Mandibular overdentures retained by 1 or 2 implants: a 5-year randomized clinical trial on implant stability and peri-implant outcomes.

AIM: This is a report of the 5-year results of a two-group parallel randomized clinical trial comparing longitudinal implant stability, and clinical and radiographic peri-implant outcomes of mandibular overdentures retained by one (1-IOD group) or two (2-IOD group) implants. METHODS: All participants received 4.1 mm diameter tissue-level implants (Straumann® Standard Plus - SLActive®, Institut Straumann AG), installed in the mandible midline (1-IOD; n = 23) or the lateral incisor-canine area bilaterally (2-IOD; n = 24), and loaded after 3 weeks. Implant Stability Quotient (ISQ) was measured using a resonance frequency device (Osstell® Mentor, Integration Diagnostics) at implant placement, after three weeks (loading), and at the 6-month, 1-, 3-, and 5-year follow-ups. Marginal bone loss and clinical implant outcomes (plaque, calculus, suppuration and bleeding) were assessed periodically up to 5 years after loading. RESULTS: Only minor changes in marginal bone level were observed after 5 years (mean = 0.37; SD = 0.44 mm), and satisfactory and stable peri-implant parameters were observed throughout the 5-year follow-up. No significant differences between groups were found. Overall, the mean primary implant stability was considered high (> 70) for the two groups (1-IOD = 78.1 ± 4.5; 2-IOD = 78.0 ± 5.8). No noticeable changes were observed between implant insertion and loading. A marked increase was observed from insertion to the 6-month follow-up - the mean difference for the 1-IOD group was + 5.5 ± 5.5 (Effect size = 1.00), while for the 2-IOD group, the mean difference was + 6.0 ± 5.6 (Effect size = 1.08). No relevant changes were observed throughout the follow-up periods up to 5 years. Linear mixed-effect model regression showed no influence of the bone-related variables (p > 0.05) and the number of implants (p = 0.087), and a significant effect of the time variable (p < 0.001). CONCLUSION: Satisfactory peri-implant outcomes and stable secondary stability suggest good clinical performance and successful long-term osseointegration of the implants for single and two-implant mandibular overdentures. Using a single implant to retain a mandibular overdenture does not seem to result in detrimental implant loading over the five years of overdenture use. CLINICAL RELEVANCE: This study corroborates the use of a single implant to retain a mandibular denture.

Mandibular overdenture retained by four one-piece titanium-zirconium mini implants: A 2-year RCT on patient-reported outcomes.

AIM: The positive impact of implant interventions on dental patient-reported outcomes is an essential parameter of treatment effectiveness. This study assessed the 2-year changes in patient satisfaction and oral health-related quality of life (OHRQoL) of edentulous patients treated with a four mini implant mandibular overdenture (IOD) METHODS: The study was planned as a 2 × 2 factorial randomized clinical trial that tested two surgical approaches (flapped or flapless) and two loading protocols (immediate and delayed) using a titanium-zirconium mini implant (Straumann Mini Implant System®) and a PEEK retentive system (Straumann® Optiloc® Retentive System). Outcome measures (OHIP-Edent scores and the McGill Denture Satisfaction questionnaire) were assessed before treatment and at the 3-, 6-, 12-, and 24-month follow-ups. The Friedman test and multiple regression using Generalized Estimating Equations (GEE) were used for data analysis, considering the per-protocol (PP) and intention-to-treat (ITT) approaches RESULTS: Seventy-four patients were randomized to the study groups. No implant failure occurred during the study period. Marked improvement in all post-treatment periods compared to baseline were observed for the two outcomes. No significant effect of patient's gender, age, and surgical protocol on the study outcomes. The effect of treatment provision was significant for the two outcomes in the PP and ITT approaches (p < 0.001). A barely significant positive effect of the immediate loading was observed for OHIP-Edent in the PP approach (p = 0.020) CONCLUSION: IOD treatment significantly improved patient-reported outcomes measures, with sustained benefits over the two years of overdenture use, and can be considered a promising treatment option in for the edentulous mandible.

Mandibular overdenture retained by four one-piece titanium-zirconium mini implants: A 2-year follow-up on prosthodontic outcomes.

