A comparative evaluation of masticatory load distribution in different types of prosthesis with varying number of implants: A FEM analysis.

Aim: To identify the optimal number and position of implants to reduce stress concentration on the implant, denture, and attachment system for sustaining an overdenture prosthesis. Materials and methods: By incorporating one to eight indigenous implants with bar-type attachments, eight 3D finite element models of mandibular overdentures were created. All models received a 200 N vertical load, and the biomechanical characteristics of peri-implant bone were assessed. Result: The study observed that with a vertical load of 200 N, the maximum equivalent stress around peri-implant tissue in all models was within the physiological tolerance threshold of bone. The von Mises stress values ranged from 116.18 MPa to 536.7 MPa. Conclusion: The three-implant-supported overdenture model revealed superior peri-implant stress, stability, cost-effectiveness, and hygiene maintenance outcomes. Placing a third implant in the mid-symphysis region may offer a practical solution to reduce rotations in two-implant-supported overdentures.

Treatment Intricacies in Mandibular Implant-Supported Rehabilitation of a Patient With Down Syndrome: A Clinical Report.

Edentulism is considered a poor health condition and may compromise the quality of life. Prosthodontic replacement of missing teeth results in significant improvement of oral functions. Treating a patient with Down syndrome can pose clinical challenges in handling the emotional aspect as well as in rendering treatment. Careful oral analysis and diagnosis of the existing conditions in such patients will enable and pave the way for clinically acceptable treatment results. This clinical report describes the challenges encountered in the prosthodontic management of an edentulous young patient with Down syndrome.

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.

A Case Report on Implant-Supported Telescopic Prosthesis-A Gerodontic Enhancement.

One of the most challenging and demanding endeavors in the field of prosthodontics is the rehabilitation of an edentulous mandible. Implants have been used to support mandibular or maxillary prosthetic rehabilitation. Advantages of using implants are increased retention, increased chewing ability, and also easy access to oral hygiene procedures. For decades, the use of telescopic and conical crowns are in practice to connect natural teeth and not many cases have been reported in the literature of telescopic crowns placed on implants to support the prosthesis. Telescopic crowns provide the best possible distribution of force to the abutment teeth and can improve the patient's oral health-related quality of life. The use of telescopic crowns as attachments for implant-supported overlying prostheses may be a viable treatment option for edentulous mandible. The functional and the aesthetic enhancement by telescopic retainers are favorable features for many challenging situations. This case report discusses a 60-year-old male, who reported to the department of prosthodontics with three implants and two bi-cortical screws that were placed in a completely edentulous mandibular arch by a private practitioner one year back and this situation was prosthodontically managed by us with an implant-supported telescopic removable prosthesis.

Comparing the functional efficiency of tooth-supported overdentures and implant-supported overdentures in patients requiring oral rehabilitation: A systematic review.

The aim of this article is to compare the functional efficiency of tooth-supported overdentures and implant-supported overdentures in patients requiring oral rehabilitation. The comparative quantification of the improvement in functional efficiency is very difficult to assess because of the variations in the study designs like the age of the population studied, the male-to-female ratio, the outcome measures used, the clinical setting in which the implant therapy was provided, oral status of the subjects included and the type of implant therapy provided. In this systematic review, the articles included compared the functional efficiency by assessing the bite force, chewing efficiency, electromyographic (EMG) changes measured by EMG analysis, and patient satisfaction for subjects who have been rehabilitated with either a tooth-supported overdenture or an implant-supported overdenture. This will help the clinicians to better plan the treatment, keeping in mind the long-term prognosis for that particular patient.

A 5-Year Retrospective Study Evaluating Periodontal Health and Oral Health-Related Quality of Life of Implant-Supported Overdentures With Locator and Magnetic Attachments.

This study compared peri-implant vertical bone loss, the periodontal index, prosthodontic maintenance requirements and oral health-related quality of life (OHQoL) of patients using mandibular implant-supported overdentures with 2 different attachment systems after an average of 5 years of use. Sixteen mandibular overdenture patients with magnet attachments (group 3), 24 with implant-supported mandibular overdentures with Locator attachments (group 2), and 25 conventional complete denture patients (group 1) were included in the study. The existing at least 5 years old dentures of all patients were evaluated for prosthodontic maintenance by the same prosthodontist and the patients were administered the oral health impact profile-14-Turkish version (OHIP-TR-14) questionnaire. Peri-implant tissue health was evaluated clinically in terms of plaque scores, bleeding scores, probing depth, and gingival index. Radiographic evaluation was performed in terms of peri-implant vertical bone loss. Radiographic evaluations were performed 5 years after overdenture insertion. There were no statistically significant differences between the groups in terms of total OHIP-TR-14 scores (P > .05). Although the average vertical bone resorption measured in group 2 at the end of 5 years was 1.38 mm, there was an average vertical bone loss of 1.45 mm in group 3, but this difference was not statistically significant (P > .05). Among the periodontal health indicators, there were no statistically significant differences in the mean values for periodontal indexes. According to results of the study, there were no differences in peri-implant vertical bone loss in groups 2 and 3, in periodontal health in mandibular overdentures with groups 2 and 3, or between total OHIP-TR-14 scores of patients in all groups.

The effect of flexible acrylic resin on masticatory muscle activity in implant-supported mandibular overdentures: a controlled clinical trial.

