Hyaluronic acid-British anti-Lewisite as a safer chelation therapy for the treatment of arthroplasty-related metallosis.

Cobalt-containing alloys are useful for orthopedic applications due to their low volumetric wear rates, corrosion resistance, high mechanical strength, hardness, and fatigue resistance. Unfortunately, these prosthetics release significant levels of cobalt ions, which was only discovered after their widespread implantation into patients requiring hip replacements. These cobalt ions can result in local toxic effects-including peri-implant toxicity, aseptic loosening, and pseudotumor-as well as systemic toxic effects-including neurological, cardiovascular, and endocrine disorders. Failing metal-on-metal (MoM) implants usually necessitate painful, risky, and costly revision surgeries. To treat metallosis arising from failing MoM implants, a synovial fluid-mimicking chelator was designed to remove these metal ions. Hyaluronic acid (HA), the major chemical component of synovial fluid, was functionalized with British anti-Lewisite (BAL) to create a chelator (BAL-HA). BAL-HA effectively binds cobalt and rescues in vitro cell vitality (up to 370% of cells exposed to IC50 levels of cobalt) and enhances the rate of clearance of cobalt in vivo (t1/2 from 48 h to 6 h). A metallosis model was also created to investigate our therapy. Results demonstrate that BAL-HA chelator system is biocompatible and capable of capturing significant amounts of cobalt ions from the hip joint within 30 min, with no risk of kidney failure. This chelation therapy has the potential to mitigate cobalt toxicity from failing MoM implants through noninvasive injections into the joint.

Larger stem to bone diameter ratio predicts lower cemented endoprosthesis failure.

BACKGROUND AND OBJECTIVES: With continued advances in treatment options, patients with endoprosthetic reconstruction are living longer and consequently relying upon their devices for a longer duration. Major causes of endoprosthesis failure include aseptic loosening and mechanical failure. In the setting of tumor resection, loss of bone stock and use of radiation therapy increase the risk for these complications. As such, considerations of remaining native bone and stem length and diameter may be increasingly important. We asked the following questions: (1) What was the overall rate of endoprosthesis failure at a minimum of 5-year follow-up? (2) Does resection length increase implant failure rates? (3) Does implant size and its ratio to cortical width of bone alter implant failure rates? METHODS: We retrospectively analyzed patient outcomes at a single institution between the years of 1999-2022 who underwent cemented endoprosthetic reconstruction at the hip or knee and identified 150 patients. Of these 150, 55 had a follow-up of greater than 5 years and were used for analysis. Radiographs of these patients at time of surgery were assessed and measured for resection length, bone diameter, stem diameter, and remaining bone length. Resection percentage, and stem to bone diameter ratios were then calculated and their relationship to endoprosthesis failure were analyzed. RESULTS: Patients in this cohort had a mean age of 55.8, and mean follow-up of 59.96 months. There were 78 distal femoral replacements (52%), 16 proximal femoral replacements (10.7%), and 56 proximal tibial replacements (37.3%). There were five patients who experienced aseptic loosening and six patients who experienced mechanical failure. Patients with implant failure had a smaller mean stem to bone diameter (36% vs. 44%; p = 0.002). A stem to bone diameter of 40% appeared to be a breaking point between success and failure in this series, with 90% of patients with implant failure having a stem: bone ratio less than 40%. Stem to bone ratio less than 40% increased risk for failure versus stems that were at least 40% the diameter of bone (6/19 [31.6%] vs. 0/36 [0%]; odds ratio 0.68; p < 0.001). Resection length did not appear to have an impact on the rates of aseptic loosening and mechanical failure in this series. CONCLUSIONS: Data from this series suggests a benefit to using stems with a larger diameter when implanting cemented endoprostheses at the hip or knee. Stems which were less than 40% the diameter of bone were substantially more likely to undergo implant failure.

Heterotopic ossification, osteolysis and implant failure following cervical total disc replacement with the M6-C™ artificial disc.

