Optimal Number Of Implants Research Articles

Revisiting maxillary implant overdentures in 2022: A topic review

The challenge for general dental practitioners to provide maxillary implant overdenture treatment for their patients is complicated by multiple, diverse parameters, compared to mandibular implant overdentures. This topic review on maxillary implant overdentures takes into consideration the specifications and challenges of different prosthodontic treatment options for clinicians in 2022. A broad search of the published literature was performed using MEDLINE and PubMed to identify pertinent articles published in English from 1990 to 2021. From an original total of 1176 titles, 106 references were selected. They were reviewed and categorized with respect to seven factors related to the prosthodontic design. These were interarch restorative space, implant number, implant distribution and spread, overdenture base reinforcement, palatal coverage, selection of attachment system and splinted/unsplinted prosthodontic designs. They influence clinical and patient outcomes in terms of implant and prosthesis success, support, retention, prosthodontic maintenance and satisfaction. Maxillary implant overdentures are a reliable treatment option for general dental practitioners, once competent with mandibular overdentures. The decision for adequate treatment for each individual patient is influenced by a diversity of parameters with clinicians needing to have a thorough knowledge and understanding of the anatomic obstacles, facial aesthetics, phonetics, and complete denture principles for essential pre-surgical and prosthodontic treatment planning. Currently there is no optimal number of implants, nor preferred attachment system, regardless of palatal coverage design. There are emerging trends of more evidence for use of reduced number of unsplinted implants simplifying procedures for general dental practice.

A computational model to design neural interfaces for lower-limb sensory neuroprostheses

BackgroundLeg amputees suffer the lack of sensory feedback from a prosthesis, which is connected to their low confidence during walking, falls and low mobility. Electrical peripheral nerve stimulation (ePNS) of upper-limb amputee’s residual nerves has shown the ability to restore the sensations from the missing limb via intraneural (TIME) and epineural (FINE) neural interfaces. Physiologically plausible stimulation protocols targeting lower limb sciatic nerve hold promise to induce sensory feedback restoration that should facilitate close-to-natural sensorimotor integration and therefore walking corrections. The sciatic nerve, innervating the foot and lower leg, has very different dimensions in respect to upper-limb nerves. Therefore, there is a need to develop a computational model of its behavior in response to the ePNS.MethodsWe employed a hybrid FEM-NEURON model framework for the development of anatomically correct sciatic nerve model. Based on histological images of two distinct sciatic nerve cross-sections, we reconstructed accurate FEM models for testing neural interfaces. Two different electrode types (based on TIME and FINE) with multiple active sites configurations were tested and evaluated for efficiency (selective recruitment of fascicles). We also investigated different policies of stimulation (monopolar and bipolar), as well as the optimal number of implants. Additionally, we optimized the existing simulation framework significantly reducing the computational load.ResultsThe main findings achieved through our modelling study include electrode manufacturing and surgical placement indications, together with beneficial stimulation policy of use. It results that TIME electrodes with 20 active sites are optimal for lower limb and the same number has been obtained for FINE electrodes. To interface the huge sciatic nerve, model indicates that 3 TIMEs is the optimal number of surgically implanted electrodes. Through the bipolar policy of stimulation, all studied configurations were gaining in the efficiency. Also, an indication for the optimized computation is given, which decreased the computation time by 80%.ConclusionsThis computational model suggests the optimal interfaces to use in human subjects with lower limb amputation, their surgical placement and beneficial bipolar policy of stimulation. It will potentially enable the clinical translation of the sensory neuroprosthetics towards the lower limb applications.

Does number of implants or type of attachment affect patient satisfaction with implant-retained mandibular overdentures?

Aim This study aimed to determine, from the patients’ perspective, the optimal number of implants and the type of attachment used to support a mandibular overdenture. Materials and methods This study was conducted with 166 patients who had received new implant-retained overdentures (IODs) in the mandible and conventional total prostheses in the maxilla, and have been using for at least 1-year. Three types of attachment (ball attachment, bar holder, and locator) were connected to either two or four implants. Patients completed the OHIP–14 questionnaire, and the results were statistically analyzed. Results Patients were, in general, satisfied with their mandibular IODs (OHIP-ADD: 7.07 ±9.09, OHIP-SC: 0.95 ±2.11). While the satisfaction rate was higher for males (P 0.05). Higher satisfaction was observed for 4-implant support (P = 0.014), especially with bar holders (OHIP-SC: 0.13 ±0.43). No difference was found between the locator and ball attachment in prostheses with 2-implant (P > 0.05). Conclusion Four implant-support, in particular, with bar-holders, exhibited higher satisfaction. There was no difference between locator and ball attachment in terms of patient satisfaction.

Stabilized Record Base for Implant Treatment

It is important to obtain an accurate interocclusal record for the restoration of patients undergoing implant treatment. Atrophic alveolar bone in the mandible not only limits the placement of implants, but also contributes to deficient ridge morphology resulting in unstable record bases. Securing the record base to the implants is a useful way to obtain an accurate registration. The technique presented in this article uses two widely spaced implants as the optimal number of implants to stabilize record bases.