Assessment of masticatory function of mandibular implant-supported overdenture wearers: A 3-year prospective study

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.

Clinical Report on an Implant-Supported Overdenture in a Parkinson's Patient

Speaking, chewing, and swallowing difficulties can result from Parkinson's disease (PD), which frequently affects the oro-pharyngeal muscles. The reduction in food and hydration intake that is unavoidable leads to a worsening of neurological symptoms. Patients with Parkinson's disease experience significant challenges when adjusting to wearing entire dentures. Each of these problems presents a considerable challenge for the doctor in terms of prosthodontic rehabilitation. This case study describes how a patient with Parkinson's disease was able to employ flexible removable partial dentures supported by implants to replace both their full and partial set of missing teeth. A well-made prosthesis will help the patient with their psychological, functional, and aesthetic impairments.

Functional performance and impact on the quality of life of three treatment strategies for mandibular edentulism: Results of a parallel 3-group cross-sectional study

OBJECTIVES

This parallel cross-sectional study compared masticatory function and patient-centered outcomes among 3 removable treatment strategies for mandibular edentulism.

METHODS

Thirty-six edentulous participants rehabilitated using 3 removable treatment strategies for mandibular edentulism were allocated to one of the three groups (n=12): CCD (control), 2-IMO, and 3-IMO. Narrow diameter implants were installed using single-stage surgery and conventionally loaded with stud abutments. After 3 months of usage, the quality of life, maximum bite force, and masticatory function were evaluated. Data were analyzed with the Kruskal-Wallis test and post hoc pairwise Mann-Whitney tests with Bonferroni correction (α=0.05).

RESULTS

The 2-IMO and 3-IMO wearers did not show significant differences in any outcome, except for the 2 domains of 3-IMO wearers quality of life that obtained better Pain and General Performance scores. Both IMO groups presented significantly higher maximum bite force than CCD wearers. The 2-IMO wearers showed superior outcomes to the CCD group in all outcomes of the masticatory performance test and the X50, B and ME5.6 outcomes of the swallowing threshold test (p = 0.01), while 3-IMO participants only showed superior masticatory performance in terms of lower X50 values (19.86%, p = 0.02) and higher ME 2.8 (141.15%, p = 0.04) than CCD wearers.

CONCLUSIONS

Compared to 2-IMO wearers, 3-IMO wearers report superior impact of treatment on daily living activities in the Pain and General Performance domains. 2-IMO and 3-IMO wearers showed no significant differences between them for all evaluated bite force and masticatory function parameters.

CLINICAL SIGNIFICANCE

Although overdentures retained by 3 implants (3-IMO) provide biomechanical advantages over those retained by 2 implants (2-IMO), superior clinical and functional effectiveness is not yet proven.

Oral function in completely edentulous patients rehabilitated with implant-supported dental prostheses: A systematic review and meta-analysis

OBJECTIVES

This review evaluated the effects of rehabilitation with implant-supported prostheses on the oral function of completely edentulous adults.

MATERIALS AND METHODS

Systematic literature searches were performed to identify records reporting on oral function in completely edentulous adults rehabilitated with implant-supported prostheses. Meta-analyses were performed on various outcomes including bite force, masticatory performance, muscle activity, mandibular movement/chewing pattern, and salivary flow.

RESULTS

5507 records were identified. Thirty studies qualified for data extraction and analysis. The kappa (𝛋) for the search and identification strategy ranged between 0.50 and 1.00. Meta-analysis was performed grouping the studies by outcomes and split by time points of 6-12 months, 12-36 months, and >36 months after implant therapy. The meta-analyses revealed a significant improvement in oral function of completely edentulous adults after rehabilitation with implant-supported prostheses at 6-12 months (Z = -4.895, p < .001; 95% CI: -0.703, -0.301; τ2  = .609; Q = 114.953, df = 17, p < .001; I2  = 85.2%), at 12-36 months (Z = -4.886, p < .001; 95% CI: -0.580, -0.248; τ2  = .908; Q = 280.611, df = 35, p < .001; I2  = 87.5%) and at more than 36 months (Z = -9.108, p < .001; 95% CI: -1.472, -0.951; τ2  = .019; Q = 7.918, df = 7, p = .340; I2  = 11.6%). The included studies demonstrated a low to moderate risk of bias.

CONCLUSIONS

This systematic review concluded that the oral function of completely edentate adults significantly improved with implant-supported/retained prostheses, even when only one jaw received implant therapy. Therefore, implant therapy should be promoted for edentulous adults to alleviate the shortcomings of conventional complete removable dental prostheses.

Single mandibular implant study - chewing efficiency - 5-year results from a randomized clinical trial using two different implant loading protocols

PURPOSE

To investigate the chewing efficiency of edentulous patients wearing complete dentures, treated with a single implant in the mandible, placed underneath the existing mandibular dentures, using two different loading protocols (immediate loading or conventional loading), over an observation period of 5 years.

METHODS

One-hundred and fifty-eight (158) edentulous seniors aged 60-89 years received an implant in the midline of the lower jaw and were randomized either to the immediate loaded group A (n=81) or the conventional loaded group B (n=77). Chewing efficiency was obtained before treatment, one month after implant placement during the submerged healing phase (only group B) and 1, 4, 12, 24 and 60 months after implant loading.

RESULTS

After 5 years, chewing tests from 89 patients (45 in the immediate loading group and 44 in the conventional loading group) were available for every recall visit and thus statistically analyzed. The chewing efficiency increased over time in both groups. A significant increase was observed up to 4 months after loading (p≤0.05). Later, chewing efficiency further increased, but not significantly. Between the two loading protocols, chewing efficiency did not differ significantly (p>0.05) at any follow-up investigation.

CONCLUSION

A single mandibular implant placed underneath existing mandibular dentures improves chewing efficiency of edentulous patients significantly over an observation period of 5 years, irrespective of the loading protocol.