OBJECTIVE: This 2-year prospective study reports the incidence of prosthetic complications and maintenance events after treatment with mandibular overdenture retained by four mini implants opposed to a maxillary denture. METHODS: Implant intervention included flapless or flapped surgery combined with immediate or delayed loading, as part of a randomized clinical trial. Four one-piece titanium-zirconium mini-implants (Straumann Mini Implant System) were inserted, and the retentive PEEK elements (Optiloc) were incorporated into the overdenture using chairside procedures. Prosthodontic complications and maintenance events were recorded over a 2-year follow-up, and the final outcome was defined according to standardized criteria. Data analysis included descriptive statistics, incidence and incidence density rates, and Kaplan-Meier survival. RESULTS: 73 out of 74 patients (64.9 % female), mean age of 64 (SD=8.2) years, completed the study follow-up (one withdrew after 9 months). Implant survival was 100 %. A total of 163 prosthodontic events occurred in 53 patients (72.6 %), and 20 patients had no clinical complaints or maintenance needs. The most common procedures were adjustment/repair of the overdenture base (47.0 %), replacement of retentive inserts (19.8 %), and laboratory relining (12.9 %). A high prosthodontic success rate was achieved (93.2 %), and all patients presented serviceable overdentures and continuous use after the resolution of prosthodontic complications. The incidences of matrix replacement and laboratory relines were low in the first year, while denture base adjustments were common within the first year, especially in the first 6 months. CONCLUSION: The mini implant system showed high prosthodontic success rates. Minor adjustments/repairs during the initial follow-up were common. Relines and matrix replacements tend to occur after one year of overdenture use, and matrix replacements may occur as a consequence of the need for relining.

Four-year assessment of masticatory function in mandibular overdenture wearers: A randomised clinical trial comparing two to four implants to retain the prosthesis.

BACKGROUND: Limited data exist on the mid- to long-term masticatory capacity of mandibular overdenture (IOD) wearers, particularly regarding the use of posterior implants to retention. OBJECTIVES: To periodically evaluate mastication of IOD wearers, comparing the effectiveness of two to four implants to retain the prosthesis. METHODS: In a randomised controlled clinical trial, 20 complete edentulous patients (14 women), aged 51-84 years (mean age 69.1 ± 9.6), received new bimaxillary complete dentures (CD). After adaptation, baseline measurements of masticatory performance (X50) and swallowing threshold were conducted using the sieving method. Patients were then randomly assigned to groups: control (two intra-foraminal regular implants) and experimental (two intra-foraminal regular implants and two extra-short posterior implants) (n = 10 each). After 4 months, implants were splinted, and a new mandibular IOD was fabricated with bar/clip retention. Mastication was reassessed after 6, 12, and 48 months, and data analysed with repeated measures ANOVA and Sidak's post hoc (α = 0.05). RESULTS: Despite a loss of two patients per group, masticatory performance significantly improved after mandibular IOD installation (p = .031) in both groups (p = .670). A second improvement was observed after 6 months (p = .027), with no subsequent changes (p > .05). Swallowing threshold improvements were noted with IOD, and no discernible differences between groups were observed (p > .05). CONCLUSION: Masticatory function significantly improved after mandibular IOD installation, with the number of implants demonstrating minimal influence. CLINICAL TRIAL REGISTRATION: The present study was not registered in a public database, as mandated. It is important to note that the recommendation for registration was initiated in 2017 by the Committee of Medical Journal Editors, while patient inclusion in the research took place in 2016. Given that the data presented in this manuscript cover a follow-up period of up to 4 years post-surgical intervention, delayed registration was not feasible.

Retention of Mandibular Complete Overdentures using Mini Dental Implants (Ø < 3 mm) and Standard Diameter Implants (Ø > 3mm): A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

