Soft Lining Materials Research Articles

Comparative Analysis of Properties in Chairside Silicone Denture Liners versus Heat-Cured Molloplast-B: An In-Depth In Vitro Evaluation.

BACKGROUND We investigated the bond strength, tensile strength, and water absorption properties of 4 widely used chairside silicone long-term denture soft lining materials and compared properties with those of heat-cured silicone material. MATERIAL AND METHODS Four chairside materials (GC Reline Soft, Mucopren Soft, Sofreliner Soft, and Elite Soft Relining) and a heat-cured silicone material (Molloplast B) were investigated. For tensile and shear bond strength and tensile strength, samples were prepared according to the manufacturers' instructions and the testing machine used. For water absorption, IOS 1567 was followed to prepare specimens. Bond strengths were measured using a Lloyd Instruments materials testing machine. Ten specimens for each test were prepared for each soft liner, except for water absorption and solubility tests, for which only 5 specimens were prepared. ANOVA, Bonferroni, and Kruskal-Wallis tests were used to compare values of materials and assess changes over time. RESULTS There was strong evidence of differences in the properties between materials. GC Reline Soft showed comparable tensile bond (1.4±0.6 MPa), shear bond (1.1±0.4 MPa), tensile strength (5.44±0.98), water absorption (0.92±0.2 µg/mm³), and solubility values (0.3±0.2 µg/mm3) to that of Molloplast B (1.4±0.4; 1.6±0.5; 4.53±0.9 MPa, 1.7±0.3, and 1.0±0.3 µg/mm³, respectively). The water solubility of Sofreliner Soft was significantly lower (1.5±0.8 µg/mm³) than that of Molloplast B. CONCLUSIONS There were significant differences between some properties of 4 chairside denture soft lining materials and that of Molloplast B, which had higher shear and tensile bond strength than chairside denture silicone soft lining materials but had the highest water solubility.

In vitro comparative assessment of the denture cleansers effectiveness on the surface hardness of permanent silicone denture line

The purpose of the current research was to evaluate the impact of various denture cleaners on the surface hardness of permanent silicone denture lines. In the present study, 124 specimens were included comprising of soft liners made of permanent silicone, which were made from the 15 mm x 10 mm custom metal mold dimensions, where 62 samples were made of Molossil™ and 62 other of Voco™ which are commercially available liners for permanent dentures. These samples were then divided into 4 groups of equal specimen numbers (n=32) depending on the cleansing treatments. Group I specimens were cleaned with water daily, and Group II Polident™ Group III was given SecureTM denture cleaning solution, while Group IV was given PeriogardTM denture cleaning solution. The samples were assessed at 1st week, 1st month, and 6th month after cleanser use. The study results showed that at the 6th-month follow-up after the use of denture cleansers, all of the samples had considerably increased surface hardness compared to the baseline. Statistically significant results were seen with Periogard™, Secure™, and Polident™ compared to Group I controls. In Voco™ denture liners, minor changes were seen compared to Molossil™ soft liners with time in all the groups. The results of this investigation are significantly well cleansing action is seen with Voco™ soft denture lining material compared to Mollosil™ soft denture lining material, and surface hardness is least affected by Polident™ denture cleanser compared to Secure™ and Periogard™ denture cleansing agents.

Yumuşak Astar Materyallerinin Dental Kaide ile Olan Bağlantısı: Meta Analizi

Background: One of the biggest disadvantages of soft lining materials is that they deform over time and cause ruptures and fractures in the bonding with the denture base. To overcome these problems, the factors that weaken the bonding should be determined and measures should be taken accordingly. The aim of this study is to elucidate the factors affecting the bonding of soft lining materials to the denture base, in terms of dental base and soft lining materials, surface treatments and retention agents.
 Methods: The keywords 'soft lining materials, dental base, bond strength' were written and searched using PubMed/Medline databases, and as a result, 54 research articles related to the current study were evaluated. Each article was classified in terms of the type of denture base and soft lining material, methods of surface treatment, retention agents, and bond strength. 
 Results: While retention in saliva and water bathing decreased the shear bond strength compared to the group without any retention agent, the application of cleaning agents increased the shear bond strength. The tensile bond strength varied according to the surface treatments, and the laser application showed the highest tensile bond strength. In terms of peel strength, the heat-treated group and the laser with chemical treatment applied group showed lower bond strength than the mechanical treatment and soaked group.
 Conclusion: It was concluded that cleaning agents, laser application and mechanical treatments increased the tensile, shear and peel strength.

