentistry
Publisher : Dentistry Study Program, Faculty of Medicine Universitas Sriwijaya 

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (241.963 KB) | DOI: 10.32539/sjd.v3i1.23

Abstract

Introduction: Recently, natural dental bleaching agents are being developed to replace chemical dental bleaching agents. Chemical dental bleaching agents containing hydrogen peroxide have the potential to cause toxicity as a side effect. Spinach leaves are natural ingredients that contain oxalic acid which can whiten teeth. Purpose: To investigate the color changes in discolored human teeth after immersion in spinach extract in different durations. Methods: 30 human premolar samples were divided into 3 groups, group A (immersion in 28 hours), group B (immersion in 42 hours), and group C (immersion in 56 hours). All 30 samples were discolored with coffee solution for 12 days and color status (L1, a1, b1) were measured using the chromameter. Then, each 10 samples were immersed in spinach extract according to their treatment group, and the color status (L2, a2, b2) were measured again. Color changes (∆E) were calculated with a formula concerning L, a, b data measured. Results: A significant color change is observed between group A, group B, and group C (p-value= 0.002), and further comparison between three groups showed that group A differed significantly with group C (p-value=0.000), group B also showed significant difference with group C (p-value=0.038). However, there was no significant difference between group A and group B (p-value=0.121). Conclusion: The significant color changes can only be observed after 56 hours of immersion. The spinach leaf extract has the potential to be used as a natural dental bleaching agent.