Complete Dentures Research Articles

Myths surrounding vertical dimension of occlusion in restorative dentistry: A scoping review.

This scoping review aims to clarify the concept of vertical dimension of occlusion (VDO) in prosthetic dentistry, addressing prevalent myths, and controversies regarding its clinical management and impact on the stomatognathic system. This paper critically examines common beliefs about VDO alteration and its effects on temporomandibular disorders (TMD) through an extensive literature review and an international survey. The survey included 862 general dentists and prosthodontists and explored their approaches to altering VDO and their perceptions of the clinical implications. The literature review provided a thorough analysis of existing research on VDO modification techniques, the adaptability of the stomatognathic system, and the relationship between VDO changes and TMD. The survey revealed insights into dentists' perspectives on VDO, showing that while many practitioners test a new VDO due to concerns about patient adaptation, a significant majority observed that patients typically adjust well to a new VDO regardless of the technique used. The survey highlighted differing beliefs about the need for a gradual process and trial phase for VDO alteration, as well as the stability of modified VDO. Literature review suggests the stability and adaptability of VDO changes due to muscle adaptability and indicates no direct causal or curative link between VDO changes and TMD. Traditional methods for determining VDO in complete dentures may not be suitable for worn dentition, underscoring the need for tailored approaches. This paper suggests that the traditional belief in the need for a prolonged trial phase for VDO alterations may be reconsidered in light of evidence supporting the adaptability of the stomatognathic system. Moreover, it emphasizes the importance of distinguishing between methods suitable for complete dentures and those for managing cases of worn dentition. The purported link between VDO alterations and TMD is also found to lack scientific evidence, highlighting the need for individualized patient care based on current evidence and clinical judgment.

Dentist's role in fabrication of sophisticated complete dentures

Dentist's role in fabrication of sophisticated complete dentures

Evaluation of the effect of thermocycling on the trueness and precision of digitally fabricated complete denture bases

BackgroundWhile many denture base materials are currently available on the market, little data exists regarding their dimensional stability after exposure to the oral environment. This study aimed to evaluate the effect of thermocycling on the trueness and precision of milled, 3-dimensional (3D)-printed, and conventional digitally fabricated complete denture bases (CDBs).MethodsA completely edentulous maxillary stone model was scanned to generate a standard tessellation language (STL) file; this was imported into metal-milling-machine software (Redon Hybrid CAD-CAM metal milling machine, Redon, Turkey) to produce a metal model for fabricating 30 CDBs. These were divided into three groups (n = 10 in each) according to the construction technique: group 1, CAD-CAM milled CDBs; group 2, 3D-printed CDBs; and group 3, conventional compression molded CDBs. All CDBs were scanned after fabrication and evaluated before and after thermocycling using superimposition. The data were analyzed using a one-way ANOVA, Tukey’s post hoc test, and a paired t-test.ResultsThe level of trueness between the CAD-CAM milled, 3D-printed, and compression molded CDBs showed significant differences before and after thermocycling (P < 0.05). Group 1 showed the highest degree of trueness before and after thermocycling, group 3 exhibited a higher degree of trueness than group 2 before thermocycling, and group 2 had a higher degree of trueness than group 3 after thermocycling. There was a significant difference in the precision for each CDB type before and after thermocycling (P < 0.05).ConclusionThe trueness of the CAD-CAM milling system in complete denture (CD) fabrication is superior to that of the 3D printing and conventional compression molding systems before and after thermocycling. Thermocycling had a significant effect on the precision of all CDB types. The compression molding system in CD construction is the most negatively affected via thermocycling with regard to the measures of trueness and precision.Clinical trial numberNot applicable, no human participants were involved.

Prolonged use of old dentures: A qualitative study with Brazilian older adults.