INTRODUCTION: A recent study reported a 34% mid-term revision rate after M6-C™ cervical total disc replacement (CTDR) for wear-related osteolysis. Here, we aim to investigate the prevalence, risk factors, and radiographic characteristics of periprosthetic bony changes and implant failure of the M6-C™ artificial disc. METHODS: We retrospectively analysed radiographic (conventional X-ray, CT scan) and clinical outcomes (EQ-5D-5L, Neck Disability Index (NDI), and Visual Analog Scale (VAS) for neck and arm pain) data collected during routine follow-up of patients who underwent CTDR with the M6-C™ between 2011 and 2015. RESULTS: In total, 85 patients underwent CTDR with the M6-C™. Follow-up data were available for 43 patients (54% female, mean age 44 years) with 50 implants and a mean follow-up of 8.1 years (6.5-11 years). Implant failure with the presence of severe osteolysis was identified in 5 (12%) patients who were all male (p = 0.016) and implanted at the C5/6 level (p = 0.11). All failed implants required revision surgery. The overall prevalence of osteolysis was 44% (22/50 implants) and 34% (17/50 implants) for significant heterotopic ossification. Patients with high-grade osteolysis showed higher VAS arm pain (p = 0.05) and lower EQ-5D-VAS health VAS (p = 0.03). CONCLUSION: We report a lower reoperation rate for failed M6-C™ implants than previously published, but confirmed that osteolysis and heterotopic ossification are common following CTDR with the M6-C™ and may be asymptomatic. Therefore, we strongly recommend ongoing clinical and radiographic monitoring after CTDR with the M6-C™, particularly for male patients implanted at the C5/6 level.

Surgical and audiologic outcomes following revision cochlear implantation in children.

INTRODUCTION: The incidence of cochlear implantation failure is rare; however, complications can arise in which revision surgery becomes necessary. The purpose of this study is to review our institutional experience with revision cochlear implantation to further understand the surgical and audiological outcomes after cochlear implant failure. METHODS: This is a retrospective review of patients who underwent revision cochlear implantation from 2014 to 2022 at a single institution. RESULTS: Twenty-one patients required reimplantation within the 8-year study period. During this time frame, a total of 202 cochlear implants were implanted in 171 pediatric patients, resulting in a reimplantation rate of 5.9 %. Our reimplantation patient population were majority white (61.9 %), female (52.4 %), and insured by Medicaid (61.9 %). The average age at implantation was 54.8 months ±47.5 months and the average age at reimplantation was 100.1 months ±55.9 months. The average time between initial implantation and reimplantation was 46.2 months ±30.2 months. The most common sign of failure was abnormal impedances (47.6 %). Reimplantation was required more often for hard failure (76.2 %), which occurred secondary to trauma in 56.3 % of patients, and occurred more frequently in those ages 5-7. Operative findings were unremarkable in 81 % of patients. Those with audiologic data were noted to have stable or improved thresholds after their revision surgery. Three of the 21 patients discontinued use of their processor on the revised ear. Of these, two had known trauma associated with implant failure that was not immediately addressed. CONCLUSION: We noted increased rates of hard failure, most commonly secondary to trauma. We noted that majority of those who discontinued use of their implant after revision surgery had associated traumatic injuries that ultimately delayed their presentation and surgery.

Mean 23-Year Outcomes of Total Hip Arthroplasty Using a Modular Femoral Stem With Metaphyseal Fixation Sleeve.

BACKGROUND: Although the modular sleeve concept for femoral implants has several advantages, studies reporting on greater than 20-year outcomes are limited. This study aimed to report the mean 23-year results of total hip arthroplasty (THA) using a modular stem with metaphyseal fixation sleeve. METHODS: This study reviewed primary THAs performed using a modular stem between October 1994 and April 1998. Of the 272 hips (221 patients) identified, 220 hips (177 patients) satisfying the minimum 20-year follow-up were included. The Harris Hip Score was used for clinical evaluation. Final hip radiographs were analyzed to evaluate the implant stability and the extent of femoral osteolysis. The mean follow-up duration was 23 years (range, 20 to 28). RESULTS: The mean Harris Hip Score improved from 38 points (range, 26 to 67) preoperatively to 90 points (range, 71 to 100) at the final follow-up (P < .001). Femoral osteolysis was observed in 146 hips (67.1%), but 145 were located proximal to the osseo-integrated sleeve. Overall, 4 femoral revisions were performed; 2 for chronic infection, one for aseptic loosening, and one for periprosthetic femoral fracture. Of the 19 (8.6%) periprosthetic femoral fractures, the most common type was Vancouver AG (13 hips). One (0.5%) asymptomatic distal stem fracture occurred, while no complications were identified at the stem-sleeve junction. Implant survivorship free of any femoral revision was 98.3% at 23 years. CONCLUSIONS: A THA using a modular stem with metaphyseal fixation sleeve demonstrated 98.3% stem survivorship with excellent clinical outcomes at a mean follow-up of 23 years in non-obese patients.

