Influence of different denture adhesives on patient-based outcomes: A crossover randomized controlled trial.

STATEMENT OF PROBLEM: The influence of different denture adhesive forms on retention, stability, denture movement, and masticatory efficiency have been studied. However, studies that investigated their effect on patient-based outcomes are scarce. PURPOSE: The purpose of this crossover randomized controlled trial was to investigate the influence of 3 different denture adhesive forms on patient satisfaction and oral health-related quality of life (OHRQoL) in edentulous individuals. MATERIAL AND METHODS: A total of 30 edentulous participants were enrolled. They initially received conventional dentures, which they used for 3 months. They were then instructed to use 3 forms of denture adhesives (cushion, paste, and powder) for 3 months each. Patient satisfaction was assessed by using a visual analog scale (VAS), and OHRQoL was assessed by using the oral health impact profile in the edentulous adults instrument. Assessments were done 3 months after wearing the conventional dentures, then after by using each denture adhesive form for 3 months, with a 1-month washout period. The average retention duration for each form and participant preference were also evaluated. Statistical analysis was conducted by using the repeated measures ANOVA test followed by the Scheffé test for VAS scores and retention duration. The Friedman test followed by the Wilcoxon signed-rank test was used for OHRQoL scores (α=.05). RESULTS: Irrespective of their forms, denture adhesives significantly improved patient satisfaction in most aspects (P<.001) and significantly improved OHRQoL (P<.001). VAS scores for the cushion form were significantly higher than those for the other 2 forms regarding general satisfaction, comfort, and ease of cleaning dentures and tissues. For stability and masticatory ability, the cushion and paste forms were significantly better (P<.05) than the powder form. OHRQoL scores were significantly higher (worse) for the powder form compared with the other 2 forms for the functional limitation, physical pain, and physical disability domains, with insignificant differences between the cushion and paste forms (P>.05). The powder form found the shortest retention duration and the least preference. CONCLUSIONS: Denture adhesives significantly improved OHRQoL and almost all aspects of patient satisfaction. The cushion form provided higher satisfaction levels for most aspects, followed by paste and then powder. OHRQoL outcomes were comparable for all forms, except for the functional limitation, physical pain, and physical disability domains, which were significantly better with the cushion and paste forms. The cushion and paste forms were more retentive and more preferred by the participants than the powder form.

Performance of bulk-fill versus conventional nanocomposite resin restorations supporting the occlusal rests of removable partial dentures: An in vitro investigation.

STATEMENT OF PROBLEM: Placing removable partial denture (RPD) rests on composite resin restorations has long been a debatable issue. Despite developments in composite resins such as nanotechnology and bulk-filling techniques, studies investigating the performance of composite resin restorations when used to support occlusal rests remain scarce. PURPOSE: The purpose of this in vitro study was to investigate the performance of bulk-fill versus incremental (conventional) nanocomposite resin restorations when they are used to support RPD rests under functional loading. MATERIAL AND METHODS: Thirty-five caries-free intact maxillary molars of similar coronal size were collected and divided into 5 equal groups (n=7): Enamel (Control) group: rest seats prepared entirely in enamel; Class I Incremental group: Class I cavities restored with incrementally placed nanohybrid resin composite resin (Tetric N-Ceram); Class II Incremental group: Mesio-occlusal (MO) Class II cavities restored with Tetric N-Ceram; Class I Bulk-fill group: Class I cavities restored with high-viscosity bulk-fill hybrid resin composite (Tetric N-Ceram Bulk-Fill); and Class II Bulk-fill group: MO Class II cavities restored with Tetric N-Ceram Bulk-Fill. Occlusal rest seats were prepared mesially in all groups, and clasp assemblies were fabricated and cast in cobalt chromium alloy. Specimens with their clasp assemblies were subjected to thermomechanical cycling using a mechanical cycling machine (250000 masticatory cycles) and 5000 thermal cycles (5 °C to 50 °C). Surface roughness (Ra) was measured with a contact profilometer before and after cycling. Fracture analysis was done using stereomicroscopy, and margin analysis was done with a scanning electron microscope (SEM) before and after cycling. Statistical analysis of Ra was conducted using ANOVA followed by the Scheffé test for between-group comparison and paired t test for within-group comparison. The Fisher exact probability test was used for fracture analysis. The Mann-Whitney test was used for between-group comparison and Wilcoxon signed rank test for within-group comparison for the SEM images (α=.05). RESULTS: Mean Ra increased significantly after cycling in all groups. Significant differences in Ra were found between enamel and all 4 resin groups (P<.001), with no significant differences between incremental and bulk-fill resin groups for both Class I and II specimens (P>.05). No significant differences were found between the 2 resin groups with regard to fracture and margin analysis (P>.05). CONCLUSIONS: The surface roughness of enamel was significantly lower than that of both incremental and bulk-fill nanocomposite resins before and after functional loading. Incremental and bulk-fill nanocomposite resins showed comparable performance in terms of surface roughness, fracture behavior, and marginal adaptation.