To explore older adults' perceptions, motivations and reasons for using and not replacing old and worn complete dentures over prolonged periods. In-depth, semi-structured interviews were conducted with Brazilian edentulous older adults who were wearing complete dentures which were at least 20 years old. A purposive sampling method was used to recruit participants from an existing waiting list of those referred to a hospital clinic for new dentures. The interviews were video-recorded, transcribed verbatim and analysed using thematic analysis. Sixty-two individuals were assessed and nine were included in the study, aged from 61 to 77 years (mean = 65.4), with seven (77.8%) of them women. The reported time using their current dentures ranged from 22 to 45 years (mean = 28). Content analysis revealed three main themes: the perception of the current dentures' condition after prolonged use; reasons for the prolonged use and non-replacement; and unsuccessful attempts to replace the dentures. Overall, participants acknowledged the poor condition of their dentures and did recognise the need for replacement. Several factors had prompted them to delay or temporarily forego replacement, with financial constraints being the main barrier. Some reported failed attempts to replace the dentures in the past years or months; however, challenging adaptation to the new prostheses led to them reverting back to their old dentures as a fallback solution. Factors influencing prolonged denture use in older adults include a complex interplay of financial aspects, treatment awareness, access and personal factors. Dental professionals can play a pivotal role in promoting timely denture adjustment or replacement by addressing these factors through patient education and personalised care.

Mechanical Assessment of Denture Polymers Processing Technologies.

Removable prostheses have seen a fundamental change recently because of advances in polymer materials, allowing improved durability and performance. Despite these advancements, notable differences still occur amongst various polymer materials and processing technologies, requiring a thorough grasp of their mechanical, physical, and therapeutic implications. The compressive strength of dentures manufactured using various technologies will be investigated. Traditional, injection molding, and additive and subtractive CAD/CAM processing techniques, all utilizing Polymethyl methacrylate (PMMA) as the main material, were used to construct complete dentures. The specimens underwent a compressive mechanical test, which reveals the differences in compressive strength. All the specimens broke under the influence of a certain force, rather than yielding through flow, as is characteristic for plastic materials. For each specimen, the maximum force (N) was recorded, as well as the breaking energy. The mean force required to break the dentures for each processing technology is as follows: 4.54 kN for traditional packing-press technique, 17.92 kN for the injection molding technique, 1.51 kN for the additive CAD/CAM dentures, and 5.9 kN for the subtractive CAD/CAM dentures. The best results were obtained in the case of the thermoplastic injection system and the worst results were recorded in the case of 3D printed samples. Another important aspect depicted is the standard deviation for each group, which reveal a relatively unstable property for the thermoplastic injected dentures. Good results here in terms of absolute property and stability of the property can be conferred to CAD/CAM milled group.

Challenges in Managing an Edentulous Down Syndrome Patient: A Case Report

Patients with Down Syndrome (DS) are caring, affectionate, and quite social. However, the prosthetic management of edentulous patients with DS depends on the level of their disability, developmental delay and neurobehavioral problems. Muscle hypotonia can affect patient gestures and handling of their prostheses. In addition, intraoral manifestations need to be taken into consideration when designing removable complete dentures, such as macroglossia and maxillo-mandibular sagittal and transverse skeletal misalignment. Dentist is asked to be consistent and to establish a gradual and an atraumatic approach based on the cooperation of the patient and his or her parents, and on the importance of follow ups in the integration of removable prostheses to improve the quality of life and the oral health of these individuals. This article presents the prosthetic treatment of an edentulous 29-year-old female patient with DS and a moderate intellectual disability.

Hyoid displacement during swallowing function for completely edentulous subjects rehabilitated with mandibular implant retained overdenture

