Prosthetic Complications Research Articles

Can Reinforcement of Maxillary Implant Overdentures Decrease Stress on Underlying Implants?

Reinforcement of maxillary implant overdentures is necessary not only for preventing prosthetic complications but also for protecting underlying structures, as it makes the denture base more rigid. However, few studies have investigated the effects of reinforcement on the underlying structure. The purpose of this study was to examine the effects of reinforcement on implant stress under various implant configurations and denture designs. A maxillary edentulous model with implants and experimental overdentures with and without palatal coverage and three types of cast reinforcement was fabricated. Four strain gauges were attached to the implants in the anterior, premolar, and molar areas. A vertical occlusal load of 98 N was applied through the mandibular complete denture, and the strain on the implants was compared using one-way analysis of variance (P = .05). In dentures with palatal coverage, reinforcement significantly decreased the strain on the anterior and molar implants. In palateless dentures, reinforcement with a palatal bar decreased the strain most on the anterior and molar implants. Reinforcement of maxillary implant overdentures decreased the strain on underlying implants, regardless of the denture design and implant configurations.

Rehabilitation of the Atrophic Posterior Maxilla Using Splinted Short Implants or Sinus Augmentation with Standard-Length Implants: A Retrospective Cohort Study.

To retrospectively compare short implants (6 to 8 mm) (short group) to standard-length implants (≥ 11 mm) inserted in combination with a lateral sinus elevation procedure (sinus group), supporting partial fixed prostheses in the atrophic posterior maxilla. Records of 118 patients treated with fluoride-modified implants in the atrophic posterior maxilla between January 2009 and December 2011 were screened in two private practices. Two to four implants were placed in each patient and loaded after 5 to 6 months with partial fixed prostheses. Patients were followed for at least 3 years after implant placement. Patients were contacted and invited for clinical and radiologic follow-up examinations. Outcome measures were implant failures, complications, soft tissue parameters, and marginal bone levels. Fisher exact and unpaired t tests were used to compare proportions and means at the .05 level of significance. A total of 101 patients attended the examination: 53 (112 implants) in the sinus group and 48 (109 implants) in the short group. The mean observation period was 47.03 ± 7.46 months for the sinus group and 44.18 ± 6.42 months for the short group. Ten surgical complications occurred in nine patients of the sinus group versus only one complication in the short group; the difference was statistically significant (P = .01). Six implants failed in five patients of the sinus group versus two implants in two patients of the short group. At follow-up, mean marginal bone loss was 0.64 ± 0.58 mm in the sinus group vs 0.48 ± 0.5 mm in the short group. No significant difference was observed in terms of implant failures, prosthetic complications, soft tissue parameters, or marginal bone loss between the two groups. Within the limitations of this study, both techniques showed similar medium-term outcomes, but short implants provided advantages in terms of a reduced number of surgical complications.

Retrospective 2- to 7-Year Follow-Up Study of 20 Double Full-Arch Implant-Supported Monolithic Zirconia Fixed Prostheses: Measurements and Recommendations for Optimal Design.