Effect of Ionic Liquids on Mechanical, Physical, and Antifungal Properties and Biocompatibility of a Soft Denture Lining Material.

This study aims to evaluate the effect of ionic liquids and their structure on the mechanical (tensile bond strength (TBS) and Shore A hardness), mass change, and antifungal properties of soft denture lining material. Butyl pyridinium chloride (BPCL) and octyl pyridinium chloride (OPCL) were synthesized, characterized, and mixed in concentrations ranging from 0.65-10% w/w with a soft denture liner (Molloplast-B) and were divided into seven groups (C, BPCL1-3, and OPCL1-3). The TBS of bar-shaped specimens was calculated on a Universal Testing Machine. For Shore A hardness, disc-shaped specimens were analyzed using a durometer. The mass change (%) of specimens was calculated by the weight loss method. The antifungal potential of ionic liquids and test specimens was measured using agar well and disc diffusion methods (p ≤ 0.05). The alamarBlue assay was performed to assess the biocompatibility of the samples. The mean TBS values of Molloplast-B samples were significantly lower (p ≤ 0.05) for all groups except for OPCL1. Compared with the control, the mean shore A hardness values were significantly higher (p ≤ 0.05) for samples in groups BPCL 2 and 3. After 6 weeks, the OPCL samples showed a significantly lower (p ≤ 0.05) mass change as compared to the control. Agar well diffusion methods demonstrated a maximum zone of inhibition for 2.5% OPCL (20.5 ± 0.05 mm) after 24 h. Disc diffusion methods showed no zones of inhibition. The biocompatibility of the ionic liquid-modified sample was comparable to that of the control. The addition of ionic liquids in Molloplast-B improved the liner's surface texture, increased its hardness, and decreased its % mass change and tensile strength. Ionic liquids exhibited potent antifungal activity.

Tensile Bond Strength between Different Denture Base Materials and Soft Denture Liners.

(1) Background: Various materials are available for CAD-CAM denture base fabrication, for both additive and subtractive manufacturing. However, little has been reported on bond strength to soft denture liners. Therefore, the aim of this study was to investigate tensile bond strength, comparing between different denture base materials and soft denture liners. (2) Methods: Seven different materials were used for denture base fabrication: one heat-polymerized polymethyl methacrylate, three materials for subtractive manufacturing, two materials for additive manufacturing and one polyamide. Two materials were used for soft denture lining: one silicone-based and one acrylate-based. The study was conducted according to the specification ISO No. 10139-2:2016, and the type of failure was determined. The Kruskal-Wallis test with Dunn's post hoc test was used to analyse the values of tensile bond strength, and Fisher's exact test was used to analyse the type of failure. p Values < 0.05 were considered statistically significant. (3) Results: The tensile bond strength values were not statistically significantly different combining all the materials used for denture base fabrication with the acrylate-based soft denture liner (p > 0.05), and the average values ranged between 0.19 and 0.25 Mpa. The tensile bond strength values of the different denture base materials and silicone-based denture liner were statistically significantly different (p < 0.05), and the average values ranged between 1.49 and 3.07 Mpa. The type of failure was predominantly adhesive between polyamide and both additive-manufactured denture base materials in combination with the acrylate-based soft liner (p < 0.05). (4) Conclusions: The use of digital technologies in denture base fabrication can have an influence on different tensile bond strength values for soft denture liners, with different types of failure when compared with heat-cured PMMA. Similar tensile bond strength values were found between the acrylate-based soft denture liner and denture base materials. Significant differences in tensile bond strength values were found between the silicone-based soft denture liner and denture base materials, where the additive-manufactured and polyamide denture base materials showed lower values than heat-cured PMMA and subtractive-manufactured denture base materials.

