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Clinical Oral Investigations Dec 2022To investigate how different types of dental prosthesis perform in patients with head and neck tumors.
OBJECTIVES
To investigate how different types of dental prosthesis perform in patients with head and neck tumors.
MATERIALS AND METHODS
In this retrospective clinical cohort study, the impact of different patient-related factors was analyzed as influencing factors on the survival probability of dental prosthesis using Kaplan-Meier estimate. For analysis, the dental prosthesis was divided into groups: group 1 (fixed dental prosthesis), group 2 (removable dental prosthesis), group 3 (implant-supported dental prosthesis), and group 4 (prostheses anchored using wrought wire clasps and obturators). The incidental aftercare measures were also evaluated.
RESULTS
Two hundred seventy-nine restorations were observed (mean observation: 2.7 ± 3.0 years, max.14.8 years) out of which 49 (17.6%) had to be replaced during the observation. After 5 years, 100% of group 1 restorations, 79.9% of group 2 restorations, 91.4% of group 3 restorations, and 30% of group 4 restorations were still functional. Four hundred eighty-eight dental implants were observed, of which 77 (15.8%) failed.
CONCLUSIONS
Groups 1, 2, and 3 restorations showed good survival times after 5 years in function, whereas group 4 presented the worst survival times. Group 2 restorations showed the highest amount of necessary aftercare measures.
CLINICAL RELEVANCE
The current investigation shows that groups 1, 2, and 3 restorations should be preferred in the prosthetic treatment planning of patients with head and neck tumors. A treatment with group 4 restorations should only be considered if no other prosthetic treatment is possible or as temporary treatment.
Topics: Humans; Dental Prosthesis, Implant-Supported; Dental Restoration Failure; Dental Implants; Retrospective Studies; Cohort Studies; Head and Neck Neoplasms; Dental Prosthesis Design
PubMed: 35976496
DOI: 10.1007/s00784-022-04673-w -
Journal of Oral and Maxillofacial... Nov 2022Dental occlusion ties (Minne Ties®) are a new example of the concept of an oral zip tie used to establish maxillomandibular fixation (MMF). Each tie uses a blunt...
Dental occlusion ties (Minne Ties®) are a new example of the concept of an oral zip tie used to establish maxillomandibular fixation (MMF). Each tie uses a blunt introducer that is easily passed between embrasures and fed through a self-locking, unidirectional clasp. Five to six ties are used to establish MMF. They are fast, easy to use, and relatively safe because there are no sharps or wires associated with their use. The authors report their experience using this MMF method for temporomandibular joint replacement surgery, where over the last 2 years, over 65 collective cases have been completed using this method.
Topics: Humans; Bone Wires; Dental Occlusion; Jaw Fixation Techniques; Mandibular Fractures; Temporomandibular Joint
PubMed: 35952723
DOI: 10.1016/j.joms.2022.07.003 -
Clinical and Experimental Dental... Dec 2022To investigate the fatigue behavior of cast and laser-sintered cobalt-chromium (CoCr) and polyetheretherketone (PEEK) material for a removable partial denture (RPD)...
OBJECTIVE
To investigate the fatigue behavior of cast and laser-sintered cobalt-chromium (CoCr) and polyetheretherketone (PEEK) material for a removable partial denture (RPD) clasps.
METHODS
Dumbbell-shaped specimens were digitally designed with the center part of the dumbbell being a half-round shape at the cross-sectional dimension of 1.25 mm to simulate a typical clasp design and dimensions. A fatigue machine with an offset axis rotation system simulated a typical undercut depth of 0.25, 0.50, and 0.75 mm. Each group was subjected to 30,000 fatigue cycles (simulating 21 years) or till specimen failure. Before testing, the stress value at each undercut depth for each specimen was established in a universal testing machine and SN curves were plotted for each group. Data were statistically analyzed using Kruskal-Wallis and post hoc tests. The fractured surfaces were analyzed using SEM.
RESULTS
The average fatigue cycles with 0.25, 0.50, and 0.75 mm undercuts were 27,155 ± 6277, 9298 ± 4033, 5642 ± 8785 for cast CoCr and 26,765 ± 6150, 11,318 ± 7931, 2861 ± 4803, for laser-sintered CoCr, respectively. Apart from three specimens, the PEEK groups did not fail during the simulation period. Clasps with 0.25 mm deflection showed significantly higher fatigue resistance than other groups (p < .001). There was no significant difference in fatigue behavior between the cast and laser-sintered CoCr. Microporosities at the fractured site along with irregular crack propagation were observed for cast and laser-sintered CoCr specimens. Fatigue-induced broken polymer crosslinking chains were observed in PEEK specimens.