Periprosthetic Fractures: A Rising Tide of Hip Arthroplasty Failure Noted in the American Joint Replacement Registry and the Preventative Role of Cemented Stems.

BACKGROUND: This investigation examined cemented femoral component use in total hip arthroplasty (THA) and its impact on the incidence of periprosthetic fractures (PPFx), a common failure mode in THA. The study leverages data from the American Joint Replacement Registry (AJRR) to assess trends in cemented femoral component usage over time, its association with PPFx rates, and compares the survivorship and 90-day complication rates between cemented and cementless femoral component THAs. METHODS: Primary THAs, captured in the AJRR, in patients aged 65 years and older from 2012 to 2021 were analyzed. Variables considered included age, sex, race, region, teaching status, year, Charlson comorbidity index, and institution bed size. Analysis compared fixation types for THA on all-cause linked revision and PPFx. Logistic regression models analyzed the odds ratios for all-cause linked revision and PPFx for any follow-up time as well as for 90-day revision. The models were adjusted for the listed variables. RESULTS: During the study period, the rate of cement utilization as a percentage of primary THAs performed and reported to the AJRR increased from 4.4 to 8.3%. The rate of THA failure from PPFx increased from 11.4 to 33.3%. When both fixation groups were compared in the univariate analysis, there was a statistically significant difference in all demographic variables (P < .001). To account for this, multivariable logistic regression models were applied. In our models, cemented stems showed a 54.4% (odds ratio: 0.456; 95% confidence interval: 0.347 to 0.599; P < .0001) and 65.8% (odds ratio: 0.342; 95% confidence interval: 0.237 to 0.493; P < .0001) lower risk of PPFx linked and PPFx early linked revision, respectively. CONCLUSIONS: Periprosthetic fractures are becoming a leading failure mode for THAs in the AJRR. Given cemented fixation's relative resistance to this failure mode compared to cementless fixation, we should consider increasing the utilization of this technique.

Ceramic Heads With 12/14 Titanium Sleeves Used on Manufacturer-Non-Compatible Retained Femoral Components Do Not Lead to Implant Failure in Revision Hip Arthroplasty.

BACKGROUND: Ceramic femoral heads with titanium sleeves are commonly used in revision total hip arthroplasty (rTHA). Companies advise against combination with a retained femoral component from another manufacturer. However, no data are available. The aim of this study was to evaluate and compare the implant failure and revision rates of ceramic heads with a 12/14 titanium sleeve used on manufacturer-compatible versus noncompatible retained femoral components. METHODS: A retrospective single-center cohort analysis was performed using a prospectively maintained institutional arthroplasty registry. We identified 439 patients who received a titanium 12/14 ceramic head during rTHA between January 1, 2007, and December 31, 2022. There were 229 manufacturer-compatible and 210 manufacturer-noncompatible retained femoral stems, according to the company's official product compatibility list. Implant failure and rerevision rates were evaluated. RESULTS: After a median follow-up of 6.6 years (IQR (interquartile range): 4.5 to 9.3), there was no significant difference (P = 0.770) in the rerevision rate between the manufacturer-compatible group (17.0%) and the noncompatible group (18.1%). Revision-free survival after rTHA was 81.2% in the manufacturer-compatible group and 78.9% in the manufacturer-noncompatible group after 15 years (P = 0.653). Most rerevisions occurred in the first year after rTHA, with 29 of 229 (12.7%) in the manufacturer-compatible group and 24 of 210 (11.4%) in the manufacturer-noncompatible group (P = 0.705). We observed only one implant failure in the manufacturer-noncompatible group, but this was not related to a mismatch problem. CONCLUSIONS: Although legal uncertainties remain, this study showed no increased risk of implant failure or revision rates when a ceramic femoral head, with a 12/14 titanium sleeve, was used on a noncompatible femoral stem from a manufacturer.