The Effect of Surface Treatments on The Bonding Strength of the Base Material and The Soft Lining Material

ÖZ Amaç: Yumuşak astar maddeleri, esneklik özellikleri ve yumuşak yapılarından dolayı tam ve bölümlü protezlerde sert protez kaide maddelerinin destek dokular üzerindeki olumsuz etkilerinin önlenmesi veya azaltılması amacıyla kullanılırlar. Zamanla sertleşerek esnekliklerini yitirme, bakteri ve mantar kolonizasyonuna neden olma, porözite gösterme, su absorbe etme, renk değiştirme, protez kaidesinden ayrılma ve protezlerin kırılmaya karşı dayanıklılıklarını azaltma gibi klinik kullanım sürelerini sınırlayan önemli dezavantajlara sahiptirler. Bu nedenle çalışma, polimetil metakrilat (PMMA) esaslı protez kaide maddesi ile yumuşak astar materyali arasındaki bağlanma dayanımına yüzey işlemlerinin etkisinin incelenmesi amacıyla yapıldı. Gereç ve Yöntemler: Çalışmada ASTM D 638-08 standardından faydalanılarak 60 mm uzunluğunda, kalın olan bölümü 15 mm, ince olan bölümü ise 2,5 mm çapında olacak şekilde konvansiyonel sıcak akrilik rezinden 32 örnek hazırlandı. Örnekler rastgele numaralandırılarak dört gruba ayrıldı. Ortadan ikiye ayrılan örneklere farklı yüzey işlemleri (kontrol, kumlama, Er: Yag lazer ve monomer uygulama) uygulandıktan sonra silikon esaslı yumuşak astar maddesi üreticinin önerdiği şekilde uygulandı. Hazırlanan örnekler 37°C distile suda 24 saat bekletildikten sonra bağlanma dayanımları Universal test cihazında değerlendirildi. Verilerin istatistiksel olarak değerlendirilmesi tek yönlü varyans analizi ve çoklu karşılaştırma (Tukey) testi ile yapıldı. Bulgular: Yapılan varyans analizi sonucunda; bağlanma dayanımı üzerinde uygulanan yüzey işlemlerinin çok anlamlı (p&amp;lt;0.001) olduğu saptandı. Sonuç: Protez kaide maddesine yumuşak astar materyalinin daha iyi bağlanmasını sağlamak için protez içerisine yüzey işlemleri uygulanabilir. Anahtar Sözcükler: Bağlanma dayanımı, protez kaide materyali, yumuşak astar maddesi, yüzey işlemi.

Role of Some Natural products as a Disinfectant on Color of GC-SoftLiner

The study aims to evaluate the effect of some natural products (nigella sativa. sesame, flax amd ginger oil) (Emad factory/mosul/Iraq) in relation to nystutin suspension on color of GC-Soft Liner Fifly Sample were prepared frum-GC-extra soft lining material, they were (10*10%2mm). Half of the samples for each group were immersed for 8hr in these oils after they had been infected with Candida albicans and incubated [ur 48hr, the other half of the samples immersed for Bhr daily fur one month. This study compared antifungal efficiency before and after immersion in distilled water (Negative Control), nystatin suspension (100000 LU/ml as a positive control), nigella sativa, sesame, flax and ginger oil. Color of samples tested by Vita — Easy Shade system, the statistical tests used were analysis of variance, Durinet T-test. The resulls demonstrated that there were significant differences between all tested oils znd DW in refution to antifungal action, and no significant differences between all tested oils and D.W iu relation 0 color of GC-solt Lining maternal al (P=0.05). All the tested natural oils were effective antifungal agents and would be accepted and safe in relation to the color of soft hnet.

Assessing the Antifungal Activity of a Soft Denture Liner Loaded with Titanium Oxide Nanoparticles (TiO2 NPs)