BackgroundHyoid bone is attached to the mandible, tongue, larynx, temporal bone, and cervical spine via different types of muscles or ligaments. The tongue, mandible, and hyoid system play a crucial role in swallowing function. This within subject study aimed to evaluate the impact of mandibular implant overdentures on the displacement of the hyoid bones during the swallowing process.MethodsTwenty five healthy edentulous subjects were selected for participating in the study. New complete dentures were constructed for all the participants. Subsequently two dental implants were inserted in the canine regions of the participant’s mandibular arch. In order to retain the mandibular prosthesis in place, ball attachments were incorporated into the mandibular dentures to convert them into implant overdentures. Using 10 ml of thin liquid bolus, videofluoroscopy swallowing examination was performed in three different oral conditions: without complete dentures (WCD), with complete denture (CDs), and with a mandibular implant overdenture (IODs). ANOVA with Bonferroni test was used to analyze the data in order to determine how the hyoid displacement varied throughout different oral conditions.ResultsCompared to complete dentures, mandibular implant overdentures showed a significant decrease (P < 0.05) in both anterior hyoid displacement and duration of hyoid maximum anterior excursion (DOHMAE). However, there was a non-significant difference (P > 0.05) between the two oral circumstances in terms of superior hyoid displacement or duration for hyoid maximum elevation (DOHME). There is no penetration or aspiration for both complete denture and implant overdenture oral conditions.ConclusionImplant retained overdentures have a positive effect on hyoid displacement during swallowing of thin liquid bolus consistency relative to conventional complete dentures.Trial registrationRetrospectively registered (NCT06187181) 02/1/2024.

Influence of titanium and titanium-zirconium alloy as implant materials on implant stability of maxillary implant retained overdenture: a randomized clinical trial

BackgroundLong-term success of implant restoration depends on many factors one of them is the sufficient implant stability which is lowered in compromised bone density sites such as the maxilla as it is categorized as type III & IV bone, so searching for a new innovation and updates in implant material and features is very mandatory. So, the aim of this study was to compare between two implant materials (roxolid and traditional titanium) on the primary and secondary stability of implant retained maxillary overdenture.MethodsEighteen completely edentulous patients were selected. All patients received maxillary implant-retained overdentures and lower complete dentures; patients were divided equally into two groups according to the type of implant materials. Group A received a total number of 36 implants made of roxolid material and Group B received a total number of 36 implants made of traditional titanium alloys. Implant stability was assessed using ostell device, the primary implant stability was measured at the day of implant installation however, secondary implant stability was measured after six weeks of implant placement. Paired t-test was used to compare between primary and secondary stability in the same group and an independent t-test was used to compare between the two groups with a significant level < 0.05.ResultsIndependent t-test revealed a significant difference between the two groups with p -value = 0.0141 regarding primary stability and p-value < 0.001 regarding secondary stability, as roxolid implant group was statistically higher stability than titanium group in both. Paired t- test showed a statistically significant difference in roxolid implant group with p-value = 0.0122 however, there was non-statistically significant difference in titanium group with p-value = 0.636. Mann Whitney test showed a significant difference between the two groups regarding amount of change in stability with p value = 0.191. roxolid implant group showed a higher amount of change in stability than the titanium implant group.ConclusionWithin the limitation of this study, it could be concluded that: Roxolid implants showed promising results regarding primary and secondary stability compared to conventional Titanium implants and can be a better alternative in implant retained maxillary overdentures.Trial registrationRetrospectively NCT06334770 at 26–3-2024.

Influence of denture-bearing conditions on masticatory function and patient-reported outcomes measures.

To investigate the influence of different denture-bearing conditions on the masticatory function and patient-reported outcome measures (PROMs) of complete denture wearers. Sixty edentulous patients were selected and allocated into two groups according to the American College of Prosthodontics' (ACP) classification: non-atrophic (NAT) (Classes I and II) (n = 24) and atrophic (AT) (Classes III and IV) (n = 36). All patients received new complete dentures (CDs). The objective variables (masticatory performance and swallowing threshold) were assessed as well as the PROMs (oral health-related quality of life (OHIP-EDENT), patient satisfaction) and quality of the prosthesis, at baseline (using the old CD) and after 4 months new prostheses use. Data were analyzed by Mann-Whitney test followed by the Generalized Equations Estimation (GEE), linear regression and Chi-square test. Higher masticatory performance was observed in the NAT group (p < .05) for both time points, baseline and after 4 months. However, compared to baseline, both groups showed significant masticatory improvement after 4 months (p < .05). Satisfaction and overall quality of life improved after 4 months with no difference between groups (p > .05). Regarding the quality of the CD, baseline results were significantly (p < .05) lower in the AT group, but after 4 months, no significant differences were found between groups and in intragroup analysis (p > .05). The denture-bearing conditions seems to impact masticatory function, but the PROMs are barely affected.