Outcomes of Implant Exchange and Latissimus Dorsi Flap Replacement After Breast Implant Complications.

BACKGROUND: Immediate action is required to address some complications of implant-based reconstruction after mastectomy to prevent reconstruction failure. Implant exchange may be simple but poses the risk of further complications while autologous flap reconstruction seems more complex but may pose less subsequent risk. Which of these is preferable remains unclear. METHODS: We reviewed thirty-two female breast cancer patients who had serious complications with their breast implants after post-mastectomy reconstruction. Latissimus dorsi flap (LDF) patients underwent explantation and immediate reconstruction with an LDF, while implant exchange (IE) patients underwent immediate implant removal and exchange with an expander followed by delayed reconstruction with silicon or immediately with a smaller size silicone implant. RESULTS: LDF patients underwent a single operation with an average duration of care of 31 days compared to an average 1.8 procedures (p= 0.005) with an average duration of care of 129.9 days (p < 0.001) among IE patients. Seven IE (50%) had serious complications that required subsequent revision while no LDF patients required additional procedures. Patient overall satisfaction and esthetics results were also superior in the LDF group at six months. CONCLUSION: In patients who want to reconstructively rescue and salvage their severely infected or exposed breast implant, the LDF offers an entirely autologous solution. LDF reconstruction in this setting allows patients to avoid an extended duration of care, reduces their risk of complications, and preserves the reconstructive process. LEVEL OF EVIDENCE III: The journal asks authors to assign a level of evidence to each article. For a complete description of Evidence-Based Medicine ratings, see the Table of Contents or the online Instructions for Authors at www.springer.com/00266 .

Failure of the linkage mechanism in a semi-constrained total elbow arthroplasty is a rare and unpredictable event: a review of seven cases.

PURPOSE: Linked component of total elbow arthroplasty (TEA) consisted of bushing and locking pins. Failure of linked components is a rare complication of TEA. This study aims to investigate the mechanism and consequence of failure of the linkage mechanism in TEA surgeries. METHODS: Between 2010 and 2021, five patients received revision operation due to linked component failure. Besides, two patients underwent primary operation at another institute were also analyzed due to failure of the linkage mechanism. RESULTS: All seven patients underwent primary TEA and mean age for primary TEA was 48 (range, 27-62). Two patients had TEA for post-traumatic arthritis, three patients for rheumatoid arthritis, and two patients for comminuted distal humerus fracture. The average time between primary TEA and revision TEA for linked component failure was 13.6 years. Three bushing wear and four locking pin dissociation were diagnosed according to pre-operative radiography. Elbow pain and swelling are the most common clinical symptoms. Severe osteolysis, periprosthetic fracture, and stem loosening were noted in three bushing wear cases. In four dissociation of locking pin cases, breakage of male locking pin phalanges was demonstrated in two patients. For revision procedures, both the locking pins and bushings were replaced. No patients in the study required additional surgery after the revision operation for linked component failure. CONCLUSION: Osteolysis, component loosening, periprosthetic fracture may be expected after linked component failure. Patients should be regularly followed up from short-term to long-term with radiography. Early diagnosis and intervention with linked component exchange can prevent extensive revision surgery.

Risk factors for femoral stem fracture following total hip arthroplasty: a systematic review and meta analysis.

