Rehabilitation of the Completely Edentulous Mandible by All-on-Four Treatment Concept: A Retrospective Cohort Study with Up to 10 Years Follow-Up

(1) Background and Objectives. Currently, there are no definitive long-term data about clinically significant difference in the failure of prosthesis and implant or marginal bone loss related to the rehabilitation of the completely edentulous mandible by all-on-four treatment concept. The main aim of present investigation was to report the long-term outcomes (10-years follow-up) of complete-arch mandibular rehabilitations based on the all-on-four concept. (2) Materials and Methods. Patients in need of extractions of teeth due to the occurrence of caries and/or severe periodontal disease and patients presented with edentulous mandibles were enrolled to the study. A total of 96 participants (mean follow-up period after intervention of 3185.2 days) were enrolled in the study. Participants were evaluated at the first visit, 10 days after intervention and every year after the intervention. Implant and prosthesis survival, bone loss and both local biological and mechanical complications were evaluated during the follow-up period. (3) Results. An implants’ survival rate of 97.9% was observed at the end of the follow-up period. Biological complications were reported in 19.8% of patients, whereas mechanical complications were reported in 27.1% of cases. The average marginal bone level at baseline was −0.03 mm. A significant marginal bone loss was observed after 10-years follow-up (2.5 mm). Binary logistic regression analysis showed significant association between smoke and both marginal bone loss and local biological complications. Lastly, a significant association was observed between bruxism and mechanical complications. (4) Conclusions. The high implant and prosthesis survival rate and the moderate incidence of biological and mechanical complications observed in present investigation can be associated to several factors such as high implant primary stability, prosthetic design, and control of the occlusal forces.

Comparison of Outcomes in Obese Patients After Total Knee Arthroplasty With Neutral or Mild Varus: a Retrospective Study With 8-year Follow-up

Background Residual varus after total knee arthroplasty (TKA) can affect functional outcomes and prosthetic survival, which may worsen in the presence of obesity. However, no studies were found to compare the outcomes of obese patients involving postoperative residual mild varus or neutral. The aim of this study was to compare outcomes for knees of obese patients with neutral or mild varus after TKA. Methods We retrospectively reviewed 188 consecutive obese patients (body mass index ≥ 30 kg/m2) at our hospital who underwent TKA due to varus knee osteoarthritis from January 2010 to December 2015. The mechanical hip-knee-ankle axis angle was measured in all patients pre- and postoperatively. Prosthesis survival and knee function were retrospectively assessed based on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Knee Society Knee Score (KS-KS), Knee Society Function Score (KS-FS), Forgotten Joint Score (FJS), and range of motion (ROM). Results Of the 156 knees in 132 obese patients who completed follow-up for a mean of 8.32 ± 1.47 years, 97 knees were corrected from varus to neutral and 54 knees were kept in mild residual varus. Knees with mild varus showed significantly better WOMAC and FJS scores. The two types of knees did not differ significantly in KS-KS, KS-FS or ROM. Although one patient with a neutral knee had to undergo revision surgery, there was no significant difference between two groups.Conclusions For obese patients with osteoarthritis, preservation of residual varus alignment after TKA can improve functional outcomes without compromising prosthesis survival.

Surgical and Prosthetic Outcomes of 967 Implants Under Immediate or Delayed Loading in Full-Arch Rehabilitation: a Retrospective Study With up To 5 Years of Follow-Up

Objective: The aim of this study was to evaluate implant and prosthesis survival rates in full-arch rehabilitation supported by implants with platform-switched Morse taper connection submitted to immediate or delayed loading, after up to 5 years of follow-up. Material and Methods: Data was retrospectively collected from clinical records of patients who were treated by means of implant-supported full-arch rehabilitation. Survival rates of implants and prostheses were evaluated according to immediate or delayed loading. Results: The sample comprised 967 implants. Of those, 627 were submitted to immediate loading (IL) while 340 to delayed loading (DL). After a follow-up period of up to 5 years, the implant survival rate for IL was of 99.7% (622/627 implants) and 97.2% (333/340 implants) for DL. The overall implant survival rate was 98.8% (955/967 implants). Prosthesis survival rate was 100% (N = 178) for both groups. Significantly more implants in the DL group presented bone loss (p > 0.01), either greater or lower than 2 mm, during the follow-up period. Conclusion: Within their limits, the present results suggest that full-arch rehabilitation with platform-switched Morse taper connection implants can lead to surgical and prosthetic predictable outcomes. Moreover, immediate loading protocol seems to be a good option for the rehabilitation of fully edentulous patients, as it involves a shorter treatment time, which may lead to greater patient satisfaction. Keywords Dental implants; Rehabilitation; Survival rate; Retrospective study.