Association between tooth loss-related speech and psychosocial impairment with cognitive function: A pilot study in Hong Kong's older population.

Tooth loss has been associated with cognitive decline, but the underlying mechanisms involving speech and psychosocial impairment remain unclear. To investigate the impact of tooth loss-related speech and psychosocial impairment on cognitive function in Hong Kong's older population. Seventy-six Cantonese-speaking participants between the ages of 51-92 were classified into three groups: patients with complete dentures (CD), partially edentulous patients with less than 10 occluding tooth pairs (OU <10), and at least 10 occluding tooth pairs (OU ≥10). Cognitive function was assessed using the Montreal Cognitive Assessment Hong Kong Version, One-minute Verbal Fluency Task and Hayling Sentence Completion Test. Objective and subjective speech assessments were carried out using artificial intelligence speech recognition algorithm and a self-designed speech questionnaire. The impact of tooth loss on psychosocial condition was evaluated by the Reading the Mind in the Eyes Test and a self-designed questionnaire. Statistical analyses (one-way ANOVA, ANCOVA, Kruskal-Wallis test, Spearman correlation test) were performed. Tooth loss was significantly associated with lower cognitive function (p = .008), speech accuracy (p = .018) and verbal fluency (p = .001). Correlations were found between cognitive function and speech accuracy (p < .0001). No significant difference in tooth loss-related psychosocial impact was found between the three groups. While warranting larger sample sizes, this pilot study highlights the need for further research on the role of speech in the association between tooth loss and cognitive function. The potential cognitive impact of tooth retention, together with its known biological and proprioceptive benefits, supports the preservation of the natural dentition.

A Staged Digital Protocol for the Terminal Dentition for Immediate Loading Using a Provi-guide.

This report describes a step-by-step staged digital protocol for the terminal dentition patient using a Provi-guide. This protocol will improve implant placement accuracy, shorten treatment time, and assure an implant-supported fixed complete denture immediately loaded after extraction of the remaining terminal dentition and complete edentulism. The novelty of the Provi-guide technique described is that it serves 2 objectives: (1) a nonlimiting surgical guide, and (2) a fixed interim prosthesis. Implants placed in the described digital stagged protocol can serve both the interim and the final prosthesis.

Conventionally and digitally fabricated removable complete dentures: manufacturing accuracy, fracture resistance and repairability

ObjectivesConventionally and digitally manufactured removable complete dentures with different dentition forms were examined for manufacturing accuracy (trueness, precision), fracture forces under torsional loading and subsequent repairability. MethodsA total of 90 mandibular prostheses were manufactured. Ten were made using the injection molding technique and finished with prefabricated teeth. 40 bases each, were manufactured subtractively and additively. Digitally the prosthesis’ dental arch was divided either into two quadrants or three sextants, or kept as full arch. Afterwards, ten additive and subtractive bases were finished with prefabricated teeth and ten of each with milled quadrants, sextants and full arches. After manufacturing, all specimens were rescanned for accuracy comparisons using the Root Mean Square (RMS). Lastly, all specimens were tested to failure under torsional loading. ResultsConventionally manufactured dentures showed the greatest deviation in accuracy. The type of base manufacturing did not determine the fracture resistance of the prostheses. The dentition form had a significant influence. While prefabricated teeth (86.01 ± 19.76 N) and quadrants (77.89 ± 9.58 N) showed a low fracture resistance, sextants (139.12 ± 21.41 N) and full arches (141.05 ± 17.14 N) achieved the highest fracture forces. Subtractive bases with prefabricated teeth or quadrants were assessed to be repairable, digital dentures with full arch were assessed as not repairable. SignificanceThe presented testing set-up is suitable to determine the fracture behavior of dentures rather than of standards. With the possibility of digital design and individual manufacturing, dentures’ mechanical stability can be significantly increased, especially with suitable dentition forms.

