Evidence-Based Criteria for Differential Treatment Planning of Implant Restorations for the Mandibular Edentulous Patient

Peri-implant tissue health and patient satisfaction of vertical versus inclined posterior implants used to support overdentures with bar attachments. A one-year randomized trial

INTRODUCTION

This study aimed to evaluate peri-implant tissue health and patient satisfaction of vertical and inclined posterior implants for mandibular bar overdentures.

MATERIALS AND METHODS

Thirty edentulous participants received four implants in the interforaminal area of the mandible. The patients were randomly assigned into two equal groups; (1) vertical group (control): all implants were inserted vertically parallel to each other. Inclined group (study): the anterior implants were placed vertically, and the posterior implants were tilted 30° distally. Hader bar attachment with two 7 mm-distal cantilevers (vertical group) and without cantilevers (inclined group) was used to connect the implants to mandibular overdentures. Peri-implant tissue health (Plaque [PL] and gingival [GI] indices, pocket depth [PD], and crestal bone loss [CBL]) were evaluated after denture insertion (T0), 6 (T6), and 12 (T12) months after insertion. Patient satisfaction was evaluated using a visual analog scale after 12 months.

RESULTS

At T12, the vertical group showed significantly higher PL, PD, and CBL than the inclined group for anterior (p < 0.037) and posterior (p < 0.017) implants. The vertical group showed significantly higher GI than the inclined group for anterior implants (p = 0.003), and the inclined group showed significantly higher GI than the vertical group for posterior implants (p = 0.016). The inclined group showed significantly higher scores for general satisfaction (p = 0.049), prosthesis as a part of you (p = 0.013), appearance (p < 0.001), stability (p = 0.002), ease of cleaning (p < 0.001), and comfort (p = 0.001) than the vertical group.

CONCLUSION

Inclined posterior implants used to support mandibular bar overdentures are recommended than vertical implants, as it was associated with improved patient satisfaction and peri-implant tissue health.

Prosthetic failures in dental implant therapy

Both fixed and removable implant‐supported prostheses are well‐established methods for replacing missing teeth in partially or fully edentulous patients. Numerous systematic reviews have been performed in recent years to evaluate the survival and complication rates of implant‐retained fixed dental prostheses and implant‐retained overdentures, displaying high 5‐year survival rates ranging from 97.1% for fixed dental prostheses to 95%‐100% for implant‐retained overdentures. However, the survival rates only represent the prostheses remaining in use for a defined follow‐up time, and do not account for the potential prosthetic complications that may have arisen and influence the general success of the implant treatment. The most common technical complications of fixed implant‐retained single crowns are crown fracture, fractures of ceramic implant abutments, and esthetic problems. The predominant technical complication at multiple‐unit, implant‐retained fixed dental prostheses is fracture/chipping of the veneering ceramic. Reported technical complications for implant‐retained overdentures are overdenture fracture or chipping of the veneer materials, whereas mechanical complications include implant fracture, attachment failure, and attachment housing or insert complications. To reduce the risk of such failures, a comprehensive pretreatment diagnostic work‐up is essential, including defining the prosthetic goal with the aid of a wax‐up or set‐up and the associated ideal, prosthetically oriented three‐dimensional implant position. Furthermore, selection of the ideal type of prosthesis, including the respective implant components and materials, is important for clinical long‐term treatment success.

A 5-Year Satisfaction Outcome Study of Patients Receiving Six-Implant-Supported Fixed Prosthesis

The aim of the study was to analyze the satisfaction of patients treated with a protocol of six-implant-supported fixed prosthesis (6IFP) throughout 5 years of service. This retrospective study collected the data of all patients who had full-arch rehabilitations using 6IFP and followed them for 5 years. After applying the research inclusion/exclusion strategy, 37 cases were finally included in the study. All the patients had no previous complete dentures because they were partially edentulous, not interested in pursuing complete denture rehabilitation, had immediate dental extractions, implantation used the 2-stage protocol, and there was minor peri-implant socket grafting. Cases with severe bone loss that required extensive grafting were excluded. A total number of 222 implants were placed in the maxillary or mandibular arches in a total of 37 patients. The data presented the satisfaction outcomes concerning mastication, phonetics, and comfort during the first 5 years of the recall plan. The former was achieved based on the clinical record reviews, follow-up visits, and recall phone calls at the preoperative stage as well as annually thereafter. The mean satisfaction rate was 94.5%, with a mean record of 8.21 ± 1.7 out of 10, there was no gender predilection significance, and no age range variation significance was validated. Regarding the smoking status, the t-test score exhibited no significant effect on phonetics and mastication (p = 0.12, p = 0.16, respectively), whereas comfort was found to be significantly affected (p = 0.03). The comfort level was found to be slightly less at the immediate postoperative period among smokers when compared to non-smokers. In conclusion, partially edentulous patients who received the rehabilitation plan of arch dental extractions, six immediate implantations, and delayed prosthetic loading were found to be highly satisfied.