To measure the extension of cantilever lengths, thicknesses, and heights of zirconia prostheses in the lingual and facial areas of the distal screw access openings, and to evaluate the clinical performance regarding chipping or fracture of the distal cantilevered sections of double full-arch CAD/CAM screw-retained, stained, monolithic zirconia, gingival-colored ceramic implant-supported fixed prostheses (MZ-FPs). Ten edentulous patients were provided with a total of 20 CAD/CAM double full-arch MZ-FPs. The zirconia thicknesses around distal screw access openings at three different levels (crown height space, screw access opening lengths, and dimensions of the cantilevered segments) were measured in the resin prototypes. Patients were evaluated clinically (visually) without magnification, with intraoral digital photography, and radiologically by the author, approximately every 6 months. Ten patients with 20 MZ-FPs were evaluated. Twenty resin prototypes with 35 cantilevered segments (15 maxillary, 20 mandibular) were measured. The lingual and facial thicknesses of the resin frameworks and the crown height spaces of 35 distal access openings were measured. The average extension of the maxillary cantilever segments was 7.72 mm; the mandibular cantilever average was 13.72 mm. The average crown height space for maxillary prostheses was 13.27 mm, for the mandibular prostheses it was 11.89 mm. Zirconia thickness around distal screw access openings at the middle of the crowns, margins and middle of the gingival areas (buccal side of maxillary prostheses) was 4.29, 3.79, and 3.87 mm, respectively. On the lingual sides the thicknesses were 3.13, 2.85, and 3.15 mm, respectively. For mandibular prostheses the thicknesses were 3.56, 3.08, and 3.15 mm, respectively, on the buccal sides, and 2.07, 2.00, and 2.99 mm, respectively, on the lingual sides. No implant failure or changes in the occlusal surface, chipping of the cuspid or incisal edges, or prosthesis distal extension fractures were observed during follow-up periods ranging from 2 to 7 years. The survival rate was 100% for implants and prostheses. In one of the patients, chipping of the pink ceramic was noted in the maxillary prosthesis 36 months after placement. The results of this study indicated that full-arch MZ-FPs without cutback, or with partial digital cutback and veneering ceramic, were a therapeutic option. Recommendations regarding the thickness of zirconia at the level of the distal screw access openings, the crown height spaces, and the lengths of the cantilever segments were recorded. Additional in vitro and clinical studies will be required for more scientific analysis of the criteria for design of this type of prosthesis to minimize prosthetic complications. Long-term and multicenter studies are needed to corroborate the findings discussed in this report.

Complications of endodontically treated teeth restored with fiber posts and single crowns or fixed dental prostheses-a systematic review.

The present systematic review aimed at assessing data from the literature on endodontic and prosthetic complications in endodontically treated teeth restored with fiber posts and single crowns (SCs) or fixed dental prostheses (FDPs). Available randomized controlled clinical trials evaluating endodontic and prosthetic complications in the teeth treated with fiber posts and restored with different prosthetic restorations were reviewed. PubMed, Evidence-Based Dentistry, BMJ Clinical Evidence, Embase, DynaMed, and gray literature restricted to scientific literature were analyzed; also, manual researches were performed. English language and time filters (from 1990 to 2015) were used. The database search produced 4230 records, many of which were duplicates. The manual research did not produce any other relevant article. After duplications were removed, all the selected databases produced 3670 records. Reading titles and abstracts, two independent reviewers excluded 3664 reports. The full-texts of the remaining six reports were read. Only four studies met the inclusion criteria and were included in this systematic review. The most frequently reported failures in the available studies were as follows: fiber post debonding, loss of retention of single crowns, and marginal gaps. Less frequently, chippings and fractures were recorded in SCs. No studies about complications related to FDPs were found. A correlation between the failure rates of fiber posts and the type of prosthetic restorations just like SCs and FDPs cannot be found to date. Further randomized controlled clinical studies are required to achieve evidence-based conclusions, particularly about the use of fiber posts with FDPs.

Is Alveolar Ridge Split a Risk Factor for Implant Survival?

There is a paucity of studies that have assessed the long-term outcomes of the alveolar ridge split (ARS). This study evaluated the intraoperative and postoperative complications and assessed the placed dental implant and prosthesis. A retrospective study of the ARS was conducted in a single private dental clinic. The predictor variable was the ARS technique (1 stage vs 2 stages). The primary outcome was the dental implant survival rate. Secondary outcomes were intraoperative complications, marginal bone loss, prosthetic complications, and prosthesis success rate. Descriptive analysis was performed for patients' demographic data, implant details, and prosthetic complications. The Kaplan-Meier method was used to assess implant survival rate and prosthesis success rate. Twenty patients (mean age, 55 ± 6yr) had a mean follow-up time of 5years. Delayed implant placement was performed when the residual alveolar bone width was narrower than 3mm. No intraoperative or postoperative complications were reported. The survival rate of the 31 implants was 100% and the prosthesis success rate was 96.8%. The ARS is an effective technique for horizontal bone augmentation in the mandible. Delayed dental implant placement when the alveolar bone width is narrower than 3mm could minimize the risk of buccal wall fracture.

The all-on-four concept may be a viable treatment option for edentulous rehabilitation.

