-
Primary Dental Journal Sep 2020Improvements in oral health including increased retention of natural teeth have given rise to a partially dentate older population. Replacement of missing natural teeth...
Improvements in oral health including increased retention of natural teeth have given rise to a partially dentate older population. Replacement of missing natural teeth is important to improve function, aesthetics and quality of life for this patient group. A variety of options are available to replace missing teeth in partially dentate older adults, including fixed, removable and implant retained prostheses. This article will discuss the provision of removable partial dentures including treatment planning and denture design. When planning removable partial dentures, careful attention must be paid to stabilising the patient prior to delivering any prosthesis. Partial dentures should be designed to minimise the potential for plaque accumulation with carefully designed metal based frameworks. Acrylic resin can also be utilised with attention to detail to minimise the risk of damage to delicate supporting tissues. Removable dentures have the advantage that they can be readily added to in the event of further tooth loss which may be particularly relevant for older adults. Partial dentures which optimise support, retention and stability can function very successfully and significantly improve patients' oral health related quality of life.
Topics: Aged; Denture, Partial; Denture, Partial, Removable; Humans; Mouth, Edentulous; Quality of Life; Tooth Loss
PubMed: 32940586
DOI: 10.1177/2050168420943435 -
Journal of Prosthodontics : Official... Mar 2022To evaluate and compare the benefits and limitations of additive manufacturing for complete denture fabrication. (Review)
Review
PURPOSE
To evaluate and compare the benefits and limitations of additive manufacturing for complete denture fabrication.
METHODS
A PubMed and Google Scholar search for topics pertaining to additive manufacturing for complete dentures was performed. The resulting articles were then divided into topics to allow a narrative review.
DISCUSSION
Determining how printing compares with conventional and milled dentures is critical for the widespread adoption of this fabrication technique. Physical properties, denture tooth bond strength, denture base adaptation and soft-liner bond strength are discussed to establish how printing compares.
CONCLUSIONS
Printing offers many advantages over milled and conventionally processed dentures; however, many questions need to be answered by research. The advantages include reduced cost of most printers compared to milling machines, less material waste, ability to print multiple dentures simultaneously, and complex designs can be fabricated that otherwise could not be milled. Current research has shown flexural strength, fracture toughness, color stability, and denture base adaptation are reduced for printed dentures when compared with milled dentures. Print orientation has been shown to influence accuracy, strength, surface roughness and C. albicans adherence which is not seen with conventional or milled denture materials. These factors do not represent a criticism of printing but rather indicate the need for more research with this new and promising denture fabrication technique. Since printing offers numerous benefits to complete denture fabrication it is likely to have a more significant role in complete denture fabrication in years to come as knowledge increases and materials/techniques continue to advance.
Topics: Computer-Aided Design; Denture Bases; Denture, Complete; Flexural Strength
PubMed: 35313025
DOI: 10.1111/jopr.13426 -
Journal of Prosthodontics : Official... May 2021CAD/CAM complete dentures have increased in popularity and a wide variety of systems are currently available. These prostheses present many advantages for clinicians,... (Review)
Review
PURPOSE
CAD/CAM complete dentures have increased in popularity and a wide variety of systems are currently available. These prostheses present many advantages for clinicians, technicians and patients. Subtractive manufacturing is used by most of the available systems while a few manufacturers use an additive manufacturing technique. This article describes the currently available systems and materials available for the fabrication of CAD/CAM complete dentures and reviews the literature relative to their physical properties.
METHODS
A comprehensive review of the literature was completed to enumerate the currently available techniques to fabricate CAD/CAM complete dentures and discuss their physical properties. A search of English language peer-reviewed literature was undertaken using MEDLINE and PubMed on research articles published between 2000 and 2019. A hand search of relevant dental journals was also completed.
RESULTS
The literature indicates the physical properties of CAD/CAM milled poly(methylmethacrylate) or PMMA as it is commonly described is superior to conventionally processed PMMA for the fabrication of complete dentures.
CONCLUSION
The incorporation of CAD/CAM technology into complete denture design and fabrication streamlines the clinical and laboratory processes and provides improved physical properties that enhance denture quality.
Topics: Computer-Aided Design; Denture Design; Denture, Complete; Humans; Methylmethacrylate
PubMed: 32844510
DOI: 10.1111/jopr.13243 -
The Journal of Prosthetic Dentistry Feb 2021Reports on digital complete dentures (CDs) are increasing. However, systematic reviews on their accuracy and influencing factors are lacking. (Review)
Review
STATEMENT OF PROBLEM
Reports on digital complete dentures (CDs) are increasing. However, systematic reviews on their accuracy and influencing factors are lacking.
