Influence of new complete dentures on the touch perception threshold and quality of life of edentulous patients.

OBJECTIVE: To evaluate the touch perception threshold of the alveolar mucosa and quality of life of edentulous patients before (T0) and 30 days after (T1) the insertion of new complete dentures. BACKGROUND: Touch perception is important so that edentulous patients can detect the position of complete dentures in their mouth. MATERIALS AND METHODS: This study included 32 complete denture wearers with good oral and systemic health and no temporomandibular disorders for at least 5 years. At each time point (T0 and T1), two tests were performed (touch perception threshold and quality-of-life scale). The touch perception threshold (Von Frey or Semmes-Weinstein test) was assessed using nylon monofilaments on the regions of the alveolar mucosa of the maxilla and mandible. The Oral Health Impact Profile for edentulous individuals (OHIP-EDENT) was administered to evaluate oral health-related quality of life. RESULTS: In the maxilla and mandible, the touch perception thresholds for all regions of the alveolar mucosa were significantly lower at T1 than at T0. The OHIP-EDENT mean scores showed that the overall quality of life was significantly better at T1 (3.6) than at T0 (4.7), and a significant improvement in quality of life was observed in all domains of the OHIP-EDENT at T1. For touch perception threshold, effect sizes ranged from 0.4 to 0.8; and for quality of life, effect sizes ranged from 0.4 to 1.0. CONCLUSIONS: New complete dentures reduced the touch perception threshold of the alveolar mucosa of both edentulous arches and improved individuals' quality of life.

Effect of Extrinsic Pigmentation on Dimensional Stability, Hardness, Detail Reproduction, and Color of a Silicone.

OBJECTIVE: The aim of the study is to evaluate the effect of extrinsic pigmentation on the dimensional stability, hardness, detail reproduction, and color of a silicone after thermocycling. MATERIALS AND METHODS: Sixty samples of MDX4-4210 silicone (Dow Corning Corporation Medical Products) with intrinsic pink pigment (H-109-P, Factor II) and intrinsic opacifier (TiO) were fabricated. Two groups were created: Group 1-only intrinsic pigmentation (H-109P, Factor II + TiO) (Control); and Group 2-intrinsic (H-109P, Factor II + TiO) and extrinsic (Tan FE - 215, Factor II) pigmentation. The following tests were performed for each group: dimensional stability, Shore A hardness, detail reproduction, and color. Readings for the tests were taken before and after thermocycling (2,000 cycles). For dimensional stability and hardness, two-way analysis of variance (ANOVA) was used. One-way ANOVA was used for the color test. In case of significant statistical difference, the Tukey test was applied (p <0.05). All samples achieved the same detail reproduction score, therefore, no statistical evaluation was performed. RESULTS: For the dimensional stability test, comparing the initial time with the final time, there was a significant contraction in both groups after thermocycling. For the hardness test, comparing the time points, only group 1 showed a significant reduction in hardness after thermocycling. Groups 1 and 2 scored 2 for the detail reproduction test, before and after thermocycling. Comparing group 1 with group 2, there was no significant difference for color change. CONCLUSION: Based on the tests performed, extrinsic pigmentation did not show a negative effect on silicone, and therefore it can be indicated. The results of the dimensional, hardness, detail reproduction and color evaluations of the MDX4-4210 silicone were clinically acceptable in all cases in the groups with and without extrinsic pigmentation.

Influence of Different Pigment Incorporation Methods on the Sorption and Solubility of Medical Silicones.