Soft denture lining materials are susceptible to be colonized by different microorganisms, especially by Candida albicans (C. albicans), causing denture-induced stomatitis. This study was designed to evaluate the effectiveness of incorporating titanium dioxide nanoparticles (TiO2 NPs) into a soft denture liner towards reducing microbial activity. A total of 40 PEMA-TiO2 nanocomposites samples were fabricated by adding 0.0 wt.% (control), 1.0 wt.%, 1.5 wt.%, and 2 wt.% TiO2 NPs to a heat cured soft denture lining material (polyethyl methacrylate, PEMA). The prepared samples were divided into four groups (n = 10) according to the content of TiO2 NPs. The uniformity of TiO2 NPS distribution within the denture liner matrix was assessed using a Scanning Electron Microscope (SEM). The viable count of C. albicans was evaluated to test the antifungal resistance of the developed composite. The SEM images showed fairly homogeneous dispersion, with patches of TiO2 NPs agglomeration within the PEMA matrix and an increasing concentration of NPs with higher NP content. The particle map and EDX analysis confirmed the evidence of the TiO2 NPs. The mean viable count results for the control (0.0 wt.%) and 1.0 wt.%, 1.5 wt.%, and 2 wt.% TiO2 groups were 139.80, 12.00, 6.20, and 1.00, respectively, with a significant difference from the control group (p < 0.05). The antifungal activity also increased with the increase in the concentration of TiO2 NPs. The addition of TiO2 NPs into a heat-cured soft denture liner provided antifungal activity as evidenced by the reduced colonization of C. albicans. The antimicrobial activity of the liner material increased with the increased concentration of TiO2 NPS.

Evaluate and Compare the Hardness and Tensile Bond Strength of a Silicone Soft Lining Material, after Short Term Immersion in Two Different Denture Cleansing Solutions and Water over Varying Time Periods

Background: Background: To evaluate and compare the hardness and tensile bond strength of a silicone soft lining material, after short term immersion in two different denture cleansing solutions and water over varying time periods. Materials &amp; Methods: The study comprised of 3 groups followed by 3 subgroups under each groups of 10 specimens for evaluation of tensile bond strength with heat cure denture base acrylic resin, and 3 groups followed by 3 subgroups under each groups of 10 specimens each for the hardness test of soft liners. Group A: Heat polymerized silicone based resilient liner immersed in denture cleansing solution secure with 700mg of sodium perborate monohydrate, Group B: Heat polymerized silicone based resilient liner immersed in denture cleansing solution clinsodent with 480mg of sodium perborate monohydrate and Group C: Heat polymerized silicone based resilient liner immersed in water. Results: At day 1 and 1 week, Group B showed highest tensile bond strength (1.500.015) and (1.12  0.012) respectively whereas at 1 month, Group C showed highest tensile bond strength (0.96  0.016). Conclusion: A significant difference exists in the tensile bond strength and the hardness values of the soft liner specimen when immersed in water and two different denture cleansing solutions between the periods of immersion.

Impact of Acrylic and Silicone-Based Soft-Liner Materials on Biting Force and Quality of Life of the Complete Denture Wearers: A Randomized Clinical Trial.

This rerandomized clinical trial evaluated the influence of soft liners (SL) on biting force, pain perception, and the oral health-related quality of life (OHRQoL) of complete denture wearers. Twenty-eight completely edentulous patients complaining of ill-fitting lower complete dentures were selected to participate in the study from the Dental Hospital, College of Dentistry, Taibah University. All patients received new complete maxillary and mandibular dentures; then they were randomly divided into two groups (14 patients in each group): the acrylic-based SL group, in which the mandibular denture was lined with an acrylic-based soft liner, and the silicone-based SL group, in which the mandibular denture was lined with a silicone-based soft liner. OHRQoL and maximum bite force (MBF) were assessed in this study before denture relining (baseline), then at one month and three months after relining. The finding showed that both treatment modalities significantly improved the OHRQoL of included patients at one-month and three-month periods compared to baseline records (i.e., dentures before relining) with a statistically significant difference (p < 0.05). However, there is no statistical difference between groups at the baseline, one-, and three-month follow-up periods. Regarding maximum biting force, when acrylic-based SL is compared to silicone-based SL, there is no statistical difference between groups at baseline (75 ± 31 and 83 ± 32 N) and one-month follow-up periods (145 ± 53 and 156 ± 49 N); however, after three months of function, the silicone-based group recorded 166 ± 57 N statistically significant high biting force compared to the acrylic-based group that recorded 116 ± 47 N (p < 0.05). Permanent soft denture liners positively affect maximum biting force, pain perception, and OHRQoL more than conventional dentures. After three months, silicone-based SL outperformed acrylic-based soft liners in maximum biting force, which may indicate better long-term results.