PURPOSE: The objective of the present systematic review and meta-analysis was to assess randomised controlled trials (RCTs) which assessed the efficacy of mini dental implants (MDIs) and standard-diameter implants (SDIs) in retaining mandibular overdentures (MO). MATERIALS AND METHODS: The focused question was "Is there a difference in the mechanical stability between MDIs and SDIs in retaining MO?" Indexed databases were searched up to and including November 2023 using different keywords. Boolean operators were used during the search. The literature was searched in accordance with the PRISMA guidelines. The PICO characteristics were: patients (P) = individuals with complete mandibular dentures requiring dental implants; Intervention (I) = placement of MDIs under mandibular dentures; Control (C) = placement of SDIs under mandibular dentures; Outcome (O) = comparison of stability between MDIs and SDIs in supporting mandibular dentures. Only RCTs were included. Risk of bias (RoB) was assessed using the Cochrane RoB tool. RESULTS: Five RCTs were included. The numbers of participants ranged between 45 and 120 edentulous individuals wearing complete mandibular dentures. The mean age of patients ranged between 59.5 ± 8.5 and 68.3 ± 8.5 years. The number of MDIs and SDIs ranged between 22 and 152 and 10 and 80 implants, respectively. The follow-up duration ranged between one week and 12 months. Three RCTs reported an improvement in the quality of life (QoL) of all patients after stabilisation of mandibular dentures using MDIs or SDIs. In one RCT, peri-implant soft tissue profiles were comparable between MDIs and SDIs at the 1-year follow-up. The implant survival rate was reported in two RCTs, which were from 89% to 98% and 99% to 100% for MDIs and SDIs, respectively. All RCTs had a low RoB. CONCLUSION: Mini dental implants represent a viable alternative to traditional standard-diameter implants when seeking optimal retention for mandibular overdentures.

Clinical and radiographic outcomes around 4 mandibular implant-retained overdentures in individuals with type 2 diabetes: A long-term retrospective study.

OBJECTIVES: To report the implant survival rates, clinical, and radiographic status after a period of more than 5 years in the function of 4 inter-foraminal implants retaining mandibular overdentures (OVDs) in individuals with T2DM. METHODS: 78 completely edentulous participants with type 2 diabetic mellitus (T2DM) who had worn mandibular OVDs retained by 4 inter-foraminal implants for long-term functional life were selected for this study. The participants were divided into 2 groups according to glycosylated haemoglobin A1c (HbA1c) levels before implant placement: group I with an HbA1c value > 6.5 % (inadequately controlled T2DM), and group II with an HbA1c value ≤6.5 % (well-controlled T2DM). The inadequately controlled T2DM was further subdivided into 2 groups: Group IA with an HbA1c value > 6.5 % and ≤8 % (moderately controlled), and Group IB has an HbA1c value > 8 % (poorly controlled). Implant survival rate, plaque index (PI), bleeding on probing (BOP), probing depth (PD), and radiographic crestal bone level (CBL) around implants were measured. RESULTS: Among 312 implants, 6 failed, 4 in well-controlled diabetics, and 2 in inadequately controlled diabetics. The overall survival rate was 98.07 %. The mean PI in group Ι was 36.4 (group IA =37.76, group IB = 34.27), and in group ΙΙ it was 19. The mean BOP in group Ι was 45.5 (group IA =47.84, group IB = 41.76), and in group ΙΙ it was 22. The mean PD in group Ι was 4.1 (group IA =4.3, group IB = 3.85) and in group ΙΙ was 2.2. The mean radiographic CBL in group Ι was 3.4 (group IA =3.7, group IB = 2.9), and in group ΙΙ was 1.5. Group IA exhibited a significantly greater level of PI, BOP, PD, and CBL compared to group IB and group IΙ (P1=0.017, P2=0.001). CONCLUSIONS: Individuals with T2DM can benefit from 4 inter-foraminal implants retained mandibular OVDs, and their inability to maintain proper glucose control may not exclude implant success. CLINICAL SIGNIFICANCE: This study is a significant step toward improving knowledge of options available for treatment and anticipated outcomes for T2DM completely edentulous populations undergoing implant therapy.

One-time definitive attachment connection versus healing abutment placement for an implant-retained mandibular overdenture: Peri-implant metabolic activity.

STATEMENT OF PROBLEM: Unscrewing the healing abutment can affect the soft tissue integration and apical migration of the biological width, which may compromise the integrity of peri-implant soft tissue. PURPOSE: The purpose of this clinical study was to determine the level of glycosaminoglycan (GAG) detected in the peri-implant crevicular fluid (PICF) between the test group (1-time abutment) and control group (healing abutment) for implant-retained mandibular overdentures. MATERIAL AND METHODS: Two dental implants were installed in the canine regions of the mandibular ridge of 18 healthy completely edentulous participants using 2-stage surgery and a delayed loading protocol. At the second stage surgery, the implant on the right side was exposed, and a healing abutment was screwed onto the implant (control group), while on the left side the definitive ball abutment was screwed onto the implant (test group). After 10 days, the healing abutment in the control group was unscrewed and replaced with the definitive ball abutment. For both groups, the ball attachment was directly picked up to incorporate the attachment house to the mandibular denture. PICF samples were collected from the participants at 7 days, 3 months, and 6 months after overdenture use. Statistical analysis was done with an independent samples t test (α=.05). RESULTS: A significant difference was found in the volume of PICF and the level of GAG between the test and control groups at the 7-day evaluation period (P=.008, P=.002, respectively), while the volumes of PICF and the levels of GAG were not significantly different (P>.05) at the other evaluation periods. CONCLUSIONS: The 1-time abutment protocol offers biochemical and economic advantages compared with the conventional method of using the healing abutment before placement of the definitive attachment for an implant-retained overdenture with single attachments.