OBJECTIVE: The aim of this study is to verify the influence of three pigment incorporation methods (conventional, mechanical, and industrial) on the sorption and solubility of the MDX4-4210 and A-2186 silicones. MATERIALS AND METHODS: The groups formed were based on the silicones used (A-2186 and MDX4-4210), intrinsic pigments (pink, bronze, and black), and pigment incorporation methods (conventional, mechanical, and industrial). The dimensions of all samples were 45-mm diameter (ø) × 1-mm thickness. Readings were taken initially and after 1,008 hours of aging. STATISTICAL ANALYSIS: Three-way analysis of variance and the Tukey's test were performed (α = 0.05). RESULTS: For sorption and solubility, there was no difference between the incorporation methods for the A-2186 silicone, regardless of the pigment used (p > 0.05). For pink MDX4-4210, the industrial and mechanical methods showed higher values of sorption compared with the conventional method (p < 0.05). For bronze MDX4-4210, the industrial method showed a higher sorption value compared with the conventional and mechanical methods (p < 0.05). For black MDX4-4210, there was no difference between incorporation methods based on sorption (p > 0.05). For pink MDX4-4210, the mechanical method showed a higher solubility value compared with the industrial and conventional methods (p < 0.05). For black MDX4-4210 and bronze MDX4-4210, there was no statistically significant difference between incorporation methods based on solubility (p > 0.05). CONCLUSION: Based on sorption and solubility, for the A-2186 silicone, the conventional, mechanical, and industrial methods of pigment incorporation were equivalent. For the MDX4-4210 silicone, its results of sorption and solubility were varied, and further studies are recommended.

Oral Health-Related Quality of Life, Dry Mouth Sensation, and Level of Anxiety in Elderly Patients Rehabilitated with New Removable Dentures.

OBJECTIVE: This study aimed to evaluate the influence of new complete dentures (CDs) and new removable partial dentures (RPDs) on oral health-related quality of life, dry mouth sensation, and anxiety level of their wearers. MATERIALS AND METHODS: In total, 20 complete edentulous patients (in both arches) that needed to be rehabilitated with new CDs, and 20 partial edentulous patients (in both arches) that needed to be rehabilitated with new RPDs, were included in this study. Each patient must wear the same pair of CDs or RPDs for more than 5 years. Oral health-related quality of life, dry mouth sensation, and level of anxiety were assessed by using the following questionnaires: Geriatric Oral Health Assessment Index (GOHAI), VAS (Visual Analog Scale) Xerostomia Questionnaire, and State-Trait Anxiety Inventory (STAI). These questionnaires were applied before oral rehabilitation (initially initial time point) and 3 months after insertion of new dentures (end time point). STATISTICAL ANALYSIS: For the results of STAI-State, STAI-Trait, and GOHAI, the Wilcoxon test was applied to compare the time points. For the results of the VAS xerostomia questionnaire, two-way repeated measures ANOVA (analysis of variance) was applied, followed by the Tukey test. The p-values lower than 0.05 were considered statistically significant. RESULTS: /CONCLUSION: For both groups, it was observed that 3 months after the insertion of new removable dentures: (1) there was an increase in oral health-related quality of life; (2) there was a reduction in anxiety (trait anxiety and state anxiety); and (3) there was a perception of greater salivation.

Effect of Rehabilitation with a New Ocular Prosthesis on Electromyography of the Occipitofrontalis, Temporal, Masseter, and Sternocleidomastoid.

OBJECTIVES: The aim of this study was to verify during facial expressions ("happy," "sad," "fearful," "angry," "surprised," and "disgusted") if: (1) there would be difference in the electromyography (EMG) of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles on the normal side (NS) compared with the affected side (AS) (without the use of an ocular prosthesis) in individuals with unilateral absence of the eyeball, and (2) the rehabilitation with a new ocular prosthesis would affect the EMG of the muscles studied on the AS in these individuals. MATERIALS AND METHODS: Thirteen individuals, without temporomandibular disorder, with good health, with unilateral absence of the eyeball (the eye must have been removed by evisceration or enucleation), and users or nonusers of an ocular prosthesis were included. EMG of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles was performed during rest and facial expressions ("happy," "sad," "fearful," "angry," "surprised," and "disgusted") before (T0) and 90 days after (T1) rehabilitation with a new ocular prosthesis. The analyses were performed in T0 on NS and AS (without the use of an ocular prosthesis), and in T1 on AS with the new ocular prosthesis. STATISTICAL ANALYSIS: All data were submitted to the Student's t-test with p < 0.05. RESULTS: There was no statistically significant difference comparing the AS with the NS in T0 for all muscles studied, during all facial expressions evaluated (p > 0.05). There was no statistically significant difference comparing the AS in T0 with itself in T1 for all muscles studied, during all facial expressions evaluated (p > 0.05). CONCLUSION: Eye loss did not affect the EMG of studied muscles when comparing NS with AS (without the use of an ocular prosthesis). The rehabilitation with ocular prosthesis was not capable of changing the EMG on AS.