Data sourcesMedline, the Cochrane Library, Google and hand-searches of systematic reviews and bibliographies from related journals in English and German up to August 2012.Study selectionThree reviewers independently searched for clinical trials that assessed the success rates of placing two anterior and two posterior tilted dental implants in humans either in the maxilla or mandible according to the all-on-four treatment concept. Inclusion limited studies with a minimum follow-up period of one year.Data extraction and synthesisThe primary outcome measure was the failure rate of implants. The secondary outcomes were prosthesis failure and marginal bone loss/bone level changes assessed through radiological examination. Failure rate was used to calculate standard deviations (SDs) of implants, whereas the mean success rate was used for dental implants and prostheses. Evaluation and quality assessment of articles and data extraction were performed by three independent reviewers. These reviewers estimated risk of bias by assessing the trial quality using a criteria form focused on the trial design, specification of inclusion/exclusion criteria, performance of surgery, outcome measure provided, radiographic examination of marginal bone level change as well as its evaluation and completeness of follow-up. Outcome measures were based on weighted means using a variance components analysis.ResultsThirteen studies, including 4,804 dental implants (2,000 maxilla and 2,804 mandible) placed in 1,201 jaws met the inclusion criteria. Nine were prospective trials, three retrospective studies and one longitudinal trial. All studies except one were considered to be at high risk of bias. Seventy-four (37 axially, 37 tilted) dental implants failed, with most failures (74%) within the first 12 months. Fifty-seven out of 1,201 prostheses failed but were repairable. The major prosthetic complication was the fracture of the all-acrylic prostheses. At 36 months the mean cumulative survival rates for implants and prostheses were 99.0 ± 1.0% (SD) and 99.9 ± 0.3% (SD), respectively with an average bone loss of 1.3 ± 0.4 mm (SD). There were no statistically significant differences in the clinical outcomes between maxillary versus mandibular arches and axially versus tilted placed implants.ConclusionsThe available evidence shows a promising short-term prognosis for the all-on-four treatment concept. However the evidence is limited by the quality of the available studies and the paucity of clinical trials of greater than five years.

Impact of Crown-Implant Ratio of Single Restorations Supported by 6-mm Implants: A Short-Term Case Series Study.

High crown-implant ratios might affect the biologic and technical performance of a reconstruction. The aim of this study was to assess whether a higher crown-implant ratio of single restorations on 6-mm implants resulted in more peri-implant bone loss and more prosthetic complications during a 1-year followup period. A group of 37 patients were provided with 47 single-implant-supported restorations on 6-mm implants. Implants were placed in the posterior mandible or maxilla, where limited bone height was available. The clinical crown-implant ratio was determined on digitized casts. Peri-implant bone changes were analyzed on intraoral radiographs. Prosthetic complications were scored throughout the evaluation period. The mean crown-implant ratio was 2.14 ± 0.42. The mean peri-implant bone loss was 0.13 ± 0.36 mm. No complications occurred. High crown-implant ratios are not accompanied by increased peri-implant bone changes or prosthetic complications during a 1-year follow-up period.

The Effect of Crown-to-Implant Ratio on the Clinical Performance of Extra-Short Locking-Taper Implants.

The aim of the present prospective 5-year study was to evaluate the influence of crown-to-implant ratio (C/I ratio) on the survival, peri-implant marginal bone loss, and complications of extra-short (6.5 mm) locking-taper implants placed in the posterior areas of the jaw. Over a 2-year period, all patients presenting with partial edentulism associated with vertical defects of the posterior alveolar ridges and sufficient bone volume to place extra-short (6.5 mm length × 5 mm diameter) implants were considered for inclusion in this study. Fifty-one patients (22 men, 29 women; aged between 40 and 75 years) were included in this study. Sixty-eight extra-short, locking-taper implants were placed to support 49 single crowns and 9 fixed partial dentures. The C/I ratio was <2 for 51 implants and ≥2 for 17 implants. All patients underwent the 5-year clinical examination. Two implants failed. Failure proportion was 2% in the C/I<2 group, and 6% in the C/I≥2 group: this difference was not statistically significant (P = 0.4). After 1 year of loading, a mean marginal bone loss of 0.29 and 0.39 was reported in the C/I<2 group and the C/I≥2 group, respectively. After 5 years of loading, a mean marginal bone loss of 0.38 and 0.48 was reported in the C/I<2 and C/I≥2 groups, respectively. The linear regression model failed to find a correlation between the C/I ratio and marginal bone loss along time, with a 0.023 mm (95% CI: -0.002; 0.048) increase in 1-year bone resorption for every 0.1 increase in C/I ratio (P = 0.07). At 5-year, the association reduced to 0.019 mm (P = 0.18). Only a few complications were reported. There was no statistically significant difference in the prevalence of biological (P = 0.9) complications between the 2 groups. Prosthetic complications were more frequent with C/I≥2 (12.5%) than with C/I<2 (6%), but this difference was not statistically significant (P = 0.6). Extra-short, locking-taper implants may be successfully used in the posterior areas of the jaw.