Changes in masticatory performance and bite force after treatment with mandibular overdentures retained by four titanium-zirconium mini implants: One-year randomised clinical trial.

OBJECTIVE: This prospective study is part of a randomised clinical trial and reports the changes in masticatory performance (MP) and bite force, and explores their influential factors, 1 year after the provision of mandibular overdentures retained by four titanium-zirconium mini implants. METHODS: Edentulous patients received conventional complete dentures, followed by placement of four mini implants (Straumann® Mini Implant System) in the anterior mandible and converting the conventional prosthesis into a mandibular overdenture. Treatment protocols were randomised using a 2×2 factorial design combining different surgical (flapped vs. flapless) and loading (immediate vs. delayed) protocols. MP was assessed using a two-colour mixing ability test and a colorimetric analysis to measure the level of colour mixing (Variance of Hue-VoH). Maximum voluntary bite force (MBF) was measured by a digital gnathodynamometer in the posterior and anterior regions. Sex, age, surgical and loading protocols and ridge morphology were tested as independent variables. MP and MBF tests were performed at baseline (pre-treatment) and the 3-, 6- and 12-month after implant loading. Descriptive statistics, independent t-test, and linear mixed-effect model (LMM) regression were used for data analysis. RESULTS: Seventy-four participants were assessed and 73 completed the 1-year follow-up. Statistically significant improvements in functional parameters were observed in all follow-up periods compared to baseline (p < .001). The flapless protocol was associated with higher improvement in MP at the 3-month follow-up (p = .004), while less resorbed ridges were associated with better MP (p = .038) and higher MBF (p < .001). CONCLUSION: The mandibular overdenture protocol using four titanium-zirconium mini implants was effective in improving MP and MBF of edentulous patients, compared to pre-treatment values. The findings also suggest that improvements in chewing function and bite force are impacted by clinical factors since better outcomes were observed for flapless surgeries and less resorbed edentulous ridges. CLINICAL TRIAL REGISTRATION: ClinicalTrials.Gov ID NCT04760457.

A 1-Year Parallel-Group Randomized Clinical Trial Comparing the Effectiveness of a Mandibular Complete Denture vs an Early Loaded Single-Implant Overdenture.

PURPOSE: To assess the effectiveness of converting a conventional mandibular denture (CMD) into a single-implant mandibular overdenture (SIMO). MATERIALS AND METHODS: Edentulous patients received a new CMD and were randomly assigned to the CMD or SIMO group. For SIMO patients, a midline early-loaded implant was inserted and incorporated into the CMD after 3 weeks. Patient satisfaction and oral health-related quality of life were assessed at baseline and up to 1 year. Regression models were constructed using Generalized Estimating Equation (GEE). RESULTS: After 12 months, 32 patients were assessed (CMD: n = 17; SIMO: n = 15). Significant improvement was observed for the SIMO group compared to baseline measures. CONCLUSIONS: SIMO may be considered an effective alternative for patients unsatisfied with their CMDs.

Displasia ectodérmica: relato de caso de reabilitação estético-funcional / Ectodermal dysplasia: a case report of aesthetic-functional rehabilitation