Comparison of Techniques for Obtaining Centric Relation Based on the Reproducibility of the Condylar Positions in Centric Relation-A Systematic Review.

The objective of this systematic review was to compare centric relation (CR) techniques that belong to the same method of obtaining CR (guided, graphical, or physiological method), to verify which CR technique within each method of obtaining CR generates the greatest reproducibility of the condylar positions (or mandibular position) in CR. The PubMed, Cochrane Library, SciELO, Scopus, and Web of Science databases were searched for articles published up to May 5, 2021. The search terms were combinations of "dental centric relation" (MeSH), with each of the following terms (individually): "reproducibility of findings" (MeSH); "jaw relation record" (MeSH); "chin point"; "gothic arch"; "bimanual manipulation"; "swallowing" (MeSH); and "jig." Inclusion criteria: clinical studies in English; individuals without temporomandibular dysfunction and with complete or almost complete dentition or complete edentulous; and comparison between CR techniques belonging to the same method of obtaining CR based on the reproducibility of condylar positions in CR. For each method of obtaining the CR, the following CR techniques were considered: guided method (chin point guidance and bimanual manipulation); graphic method (intraoral and extraoral gothic arch tracing); and physiologic method (swallowing and tongue retrusion along the palate). A total of 1692 articles were screened. After the inclusion and exclusion criteria were applied, six articles were included in this review. None of the included studies evaluated edentulous individuals. All included articles compared CR techniques of the guided method. Three articles concluded that the bimanual technique showed greater reproducibility of the condylar positions in CR than the chin point guidance technique, two articles showed equivalence between these techniques, and 1 article concluded that the chin point guidance technique showed greater reproducibility of the condylar positions in CR than the bimanual technique. Thus, in this systematic review, the bimanual technique was often superior (generated greater reproducibility of the CR) or at least equivalent to the chin point guidance technique. Therefore, for individuals with complete dentition and without temporomandibular disorders, the bimanual technique is more recommended.

Dentistry and Intensive Care Unit: A Brief Report.

OBJECTIVE: The aim of this study is to verify whether removable dentures of patients admitted to an intensive care unit (ICU) are niches of microorganisms that can cause pathologies (Staphylococcus aureus, Candida spp., and enterobacteria). MATERIALS AND METHODS: Fifteen patients who were denture wearers (removable partial denture and complete denture) were included in this study. Patients must wear their dentures daily, and these dentures must have acrylic parts. Microbial biofilm was collected from the acrylic part of one denture of each patient. Then, the biofilm was seeded on different culture media: Sabouraud agar, blood agar, MacConkey agar, and mannitol salt agar. In this study, biochemical evaluations of microorganisms were performed. STATISTICAL ANALYSIS: The percentage of dentures with the microorganism identified by each culture medium was calculated. RESULTS: In total, 100% of the dentures were positive for Staphylococcus spp. (blood agar) and Candida spp. (Sabouraud agar); 33.3% of the dentures were positive for S. aureus (Mannitol salt agar); and 13.3% of the dentures were positive for Shigella spp. (MacConkey agar). CONCLUSION: Removable dentures of patients (removable partial dentures and complete dentures) admitted to an ICU are niches of microorganisms that can cause pathologies.

Influence of thermocycling and disinfection on the color stability and hardness of thermoplastic sheets used for occlusal splint fabrication.

