Comparative evaluation to study the effect of implant support on complete fixed dental prosthesis fabricated with peek framework when implants placed in all-on-4 and all-on-6 situation, by strain gauge analysis and finite element analysis - An in vitro study

Aim

To evaluate and compare the strain development and distribution of maxillary implant-supported complete fixed dental prosthesis (ISCFDP) with computer-aided design-computer-aided manufacturing milled PEEK BIO-HPP superstructure when placed using All-on-4 and All-on-6 situation using a strain gauge and finite element analysis (FEA).

Setting and Design

This is an in vitro study to evaluate and compare the stress minimization and strain developed at implant in premolar and in two clinically simulated situation of All-on-4 and All-on -6 ISCFDP.

Materials and Methods

The study involved converting a human skull into. stl format to create 3D-printed stereolithography models with a modulus of elasticity closer to bone. Implants were placed in two models (M1 nad M2) in incisor, premolar, and pterygoid regions. A fixed dental prosthesis framework was fabricated on both models, and strain gauge sensors were attached.

Statistical Analysis Used

Descriptive and analytical statistics were done. The normality of data was analyzed by the Shapiro-Wilk test.

Results

The results obtained were tabulated and it showed strain around the neck of ISCFDP under 100N configuration in strain gauge analysis. Stress was found more in the molar region when compared to the premolar region. This design showed that the largest stress around the neck of ISFDP under 100 N load was found more in the premolar region when compared to the molar region due to the reduction of stresses in the pterygoid region in FEA.

Conclusion

In the present study, strain gauge analysis at 100 N for loading at the premolar and molar region shows the reduced strain on tilted implants in All-on-6 situation due to stress dissipation to the terminal pterygoid implant using strain gauge.

Clinical outcomes of implant-supported prosthetic rehabilitation of severely atrophic maxilla: A systematic review

Aim

The purpose of this systematic review is to evaluate the clinical outcomes for the various methods of rehabilitation of a severely atrophic maxilla with the help of implant-supported fixed prosthesis.

Materials and Methods

The relevant publications published between 2013 and 2022 and written only in English were identified using an electronic search. The primary research question for this study was developed based on the PICO framework, which stands for population, intervention, control, and outcomes which was "What are the clinical outcomes of implant-supported prosthetic rehabilitation in patients with severely atrophic maxilla?" The relevancy of the articles was confirmed by examining their titles, abstracts, and complete texts to determine whether they satisfied the requirements for inclusion. Utilizing specialized study design-related bias assessment forms, the risk of bias was evaluated.

Results

The database search resulted in 1568 results; however, 1529 of them were eliminated because of insufficient, duplicate, or missing data. Additionally, manual searching yielded 11 articles. After 50 full-text papers were assessed for eligibility, 17 articles were eliminated. Thus, 33 studies in total are included in the current systematic review. Risk of bias analysis and GRADE evidence analysis were performed. Data were found to be heterogeneous and thus meta-analysis could not be done and narrative synthesis is presented.

Conclusion

The patient's condition and the clinician's expertise play a role in taking the decision on choice of technique for the fixed implant-supported rehabilitation of the severely atrophic maxilla. A high success and survival rate is produced by the majority of fixed implant-assisted prostheses despite the biologic and prosthetic problems. A single approach cannot be recommended as the gold standard. The choice is dependent on the patient's biological factors as well as the clinician's expertise. The included studies were assessed using GRADE criteria. The quality of evidence is low-medium. Therefore, to better comprehend the clinical effectiveness of the treatment alternatives, more well-designed randomized controlled trials with longer follow-up period are required.

Rehabilitation of Acquired Maxillary and Mandibular Defects Secondary to Mucormycosis - A Case Series

Rationale

To suggest a directing algorithm for rehabilitative management of complex soft and hard tissue defects due to mucormycosis.

Patient Concerns

An utmost need for surgical, reconstructive and rehabilitative options; functional, aesthetic, acceptable to the patient and enduring rehabilitation.