BACKGROUND: Femoral stem fracture following total hip arthroplasty (THA) is an infrequent but nevertheless devastating complication, with an increasing worldwide prevalence as demand for primary THA continues to increase. The aim of this study was to perform a systematic review and meta-analysis of risk factors for femoral stem fracture to help identify at risk patients. METHODS: A systematic search was conducted on EMBASE, MEDLINE and AMED to identify relevant studies. Data regarding study design, source, population, intervention, and outcomes was collated. Data extraction was performed on a custom form generated using Cochrane recommended methodology and analysis of risk factors performed including odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: A total of 15 studies reporting a total of 402 stem fractures in 49 723 THAs were identified. The median time from index procedure to stem fracture was 68 months (IQR 42.5-118) whilst mean age at index surgery was 61.8 years (SD 6.9). Male gender (OR = 3.27, 95% CI = 2.59-4.13, p < 0.001), patient weight above 80 kg (OR = 3.55, 95% CI = 2.88-4.37, p < 0.001), age under 63 years (OR = 1.22, 95% CI = 1.01-1.49, p < 0.001), varus stem alignment (OR = 5.77, 95% CI = 3.83-8.7, p < 0.001), use of modular implants (OR = 1.95, 95% CI = 1.56-2.44, p < 0.01) and undergoing revision arthroplasty (OR = 3.33, 95% CI = 2.70-4.1, p < 0.001) were significant risk factors for prosthetic stem fracture. A risk window of 15 years post-surgery was identified. CONCLUSIONS: This review concludes that patient weight, younger age, male sex, varus stem alignment, revision arthroplasty and use of modular stems are significant risk factors for femoral stem fracture. Modifying these risk factors where possible may help reduce incidence of femoral stem fracture in at risk patients.

Is routine antibiotic prophylaxis warranted in dental implant surgery to prevent early implant failure? - a systematic review.

BACKGROUND: The question of whether antibiotic prophylaxis should be administered routinely for dental implant surgery is unresolved. Despite the lack of conclusive supportive evidence, antibiotics are often administered to reduce the risk of infection, which could lead to early implant failure. Increasing antibiotic resistance is a major concern and it is therefore important to reduce the overall use of antibiotics, including in dentistry. The aim of the present systematic review and meta-analysis was to evaluate the efficacy of preoperative antibiotics in preventing early implant failure, in overall healthy patients undergoing dental implant surgery. METHODS: An electronic search was undertaken of PubMed (Medline), Web of Science and the Cochrane Library up to October 1st, 2023, to identify randomized clinical trials (RCTs). All RCTs comparing antibiotic prophylaxis with no antibiotics/placebo in overall healthy patients receiving dental implants were included. The primary outcome was patients with early implant failure. Risk of bias was assessed, data were extracted, a meta-analysis was done, and GRADE certainty-of-evidence ratings were determined. The risk ratio (RR), the risk difference (RD) and 95% confidence intervals (CI) were estimated. RESULTS: After removal of duplicates, 1086 abstracts were screened, and 17 articles were reviewed in full text. Seven RCTs with moderate or low risk of bias and with a total of 1859 patients and 3014 implants were included in the meta-analysis. With reference to early implant failure at patient level, the meta-analysis failed to disclose any statistically significant difference (RR: 0.66, 95% CI: 0.30-1.47) between antibiotic prophylaxis and a placebo. The risk difference was -0.007 (95% CI: -0.035-0.020) leading to a number needed to treat (NNT) of 143. CONCLUSION: Antibiotic prophylaxis for dental implant surgery does not seem to have any substantial effect on early implant failure ( ). The results do not support routine antibiotic prophylaxis for dental implant surgery.

Cluster behavior in dental implant failure - A scoping review.

PURPOSE: To provide an overview of cluster behavior in dental implant failure including the reported prevalence in modern roughened surface implants as well as the risk factors associated with cluster failures. MATERIAL AND METHODS: An electronic search for articles in the English language literature published from January 1, 2000, to March 8, 2023, was performed using PubMed, Embase, Dentistry and Oral Sciences, ProQuest, and Central search engines. Using a standardized systematic search process and predetermined inclusion and exclusion criteria in three stages, the final list of selected articles reporting on cluster behavior in dental implant failure was obtained. Cluster behavior was defined as the failure of two or more implants in the same patient within a 2-year period irrespective of the site. Data from the selected articles were reviewed, critically analyzed, interpreted, and reported. RESULTS: The initial electronic search resulted in 948 titles. After applying inclusion and exclusion criteria, the systematic search process resulted in five clinical studies reporting data on cluster behavior of dental implant failure with modern roughened surfaces. These five studies reported on a total of 9986 implants with 858 reported failures (early and late) over varying periods. Out of the 858 implant failures, 217 implants (25.2%) exhibited cluster behavior. The overall prevalence of cluster behavior of modern roughened surface implant failure was 2.1%.  The most common location risk factors reported were posterior maxilla, history of previous implant failures, poor bone quality, and occlusal overload. CONCLUSIONS: Cluster behavior occurs in 25% of modern roughened surface implant failures which is significantly less than machined surface cluster implant failures. Nevertheless, the overall prevalence of cluster pattern of implant failure of modern roughened surface implants is reasonably low at 2%.