PURPOSE
The purpose of this systematic review was to evaluate the accuracy of digital CDs and to summarize influencing factors.
MATERIAL AND METHODS
An electronic search of the English language literature from January 2009 to October 2019 was performed in the database PubMed/MEDLINE, with the results enriched by manual searches and citation mining. Factors investigated in the selected articles included the fabrication technique, type of computer-aided design and computer-aided manufacturing (CAD-CAM) system, shape of reference model, long-term service, analytical method, and statistical indicators.
RESULTS
A total of 522 articles were identified, of which 14 in vitro articles met the inclusion criteria. Eight articles compared the adaptation of the denture base between digital and conventional methods, 4 studies evaluated the occlusal discrepancies, 4 compared the trueness or adaptation of the denture fabricated with CAD-CAM milling and 3D printing, 1 compared the denture adaptation with 4 different CAD-CAM systems, and 2 evaluated the adaptation of the denture base before and after incubation in artificial saliva.
CONCLUSIONS
Most of the studies reported clinically acceptable values for the occlusal trueness and adaptation of digital CDs. The digital CDs showed similar or better adaptation than conventionally fabricated CDs, and the greatest misfit of the intaglio surface was reported in the posterior palatal seal area and border seal area. The fabrication technique, CAD-CAM system, and long-term service were statistically significant in relation to denture accuracy. Clarification is needed concerning the accuracy of digital CDs according to the shape of the cast, the parameters related to the CAD-CAM process, the analytical method, and the statistical indicators. No clear conclusions can be drawn about the superiority of CAD-CAM milling and 3D printing regarding denture accuracy.
Topics: Computer-Aided Design; Denture Design; Denture, Complete; Printing, Three-Dimensional; Research Design
PubMed: 32115218
DOI: 10.1016/j.prosdent.2020.01.004 -
Journal of Prosthodontics : Official... Apr 2021Multiple clinical studies have been published comparing different philosophies of complete denture occlusion and different types of denture teeth. However, it is unclear... (Review)
Review
PURPOSE
Multiple clinical studies have been published comparing different philosophies of complete denture occlusion and different types of denture teeth. However, it is unclear whether comparable data are available for occlusal schemes used with removable partial dentures (RPDs). Therefore, this review investigated the dental literature related to occlusal schemes for RPDs.
MATERIALS AND METHODS
A PubMed search of English language articles was performed using the term "removable partial denture, occlusion" with 765 results. When the term "occlusion in removable partial prosthodontics" was used there were 784 results. Seventy-four articles were identified using the different search term of "RPD, occlusion" while use of the term "occlusal scheme, with removable partial dentures" listed 18 publications. The term "removable partial denture, occlusion, literature reviews" produced 38 potential publications related to the topic. Using the term "removable partial denture occlusion systematic review" resulted in 2 citations. Using the term "RPD occlusion literature review" resulted in one foreign language manuscript whereas using the term "RPD occlusion systematic review" resulted in one article unrelated to dentistry. The term "clinical studies of RPD occlusion" produced 5 results with none related to the topic. There were 23 results using the term "clinical studies of removable partial denture occlusion" with one potentially related to RPD occlusal schemes.
RESULTS
A review of the titles and abstracts revealed 12 articles that appeared to contain specific information about the occlusal scheme used with RPDs. Following a detailed review of those publications, only 4 contained recommendations for RPD occlusion and were included in this review. The available information regarding the recommendations for occlusal schemes in these articles was based on expert opinion. A decision was made to include a hand search of 9 textbooks containing varying amounts of information related to occlusal schemes for RPDs, but no evidence-based references related to RPD occlusal schemes were found in the textbooks. Since this entire review is based on expert opinion, no attempt was made to critique the opinions expressed by these authors but rather to present their perspectives for evaluation by readers.
CONCLUSIONS
The occlusion developed with RPDs should be physiologically harmonious, allowing the supporting structures to remain in a good state of health with functional stress distributed among all the occluding teeth. Multiple authors indicate the occlusion in maximum intercuspation/centric occlusion should incorporate bilateral posterior contacts with no deflective occlusal contacts. When most occlusal contacts on natural teeth are missing, it has been proposed that extension base RPDs have their occlusal contacts developed in centric occlusion. Regarding eccentric occlusal relationships, a balanced occlusal scheme has been recommended by multiple authors with one author advocating use of a lingualized balanced. An anterior guided (canine-protected) occlusion has also been recommended when the canines are present and not periodontally compromised. When RPDs oppose a complete denture, several authors indicate a bilateral balanced occlusion should be used to help stabilize the complete denture.