Attachment-retained removable prostheses: Patient satisfaction and quality of life assessment.

STATEMENT OF PROBLEM: Studies on the impact of incorporating attachments in removable prostheses on patient-based outcomes are scarce. PURPOSE: The purpose of this clinical study was to investigate oral health-related quality of life (OHRQoL) and patient satisfaction in partially edentulous participants before and after rehabilitation with mandibular attachment-retained removable prostheses as compared with conventional removable prostheses. MATERIAL AND METHODS: This crossover study included 74 participants (aged 36 to 57). Initially, 56 received conventional clasp-retained removable dental prostheses (RDPs), and 18 received conventional overdentures (ODs) based on their mandibular partially edentulous state. Two months later, of the 56 RDP participants, 24 had received extracoronal attachment-retained RDPs, 17 received telescope-retained RDPs, and 15 received bar-attachment retained RDPs. The 18 OD participants received ball attachment-retained ODs. Assessments included Oral Health Impact Profile-short version-14 for OHRQoL and a visual analog scale (VAS) for patient satisfaction. Assessments were done before treatment and 2 months after wearing each prosthesis with a 1-month washout period. Statistical analysis included the Friedman then the Wilcoxon signed rank test for Oral Health Impact Profile-short version-14 scores and repeated measures ANOVA then the Bonferroni or paired t test for VAS scores (α=.05). RESULTS: There were no dropouts. Rehabilitation, irrespective of prosthesis type, significantly improved OHRQoL in all domains and significantly increased overall patient satisfaction (P<.05). When compared with the conventional prostheses, attachment-retained prostheses significantly improved functional limitation, psychological discomfort, and physical limitation domains in all groups (P<.05), as well as the physical pain domain in the OD group (P=.041). General satisfaction, stability, comfort, ability to speak, and ability to masticate significantly increased (P<.05) with attachment-retained prostheses. Conventional prostheses were significantly easier to clean (P<.05) in all groups, except for the telescope-attachment group. CONCLUSIONS: Both conventional and attachment-retained prostheses significantly increased patient satisfaction and improved OHRQoL in all domains as compared with before treatment. However, incorporation of attachments further improved functional limitation, psychological discomfort, and physical limitation domains in all groups, as well as the physical pain domain in the OD group. Participants were more satisfied with their attachment-retained prostheses in most aspects.

Effect on patient satisfaction of mandibular denture tooth arrangement in the neutral zone.

STATEMENT OF PROBLEM: The effect of the neutral zone (NZ) technique on different functional aspects (masticatory performance, speech, and muscle activity) has been studied objectively. Subjectively, some studies reported that their participants felt that NZ dentures were more stable, retentive, and comfortable than conventionally fabricated dentures. These studies, however, lacked a measurable assessment scale or a specifically designed questionnaire. PURPOSE: The purpose of this within-subject, crossover clinical trial was to investigate patient satisfaction levels in edentulous patients after rehabilitation with dentures fabricated using the NZ concept as compared with conventional dentures using a specific, question-oriented patient satisfaction questionnaire. MATERIAL AND METHODS: The clinical trial included 52 participants. Each received one set of conventional dentures and another fabricated based on the NZ concept with a 1-month wash-out period. Participants randomly chose 1 of 2 closed opaque envelopes with 2 denture sequences, either conventional then NZ or NZ then conventional. Hence, participants were blinded to the dentures they wore. Patient satisfaction with each denture type was assessed 6 weeks after insertion by a blinded staff member using a 5-scale questionnaire developed for the most important functional aspects (esthetics, masticatory ability, retention, stability, speech, and comfort). The Wilcoxon Signed Rank test was used to compare the satisfaction scores of the 2 denture types (α=.05). RESULTS: Patient satisfaction scores were significantly higher with the NZ dentures than with the conventional dentures in all aspects; P=.001 for question 2 (opinion of denture appearance) and P<.001 for all other questions. CONCLUSIONS: NZ dentures offer significantly higher levels of patient satisfaction than conventional dentures in all functional aspects (retention, stability, masticatory ability, and speech) as well as in comfort and appearance.