Diagnosis

Different cases of rhinomaxillary mucormycosis pertaining to the facial skeleton, diagnosed with the help of radiographic as well as fungal cultures.

Treatment

Thorough medical assessment, and antifungal prescription; followed by surgical resection of the affected areas, rigorous follow-up scheme and later rehabilitation with the help of implants and immediate loading.

Outcomes

Regular follow-ups for at least one year and successful rehabilitation providing acceptable functional outcomes.

Take-away Lessons

Unconventional pathologies like rhinomaxillary mucormycosis infecting the jaws require novel, unprecedented and elaborate procedures both surgical and reconstructive based on sound scientific principles. There must be a vision for the rehabilitation of such cases right from the commencement of the surgical treatment.

Clinical assessment of pterygoid and anterior implants in the atrophic edentulous maxilla: a retrospective study

OBJECTIVES

This study aims to evaluate the short-term clinical outcomes and patient satisfaction of anterior and pterygoid implants in the rehabilitation of edentulous maxilla with posterior atrophy.

METHODS

Given a minimum follow-up of 1 year, 25 patients with fixed maxillary rehabilitation over anterior and pterygoid implants were enrolled in this retrospective study. The implant survival rates, peri-implant soft tissue status (including probing depth, modified sulcus bleeding index, and plaque index), marginal bone loss, and patient satisfaction were measured.

RESULTS

The survival rates for anterior and pterygoid implants at 1-year follow-up were 96.5% and 97.8%, respectively (P>0.05). No statistically significant difference in probing depth, modified sulcus bleeding index, and plaque index was observed between the two types of implants (P>0.05). The marginal bone losses of anterior implants were 0.62 mm± 0.44 mm (mesial) and 0.61 mm± 0.40 mm (distal), and those of pterygoid implants were 0.64 mm± 0.46 mm (mesial) and 0.68 mm± 0.41 mm (distal) mm. These results showed no statistical difference in mesial and distal sites (P>0.05). Patients indicated a high degree of satisfaction with the full-arch prostheses supported by anterior and pterygoid implants.

CONCLUSIONS

For the edentulous maxilla with posterior atrophy, full-arch fixed prostheses supported by anterior and pterygoid implants has an acceptable short-term clinical outcome and excellent patient satisfaction. It may be considered as a predictable and feasible method for maxillary rehabilitation.

Management of Maxillary Cluster Implant Failures with Extra-Maxillary Implants: A Clinical Report

Late cluster implant failures can be one of the most devasting outcomes of implant therapy for patients. It can have anatomic, functional, psychological and financial consequences for patients, and sometimes the loss of residual bone can preclude subsequent implant placement. Fortunately, management of cluster implant failures in the maxilla can be mitigated by using implant anchorage from remote sites like zygomatic and pterygoid regions. Few reports exist in the literature that have described the management of cluster implant failure using extra-maxillary implants such as zygomatic and pterygoid implants. This case report describes the management of a female patient with bruxism who experienced late cluster implant failure in the maxilla after 9 years of function with an overdenture. Due to the loss of residual bone, subsequent implant therapy involved the use of bilateral zygomatic, pterygoid and anterior maxillary implants, which were immediately loaded and thereafter used to support a complete arch fixed implant-supported zirconia prosthesis.

Displacement of a Dental Implant into the Pterygoid Fossa: A Clinical Report

The placement of dental implants in the pterygomaxillary region can be advantageous in maxillary complete arch fixed implant-supported prosthetic rehabilitations to avoid bone grafting and sinus elevation surgeries. Pterygomaxillary implants improve implant biomechanics by eliminating distal cantilevers and increasing the anteroposterior spread with reported mean implant survival rates comparable to traditional implant sites. Although only minor surgical complications have been reported in the literature with the placement of dental implants in the pterygomaxillary region this clinical report describes a major surgical complication involving the displacement of a dental implant into the pterygoid fossa.