Effect of non-thermal oxygen-DBD plasma treatment on reducing the phthalate leach and in improving the mechanical strength properties of polymethyl methacrylate denture base and denture liner

Phthalates and esters of aromatic carboxylic acids are used as plasticizers in certain denture soft-lining materials and tissue conditioners. The presence of phthalates is of concern, because they may induce undesirable biological effects such as hormonal disorders, reproductive toxicity, hepatocellular tumours, genital disorders owing to a capacity to bind oestrogen receptors. Despite the potential risk posed by phthalates, their use in denture and denture liner is unavoidable due to the lack of efficient substituent material. Varied curing cycles, solvent wash, thermal plasma treatment/curing, etc., are some of the methods used to eliminate the phthalate content. The use of varied curing cycles, thermal plasma curing etc., will harm the polymer matrix of the acrylic denture resulting in further complication of the acrylic-liner interface bond architecture such as increased wettability, formation of pores, formation of gas pockets, micro fractures at the edges, etc. Hence, in order to overcome the above mentioned, curing of the materials under non thermal Oxygen dielectric barrier discharge (NT-O2/DBD) plasma is suggested. Sets of research samples prepared and lined with PDMS liners (as per ISO 178) were treated with NT-O2/DBD plasma. The treated samples were subjected to mechanical strength tests and calorimetric phthalate leach test. The results indicated that NT-O2/DBD plasma reduced the phthalate content remarkably and improved the overall mechanical strength properties when compared to the controls (thermal plasma treated and heat cured samples).

Concept of the defense material system for the security of Indonesian national armed personnel against threats

It is essential to have materials that can support armor systems for the application of body armor composed of anti-ballistic material from coated fibers in trials in order to defend military personnel with better ballistic performance who are lighter against growing threats and conflicts. to support defense-related ballistics. New materials used in personnel protection systems are the subject of this discussion. As ballistic shields, fiber composite materials are currently used due to their light weight and high flexibility. This essay also discusses a thorough analysis of mechanism performance and failure. This study's goal is to advance knowledge about composite material body armor that is covered with a soft spall liner material, which can be used as a model for lightweight, affordable, and safe designs for military troops in times of conflict.

Analyzing SHORE A hardness to assess the durability of soft denture lining materials

Analyzing SHORE A hardness to assess the durability of soft denture lining materials

Anti-microbial effect of Piper betle crude extract and essential oil incorporated into short-term soft lining material

Anti-microbial effect of Piper betle crude extract and essential oil incorporated into short-term soft lining material

Patient Satisfaction and Oral Health-related Quality of Life (ohrqol) of Edentulous People after Mandibular Denture Relining With a Soft-liner Material: A Pilot Study

Background: Oral health-related quality of life indicators have been effectively used to assess the influence of a range of dental treatments and interventions on patient satisfaction and acceptance. Objectives: The purpose of this study was to evaluate the impact of the relining of mandibular dentures with a soft-liner material, using the Oral Health Assessment Index (OHIP-14). Methods: Forty-two full denture wearers were selected from patients who attended 9 private prosthetic clinics in New South Wales, Australia. All participants had their lower dentures relined with a soft-liner material, according to the manufacturer’s instructions. Oral health-related quality of life was evaluated before and 1 month after relining using the Oral Health Assessment Index questionnaire. A simple descriptive quantitative analysis of the survey results was undertaken, including a comparison of median scores using the Wilcoxon paired test and binomial probability test. Results: In all the outcome variables measured, there was a noticeable positive effect from the denture relining. Specifically, mandibular denture relining with a silicon-based soft-liner material has a positive impact on patient satisfaction and oral health-related quality of life (OHRQoL) of edentulous patients. Conclusion: Patient satisfaction and oral health-related quality of life (OHRQoL) of edentulous patients can be significantly improved by the use of soft-liner materials.