CONCLUSION
PEEK material exhibited the highest fatigue resistance and significantly lower deflection resistance. Cast and laser-sintered CoCr showed similar fatigue resistance and behavior.
Topics: Denture, Partial, Removable; Cobalt; Chromium; Chromium Alloys; Cross-Sectional Studies; Dental Stress Analysis; Materials Testing; Ketones; Lasers; Polyethylene Glycols
PubMed: 35938907
DOI: 10.1002/cre2.645 -
Current Health Sciences Journal 2022As the number of partially edentulous patients grows, so will the demand for removable partial dentures (RPDs) in clinical practice because it is a safe, conservative,...
As the number of partially edentulous patients grows, so will the demand for removable partial dentures (RPDs) in clinical practice because it is a safe, conservative, and cost-effective alternative that provides good plaque control but necessitates periodic maintenance visits. The goal of this research was to look at the incidence of partial edentulism, RPD type, design, and components, as well as their frequency of use, among patients at the Dental Faculty's Department of Partial Dentures in Iasi.
PubMed: 35911937
DOI: 10.12865/CHSJ.48.01.05 -
The Journal of Advanced Prosthodontics Jun 2022The purpose of the study was to assess the influence of build orientations and density of support structures on the trueness of the 3D printed removable partial denture...
PURPOSE
The purpose of the study was to assess the influence of build orientations and density of support structures on the trueness of the 3D printed removable partial denture (RPD) frameworks.
MATERIALS AND METHODS
A maxillary Kennedy class III and mandibular class I casts were 3D scanned and used to design and produce two 3D virtual models of RPD frameworks. Using digital light processing (DLP) 3D printing, 47 RPD frameworks were fabricated at 3 different build orientations (100, 135 and 150-degree angles) and 2 support structure densities. All frameworks were scanned and 3D compared to the original virtual RPD models by metrology software to check 3D deviations quantitatively and qualitatively. The accuracy data were statistically analyzed using one-way ANOVA for build orientation comparison and independent sample t-test for structure density comparison at (α = .05). Points study analysis targeting RPD components and representative color maps were also studied.
RESULTS
The build orientation of 135-degree angle of the maxillary frameworks showed the lowest deviation at the clasp arms of tooth 26 of the 135-degree angle group. The mandibular frameworks with 150-degree angle build orientation showed the least deviation at the rest on tooth 44 and the arm of the I-bar clasp of tooth 45. No significant difference was seen between different support structure densities.
CONCLUSION
Build orientation had an influence on the accuracy of the frameworks, especially at a 135-degree angle of maxillary design and 150-degree of mandibular design. The difference in the support's density structure revealed no considerable effect on the accuracy.
PubMed: 35855318
DOI: 10.4047/jap.2022.14.3.150 -
The Journal of Contemporary Dental... Mar 2022The aim of this study was to evaluate the displacement of the denture base of conventional acrylic dentures and Click Fit partials in Kennedy's class I and II situations...
AIM/OBJECTIVE
The aim of this study was to evaluate the displacement of the denture base of conventional acrylic dentures and Click Fit partials in Kennedy's class I and II situations in the mandibular arch.
MATERIALS AND METHODS
Four removable partial dentures-two conventional clasp dentures and two attachment dentures (Click Fit)-were designed. The two conventional clasp dentures were retained by C (conventional) clasps, and the two attachment dentures were retained by rigid precision attachments. The displacement of denture bases and the movements of denture bases were investigated, and the influences of denture design were studied.
RESULT
The values obtained were statistically analyzed by using independent -tests. For all statistical purposes, a -value of ≤0.001 was considered significant. The results showed that mean vertical displacements (mm) of the conventional acrylic removable partial denture base for Kennedy's class I mandibular arch under 50, 75, and 100 N forces were 0.0317, 0.04377, and 0.06392, respectively, and those for Kennedy's class II mandibular arch under 50, 75, and 100 N forces were 0.04922, 0.09849, and 0.1522, respectively. Vertical displacements (mm) of the Click Fit removable partial denture base for Kennedy's class I mandibular arch under 50, 75, and 100 N forces were 0.02185, 0.03436, and 0.005365, respectively, and those for Kennedy's class II mandibular arch under 50N, 75N, and 100N forces were 0.0445, 0.07851, and 0.14457, respectively. The difference between the groups was statistically significant ( ≤0.001).
CONCLUSION
The vertical displacement of the denture base retained by conventional C clasps was more than that of the denture base retained by rigid precision attachment. The displacement of the denture base tended to be less when the denture was designed with a rigid connection for the retainer and with cross-arch stabilization as in Kennedy's class I case.