Clinical Evaluation of 762 Single-Tooth, Locking-Taper Implants: A Prospective Study with 1- to 12-Years of Follow-Up

Results: 762 implants were placed in 654 patients (324 males, 330 females; aged between 21–80 years, mean age 52.7 ± 14.4 years). Eighteen implants (11 maxilla, 7 mandible) failed, giving an overall cumulative implant survival rate of 96.9% (patient-based) and 97.3% (implant-based) at 12-year follow-up. Among the surviving 744 implants, 45 biological complications (6.0%) and 26 prosthetic complications (3.4%) were reported, giving a 12-year cumulative “complication-free” survival of restorations of 72.7%. A mean MBL of 0.34 (± 0.27 mm), 0.46 (± 0.29 mm) and 0.83 (± 0.41 mm) was observed, respectively at the 1-, 6- and 12-year follow-up examinations. Conclusions: Locking-taper implants represent a good treatment option for the rehabilitation of single-tooth gaps in the long-term, with high survival rates and low incidence of complications.

Clinical and radiographic evaluation of implants placed by means of inferior alveolar nerve lateralization: a 5-year follow-up study.

To evaluate clinical and radiological responses of implants placed in combination with inferior alveolar nerve lateralization, analyzing survival and success rates over 5years functional loading. This prospective, longitudinal, single-center study recruited 40 patients with mandibular atrophy in the posterior sectors, who underwent lateralization of the inferior alveolar nerve. Three months after surgery and implant placement, the implants were loaded by means of screw-retained implant-supported partial prostheses or fixed complete prostheses. Clinical and radiographic examinations were performed immediately after implant placement and at 12, 24, 36, 48 and 60-month follow-up visits. The 40 patients received a total of 129 implants (Phibo TSA™ , Phibo Dental Solutions, Sentmenat, Barcelona, Spain). Two implants were lost in the first month after surgery, generating an implant cumulative survival rate (CSR) of 98.44%. The success rate after 5years of loading was 98.44%. No intra-operative or postoperative soft tissue or prosthetic complications occurred during the 5-year follow-up. Inferior alveolar nerve lateralization performed to allow placement of (Phibo TSA™ ) implants in patients with mandibular atrophy obtained predictable clinical and radiological results over five years of functional loading.

Implant Abutment Cleaning by Plasma of Argon: 5-Year Follow-Up of a Randomized Controlled Trial.

Contamination of implant abutments could potentially influence the peri-implant tissue inflammatory response. The aim of the present study is to assess the radiographic bone changes around customized, platform-switched abutments placed according to the "one-abutment-one-time" protocol, with and without plasma of argon cleaning treatment. Thirty healthy patients with thin gingival biotype (<1 mm) and history of periodontal disease received one maxillary implant each. Immediately before abutment connection, patients were randomly assigned to control group (cleaning protocol by steaming) or test group (plasma of argon treatment). Outcome measures were: 1) success rate of implants and prostheses; 2) biologic and prosthetic complications; 3) peri-implant marginal bone loss (MBL); 4) esthetic and periodontal parameters; and 5) patient satisfaction. Neither implants nor prostheses were lost in either group at the 5-year follow-up examination. Overall, both groups showed a slight amount of peri-implant bone loss from baseline to 5 years. A statistically higher mean MBL was found in the control group compared with the test group at 6, 24, and 60 months after crown connection. Nevertheless, during the entire follow-up period, intragroup comparison demonstrated statistically significant mean MBL in the control group, but not in the test group. The test group showed a higher mean gain at the soft tissue margin, but not for the papilla. All implants showed good periodontal parameters, with no significant differences between groups. Plasma of argon could be used to disinfect implant abutments before insertion to minimize future peri-implant bone resorption.