Dental implant failure possibly attributed to embedded pencil graphite: first clinical report.

Implant failures have been associated with a diversity of etiologic processes, predominately arising from bone loss (peri-implantitis) due to inadequate maintenance of oral hygiene or excess luting agents. The aim of this article is to report a novel case of the apparent failure of a dental implant to undergo osseointegration in the presence of submerged pencil graphite. Practitioners are advised to carefully evaluate the clinical and radiographic site of a proposed implant for occult foreign substances. Embedded pencil graphite in the jawbone may promote a foreign body reaction and should be considered in the list of possible contributing factors to dental implant complications.

Conversion to Autologous Breast Reconstruction with Latissimus Dorsi and Immediate Fat Grafting in Patients with Previous Implant Failure: An Efficient, Reproducible, and Safe Technique.

Introduction Implant-based breast reconstructions (IBBRs) increased last years despite the growing indications for radiotherapy in the treatment of breast cancer. As a result, complications and reconstructive failures associated to IBBR have increased. Autologous breast reconstruction (ABR) using fat-augmented latissimus dorsi (FALD) has become popular in recent years. Methods We aimed to evaluate conversion to ABR using latissimus dorsi and immediate fat grafting in 61 cases with IBBR failure. Results Immediate reconstruction was found significatively related with an increased number of surgeries resulting from IBBR complications ( p < 0.001). Note that 41% of the cases presented a grade III/IV Baker and Palmer capsular contracture, 29% implant extrusion, and 21% implant infection. Mean survival of the first implant was 16.95 months. ABR process was completed in 47% of cases with a single surgery. Statistically significant differences were observed between this fact and previous IBBR failure due to infection ( p = 0.03) or extrusion ( p = 0.01). Mean volume of fat graft was 429.61 mL, mean length of the surgical procedure was 3.17 hours, and the average length of hospital stay after surgery was 2.67 days. Only 3.3% of the cases developed some major complication. None of the cases presented reconstructive failure. Conclusion FALD is a very safe total ABR technique, an important fact in patients with previous reconstructive failures. The large volume of fat that can be grafted in a single surgery allows the reconstruction of breast in a reasonable size. The reduced length of surgery and hospital stay make the FALD technique an option to consider when an autologous but efficient and safe reconstruction is desired.

CTAB enabled microwave-hydrothermal assisted mesoporous Zn-doped hydroxyapatite nanorods synthesis using bio-waste Nodipecten nodosus scallop for biomedical implant applications.

In biomedical exploration, the predominant characteristic is synthesizing and fabricating multifunctional nanostructure with intensified biocompatibility and excellent antibacterial applications to avoid post-surgical implant failure. The objective of the current study is to examine ideal mesoporous zinc-doped hydroxyapatite (HAp) for future use in the field of biomedical research. In the present investigation, we synthesized mesoporous Zn-doped HAp nanorods with varied mole concentrations using a profound microwave hydrothermal method utilizing bio-waste Nodipecten nodosus scallop as a calcium source and CTAB as an organic modifier. Bio-waste Nodipecten nodosus scallop is a widely available cheap calcium precursor which is converted into pure and zinc-doped hydroxyapatite nanorods with the help of the microwave hydrothermal method. Different analytical techniques like spectroscopy and electron microscopy were employed to evaluate and precisely characterize the structural and morphological characteristics in synthesized pure and mesoporous Zn-doped HAp nanorods. CTAB and microwave hydrothermal methods successfully create mesoporous Zn-doped hydroxyapatite nanorods with different sizes and morphology. Mesoporous Zinc-doped HAp nanorods show excellent antibacterial activity against Klebsiella pneumoniae (MTCC 7407) and Bacillus subtilis (MTCC 1133), compared to other nanorods. ZnHAp-3 shows notable excellent results of antibacterial effect towards K. pneumoniae and B. subtilis, by exhibiting 12.36 ± 0.12 and 13.12 ± 0.16 mm zone of inhibition. Furthermore, ZnHAp-1 shows the lower zone of inhibition, while the ZnHAp-3 sample shows the highest zone of inhibition. A foremost study performed was toxicity assays to validate safe attributes of mesoporous zinc-doped HAp intensified with the proliferation function of the zebrafish model. The results reveal the non-toxic behavior of pure and mesoporous zinc-doped HAp samples. Thus, our studies provide evidence for the synthesis technique for the mesoporous zinc-doped HAp nanorods using a novel CTAB-enabled microwave hydrothermal method utilizing bio-waste Nodipecten nodosus scallop as a calcium source will be alternative affordable biocidal antibacterial materials for controlling post-surgical implant failures.