Topics: Dental Occlusion; Dental Occlusion, Balanced; Denture Design; Denture, Complete; Denture, Partial, Removable
PubMed: 33783088
DOI: 10.1111/jopr.13313 -
Journal of Prosthodontic Research Jan 2022This study comprehensively reviewed the current status of the digital workflow of removable partial dentures (RPDs) and summarized information about the fabrication...
PURPOSE
This study comprehensively reviewed the current status of the digital workflow of removable partial dentures (RPDs) and summarized information about the fabrication methods and material properties of the dental framework, artificial teeth, and denture base.
STUDY SELECTION
We performed a systematic review of the literature published in online databases from January 1980 to April 2020 regarding RPD fabrication and materials used in the related digital technology. We selected eligible articles, retrieved information regarding digital RPDs, and conducted qualitative/quantitative analyses. In this paper, the computer-aided design/computer-aided manufacturing (CAD/CAM) framework, artificial teeth, and denture base materials are reported.
RESULTS
A variety of materials, such as cobalt-chromium alloy, titanium, zirconia, and polyether ether ketone, are used for dental CAD/CAM frameworks. The mechanical strength of the metal materials used for the CAD/CAM framework was superior to that of the cast framework. However, the fitness and surface roughness of the framework and clasp fabricated using a selective laser melting (SLM) method were not superior to those obtained via cast fabrication. Most material properties and the surface roughness of poly methyl methacrylate (PMMA) discs used for digital RPDs were superior to those of heat-cured PMMA.
CONCLUSION
The use of a CAD/CAM framework and PMMA disc for digital RPDs offers numerous advantages over conventional RPDs. However, technical challenges regarding the accuracy and durability of adhesion between the framework and denture base remain to be solved. In digital fabrication, human technical factors influence the quality of the framework.
Topics: Computer-Aided Design; Denture Bases; Denture, Partial, Removable; Humans; Tooth, Artificial; Workflow
PubMed: 33504722
DOI: 10.2186/jpr.JPR_D_20_00117 -
Journal of Prosthodontics : Official... Apr 2021The occlusal scheme required for an edentulous patient is controversial. The purpose of this Best Evidence Consensus Statement was to evaluate the existing complete... (Review)
Review
PURPOSE
The occlusal scheme required for an edentulous patient is controversial. The purpose of this Best Evidence Consensus Statement was to evaluate the existing complete denture literature related to occlusal schemes.
MATERIALS AND METHODS
A literature search was limited to Meta-analyses, Systematic Reviews (SR), Randomized Controlled Studies (RCT) and Clinical Trials. Key Words were: Complete dentures, occlusion, harm; Complete dentures, occlusion alveolar bone loss; Complete dentures, occlusion, stability; Complete dentures, occlusion. Additional related articles were culled from the authors' library and reference lists in the articles found in the PubMed searches.
RESULTS
Of the 165 articles that met the initial search criteria, 34 related to the focus questions and were evaluated and rated.
CONCLUSIONS
There is strong support that the average denture patient, with good residual ridges and no neuromuscular problems, will function adequately with a properly fabricated complete denture regardless of the occlusal scheme. There is neither strong support for or against bilateral balanced occlusal schemes as it relates to patient satisfaction, preference or chewing ability. There is some support for increased alveolar bone loss with complete dentures that have a non-balanced occlusion. There is a need for bilateral balanced occlusal schemes for patients presenting with loss of stability and retention as a result of their presenting conditions (PDI III and IV).
Topics: Consensus; Dental Occlusion; Dental Occlusion, Balanced; Denture Design; Denture, Complete; Humans; Mastication
PubMed: 33336857
DOI: 10.1111/jopr.13309 -
The Cochrane Database of Systematic... Apr 2018Edentulism is relatively common and is often treated with the provision of complete or partial removable dentures. Clinicians make final impressions of complete dentures... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Edentulism is relatively common and is often treated with the provision of complete or partial removable dentures. Clinicians make final impressions of complete dentures (CD) and removable partial dentures (RPD) using different techniques and materials. Applying the correct impression technique and material, based on an individual's oral condition, improves the quality of the prosthesis, which may improve quality of life.