Objetivo: Descrever o caso clínico de um paciente portador de displasia ectodérmica (DE), discutindo as principais características desta síndrome e o tratamento odontológico proposto. Relato do caso: Paciente do sexo masculino com 6 anos de idade procurou atendimento com a queixa de "ter dificuldades na alimentação e sofrer bullying na escola devido à falta de alguns dentes". Na anamnese o responsável apresentou diagnóstico médico de DE. Ao exame intrabucal observou-se microdontia dos caninos superiores e incisivo central superior esquerdo decíduos, e ausência dos demais elementos dentários. Como proposta de tratamento foram realizadas as reanatomizações com resina composta dos três dentes decíduos presentes em boca e confecção de prótese parcial removível (PPR) superior e prótese total (PT) inferiorpara substituir os dentes faltantes, trazendo a reabilitação estética e protética do paciente, bem como a melhora da sua autoestima e bem-estar. Discussão: A DE é uma doença hereditária de origem embrionária que acomete estruturas derivadas do ectoderma, como os cabelos, unhas, pele, glândulas e dentes. Manifestações dentárias importantes, como agenesia, podem ser verificadas nos pacientes portadores dessa síndrome. Conclusão: Diante disso, é extremamente importante que o cirurgião-dentista saiba identificar as principais características dessa síndrome, já que em muitos casos o mesmo é o primeiro profissional a ser procurado pelo paciente ou sua família. Uma vez estabelecido o diagnóstico, os pacientes acometidos devem receber uma abordagem multiprofissional para o tratamento dessa condição, a fim de promover o bem-estar físico, emocional e aumentar a qualidade de vida dos mesmos.

Aim: describe aclinical case of a patient with ectodermal dysplasia (ED), discussing the main characteristics of this syndrome and the proposed dental treatment. Case report: A 6-year-old male patient sought care complaining of "having difficulties in eating and being bullied at school due to missing some teeth". In the anamnesis, the person responsible presented a medical diagnosis of ED. The intraoral examination showed microdontia of the maxillary canines and deciduous maxillary left central incisor, and absence of other dental elements. As treatment proposals, reanatomizations were carried out with composite resin of the three deciduous teeth present in the mouth and construction of an upper removable partial denture (PPR) and a lower total denture (PT) to replace the missing teeth, bringing the aesthetic and prosthetic rehabilitation of the patient, as well as improving their self-esteem and well-being. Discussion:EDis a hereditary disease of embryonic origin that affects structures derived from the ectoderm, such as hair, nails, skin, glands and teeth. Important dental manifestations, such as agenesis, can be seen in patients with this syndrome. Conclusion:In view of this, it is extremely important that the dentist knows how to identify the main characteristics of this syndrome, since in many cases he is the first professional to be sought by the patient or his family. Once the diagnosis is established, affected patients should receive a multi-professionalapproach to the treatment of this condition, in order to promote physical and emotional well-being and increase their quality of life.

Expected and perceived burdens in patients receiving mandibular overdentures retained by one or two implants.

PURPOSE: This study aimed to assess patients' expected burdens before treatment and their perceived burdens after the surgical and prosthodontic procedures of mandibular overdenture treatment and to evaluate factors influencing patients' perceptions. METHODS: Data were collected from 47 participants enrolled in a randomized clinical trial comparing mandibular overdentures retained by one or two implants. A 20-item questionnaire measured on a four-point Likert scale covering the surgical and prosthetic treatment procedures was used to assess the patients' perception of the procedural burdens before (expected burdens) and immediately after (experienced burdens) each procedure. Operators' perceptions of intercurrences associated with the procedures were also assessed as an independent variable. RESULTS: Low levels of perceived burdens were observed both before and after treatment. The mean overall scores of 1.65 ± 0.46 and 1.53 ± 0.33 for expected and experienced burdens, respectively, indicated that most items ranged between "not burdensome at all" and "somewhat burdensome." Significant differences between expected and experienced burdens were found for eight items (P < 0.001). Considering the treatment stages, expected burdens scored higher in the pre-surgical, surgical, and prosthetic stages and lower in the post-surgical phase than experienced burdens. Overall, the experienced burdens were significantly affected by the expected burdens (P < 0.001) and operator's perceived burdens(P = 0.045). CONCLUSIONS: Treatments were associated with low levels of perceived burdens related to surgical and prosthodontic procedures and were highly correlated with the expected burdens before treatment. However, patients tend to overestimate the expected burdens before treatment, especially for surgical procedures.

Implant-retained overdenture delivery in 2 visits with a digital workflow.

The conventional method of fabricating implant-retained overdentures involves multiple steps and patient visits. However, the duplication of existing complete dentures could decrease the number of visits and increase patient satisfaction. An existing maxillary implant-retained overdenture was replaced for a 78-year-old man; the existing implant-retained overdenture and his face were scanned at the first visit. The scanned intaglio image was inverted to obtain a virtual maxillary cast and used to fabricate the metal framework of the replacement implant-retained overdenture. Prefabricated artificial teeth were arranged on a 3-dimensional trial denture created from the scan data of the existing implant-retained overdenture. The replacement implant-retained overdenture was fabricated on the metal framework by using the injection molding technique. By using these digital techniques, a stable and esthetic implant-retained overdenture was delivered in 2 visits.