Effect Of Incorporation Of Either Neem Or Aloe Vera Powders On Tear Strength And Hardness Of Acrylic Soft Denture Liner Material

Aim of the study: The heat acrylic soft lining materials are far from ideal due to poor soften and weak tearing strengths. This cause some practical problems when testing the adherence of soft liners to denture bases. The study objective was to assess the effect of either Neem or Aloe Vera extracts on tear strength and hardness of heat acrylic soft denture lining material.&#x0D; Materials and methods: Sixty acrylic soft liner specimens were prepared and divided into two main groups (30 specimens for tear strength test, 30 specimens for hardness test). These main groups sub-divided into three groups, each one consist of 10 specimens, according to incorporated material. The hardness specimens were fabrication with dimensions of (30 mm diameter × 3 mm thickness). The tear strength specimens were fabricated according to ASTM specification D-624. The scanning electron microscope (SEM) was used to estimate the distribution of either Neem or Aloe Vera particles within the soft liner. Energy dispersive X-ray spectroscopy (EDS) was used to analysis the elements of studied materials. Tear strength specimens were measured by utilizing universal Instron machine. Hardness specimens were measured by utilizing Shore A durometer. Statically all data were analyzed by using SPSS software.&#x0D; Results: The outcomes showed non-significant differences (p&gt;0.05) of all studied groups in tear strength and a highly significant (p&lt;0.001) decrease in hardness of all studied groups in comparison with the control group.&#x0D; Conclusion: Incorporation of Neem or Aloe Vera extracts powders showed slight increases in tear strength and highly significant decreases in hardness of soft liner material.

The Influence Of Bacteriocin On The Soft Liner Tensile Strength And Its Inhibitory Effect On Candida Albicans

Aim of the study. Many efforts were applied to use new antimicrobial agents due to the recent appearance of bacterial resistance to treatment. One of the antimicrobial agents is the Bacteriocin. Bacteriocins are small molecules produced by probiotics bacteria and have the ability to minimize pathogens colonization. This study performed to evaluate the effect of bacteriocin against candida albicans growth, inhibition of the formation of biofilm and tensile strength of the hot soft liner and compare the results with the use of denture cleanser tablets.&#x0D; Materials and Methods. Two types of specimens were prepared first type to measure the tensile strength for the soft liner and the other type to measure the inhibition of growth and the biofilm of C. albicans. Each type was divided into subgroups (15 specimens each) to be immersed in water as control, Bacteriocin and denture cleansing tablets at different intervals. For the tensile strength test, rectangular hot cure soft denture liner specimens prepared with dimensions of 80mm*9mm*3mm length, width and thickness respectively. While for microbiological test, 10mm diameter and 3mm thick discs of heat cured soft lining material were prepared. The specimens used for the tensile strength test were divided into three groups according to the immersion method: 1st group is the control immersed in water, 2nd group immersed in Bacteriocin and 3rd group immersed in denture cleansing tablet (Lacalut DENT Cleaning tabs/Germany). While for the microbiological test the specimens divided into control group, group treated with bacteriocin for 1 day and group treated with bacteriocin for 15 and 30 days. The same thing done for the specimens cleaned by denture cleansing tablets. The immersion was performed by placing the specimens in tube (10ml) filled with bacteriocin or cleansing tablet in water and kept for 15min. Then the specimens were removed from the tube and cleaned with tapped water and stored in distilled water. This was repeated for 15 days for the first group, and 30 days for the other group. The tensile strength was measured by the Instron testing machine, the inhibition of C.albicans growth and biofilm formation was tested by co-cultured method.

Tensile bond strength of soft and hard relining materials to conventional and additively manufactured denture-base materials.