OBJECTIVES
To assess the effects of different final-impression techniques and materials used to make complete dentures, for retention, stability, comfort, and quality of life in completely edentulous people.To assess the effects of different final-impression techniques and materials used to make removable partial dentures, for stability, comfort, overextension, and quality of life in partially edentulous people.
SEARCH METHODS
Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 22 November 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Register of Studies, to 22 November 2017), MEDLINE Ovid (1946 to 22 November 2017), and Embase Ovid (21 December 2015 to 22 November 2017). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on language or publication status when searching the electronic databases, however the search of Embase was restricted by date due to the Cochrane Centralised Search Project to identify all clinical trials and add them to CENTRAL.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) comparing different final-impression techniques and materials for treating people with complete dentures (CD) and removable partial dentures (RPD). For CD, we included trials that compared different materials or different techniques or both. In RPD for tooth-supported conditions, we included trials comparing the same material and different techniques, or different materials and the same technique. In tooth- and tissue-supported RPD, we included trials comparing the same material and different dual-impression techniques, and different materials with different dual-impression techniques.
DATA COLLECTION AND ANALYSIS
Two review authors independently, and in duplicate, screened studies for eligibility, extracted data, and assessed the risk of bias for each included trial. We expressed results as risk ratios (RR) for dichotomous outcomes, and as mean differences (MD) or standardised mean differences (SMD) for continuous outcomes, with 95% confidence intervals (CI), using the random-effects model. We constructed 'Summary of findings' tables for the main comparisons and outcomes (participant-reported oral health-related quality of life, quality of the denture, and denture border adjustments).
MAIN RESULTS
We included nine studies in this review. Eight studies involved 485 participants with CD. We assessed six of the studies to be at high risk of bias, and two to be at low risk of bias. We judged one study on RPD with 72 randomised participants to be at high risk of bias.Overall, the quality of the evidence for each comparison and outcome was either low or very low, therefore, results should be interpreted with caution, as future research is likely to change the findings.Complete denturesTwo studies compared the same material and different techniques (one study contributed data to a secondary outcome only); two studies compared the same technique and different materials; and four studies compared different materials and techniques.One study (10 participants) evaluated two stage-two step, Biofunctional Prosthetic system (BPS) using additional silicone elastomer compared to conventional methods, and found no evidence of a clear difference for oral health-related quality of life, or quality of the dentures (denture satisfaction). The study reported that BPS required fewer adjustments. We assessed the quality of the evidence as very low.One study (27 participants) compared selective pressure final-impression technique using wax versus polysulfide elastomeric (rubber) material. The study did not measure quality of life or dentures, and found no evidence of a clear difference between interventions in the need for adjustments (RR 0.81, 95% CI 0.38 to 1.70). We assessed the quality of the evidence as very low.One study compared two stage-two step final impression with alginate versus silicone elastomer. Oral health-related quality of life measured by the OHIP-EDENT seemed to be better with silicone (MD 7.20, 95% CI 2.71 to 11.69; 144 participants). The study found no clear differences in participant-reported quality of the denture (comfort) after a two-week 'confirmation' period, but reported that silicone was better for stability and chewing efficiency. We assessed the quality of the evidence as low.Three studies compared single-stage impressions with alginate versus two stage-two step with elastomer (silicone, polysulfide, or polyether) impressions. There was no evidence of a clear difference in the OHIP-EDENT at one month (MD 0.05, 95% CI -2.37 to 2.47; two studies, 98 participants). There was no evidence of a clear difference in participant-rated general satisfaction with dentures at six months (MD 0.00, 95% CI -8.23 to 8.23; one study, 105 participants). We assessed the quality of the evidence as very low.One study compared single-stage alginate versus two stage-two step using zinc-oxide eugenol, and found no evidence of a clear difference in OHIP-EDENT (MD 0.50, 95% CI -2.67 to 3.67; 39 participants), or general satisfaction (RR 3.15, 95% CI 0.14 to 72.88; 39 participants) at six months. We assessed the quality of the evidence as very low.Removable partial denturesOne study randomised 72 participants and compared altered-cast technique versus one-piece cast technique. The study did not measure quality of life, but reported that most participants were satisfied with the dentures and there was no evidence of any clear difference between groups for general satisfaction at one-year follow-up (low-quality evidence). There was no evidence of a clear difference in number of intaglio adjustments at one year (RR 1.43, 95% CI 0.61 to 3.34) (very low-quality evidence).
AUTHORS' CONCLUSIONS
We conclude that there is no clear evidence that one technique or material has a substantial advantage over another for making complete dentures and removable partial dentures. Available evidence for the relative benefits of different denture fabrication techniques and final-impression materials is limited and is of low or very low quality. More high-quality RCTs are required.