CLINICAL IMPLICATIONS
This research evaluated the vertical denture base displacement using different designs and retention types. Hence, it helped predict the prognosis of different removable partial denture base designs in various clinical conditions.
Topics: Denture Bases; Denture, Partial, Removable; Movement
PubMed: 35781442
DOI: No ID Found -
The Journal of Prosthetic Dentistry Feb 2024Conventional removable partial dentures with metal clasps are still a common option for patients with distal-extension tooth loss. However, unilateral nonmetal clasp... (Randomized Controlled Trial)
Randomized Controlled Trial
Oral health-related quality of life of conventional removable partial dentures, unilateral nonmetal clasp dentures, and shortened dental arch with 2- or 3-tooth unilateral distal extension tooth loss in the mandible: A randomized, crossover, clinical trial.
STATEMENT OF PROBLEM
Conventional removable partial dentures with metal clasps are still a common option for patients with distal-extension tooth loss. However, unilateral nonmetal clasp dentures fabricated by using a thermoplastic denture base resin are increasingly being used. Furthermore, the shortened dental arch concept remains controversial, in spite of being advocated for many years. Nevertheless, these treatment options remain controversial, particularly in patients with the loss of a few distal teeth unilaterally.
PURPOSE
The purpose of this randomized, crossover, clinical trial was to investigate the oral health-related quality of life of participants who requested a new dental prosthesis (unilateral nonmetal clasp dentures or conventional removable partial dentures) at a private practice.
MATERIAL AND METHODS
A 3-period, randomized, crossover design was used in a within-subject, controlled, clinical trial. Twenty-four participants (mean age 59.0 years [7 men: 62.6 {45-85} years; 17 women: 57.5 {24-75} years]) were enrolled. All experimental procedures were approved by the Ethics Committee of Nagasaki University Hospital (#15022313) and registered in the International Standard Randomized Controlled Trial Number registry (ISRCTN49105064). All participants were fully dentate in the maxilla and had unilateral distal-extension loss of 2 or 3 teeth in the mandible. Participants were allocated to 1 of 6 groups and treated with prescribed options in accordance with their allocated sequences and used a dental prosthesis or nothing for 2-week periods. At the end of each intervention, the participants were asked to answer the Oral Health Impact Profile questionnaire. Differences in Oral Health Impact Profile scores among groups were estimated with a mixed-effects model (α=.05).
RESULTS
Total Oral Health Impact Profile scores were higher for unilateral nonmetal clasp dentures (P=.002) and shortened dental arch (P=.049) than for conventional removable partial dentures, with medium and small effects. The unilateral nonmetal clasp dentures had a similar effect compared with shortened dental arch (P>.05). unilateral nonmetal clasp dentures (P=.011) and shortened dental arch (P=.005) demonstrated medium effects in the oral function dimension compared with conventional removable partial dentures. Unilateral nonmetal clasp dentures exhibited large and medium effects in the orofacial appearance dimension compared with conventional removable partial dentures (P=.001) and shortened dental arch (P=.006). In the orofacial pain dimension, shortened dental arch showed effects similar to those of conventional removable partial dentures and unilateral nonmetal clasp dentures (P>.05), and no significant differences were observed in the psychosocial impact dimension (P>.05), but the unilateral nonmetal clasp denture score was lower than the conventional removable partial denture score, with a small effect. Men had significantly lower total Oral Health Impact Profile scores for shortened dental arch than women (P=.033).
CONCLUSIONS
Unilateral nonmetal clasp dentures and shortened dental arch were better than conventional removable partial dentures for the oral health-related quality of life of individuals with unilateral distal-extension tooth loss in the mandible, and sex had a significant effect on removable prosthetic planning.
Topics: Aged; Aged, 80 and over; Female; Humans; Male; Middle Aged; Cross-Over Studies; Dental Arch; Dental Clasps; Denture Design; Denture, Partial, Removable; Mandible; Quality of Life; Tooth Loss; Young Adult; Adult
PubMed: 35697550
DOI: 10.1016/j.prosdent.2021.07.014 -
The International Journal of... May 2023To evaluate the extent to which dentists elaborate removable partial denture (RPD) design themselves and what they leave to the dental laboratory, as well as to assess...
PURPOSE
To evaluate the extent to which dentists elaborate removable partial denture (RPD) design themselves and what they leave to the dental laboratory, as well as to assess the quality of information transferred to the technicians.
MATERIALS AND METHODS
Data were collected using a questionnaire, and the responses of 211 dentists were analyzed. The categorized variables were analyzed using chi-square test and Fisher exact test. The significance level was considered as the standard < .05.