Mandibular 3-implant overdenture: A clinical report of a novel design.

OBJECTIVE: To report on the use of a mandibular 3-implant overdenture with a novel implant distribution opposing a maxillary complete denture for the rehabilitation of an older edentulous patient. BACKGROUND: The use of oral implants with attachment systems of various numbers and designs to support removable partial and complete dentures is well documented with success and predictability. MATERIALS AND METHODS: An older edentulous patient with a mandibular implant-assisted removable partial denture was presented with failing remaining dentition. Teeth were extracted and a single midsymphyseal implant was placed. A mandibular overdenture on three implants with ball attachments in a tripod distribution was constructed to oppose a new maxillary complete denture made using a modified impression technique. RESULTS: Over 2 years of follow-up, no significant biological or mechanical complications were reported, and denture retention and stability remained optimum. CONCLUSION: Mandibular overdentures on three implants with ball attachments in a tripod distribution, opposing a maxillary complete denture, could be an alternative treatment option for the older edentulous patients.

Otimização das etapas de confecção do protocolo Branemark com carga tardia utilizando o guia multifuncional / Optimization of the Branemark protocol late load preparation steps using the multifunctional guide

O "planejamento reverso" em implantodontia busca alcançar um melhor prognóstico para a reabilitação do paciente, permitindo uma maior previsibilidade para o tratamento a partir do momento em que se planeja a reabilitação oral protética antes mesmo de planejar os implantes osseointegráveis. O dispositivo de resina acrílica chamado guia multifuncional representa a disposição final dos dentes na reabilitação e auxilia demasiadamente na etapa protética em casos em que não é possível a carga imediata. Ainda, otimiza o número de consultas do tratamento pois orienta a relação maxilomandibular, dimensão vertical e correta posição dos dentes. O presente trabalho tem como objetivo apresentar um caso clínico da utilização do guia multifuncional para moldagem dos implantes em caso de protocolo Branemark com dois tempos cirúrgicos, mostrando sua utilidade para diminuição do número de consultas na etapa de confecção da prótese total inferior definitiva. Diante dos resultados obtidos na realização do caso, foi possível concluir que nos casos de protocolo Branemark quando não é possível realizar a carga imediata, o guia multifuncional pode ser aproveitado e utilizado com sucesso, para a moldagem e confecção da prótese definitiva, diminuindo o número de consultas e otimizando o tratamento.

Reverse planning in implantology aims to improve patient's rehabilitation prognosis allowing greater treatment predictability from the prosthetic planning and before the implants installation. The acrylic resin device called multifunctional guide represents the final teeth disposition and is very useful in the prosthetic step when immediate loading is not possible. And it optimizes appointments treatment number since it guides the maxillomandibular relation, vertical dimension and correct teeth position. The aim of this study was to present a clinical case using the multifunctional guide for implant molding a two steps Branemark protocol, showing its usefulness to reduce the appointments number during the inferior total denture preparation step. Based on these results, it was possible to conclude that in Branemark protocol, when it immediate loading is not possible, the multifunctional guide can be used successfully for molding and making the final prosthesis, reducing the number of visits and optimizing treatment.

Evaluation of the Mean Bite Force and Masticatory Performance of Maxillary and Mandibular Complete Dentures vs Mandibular Implant-supported Over Denture.

AIM: To compare and evaluate the mean bite force and masticatory performance of conventional complete dentures (CD) in comparison with the lower implant-supported overdenture opposing an upper CD by using a strain gauge transducer and a test material respectively, in the same patient over a different period of time. MATERIALS AND METHODS: The study included 20 edentulous patients in the age range 45-65 years with a good general and oral health. In the first phase of the study, conventional CD were fabricated and delivered to each patient who participated in the study. A strain gauge transducer was used to analyze the maximum bite force and an agar test material was used to assess the masticatory performance using the sieve method. The existing lower denture was used to deliver a two-implant overdenture system and two implants were placed in the intermental-foraminal region of the mandible. One month after the delivery of implant-supported overdenture, the maximum bite force and masticatory performance were assessed as before. RESULTS: To test two independent variables, the data were analyzed statistically using an unpaired t-test. In comparison to the conventional upper and lower CD rehabilitations, the implant-supported lower denture and conventional upper CD rehabilitations resulted in statistically significant improvements in biting force and masticatory performance. CONCLUSION: Study findings demonstrate that the completely edentulous patients can be rehabilitated with the upper CD and lower two-implant supported overdenture system that offers improved biting force and masticatory performance than conventional upper and lower dentures. CLINICAL SIGNIFICANCE: Masticatory efficiency is one of the important indicators of functional state of stomatognathic system. Determination of individual masticatory performance has been used to ascertain the therapeutic effect of prosthetic device.