The effect of 2 versus 4 implants on implant stability in mandibular overdentures: A randomized controlled trial.

STATEMENT OF PROBLEM: Dental research is rich with articles that investigated the influence of host-site variables, some implant-related variables (implant length, diameter, taper, design, location, and surface topography), different loading protocols or surgical procedures, and measurement methodology on dental implant stability. However, the number of implants and its effect on implant stability remain unclear. PURPOSE: The purpose of this randomized clinical trial was to investigate the influence of implant number on implant stability by comparing 2 versus 4 implants in mandibular implant overdentures. MATERIAL AND METHODS: The trial included 20 participants with edentulous mandibular ridges. Participants were randomly assigned to 2 equal groups, a 4-implant (experimental) group consisting of 4 implants installed in lateral-canine and premolar regions; and a 2-implant (control) group, consisting of 2 implants in lateral-canine regions. Implant stability was measured using resonance frequency analysis at implant placement and then at 1, 3, 6, 9, and 12 months. The Student t test was used to compare the implant stability quotient (ISQ) values of the anterior implants in the 4-implant and 2-implant groups. One-way ANOVA followed by the post hoc Bonferroni test was used to compare ISQ values among the different follow-up periods within each group (α=.05). RESULTS: Mean ISQ values for anterior implants in the 4-implant group were slightly higher than those recorded for the 2-implant group at all follow-up periods. However, these differences were not statistically significant (P>.05). Within-group comparison revealed an initial decrease in implant stability for all implants. This decrease was statistically significant for the 2-implant group (P<.001) and for posterior implants in the 4-implant group (P<.001). This was then followed by a gradual increase in ISQ values for all implants in both groups. CONCLUSIONS: Increasing the number of implants from 2 to 4 in mandibular implant overdentures did not have a significant influence on implant stability.

Influence of defective complete dentures renewal on TMD; an MRI and clinical controlled prospective study.

BACKGROUND: The influence of complete denture occlusion on temporomandibular disorder (TMD) is controversial. Some studies found that defective occlusion contributes to the development of TMD, while others found no correlation. OBJECTIVE: This prospective controlled study evaluated the relationship between renewal of old defective complete dentures and TMD as evidenced both by clinical examination and magnetic resonance imaging (MRI) findings. MATERIALS AND METHODS: The study included 25 complete denture patients with signs and symptoms of TMD and 21 asymptomatic controls. Clicking was a common finding in all symptomatic joints. All selected participants needed complete denture renewal. MRI and clinical assessment following research diagnostic criteria for TMD guidelines (RDC/TMD) were carried out at baseline and 2 years after new complete denture insertion. Temporomandibular joint (TMJ) pain, muscle pain, clicking and movement limitation were the assessed signs and symptoms. MRIs were conducted to evaluate the TMJs for disc displacement, disc morphology and joint effusion. RESULTS: Complete denture renewal significantly improved the signs and symptoms of TMD in symptomatic group (p < 0.01). Only in the symptomatic group, treatment resulted in a significant increase in joints displaying superior (normal) disc position (symptomatic p < 0.001; asymptomatic p = 0.157). New dentures did not affect disc morphology in both groups (p = 0.5 for both groups) but significantly reduced joint effusion in the symptomatic group (symptomatic p < 0.001; asymptomatic p = 0.5). Relationship between clinical and MRI findings was not one to one. CONCLUSIONS: New complete dentures had a positive impact on TMD signs and symptoms, disc position and joint effusion but not on disc morphology.