A retrospective multicenter case series evaluating a novel 3.0-mm expanding tapered body implant for the rehabilitation of missing incisors.

Narrow-diameter implants are indicated for narrow sites, small interdental/interimplant spaces, or sites with congenitally missing teeth. They also offer a substitute for invasive augmentation procedures. The authors retrospectively evaluated the performance of a new 3.0-mm diameter implant for rehabilitating small anterior spaces. This observational multicenter retrospective case series included consecutive patients needing single-unit restoration for mandibular and lateral maxillary incisors. The outcome variables were: implant survival, Plaque Index, pocket probing depth (PPD), Jemt's papilla index, bleeding on probing (BOP), and marginal bone remodeling. In total, 45 patients received 58 3.0-mm implants placed in healed sites (n = 22), extraction sockets (n = 16), or sites with congenitally missing teeth (n = 20). Average follow-up time was 15.1 ± 5.2 months. Prosthetic loading was immediate (n = 23), early (n = 16), or delayed (n = 19). Two implants were lost, and two prosthetic complications occurred. One-year bone remodeling averaged -0.36 ± 0.85 mm (n = 44). PPD averaged 1.75 ± 0.58 mm. Neither BOP nor plaque was detected around implants. At 1-year follow-up, narrow 3.0-mm diameter implants placed in mandibular and lateral maxillary incisor sites demonstrate a high survival rate and support stable marginal bone levels and healthy soft tissue.

Radiological and Biological Assessment of Immediately Restored Anterior Maxillary Implants Combined with GBR and Free Connective Tissue Graft.

Radiologic and biologic assessment of immediately restored Implants combined with guided bone regeneration (GBR) and free connective tissue graft. 1-4 year retrospective study involving 34 patients treated with maxillary immediately restored anterior single-implants. Soft tissue dimensions, radiographic bone loss, and biological and prosthetic complications were assessed. During the mean follow up period of 29 months the study group presented a mean mesial bone loss of 1.10 ± 0.39 mm (range: 0.5-2.4 mm), and mean distal bone loss of 1.19 ± 0.41 mm (range: 0.4-2.1 mm). Mean periimplant probing depth of 3.49 mm (SD ± 1.06) and 2.35 (SD ± 0.52) for the contralateral tooth (highly significant p < 0.001). Bleeding on probing was present in 29.4% of the examined implant supported crown sites and 10.4% of the contralateral teeth (p < 0.001). Anterior maxillary single-tooth replacement, using GBR and connective tissue graft according to the concept of immediate implant placement, and non-functional restoration is an accepted treatment modality achieving favorable peri-implant soft tissue condition.

Application of Ce-TZP/Al2O3 nanocomposite to the framework of an implant-fixed complete dental prosthesis and a complete denture

PatientA 69-year-old Japanese male visited Nihon University Dental Hospital for refabrication of his mandibular implant-supported complete fixed prosthesis (ISCFPD) and maxillary complete denture, which had been fabricated 15 years previously. In this case, Ce-TZP/Al2O3 nanocomposite (Ce-TZP/A) was applied to the framework of the mandibular ISCFPD and maxillary complete denture. Three years after deliver of the framework, no particularly notable biological or prosthetic complications were observed, and a high level of patient satisfaction had been achieved. DiscussionConventional ISCFPD frameworks were fabricated by casting gold alloys; however, with the recent advancement of CAD/CAM technology, titanium (Ti) or yttria tetragonal zirconia polycrystal (Y-TZP) frameworks have become more common. In contrast, the main fabrication method for Ti or Co-Cr frameworks of removable dental prostheses has shifted from the conventional casting method to CAD/CAM fabrication. Ce-TZP/A, which was chosen as the framework material this time, shows higher strength and greater toughness than Y-TZP. However, since it has a low light-transmitting property and exhibits an opaque white color, the range of its application in fixed prostheses, particularly in the esthetic area, is limited. ConclusionWe described a case in which Ce-TZP/A was applied to the frameworks of a mandibular ISCFPD and a maxillary complete denture. No particularly notable biological or prosthetic complications were observed in the mandibular ISCFPD or the maxillary complete denture, and a high level of patient satisfaction was achieved. Medium- and long-term observations with a greater number of cases are essential to obtain information concerning various phenomena related to this procedure.