The aim of this study was to compare PETG/TPU (polyethylene terephthalate glycol/thermoplastic polyurethane) with PETG (polyethylene terephthalate glycol), based on color stability and microhardness. Sixty circular specimens (10 mm in diameter × 3 mm thick) were fabricated (30 PETG/TPU and 30 PETG). The specimens in both groups were submitted to 2000 thermal cycles in alternating baths of 60 seconds at 5°C ± 1°C and 55°C ± 1°C. The specimens were then divided into subgroups (n = 10) that were disinfected 15 minutes per day for 60 days in 1 of 3 solutions: liquid soap, 2% chlorhexidine, or Listerine. Color change (∆E*) and Knoop microhardness tests were performed at baseline (T0), after thermocycling (T1), and after disinfection (T2). Analysis of variance (ANOVA) and Tukey test were used (P < 0.05). ANOVA showed that there was no statistically significant difference in color change between the 2 materials after thermocycling (∆E*1) or after disinfection (∆E*2), regardless of the disinfectant. Intragroup comparisons (Listerine, liquid soap, and 2% chlorhexidine) of the 3 PETG/TPU groups or 3 PETG groups after disinfection revealed no statistically significant difference for microhardness. Comparison of PETG/TPU with PETG based on the overall mean microhardness showed that the PETG/TPU had a significantly greater mean surface hardness value (P < 0.05). The Tukey test revealed statistically significant increases in microhardness at T1 and T2 for PETG/TPU and PETG so that T0 < T1 < T2 (P < 0.05). Both thermoplastic materials demonstrated an increase in hardness after thermocycling and after disinfection, and both showed similar color changes regardless of the disinfection method. Based on the color evaluation, the liquid soap proved to be the best option for disinfection of PETG/TPU and PETG, because the color change (∆E* value) was clinically acceptable for both materials.

Comparison of different methods for obtaining centric relation: a systematic review.

The objective of this study was to compare techniques of different methods of obtaining centric relation to verify which technique generates the greatest reproducibility of the centric relation. The PubMed/MEDLINE, Cochrane Library, SciELO, Scopus, and Web of Science databases were searched for articles published up to May 15, 2018. The search terms were combinations of "dental centric relation" with each of the following terms (individually): "reproducibility of findings"; "jaw relation record"; "chin point"; "gothic arch"; "bimanual manipulation"; "swallowing"; and "jig." The inclusion criteria included clinical studies in English that had to compare at least 2 techniques representing different methods for obtaining centric relation (based on the reproducibility of the centric relation) in individuals without temporomandibular dysfunction; and studies performed in individuals with complete or nearly complete dentition or complete edentulism. Methods (techniques) included in this study were guided methods (chin point guidance and bimanual manipulation); graphic methods (intraoral and extraoral gothic arch tracing); and physiologic methods (swallowing and tongue retrusion along the palate). A total of 1638 articles were identified. After the inclusion and exclusion criteria were applied, 7 articles were included in this review. None of the reviewed studies evaluated edentulous individuals. Two articles compared physiologic methods with guided methods; one concluded that the swallowing technique generates greater variability than guided methods, and the other concluded that there was no difference between the swallowing technique and chin point guidance. Of 5 articles comparing intraoral gothic arch tracing with guided methods, 2 showed similar results between different methods, 2 showed superior results for gothic arch tracing, and 1 showed superior results for the guided methods. Based on the guided methods and swallowing technique, it is not possible to conclude which technique can generate the greatest reproducibility of the centric relation. It is possible to suggest that in most cases intraoral gothic arch tracing is superior or equivalent when compared to guided methods.

In vitro evaluation of the effect of different disinfectants on the biofilm of Staphylococcus epidermidis and Staphylococcus aureus formed on acrylic ocular prostheses.