Studies comparing tensile bond strength of various soft and hard denture liner materials to conventionally and additively manufactured denture base resins are lacking. The purpose of this study was to investigate the tensile bond strength between chair- and laboratory-side soft and hard relining materials and denture-base materials produced by additive manufacturing and conventional methods. A total of 120 dimethacrylate-based additively manufactured and polymethylmethacrylate (PMMA)-based conventionally fabricated dumbbell-shaped denture-base resins were produced. Heat-cured laboratory-side soft reline material, self-cured chair-side soft reline material, and self-cured chair-side hard reline material were attached to the denture bases. The tensile force was applied to the specimens with a universal testing machine at a crosshead speed of 5mm/min. The obtained data were analyzed with two-way ANOVA and post hoc Tukey tests. The significance level was set at α= 0.05. The highest tensile bond strength values were obtained in the specimens from the conventionally manufactured base and self-cured chair-side hard reline material group, and the lowest was seen in the additively fabricated base and self-cured chair-side soft reline material group (p<0.001). Conventionally manufactured base material's tensile bond strength was higher than that of additively fabricated resin, and self-cured chair-side hard reline material's strength was higher than that of laboratory-side and chair-side soft reline materials (p<0.001). However, no significant difference emerged between laboratory-side and chair-side soft reline materials (p= 0.405). All the specimens used in the present study had tensile bonding stress values for clinical use. Both denture base resins provided an increased bond to the chair-side hard relining material, although an improved bond did not emerge for the chair-side and laboratory-side soft denture reline materials.

Evaluating the Effect of Lemongrass Essential Oil Addition on Some Properties of Heat Cure Acrylic Soft-Lining Material

Background: Denture liners’ viscoelasticity absorbs shocks and relieves tissue pressure. Soft liners must be replaced every 6–12 months because oral conditions destroy elastomers. By adding chemicals to soft liners, researchers have created a new class of flexible, oral-friendly materials. This lowers denture and mucosa pressure. Objectives: The aim of the study is to discover if the best two concentrations of lemongrass essential oil (LGEO) added to heat-cured soft denture liner improves the material’s hardness, the strength of the peel bond, and surface roughness. Materials and Methods: In a pilot study, 2.5 vol.% and 5 vol.% LGEO improved the heat-cured soft-liner material’s Shore A hardness and surface roughness. The main study categorized 90 specimens into three groups (Shore A hardness, peel bond strength, and surface roughness). Each of the groups has three subgroups (control, 2.5 vol.% of LGEO additive, and 5 vol.% of LGEO additive). One-way analysis of variance, Dunnett’s T3 post hoc, Tukey’s honestly significant difference, and Fisher’s exact test were used for data analysis, which was significant at P &lt; 0.05. Results: After adding 2.5 vol.% and 5 vol.% of LGEO additives (experimental subgroups), Shore hardness, peel bond strength, and surface roughness of the two experimental subgroups decreased significantly from the control subgroup at P &lt; 0.05, except for 2.5 vol.% of the LGEO additive subgroup, which did not differ significantly at P &gt; 0.05. When failure mode was assessed, all subgroups varied substantially. The 2.5 vol.% of LGEO addition specimens showed adhesive and cohesive failure with some mixed type, whereas 5 vol.% showed predominantly cohesive failure. Conclusions: LGEO enhances the hardness and surface roughness of the soft-lining material, making it more resilient and smoother. This leads to a greater cushioning effect and reduced damage to the oral tissues while decreasing the liner’s peel bond strength to an acceptable level. 5 vol.% is the best percentage that improves liner properties.

Effects of Litsea cubeba Essential Oil Incorporated into Denture Soft Lining Materials.

The antimicrobial properties, cell cytotoxicity and surface hardness of soft lining materials (GC soft liner, Viscogel and Coe comfort) incorporated with various concentrations of Litsea cubeba essential oil (LCEO) were evaluated. The minimum inhibitory concentrations of LCEO against Candida albicans and Streptococcus mutans were 1.25% v/v and 10% v/v, respectively. However, when LCEO was incorporated into the three soft lining materials (GC soft liner, Viscogel and Coe comfort), 10% v/v and 30% v/v of LCEO could inhibit the growth of C. albicans and S. mutans, respectively. The extracts of soft lining materials with 10% and 30% v/v LCEO, 2% chlorhexidine, 30% v/v nystatin and no additive were used for cytotoxicity tests on a human gingival fibroblast cell line. There was no significant difference in cell viability in all groups with additives compared to the no additive group (p > 0.05). Surface hardness increased significantly between 2 h and 7 day incubation times in all groups, including the controls (p < 0.05). A higher LCEO concentration had a dose-dependent effect on the surface hardness of all soft lining materials (p < 0.05). However, the surface hardness of materials with additive remained in accordance with ISO 10139-1. LCEO could be used as a natural product against oral pathogens, without having a negative impact on soft lining materials.