Long-term success of dental implant-supported dentures in postirradiated patients treated for neoplasms of the maxillofacial skeleton: a retrospective study.

The reconstruction of oral function in irradiated patients with craniofacial tumors is a significant challenge. The aim of this study was to detect long-term success of dental implant-supported dentures in postirradiated patients treated for neoplasms of the maxillofacial skeleton. From 2004 to 2011, 36 irradiated patients underwent oral function reconstruction using implant-supported prostheses. Bone augmentation was completed using vascularized bone grafts in 22 patients. Fourteen patients were treated by hyperbaric oxygen therapy (HBO). A total of 198 dental implants were used in jaw rehabilitation. After loading, implant success rates, biological and prosthetic complications, patient satisfaction, and psychological changes were recorded. Bone augmentation of the jaw was successful and vascularized grafts provided an additional vascular supply in compromised irradiated tissue. Rehabilitation was successful in all of the patients after loading. Thirty-eight dental implants failed, and 35 implants were removed. The success rate of the implants was 93.6% for 10years after loading. It was not a significant difference in implant success rate between the HBO group and the other groups. The prosthodontic maintenance results and complication rates showed that patients required intervention 0.19 times per year. All patients were satisfied with the oral restoration results. The restoration of oral function in radiotherapy patients with tumor resection using implant-supported prostheses is a viable treatment option. Either alone or in combination with HBO, dental implant-supported prostheses can be used an effective therapeutic approach for irradiated patients with oral function reconstruction.

No Clear Evidence of the Effect of Cantilevered Implant Supported Fixed Restorations on the Marginal Bone or the Prosthetic Complications

Effect of cantilevers for implant-supported prostheses on marginal bone loss andprosthetic complications: systematic review and meta-analysis. Torrecillas-Martinez L, Monje A, Lin G, Suarez F, Ortega-Oller I, Galindo-MorenoP, Wang H. Int J Oral Maxillofac Implants 2014;29(6):1315-21. Not reported Systematic review and meta-analysis.

Mini dental implants retaining mandibular overdentures: A dental practice-based retrospective analysis

PurposeThe purpose of this study was to assess the survival of mini dental implants (MDI) and to measure prosthetic maintenance needs in a dental practice-based setting. MethodsPatients with mandibular removable dentures were provided with MDI to improve denture retention. Complications and maintenance were analyzed by use of patient records and evaluated with Kaplan–Meier curves and the log rank test at a significance level of 0.05. ResultsNinety-nine MDI were placed in 25 patients (mean age: 72 years). Two MDI fractured during placement and eight implants failed during the first weeks. No more implants were lost for up to seven years, resulting in 92% survival. Implant survival differed significantly depending on whether the maxilla was provided with complete dentures (94.9%) or with partial dentures (81%). All prostheses were in use at the time of data extraction. Denture base fractures were observed in six cases, an incidence of fractures of 24%. Some minor intervention was necessary: one resin tooth fractured, retention rings were changed in five cases, and repeated relining was required for 16% of the dentures. ConclusionsAfter mid-term observation, survival of MDI was good. However, the incidence of denture base fractures and of minor prosthetic complications should not be under-estimated.

The clinical prognosis of implants that are placed against super-erupted opposing dentition.