Topics: Dental Impression Materials; Dental Impression Technique; Denture Design; Denture Retention; Denture, Partial, Removable; Dentures; Humans; Mouth, Edentulous; Quality of Life; Randomized Controlled Trials as Topic
PubMed: 29617037
DOI: 10.1002/14651858.CD012256.pub2 -
Journal of Oral Rehabilitation Nov 2017Determination of the occlusal vertical dimension (OVD) is an integral part of complete dentures fabrication. Due to the lack of teeth, the clinician faces the challenge... (Review)
Review
Determination of the occlusal vertical dimension (OVD) is an integral part of complete dentures fabrication. Due to the lack of teeth, the clinician faces the challenge of how to accurately establish the OVD of the new denture. Therefore, the purpose of this review article was to present, discuss and critique the available methods used in determining the OVD for complete dentures patients. This review identified two main streams to determine the OVD: (i) pre-extraction methods and (ii) post-extraction methods. For the pre-extraction methods, the OVD of the natural dentition is transferred to the new dentures mainly by intra-oral measurements, profile tracing and cephalometric analysis. The post-extraction methods rely on mandibular rest position, facial aesthetic appearance, swallowing pattern, craniofacial landmarks measurements, cephalometric analysis, phonetics and existing dentures. In general, all the available techniques have merits and are helpful for routine clinical use. However, they are empirical in nature, controversial and lack the scientific support. Further, there is no single accurate method for OVD determination. To overcome the limitations of the techniques, the clinician will benefit from applying combination of techniques to approximate the OVD.
Topics: Centric Relation; Cephalometry; Denture Design; Denture, Complete; Humans; Mouth, Edentulous; Surface Properties; Vertical Dimension
PubMed: 28600914
DOI: 10.1111/joor.12522 -
The Journal of Prosthetic Dentistry Apr 2019Complete dentures fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM) techniques have become popular. The 2 principal CAD-CAM techniques,...
STATEMENT OF PROBLEM
Complete dentures fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM) techniques have become popular. The 2 principal CAD-CAM techniques, milling and rapid prototyping (3D printing), used in the fabrication of complete dentures have been reported to yield clinically acceptable results. However, clinical trials or in vitro studies that evaluated the accuracy of the 2 manufacturing techniques are lacking.
PURPOSE
The purpose of this in vitro study was to compare the differences in trueness between the CAD-CAM milled and 3D-printed complete dentures.
MATERIAL AND METHODS
Two groups of identical maxillary complete dentures were fabricated. A 3D-printed denture group (3DPD) (n=10) and a milled denture group (MDG) (n=10) from a reference maxillary edentulous model. The intaglio surfaces of the fabricated complete dentures were scanned at baseline using a laboratory scanner. The complete dentures were then immersed in an artificial saliva solution for a period of 21 days, followed by a second scan (after immersion in saliva). A third scan (after the wet-dry cycle) was then made after 21 days, during which the complete dentures were maintained in the artificial saliva solution during the day and stored dry at night. A purpose-built 3D comparison software program was used to analyze the differences in the trueness of the complete dentures. The analyses were performed for the entire intaglio surface and specific regions of interest: posterior crest, palatal vault, posterior palatal seal area, tuberosity, anterior ridge, vestibular flange, and mid-palatal raphae. Independent t tests, ANOVA, and post hoc tests were used for statistical analyses (α=.05).
RESULTS
The trueness of the milled prostheses was significantly better than that of the rapid prototyping group with regard to the entire intaglio surface (P<.001), posterior crest (P<.001), palatal vault (P<.001), posterior palatal seal area (P<.001), tuberosity (P<.001), anterior ridge (baseline: P<.001; after immersion in saliva: P=.001; after the wet-dry cycle: P=.011), vestibular flange (P<.001), and mid-palatal raphae (P<.001).
CONCLUSIONS
The CAD-CAM, milled complete dentures, under the present manufacturing standards, were superior to the rapidly prototyped complete dentures in terms of trueness of the intaglio surfaces. However, further research is needed on the biomechanical, clinical, and patient-centered outcome measures to determine the true superiority of one technique over the other with regard to fabricating complete dentures by CAD-CAM techniques.
Topics: Computer-Aided Design; Denture Design; Denture, Complete; Humans; Maxilla; Printing, Three-Dimensional
PubMed: 30711292
DOI: 10.1016/j.prosdent.2018.09.001