BACKGROUND: It is not yet clear from the current literature to what extent masticatory muscle activity is affected by the use of flexible acrylic resin in the construction of implant-supported mandibular overdentures. OBJECTIVE: To compare masticatory muscle activity between patients who were provided with implant-supported mandibular overdentures constructed from flexible acrylic resin and those who were provided with implant-supported mandibular overdentures constructed from heat-cured conventional acrylic resin. METHODS: In this clinical trial, 12 completely edentulous patients were selected and randomly allocated into two equal treatment groups. Each patient in Group 1 received two implants to support a mandibular overdenture made of conventional acrylic resin. In Group 2, the patients received two implants to support mandibular overdentures constructed from "Versacryl" flexible acrylic resin. The maxillary edentulous arch for patients in both groups was restored by conventional complete dentures. For all patients, masseter and temporalis muscle activity was evaluated using surface electromyography (sEMG). RESULTS: The results showed a significant decrease in masticatory muscle activity among patients with implant-supported mandibular overdentures constructed from flexible acrylic resin. CONCLUSION: The use of "Versacryl" flexible acrylic resin in the construction of implant-supported mandibular overdentures resulted in decreased masticatory muscle activity.

Enhancing the zone of keratinized tissue around implants.

Presence or absence of a minimal zone of keratinized tissue around dental implants has been a matter of controversy. However, a consensus exists that a thick zone of keratinized zone around implants provides a prosthetic friendly environment, facilitates precise prosthetic procedures, allows oral hygiene maintenance, resists recession, and enhances esthetic blending. The aim of the present case series was to increase the zone of keratinized soft tissue around dental implants supporting overdentures. Three different surgical techniques modified palatal roll technique with and without apical positioning and connective tissue graft (CTG) were used to achieve this goal. There was a significant gain of keratinized soft tissue with all the three techniques, which remained stable over a period of 6 months. Modified palatal roll technique with and without apical positioning and CTG are simpler surgical techniques, which can be successfully and predictably used for increasing the zone of keratinized tissue around implants.

OHRQoL, masticatory performance and crestal bone loss with single-implant, magnet-retained mandibular overdentures with conventional and shortened dental arch.

PURPOSE: The aim of this study was to assess the use of single implant-supported, magnet-retained mandibular overdentures to improve the oral health-related quality of life (OHRQoL) and masticatory performance of patients wearing conventional complete dentures. The study also aimed at comparing the OHRQoL, masticatory performance, and crestal bone loss with two different types of overdenture prosthesis. MATERIALS AND METHODS: Ten completely edentulous patients with atrophic mandibular residual alveolar ridges and having difficulty coping with technically adequate mandibular dentures were selected for implant-supported overdentures (ISOD). To assess the success of the implant fixture clinically, a crossover study design was followed, and the patients were divided into two groups. Group A received ISOD with conventional complete dental arch, and group B received ISOD with a shortened dental arch for the first 3 months and vice versa for the next 3 months. The OHRQoL was measured with the OHIP-49 questionnaire, and masticatory performance was assessed with the sieve method using peanuts as test food. Peri-apical radiographs were taken to evaluate the crestal bone loss. RESULTS: A significant improvement was seen both subjectively and objectively when conventional complete dentures were modified to implant-supported prosthesis. When comparing the implant overdenture prosthesis, patients were more satisfied with conventional arch than with the shortened dental arch. In the first 3 months following implant placement, less bone loss was seen with the shortened dental arch overdenture (P < 0.05). CONCLUSION: Single implant-supported, magnet-retained mandibular overdentures significantly improve the OHRQoL of completely edentulous patients.

Nutritional and anthropometric analysis of edentulous patients wearing implant overdentures or conventional dentures

As masticatory efficiency diminishes drastically in edentulous patients, several researchers have studied over the past two decades how dietary intake varies when different types of oral rehabilitation are provided. Since the use of implants to support prostheses in edentulous mandibles has been shown to significantly improve masticatory performance, the question remains as to whether this improvement will influence the nutritional status. The purose of this study was to evaluate the nutritional status of edentulous patients who randomly received either a mandibular conventional denture (CD) or an implant-supported overdenture (IP) 1 year previously. Weight, height, body composition and handgrip strength measurements were collected for analysis. Blood tests were performed to measure plasma parameters of diet intake. Participants responded to a Food Frequency Questionnaire and a Masticatory Function Questionnaire. Fifty-three people participated (58 percent men, 42 percent women; mean age = 53). Body composition indicators as well as plasma parameters were generally within normal range, and no statistically significant difference (p>0.05) was found between the groups. Patients in the CD group had significantly lower ratings for items regarding difficulty in chewing (p<0.05), but no significant difference was found for dietary intake (p>0.05). Although the CD wearers reported having more difficulty in chewing hard foods, both groups appeared to have a similar nutritional status.

O uso de implantes para suportar próteses em pacientes edêntulos completos causa uma melhora significativa na performance mastigatória desses indivíduos. Contudo, a influência desse benefício no estado nutricional do paciente ainda não está completamente estabelecida. Esse estudo avaliou o estado nutricional de pacientes desdentados completos reabilitados com próteses totais convencionais (grupo CD) ou com próteses totais implanto-suportadas (grupo IP) na mandíbula. Foram coletados dados sobre composição corporal e uma amostra de sangue para análise. Os participantes responderam a um questionário sobre freqüência alimentar (QFA) e outro sobre habilidade mastigatória e método de preparo dos alimentos (QMF). A amostra foi composta de 53 participantes selecionados a partir de um estudo randomizado, sendo 58 por cento homens e 42 por cento mulheres, com idade média de 53 anos. Os indicadores de composição corporal se encontraram dentro da normalidade e sem diferenças significativas (p>0.05). O grupo CD obteve valores significativamente diferentes para itens do QMF sobre dificuldade de mastigar (p<0.05). Os dados do QFA e o resultado do exame de plasma estavam dentro dos níveis normais, e os valores entre os grupos foram semelhantes (p>0.05). Embora os participantes que receberam prótese total convencional tenham relatado maior dificuldade de mastigar alimentos duros, os dois grupos apresentaram estados nutricionais semelhantes.