Do locking plugs improve implant strength? Biomechanical comparison of polyaxial locking constructs with and without locking plugs in a fracture gap model.

BACKGROUND: The objective of this study was to investigate the effects of locking plugs and the biomechanical properties of a 3.5 mm 8-hole polyaxial locking plate in a fracture gap model. Our hypothesis was that locking plugs would increase the strength and stiffness of the construct. Twelve 3.5 mm 8-hole plates were used to evaluate two different construct designs (with locking plugs vs. without locking plugs) with validated bone substitutes in a 25 mm bridging osteosynthesis gap model. Each construct was subjected to a single cycle four-point bending load to failure using a servo-hydraulic testing machine. Bending stiffness, bending strength, and bending structural stiffness were calculated and compared using an unpaired Student´s t-test. RESULTS: The plating construct with locking plugs did not show any significant increase in terms of bending stiffness, bending strength, and bending structural stiffness compared to plating construct without locking plugs in a 25 mm gap fracture model during a single cycle four-point bending. CONCLUSIONS: Under the conditions tested, filling empty plate holes with locking plugs in bridging osteosynthesis does not increase stiffness or strength of the plate-bone construct.

Implantoplasty and the risk of fracture of narrow implants with advanced bone loss: A laboratory study.

OBJECTIVES: To assess the impact of implantoplasty (IP) on maximum implant failure strength of narrow diameter implants of different type/design and material, with simulated advanced bone loss. MATERIALS AND METHODS: Narrow, parallel-walled implants (3.3 mm in diameter × 10 mm long) with an internal connection of different type/design [bone level (BL), tissue level (TL)] and material [Titanium grade IV (Ti), Titanium-Zirconium alloy (TiZr)] from one specific manufacturer were used. Half of the implants were subjected to IP in their coronal 5 mm; the remaining were used as controls (seven implants per group). Dynamic loading prior to maximum load strength testing was included. RESULTS: During dynamic loading, the fracture rate of BL implants was low and independent of IP, while that of TL implants increased significantly with IP compared with controls (p = .001). Maximum implant failure strength reduction (in %) due to IP, was 1.3%-25.4%; TiZr BL implants were least affected. Implants subjected to IP compared to those without IP as well as TL implants compared to BL implants showed a significantly lower maximum implant failure strength (p < .002); implant material was not significant (p = .845). CONCLUSIONS: Based on data from implants of one specific manufacturer, IP has a significant negative impact on the fracture strength of narrow implants suffering from advanced peri-implantitis. TL implants have been more severely affected compared to BL implants and presented an increased risk for failure during normal chewing forces. In addition, this negative impact of IP on TL implants was independent of the implant material (i.e., Ti or TiZr). CLINICAL RELEVANCE: Narrow single TL implants with advanced horizontal bone loss (e.g., 5 mm), when subjected to IP, appear to have an increased fracture risk during normal function.

Effect of agents affecting bone homeostasis on short- and long-term implant failure.