Digital and Analog Analysis of Occlusion in Conventional and Implant-Retained Complete Dentures: Preliminary Results of a Prospective Clinical Trial.

PURPOSE: To digitally evaluate the static and dynamic occlusion of patients treated with both removable conventional complete dentures (CCDs) and implant-retained removable overdentures (IODs) and to correlate two different methods of occlusal analysis. MATERIALS AND METHODS: Eleven totally edentulous patients were treated with bimaxillary CCDs. Later, mandibular CCDs were replaced by IODs retained by either two or four implants. The distribution of the occlusal contacts in static and dynamic occlusion was compared by means of the digital method (DM; T-Scan III) and the analog method (AM; articulating paper). Scores 0, 1, and 2 were assigned for inadequate, satisfactory, and adequate distribution of the occlusal contacts, respectively. The frequencies of scores were compared in relation to the types of denture by means of Fisher exact test (P < .05). The correlation between methods was assessed by means of the kappa agreement coefficient (κ) and the correlation coefficient phi (φ) (P < .05). RESULTS: Significant differences between CCDs and IODs were found in the right lateral mandibular movement (DM, P = .024; AM, P = .008), as well as in the left lateral mandibular movement (DM, P = .035). The methods of analysis of the occlusion showed a moderate agreement (κ = 0.604; P < .001) and a moderate correlation (φ = 0.605; P < .001). CONCLUSION: The digital and analog methods showed a significant agreement and moderate correlation, irrespective of the type of complete denture. The T-Scan III digital system seems to be a consistent and reproducible method to analyze occlusion.

Comparison of general satisfaction, oral health-related quality of life, and patient's self-assessment between mandibular single-implant overdentures and experimental removable complete dentures: A randomized crossover clinical trial.

Objective Patient satisfaction with single-implant overdentures (1-IODs) is unclear. This randomized crossover trial aimed to compare the general satisfaction, oral health-related quality of life, and patients' self-assessment between mandibular 1-IODs and experimental removable complete dentures (eRCDs). Methods New mandibular RCDs were fabricated for 22 patients with edentulous mandibles. After adapting to the RCDs, one implant was inserted in the mandibular midline. The participants were then randomly classified into groups 1 and 2. Group 1 received IODs for the first 2 months, while group 2 used eRCDs with a non-loaded implant in the midline. After 2 months, the treatment was switched. Four validated, patient-reported dental outcome measures were assessed: general satisfaction, Japanese version of the Oral Health Impact Profile for edentulous subjects (OHIP EDENT-J), General Oral Health Assessment Index (GOHAI), and Patient's Denture Assessment (PDA). The assessments were performed at the end of the IOD- and eRCD- use periods. Results General satisfaction was significantly higher during the IOD period (p = 0.002). Significant differences were observed in all domains of the OHIP, except orofacial pain (p = 0.084). Further, the total score (p<0.001) and the scores of the physical (p<0.001) and psychosocial functioning (p = 0.001) domains of the GOHAI differed significantly. The total PDA score (p = 0.001) and the scores of the function (p = 0.004), lower denture (p = 0.002), esthetics and speech (p = 0.026), and importance (p = 0.009) domains were significantly higher during the IOD period than during the eRCD period. Conclusion General satisfaction, oral health-related quality of life, and patient self-assessment scores were significantly higher for 1-IODs than for eRCDs. Clinical significance Within the limitations of this study, we found that mandibular single-implant overdentures may be an efficient alternative to mandibular experimental removable complete dentures due to higher general satisfaction, oral health-related quality of life, and patient self-assessment scores of dentures.

Effectiveness of silicone-based resilient denture liners on the patient-reported chewing ability: A randomized controlled trial.