ObjectivesIf teeth are missing, super-eruption of teeth in the opposing arch can occur in the area and can change the occlusal plane. When missing teeth are replaced with implants, the oral surgeon must determine whether or not the super-erupted teeth need to be treated in order to normalize the occlusal plane. In this study, we evaluated the clinical prognosis of dentition after implant placement and prosthetic treatment were completed in an occlusal plane altered by super-erupted teeth in the opposing arch without additional treatment of the super-erupted teeth.Materials and MethodsTwenty-two patients (9 males, 13 females) were treated with implants and prosthetics without addressing the super-erupted opposing dentition from April 2004 to August 2012 at Seoul National University Bundang Hospital. A total of 33 implants were placed. Values of crestal bone loss, survival rates, and surgical and prosthetic complications for an average of 29.6 months after prosthetic loading were recorded.ResultsIn one case, the cover screw was exposed after implant surgery. The mean crestal bone loss was 0.09±0.30 mm. Of the 33 implants, 31 survived, a survival rate of 93.94%. A prosthetic complication occurred in one case but functioned well after correction.ConclusionFavorable clinical results from prosthetic complications, crestal bone loss, and implant survival rates were exhibited in implants next to a super-erupted opposing tooth.

THE ROLE OF ANTICOAGULATION THERAPY IN PATIENTS WITH PROSTHETIC HEART VALVES

Cardiac surgery is the only radical method of treatment of valvular defects (congenital or acquired): valve preservation procedures or prosthetics operations. 250 000 – 280 000 valve prostheses are implanted every year worldwide, while the number of prosthetic valves operation increases by an average of 5–7 % per year (biological prostheses – 8–11 %, mechanical prostheses – 3–5 %). Selection of biological or mechanical types of prosthesis, its location, the presence of associated risk factors for embolic events, such as atrial fibrillation, previous embolism, left ventricular dysfunction, hypercoagulable states determine patient management tactics. Particularly high risk of prosthetic thrombosis and thromboembolic complications can be seen in case of mechanical prosthesis implantation. Numerous prospective and retrospective clinical studies have proven high effectiveness of anticoagulants for reduction the risk of cardioembolic complications. The degree of anticoagulation (optimal international normalized ratio (INR)) is determined by risk factors for prosthetic thrombosis and thromboembolic complications in a patient, as well as thrombogenicity of the prosthesis by itself; INR may range from 2.5 to 4.0. International recommendations take into account the presence/absence of additional risk factors for thromboembolism, and based on warfarin administration with the achievement of target INR values combined with low-dose aspirin. Administration of novel direct oral anticoagulation remedies in patients with prosthetic heart valves has not been studied sufficiently up to date and is contraindicated. Thus, warfarin currently is a drug of choice for the prevention of thromboembolic complications in patients with prosthetic heart valves.

Reoperation Rates for Penile Prosthetic Surgery.

In patients with erectile dysfunction refractory to medical treatment, placement of a penile prosthesis is an effective treatment option. Despite advancements in prosthetic design, it is not without complications requiring reoperation. To evaluate the long-term reoperation rate of penile prosthesis implantation. A longitudinal analysis of the California Office of Statewide Health Planning and Development database from 1995 to 2010 was performed. Inclusion criteria were men who underwent their first penile prosthetic surgery. Patients were excluded if they underwent explantation of a prior prosthesis at the time of their first recorded surgery. Statistical analysis was performed by Kaplan-Meier plot, hazard curve, and multivariate analysis adjusting for age, race, comorbidities, insurance status, hospital volume, and hospital teaching status. Primary outcome was reoperation, specified as the removal or replacement of the prosthesis. In total, 7,666 patients (40,932 patient-years) were included in the study. The 5- and 10-year cumulative reoperation rates were 11.2% (CI = 10.5-12.0) and 15.7% (CI = 14.7-16.8), respectively. Malfunction and infection accounted for 57% and 27% of reoperations. Reoperation rate was highest at 1 year postoperatively and steadily decreased until 2 years postoperatively. Multivariate analysis showed higher rates of reoperation in younger men (hazard ratio [HR] = 1.51, CI = 1.12-2.05), African-American men (HR = 1.30, CI = 1.05-1.62), and Hispanic men (HR = 1.32, CI = 1.12-1.57). Of the reoperations, 22.9% were performed at a hospital different from the initial implantation. Reoperation rate for penile prosthetic surgery is highest in the first year postoperatively. Patients with the highest risk for reoperation were African-American, Hispanic, and younger men. Nearly one fourth of reoperations occurred at a hospital different from the initial surgery, suggesting the existing literature does not reflect the true prevalence of penile prosthetic complications.