Revisiting Special Tray Designs for Complete Denture Impression in An Unusual Case of Posterior Palatal Seal Presentation

Revisiting Special Tray Designs for Complete Denture Impression in An Unusual Case of Posterior Palatal Seal Presentation

Complete denture treatment in a resorbed mandibular ridge with suction effective method and neutral zone technique using a semi-adjustable articulator: A case report

Complete denture treatment in a resorbed mandibular ridge with suction effective method and neutral zone technique using a semi-adjustable articulator: A case report

MECHANICAL STRENGTH ANALYSIS OF RESINS PRINTED WITH THE ADDITION OF NB2O5 NANOPARTICLES

Objective: To evaluate the strength of composite resins used for the fabrication of complete dentures after the addition of niobium pentoxide (Nb2O5). Methods: Different concentrations of Nb2O5 were added to the polymer matrix: 0% (control), 0.5%, 1.0%, 1.5%, and 2.0% per 100 mg of resin. In this context, nanoparticles were incorporated under ideal conditions, and the test specimens were designed using Dentsply Sirona’s inLab MC XL software. After the addition of nanoparticles, samples were printed with dimensions of 25 mm in width, 2 mm in height, and 2 mm in thickness. The test specimens were fabricated through digital printing. Finally, the samples were subjected to mechanical testing for flexural strength and impact resistance. Results: The 0.5% and 1.0% groups showed higher flexural strength values (54.56 and 56.8 MPa), with statistical significance (p&lt;0.05) compared to the 1.5% and 2.0% groups (45.26 and 40.65 MPa). Regarding the modulus of elasticity, the 1.0% group presented the highest value (1.15 GPa), while the 0.5% group obtained 0.98 GPa, showing significant statistical differences (p&lt;0.05) between the groups. In terms of impact resistance, the 0.5% and 2.0% groups exhibited the highest resistance, differing significantly from the 1.0% and 1.5% groups (p&lt;0.05). Conclusion: Niobium pentoxide improved the properties of PMMA in this study, proving to be a viable alternative for the development of denture bases.

3D-printed shell complete dentures as a diagnostic aid for implant planning and fabricating interim restorations for complete arch rehabilitations: A case series.

3D-printed shell complete dentures generated from a scan of the patient's existing prostheses can simplify and expedite the surgical planning and interim restoration design for complete arch rehabilitations. Three patients were rehabilitated with endosteal implants, and interim restorations were generated from the contours of the 3D-printed shell complete dentures used as diagnostic aids. This case series report presents the recommended protocol and its clinical progression, in addition to clinical and radiographic images of the treatment outcomes.

Cross-Cultural Adaptation of The Indonesian Version Functional Assessment of Denture Instrument as a Measuring Tool for Complete Denture Functional Quality.

Making good quality dentures is necessary to avoid patients' discomfort when adapting to new dentures. Several studies regarding the assessment of the quality of dentures have been carried out in many other countries, such as using the Functional Assessment of Dentures (FAD) by Anastassiadou. However, studies have yet to be conducted in Indonesia. This study aims to obtain a valid and reliable instrument to measure the quality of complete dentures (CDs). This study also aims to find out whether the functional quality of a CD measured with the Indonesian version of the FAD Instrument (PFGT) can affect patient satisfaction in receiving CD treatment (measured with Indonesian version of Patient's Denture Assessment [PDA-Id]) and to find contributing factors to the functional quality of a CD. The study was conducted in two stages. The first stage was a qualitative study using cross-cultural adaptation methods and focus group discussions with experts. The second stage was a quantitative test with a total of 40 subjects for statistical analysis in the form of a kappa test, test-retest, Kuder-Richardson (KR) 20, and a correlation test between PDA-Id and PFG. Multivariate analysis was done to analyze contributing factors to the functional quality of CD. The final instrument was obtained from the qualitative test, which was tested for content and face validation. The interrater kappa test result of 0.828 shows an almost perfect agreement. The results of the intrarater test-retest (0.564; p > 0.05; intraclass correlation coefficient 0.889) showed excellent instrument stability. The results of the internal consistency test with Kuder-Richardson 20 (1.08; KR > 1) showed good internal consistency. The correlation test results between PFGT and PDA-Id (0.044; p < 0.05) showed a positive correlation. Multivariate analysis showed a relationship between the quality of the CD, the length of time the CD was used, and the patient's satisfaction with CD treatment. The PFGT instrument is considered a valid and reliable tool to measure the functional quality of a denture that can distinguish between good and bad quality.