Masseter muscle activity of conventional denture, fixed prosthesis, and milled bar overdenture used for All-on-4 implant rehabilitation: A within-subject study

PURPOSE

to examine the electromyographic (EMG) activity of the masseter muscles in patients with conventional dentures and compare it to EMG activity of fixed prosthesis, and milled bar overdentures used to rehabilitate mandibular atrophied ridges according to the All-on-4 concept.

METHODS

Eighteen edentulous subjects with atrophied mandibles received complete dentures (CD, control). After 3 months, four implants were installed between the mental foramina according to the "All-on-4" protocol and loaded immediately. After osseointegration, fixed prostheses (FPD) or milled bar overdentures (MBO) were given to the patients in random order. Primary (amplitude), and secondary (chewing rate, time of the masticatory cycle, time of masticatory burst, and masticatory time) outcomes were evaluated 3 months after using CD, FPD, and MBO. The evaluations were made during mastication of carrot (hard) and cake (soft) foods.

RESULTS

FPD and MBO were associated with a significantly higher (amplitude, time of masticatory cycle, and time of masticatory burst), and significantly lower (chewing rate and masticatory time) compared with conventional dentures. Primary and secondary outcomes did not differ between FPD and MBO. Carrot had significantly higher amplitude, chewing rate, time of masticatory burst, and masticatory time than cake, while cake had a significantly higher time of masticatory cycle than carrot.

CONCLUSIONS

Within limitations of this study, milled bar overdentures for All-on-4 implant rehabilitation of atrophied mandible is not less efficient than fixed prostheses in terms of electromyographic activity of the masseter muscle. Both prostheses significantly improve muscle activity, chewing rate, time of masticatory cycle, time of masticatory burst, and masticatory time compared with conventional dentures.

Use of a digitally guided triple technique for bone reduction, implant placement, and immediate interim prostheses in complete-arch implant surgery

A digitally guided triple technique for bone reduction, implant placement, and immediate interim prostheses in complete-arch implant surgery is presented. This technique integrates bone reduction and implant placement information into a dual-function surgical template and introduces a digital approach to fabricating immediate interim implant-supported fixed dental prostheses with the same occlusal relationship as the one evaluated with diagnostic removable prostheses.

A CAD-CAM technique for conversion of interim-to-definitive restoration in patients with complete edentulism

An interim restoration is a prototype for the definitive prosthesis and preserves the occlusal information and the original vertical dimension of the occlusion. Several techniques have been developed to transfer the information from implant-supported fixed interim to definitive restoration. However, these conventional techniques have limitations, and they are time-consuming, require making impressions and stone casts, and mounting in an articulator. The purpose of this article was to describe a digital technique to accurately transfer the information from complete-arch implant interim restoration to definitive restorations without using definitive casts.

Use of a CAD-CAM poly(methyl methacrylate) interim prosthesis for direct intraoral splinting

This article describes a technique where an interim computer-aided design and computer-aided manufacturing (CAD-CAM) prosthesis is milled from a poly(methyl methacrylate) blank to confirm esthetics, occlusion, function, phonetics, and accessibility for oral hygiene. The interim prosthesis is then sectioned and reconnected intraorally with autopolymerizing acrylic resin. This interim prosthesis is used to fabricate the definitive stone cast. The interim prosthesis is then scanned with a laboratory scanner. By applying this technique, the implant positioning can be related to the occlusal plane, the contours of the teeth, and the flange. The clinician can more effectively design the definitive prosthesis because the location of the implants and the exact contours of the teeth are all captured in a single digital file.

Multidisciplinary Approach in the Management of a Complex Case: Implant-Prosthetic Rehabilitation of a Periodontal Smoking Patient with Partial Edentulism, Malocclusion, and Aesthetic Diseases

Complex periprosthetic cases are considered as challenges by clinicians. Clinical and radiographic parameters should be considered separately to make the right choice between an endodontically or periodontally compromised treated tooth and implant. Therefore, in order to decide whether the tooth is safe or not, data that have to be collected are specific parameters of both the patient and the clinician. In addition, the presence of periodontal, prosthetic, and orthodontic diseases requires patients to be set in multidisciplinary approach. The aim of this case report is to describe how the multidisciplinary approach could be the best way to manage difficult cases of implant-prosthetic rehabilitation. How to rehabilitate with fixed prosthesis on natural teeth and dental implants a smoker patient who presents with active periodontitis, multiple edentulous areas, dental malocclusion, and severe aesthetic problems was also described.