Complications, Reasons for Reoperation, and 5-Year Prosthesis Survival Compared Between the Cemented and Cementless Oxford Unicompartmental Knee Arthroplasty Fixation Techniques at Thailand’s Largest National Tertiary Referral Center

Background: Oxford unicompartmental knee arthroplasty (OUKA) yields favorable outcomes in patients with medial compartmental knee osteoarthritis; however, it remains unknown whether cemented or cementless OUKA fixation delivers better outcomes in Asian population. Accordingly, this study aimed to investigate the complications, reasons for reoperation, and 5-year prosthesis survival compared between cemented and cementless OUKA in Thai patients.Methods: A total of 466 cemented and 36 cementless OUKA that were performed during 2011-2015 with a minimum follow-up of five years were included. With reoperation for any reason as the endpoint, Kaplan-Meier analysis was performed to compare 5-year implant survival between groups. Complications, reasons for reoperation, and 90-day morbidity and mortality were compared between groups. Cox proportional hazards model was used to identify independent predictors of implant survival.Results: There was no significant difference in 5-year implant survival between the cemented and cementless groups (96.4% vs. 94.4%, p=0.375). The mean implant survival time was 113.0±0.8 and 70.8±1.9 months in the cemented and cementless groups, respectively (p=0.383). The most common reason for reoperation was bearing dislocation, and only one patient had 90-day morbidity. There was no significant difference between groups for complications or reasons for reoperation. No independent predictors of implant survival were identified in multivariate analysis.Conclusions: OUKA was shown to be a safe and durable reconstructive procedure in Thai patients with medial compartmental knee osteoarthritis. There was no significant difference in implant survival between the cemented and cementless groups during the 5-year follow-up, and no independent predictors of implant survival were identified. Trial registration: Thai Clinical Trials Registry, TCTR20200427004. Registered 27 April 2020 – Retrospectively registered.

Chondrocalcinosis does not affect functional outcome and prosthesis survival in patients after total or unicompartmental knee arthroplasty: a systematic review

Purpose There are contentious data about the role calcium pyrophosphate (CPP) crystals and chondrocalcinosis (CC) play in the progression of osteoarthritis (OA), as well as in the outcomes after knee arthroplasty. Hence, the purpose of this systematic review was to analyse the clinical and functional outcome, progression of OA and prosthesis survivorship after unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) in patients with CC compared to patients without CC. Methods A systematic review of the literature in PubMed, Medline, Embase and Web of Science was performed using the “Preferred Reporting Items for Systematic Reviews and Meta-Analysis” (PRISMA) guidelines. Articles which reported the outcome and survival rates of prosthesis after TKA or UKA in patients with CC were included. Results A total of 3718 patient knees were included in eight selected publications, with a median sample sizes of 234 knees (range 78–1000) and 954 knees (range 408–1500) for publications including UKA and TKA, respectively. At time of surgery, the mean age was 69 years and the prevalence for CC ranged from 12.6 to 36%. Chondrocalcinosis did not significantly influence the functional and clinical outcome, the implant survival as well as the radiologic progression of OA disease after UKA and TKA. Conclusion The presence of CPP crystals in tissue samples, synovial fluid or evidence of calcifications on preoperative radiographs did not significantly influence the postoperative functional and activity scores. It also had no significant influence on prosthesis survival rate, whether it was a UKA or a TKA. This study shows that the impact of a subclinical form of chondrocalcinosis may not be of clinical relevance in the context of arthroplasty. Level of evidence IV.

Does the type of surgical approach affect the clinical outcome of total knee arthroplasty?

Background The aim of the study was to investigate the issue of medial midvastus (MMV) vs. medial parapatellar (MPP) approaches in total knee arthroplasty (TKA). It was hypothesized that the two surgical approaches would produce significantly different results with respect to patient-reported knee score outcome (hypothesis 1), short-term postoperative range of motion (ROM) (hypothesis 2), long-term postoperative ROM (hypothesis 3) and prosthesis survival (hypothesis 4). Methods A retrospective comparative study design was applied. Data sets were obtained from the state arthroplasty registry. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC) data were analyzed from preoperative and 1 year postoperatively. The ROM data were analyzed for the time points preoperative, postoperative days 4 and 10 and 1 year. Results Available were 627 cases (407 MMV vs. 220 MPP) and 1 year postoperatively there were no significant differences between groups regarding the WOMAC scores (hypothesis 1). Early postoperatively on days 4 and 10 after TKA there were no differences between groups (p = 0.305 and p = 0.383, respectively, hypothesis 2). Likewise, ROM did not significantly differ between the groups 1 year after TKA (p = 0.338, hypothesis 3). The 5‑year prosthesis survival did not differ between the groups and showed 94.46% (95% confidence interval, CI 90.69–96.73%) in the MMV group and 94.33% (95% CI 89.96–96.83%) in the MPP group (p = 0.664, hypothesis 4). Conclusion Both surgical approaches produce equivalent clinical results in terms of early postoperative ROM, late postoperative ROM and 1‑year WOMAC. The same prosthesis survival rates can be expected.