The aim of this study was to evaluate the effect of disinfectants on the biofilm of Staphylococcus aureus and Staphylococcus epidermidis formed on the acrylic surface of ocular prostheses. In this study, 396 acrylic specimens were manufactured (50% for Staphylococcus epidermidis, and 50% for Staphylococcus aureus). For each bacterium, 66 specimens were subjected to biofilm formation on their surfaces for 24 hours, 66 specimens were subjected to biofilm formation on their surfaces for 48 hours, and 66 specimens were subjected to biofilm formation on their surfaces for 72 hours. Then, they were divided into groups according to disinfection method (n = 6): sterile distilled water for 10, 15, 30 min, and 6 hours (control); soap for 30 min (NES30); Opti-Free for 30 min (OPF30) and 6 h (OPF6); Efferdent for 15 min (EFF15); and 0.5%, 2%, and 4% chlorhexidine for 10 min (0.5% CHX10, 2% CHX10, and 4% CHX10). After the treatments, the specimens were vortexed to release the biofilm and the counting of bacterial colonies was performed (CFU/mL). Three-way ANOVA and the Tukey-Kramer HSD test were used (α = 0.05). For Staphylococcus epidermidis, there was no significant difference between NES30, OPF30, and OPF6 with their respective control groups; nor between NES30, OPF30, and OPF6 themselves, regardless of the biofilm development period (P >0.05). For Staphylococcus aureus, there was no significant difference between NES30 and OPF30 with their control group; nor between NES30 and OPF30 themselves, regardless of the biofilm development period (P >0.05). For Staphylococcus aureus, OPF6 showed a significant reduction in the number of CFU/mL when compared with its control group, NES30, and OPF30, regardless of the biofilm development period (P <0.05). For both bacteria, 0.5% CHX10, 2% CHX10,4% CHX10, and EFF15 showed a significant reduction in the number of CFU/mL when compared with their control groups, NES30, OPF30, and OPF6, regardless of the biofilm development period (P <0.05). Therefore, EFF15 and CHX (0.5%, 2% and 4%) were effective in reducing Staphylococcus epidermidis and Staphylococcus aureus on acrylic surfaces. NES30 and OPF (30 and 6) are not recommended.

Influence of Different Pigmentations and Accelerated Aging on the Hardness and Tear Strength of the A-2186 and MDX4-4210 Silicones.

OBJECTIVE: To evaluate the influence of different pigmentations and accelerated aging on the hardness and tear strength of the A-2186 and MDX4-4210 silicones. MATERIALS AND METHODS: The samples A-2186 and MDX4-4210 were manufactured without and with pigmentations (black, bronze, and pink). For the Shore A hardness test, 80 samples of each silicone were fabricated, and for the tear strength test, 320 samples of each silicone were fabricated. Eight groups were created for each test (n = 10). These tests were performed before and after 252, 504, and 1008 hours of aging. Three-way repeated-measures analysis of variance and the Tukey test were performed (α = 0.05). RESULTS: The A-2186 silicone showed higher hardness and tear strength when compared with the MDX4-4210 silicone (p < 0.05), except in the hardness of the A-2186 and MDX4-4210 groups without pigmentation after 1008 hours (p > 0.05). All hardness values were between 25 and 35 units, regardless of the silicone type, period, and pigmentation (or no pigmentation). In most situations, the hardness of silicones used increased after 252 hours (p < 0.05). The nonpigmented MDX4-4210 group and all A-2186 groups showed an increase in tear strength after 252 hours (p < 0.05). For the nonpigmented MDX4-4210 group, from 252 to 1008 hours, there was no change in tear strength (p > 0.05). All pigmented MDX4-4210 groups showed no change in tear strength from 0 (initial) to 1008 hours of aging (p > 0.05). In all A-2186 groups, from 252 to 504 hours, there was a reduction in tear strength (p < 0.05), and from 504 to 1008 hours, there was an increase in tear strength (p < 0.05), except in the bronze A-2186 group (p > 0.05). CONCLUSION: In most situations, the A-2186 silicone showed significantly higher values of hardness and tear strength than the MDX4-4210 silicone. All hardness values were considered clinically acceptable. Accelerated aging could increase, decrease, or not significantly change the hardness and tear strength of the silicones used. The results of hardness and tear strength suggest that MDX4-4210 was more influenced by the presence of pigmentation after aging.

Prostetic Rehabilitation of an Eye Globe: Case Report.

INTRODUCTION: The lack of an eye has an immediate and long-term impact on a patient's life. AIM: The aim of this study is to show a case of prosthetic rehabilitation of an eyeball. CASE REPORT: Male patient, 60 years old, sought care at the Oral Oncology Center of the São Paulo State University "Júlio de Mesquita Filho", for the rehabilitation of the orbital cavity with an acrylic eye prosthesis. This prosthesis was made with thermopolymerizable acrylic resin and hand painted iris with oil paint on cardboard. The prosthesis was installed after finishing and polishing and the hygiene and general care instructions were explained. CONCLUSION: In the present case, the patient was satisfied with the aesthetics and comfort of the prosthesis, which demonstrates the success of the treatment.