A functionally graded gyroid-type three-periodic minimal surface framework applied to implant-supported fixed complete dentures

A functionally graded gyroid-type three-periodic minimal surface framework applied to implant-supported fixed complete dentures

Classification system for maxillary fixed dental prostheses.

To present an addendum to existing fixed dental prostheses (FDPs) classification system for maxillary prostheses. The new classification identifies the relationships between FP-1 (fixed prostheses) designs and newly developed clinical interdental gingival contours. Clinical and laboratory descriptions of the various types of full-arch fixed prostheses are described with photographic illustrations. Benefits and limitations of the various prosthetic designs are explained. Surgical differences in the amount of alveolectomy are illustrated. One clinical case is demonstrated. A new classification system for maxillary implant fixed complete dentures is presented. The new system will serve as an improved communication aid for clinicians, patients, and laboratory technicians. Treatment of patients with edentulous maxillae and/or terminal dentitions and implant fixed complete dentures include several options relative to design and materials. Restorative space can have a major impact on prosthesis design and longevity. Early on in dental implant therapy, prostheses were generally made with cast metal frameworks, denture bases and denture teeth. Prosthetic complications were widely reported. With increased clinical experience and improved materials, computer-aided design and computer-aided manufacturing (CAD-CAM) protocols were developed that allowed stronger prostheses to be constructed in reduced or small restorative volumes. FP-1 ceramic implant-supported fixed prostheses (CISFPs) are designed to replace only the dental hard tissues and to promote preservation and rehabilitation of gingival soft tissues. The physical properties and minimum thickness requirements in full arch prostheses are influenced by several factors including distances between implants and rigid connector sizes. FP-1 CISFPs may be the closest prostheses the profession can offer edentulous patients that mimic the look, feel, and function of missing dentitions. Aesthetic outcomes of FP-1 CISFPs are variable and depend on a multitude of factors. This article presented a classification system that builds on existing classification by identifying the level of papilla heights achieved with FP-1 CISFPs.

Impact of occlusal schemes on prognosis of conventional complete dentures in patients with severely resorbed alveolar ridges

Bilateral Balanced Occlusion (BBO) and Canine Guidance (CG) are occlusal schemes that have been successfully used in complete dentures (CDs). The objective of this study was to evaluate the effects of CG compared to BBO on satisfaction, oral health-related quality of life (OHRQoL) and masticatory performance in CDs wearers with severe resorbed alveolar ridge by means of a crossover trial. Sixteen edentulous patients with severe resorbed ridges were treated with new maxillary and mandibular CDs. After adaptation period, they were randomly divided into two groups according to a sequence of occlusal schemes: BBO for 30 days followed by CG for 30 days or, CG for 30 days followed by BBO for 30 days. Patient satisfaction with their dentures, OHRQoL and masticatory performance were assessed immediately 30 days after of using each occlusal scheme. The results of satisfaction and quality of life were using Wilcoxon test, and data regarding masticatory performance were analyzed through paired t-test (α = .05). The occlusal scheme used in complete dentures had no significant influence on general patient satisfaction (p = 0.06), overall quality of life (p = 0.09), or masticatory performance of patients (p = 0.182). Both BBO and CG can be considered as suitable for oral rehabilitation with CDs in patients with severe resorbed alveolar ridges. However, CG may be considered as a scheme of choice by clinicians due to its greater simplicity and shorter execution time.