RESULTS
More than half (59.0%) of the dentists reported making an accurate, clear design for the dental technician before fabrication of the metal-framework RPD; 191 dentists (91.0%) specified the abutment teeth, 70.8% chose the type of clasps, and 60.7% gave instructions for the major connectors. The respondents largely took into account periodontal hygiene considerations (82.4%), and about one-third (37.7%) reported they were sending clear, precise instructions to the lab. The denture design was sent to the technician mainly (65.0%) in both drawing and text form. About half of the dentists (55.6%) gave only guidelines and left more details to be defined by the dental technician. Most dentists took responsibility in case of esthetic problems, irrespective of whether the dentist or technician prepared the denture design.
CONCLUSION
Everyday practice concerning RPD design is far from the professional, legal, and ethical guidelines and rules relating to the duties and responsibilities of the dentist in relation to RPD design, and the situation therefore needs to be improved. Int J Prosthodont 2022;36:131-137. doi: 10.11607/ijp.7523.
Topics: Humans; Denture Design; Denture, Partial, Removable; Dentists; Hungary; Dental Technicians; Self-Assessment; Esthetics, Dental; Communication
PubMed: 35649279
DOI: 10.11607/ijp.7523 -
Journal of Prosthodontics : Official... Feb 2023To perform a systematic review that provides an overview of the current literature on fatigue behavior of removable partial denture (RPD) clasp materials based on... (Review)
Review
PURPOSE
To perform a systematic review that provides an overview of the current literature on fatigue behavior of removable partial denture (RPD) clasp materials based on different retentive areas.
MATERIALS AND METHODS
The review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Electronic searches were done via PubMed, Scopus, and OVID for studies reporting on RPD clasps and the fatigue failure of clasp materials. Inclusion criteria were English language with full text and in vitro studies only. Exclusion criteria were studies that did not assess the fatigue of RPD clasp materials. A quality assessment and selection of full-text articles were performed according to Consolidated Standards of Reporting Trials criteria.
RESULTS
A total of 182 articles were initially identified and screened. After applying inclusion and exclusion criteria, 15 articles were selected for the final analysis. Seven of the included studies utilized a vertical insertion/removal testing approach. Ten studies used the constant deflection test. Three studies used untapered specimens, and 12 studies used tapered specimens. Ten studies performed post-test analysis.
CONCLUSIONS
Cobalt-chromium (CoCr) is the strongest material in terms of fatigue in relation to the undercut depth and the modern, digitally manufactured RPD clasp materials also exhibit comparable fatigue behavior. Recent RPD clasp materials such as polyetheretherketone (PEEK) or laser sintered CoCr, however, require further study in terms of their fatigue behavior. In order to improve the quality of future studies, a standardized and calibrated fatigue testing method is needed with standardized specimen size and shape, which will reduce the risk of bias and enable meta-analysis for bulk comparison between studies.
Topics: Chromium Alloys; Dental Clasps; Denture Retention; Denture, Partial, Removable; Materials Testing
PubMed: 35405767
DOI: 10.1111/jopr.13519 -
International Journal of Dentistry 2022The removable partial denture (RPD) components, especially the retentive arm, play a major role in the loading characteristic on supporting structures.
INTRODUCTION
The removable partial denture (RPD) components, especially the retentive arm, play a major role in the loading characteristic on supporting structures.
OBJECTIVE
To evaluate and compare the effect of different clasp designs on the stress distribution pattern, maximum von Mises stress, and average hydrostatic pressure on abutment teeth, as well as edentulous ridges, mini dental implants (MDIs), and peri-implant bone between the conventional removable partial denture (CRPD) and mini dental implant-assisted distal extension removable partial denture (IARPD) using a three-dimensional finite element analysis (3D FEA).
MATERIALS AND METHODS
3D FEA models of mandibular arches, with and without bilateral MDI at the second molar areas, and Kennedy class I RPD frameworks, with RPA, RPI, Akers, and no clasp component, were generated. A total of 200 N vertical load was bilaterally applied on both sides of distal extension areas, and the stress was analyzed by 3D FEA.
RESULTS
The stress concentration of IARPD with RPI clasp design was located more lingually on abutment teeth, MDI, and peri-implant bone, while the other designs were observed distally on the supporting structures. The maximum von Mises stress on the abutment root surface was decreased when the RPDs were assisted with MDIs. The CRPD and IARPD with the Akers clasp design showed the highest von Mises stress followed by the designs with RPA and RPI clasp, respectively. The average hydrostatic pressure in each group was in approximation.
CONCLUSION
The placement of MDIs on distal extension ridges helps to reduce the stress concentration on denture supporting structures. The maximum von Mises stress is affected by the different designs of clasp components. The CRPD and the IARPD with RPI clasp provide the least stress on supporting structures.
PubMed: 35310462
DOI: 10.1155/2022/2416888