PURPOSE: This randomized controlled trial (RCT) aimed to elucidate the effectiveness of silicone-based resilient denture liners on perceived chewing ability. METHODS: The RCT included completely edentulous patients on both the maxilla and mandible, who were willing to fabricate a new set of complete dentures. A random permuted block method (block size: 4) was used to assign groups to receive maxilla conventional complete denture and mandibular with either a conventional complete denture (CD) or complete demure relined with silicone-based resilient denture liner (RD). The patient-reported chewing ability of six foods, soybean curd, fish sausage, soybean sprout, cubic rice cracker, hard rice cracker, and dry squid, on a 100-mm visual analog scale was measured and reported at the final adjustment and three months after the final adjustment. Mann-Whitney U test was used to analyze the differences between the CD and RD (p < 0.05). RESULTS: Edentulous patients wearing mandibular complete denture with RD had a higher patient-reported chewing ability than those wearing a CD, but the fish sausage did not in the RD three months after the final adjustment. It also took three months for the patient-reported masticatory ability to improve for cubic rice crackers, hard rice crackers, and dry squid and to show a difference between the RD and CD groups. CONCLUSION: Although limited to some food types, mandibular complete dentures relined with silicone-based liners improved patient-reported chewing ability.

Comparison of the effect of conventional and implant-retained overdentures on brain activity and cognition in a geriatric population - A functional MRI study.

PURPOSE: This study aims to evaluate the effect of rehabilitation with complete dentures versus implant-retained overdenture on activity in various parts of the brain cognition in a geriatric edentulous population via Functional MRI (fMRI) studies and the Mini-Mental State Examination (MMSE). METHODS: Ten completely edentulous patients were rehabilitated with both complete dentures and two-implant retained overdentures for three months each. fMRI studies were performed for each modality during chewing and recall tasks at three time periods: T0: Completely Edentulous (CE) T1: after three months of wearing Conventional Complete Dentures (CD) and T2: after three months of wearing Implant-retained Overdentures (IOD). The Z scores obtained from the fMRI at these phases of examination were tabulated and correlated with MMSE scores obtained at the corresponding time periods. RESULTS: Z scores obtained during the memory recall tasks at T2 were the greatest (Prefrontal Cortex (p=0.059) and Hippocampus (p=0.036). The MMSE scores obtained were significantly higher for the IODs when compared to the CDs and Baseline values (p < 0.05). CONCLUSION: IODs may potentially result in superior sensory feedback in edentulous patients and lead to improved cognitive performance when compared to conventional complete dentures.

Immediately loaded single-implant mandibular overdentures compared to conventional complete dentures: A cost-effectiveness analysis.

BACKGROUND: In recent years, the single-implant mandibular overdenture (SIMO) has been proposed as an alternative to more complex overdenture designs as a simplified implant intervention for edentulous patients. OBJECTIVE: The aim of this study was to run a cost-effectiveness analysis alongside a randomized clinical trial comparing the SIMO and the conventional complete denture (CCD) treatment. Imediately loaded external hexagon implant and ball attachment were used for the overdenture goup. Direct costs related to therapies were identified and valuated throughout a 1-year period after delivery, in Brazilian currency (R$) and converted into international dollars (I$) using purchase power parity exchange rates. Treatment effectiveness was measured using the OHIP-Edent and satisfaction scores for calculation of incremental cost-effectiveness ratios (ICER). RESULTS: Outcomes were assessed at the 1-year follow-up for 65 patients (CCD=34; SIMO=31). Overall OHIP-Edent and satisfaction scores improved significantly in the SIMO group, while remained unchanged in the CCD group. The mean overall costs were R$1,179.04 (I$590.99) for the CCD group and R$2,127.91 (I$1,068.20) for the SIMO group - 80.7% incremental cost for SIMO. The ICER calculation for SIMO treatment showed a mean cost of I$48.20 for 1-point reduction in OHIP-Edent scores, and I$12.56 for 1-point increase in satisfaction score. CONCLUSIONS: Findings support the effectiveness of this simplified and low-cost implant intervention for edentulous patients. SIMO also seems a cost-effective alternative to the CCD and the relatively low incremental cost may potentially increase the utilization of dental implants among older subjects, especially those with limited financial resources. CLINICAL SIGNIFICANCE: The immediately loaded single-implant mandibular overdenture was superior to the conventional complete denture in terms of patient-reported outcome measures at a low incremental cost.