OBJECTIVES: To review the current evidence on the relationship between agents that affect bone homeostasis and dental implant failures. MATERIALS AND METHODS: Electronic searches for bisphosphonates, denosumab, methotrexate, corticosteroids, romosozumab, sunitinib, and bevacizumab were performed using PubMed, MEDLINE (OVID), EMBASE (OVID), Cochrane Central Register of Controlled Trials (Cochrane Library), Cochrane Oral Health Group Trials Register (Cochrane Library) and Web of Science (Thomson Reuters). Manual searches were also conducted to complement the digital searches for recent issues. RESULTS: Previous publications suggested that bisphosphonates do not compromise the survival of dental implants. However, one study documented an increased risk of implant failure in patients who had received high-dose of intravenous bisphosphonate therapy after implant rehabilitation. There has been an issue of MRONJ around implants in patients who have successfully received implant therapy before and after antiresorptive therapy, leading to late implant failure. Despite evidence on the detrimental effects of denosumab, methotrexate and corticosteroids on bone metabolism, their role in implant survival is not conclusive. CONCLUSIONS: At present, there is insufficient evidence to establish a potential connection between agents that affects bone homeostasis and implant failure. However, some studies have reported negative results for implant therapy. In addition, implant-related sequestration in patients who received anti-resorptive therapy, despite of successful osseointegration, is also noticeable. Although limited studies are available at present, clinicians should still carefully consider the potential hazards and take appropriate precautions to minimize the risks associated with the medications and implant therapy.

Implant failure and associated risk factors of transcrestal sinus floor elevation: A retrospective study.

OBJECTIVES: This retrospective study aimed to evaluate early and late implant loss rates after transcrestal sinus floor elevation (TSFE) and to identify the risk factors related to these failures. MATERIAL AND METHODS: All patients treated with TSFE and simultaneous implant placement during October 2015 to March 2019 were evaluated for inclusion. A total of 802 patients with 976 implants met the inclusion criteria. Clinical and radiographic information was collected from medical records and image software. Univariate and multivariate Cox proportional hazards frailty regression models were performed to identify potential risk factors associated with early and late implant loss after TSFE. RESULTS: The 3-year cumulative implant survival rate was 96.9% (95% CI 95.8%-98.0%). Twelve implants in 12 patients were lost before or at the abutment connection, while 24 implants in 24 patients were lost after functional loading. The Cox frailty regression analyses indicated that two factors were correlated with early implant loss: TSFE with grafting materials, and operators with less clinical experience. As for late implant loss, RBH ≤6 mm, male sex, and certain implant brands were associated with a significantly increased failure rate. CONCLUSIONS: Transcrestal sinus floor elevation with simultaneous implant placement is a predictable treatment option in the atrophic maxilla. The presence of grafting materials and the lack of clinical experience of the surgeon were possibly associated with early implant loss, while low RBH, male sex, and certain implant brands tended to increase late implant loss.

Implant survival in the anterior mandible: A retrospective cohort study.

OBJECTIVE: This study aims to report the implant survival rate of dental implants of partially dentate patients in the anterior mandible and the potential risk indicators for implant failure. MATERIALS AND METHODS: Patients with implant-supported restorations of single or multiple teeth in the anterior mandible restored with fixed partial implant-supported restorations were evaluated. Patient demographic data, implant placement timing, and loading protocol, biological and/or technical complications at the time of the last clinical and radiographic follow-up visit were registered. Survival rate, success rate, and potential risk indicators for implant failure were calculated. RESULTS: A total of 108 patients and 186 implants with a mean follow-up period of 5.48 years (0.1-11.34 years) were included. The 11.3-year cumulative survival rate was 90.9%. Immediate implant placement (OR = 2.75) (p = .08) and immediate implant loading (OR = 8.8) (p = .02*) indicated a higher risk of failure than late implant placement or loading. When combining both categories (type 1A), an OR = 10.59 (p = .04*) for implant failure was found compared to category 4C. Implants placed following static-computer-assisted implant surgery (S-CAIS) showed less risk of failure compared to freehand implant placement (OR = 0.18; 95% CI: 0.02-1.37) (p = .09). CONCLUSIONS: The survival rate of implants placed in the anterior mandible was considerably low (90.9%). S-CAIS, late placement, and conventional loading are protective factor against implant failure in the anterior mandible.