Surgical site infections after simultaneous pancreas kidney and pancreas transplantation in the Swiss Transplant Cohort Study.

BACKGROUND: Among hospital-acquired infections, surgical site infections (SSIs) are frequent. SSI in the early post-transplant course poses a relevant threat to transplant recipients. AIM: To determine incidence, risk factors for SSI and its association with post-transplant outcomes and pancreas transplant (P-Tx) recipients. METHODS: Adult simultaneous kidney-pancreas transplantation (SPK-T) and P-Tx recipients with a follow-up of at least 90 days were identified in the Swiss Transplant Cohort Study (STCS) dataset. Except for the categorization of SSIs according to Centers for Disease Control and Prevention (CDC) criteria, all other data were prospectively collected. Risk factors for SSI were investigated with logistic regression. A Weibull accelerated failure-time model was applied to address the impact of SSI on length of stay, correcting for transplant-related complications and delayed graft function. FINDINGS: Of 130 transplant recipients, 108 SPK-Tx and 22 P-Tx, 18 (14%) individuals developed SSI within the first 90 days after transplantation. Deep incisional (seven, 38.9%) and organ/space infections (eight, 44.4%) predominated. In the majority of SSIs (11, 61.1%; two SSIs with simultaneous identification of fungal pathogens) bacteria were detected with Enterococcus spp. being most frequent. The median duration of hospitalization after transplantation was significantly longer in recipients with SSI (median: 26 days; interquartile range (IQR): 19-44) than in patients without SSI (median: 17 days; IQR: 12-25; P = 0.002). In multivariate analysis, SSI was significantly associated with increased length of stay and prolonged the duration of hospitalization by 36% (95% confidence interval: 4-79). CONCLUSION: SSI after SPK-Tx and P-Tx occurred at a frequency of 14%. Among pathogens, Enterococcus spp. predominated. SSI was independently associated with a longer hospitalization after transplantation.

Clostridium difficile infection is associated with graft loss in solid organ transplant recipients.

Clostridium difficile infection (CDI) is a leading cause of infectious diarrhea in solid organ transplant recipients (SOT). We aimed to assess incidence, risk factors, and outcome of CDI within the Swiss Transplant Cohort Study (STCS). We performed a case-control study of SOT recipients in the STCS diagnosed with CDI between May 2008 and August 2013. We matched 2 control subjects per case by age at transplantation, sex, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors and evaluate outcome of CDI. Two thousand one hundred fifty-eight SOT recipients, comprising 87 cases of CDI and 174 matched controls were included. The overall CDI rate per 10 000 patient days was 0.47 (95% confidence interval ([CI] 0.38-0.58), with the highest rate in lung (1.48, 95% CI 0.93-2.24). In multivariable analysis, proven infections (hazard ratio [HR] 2.82, 95% CI 1.29-6.19) and antibiotic treatments (HR 4.51, 95% CI 2.03-10.0) during the preceding 3 months were independently associated with the development of CDI. Despite mild clinical presentations, recipients acquiring CDI posttransplantation had an increased risk of graft loss (HR 2.24, 95% CI 1.15-4.37; P = .02). These findings may help to improve the management of SOT recipients.

Preventive Strategies Against Cytomegalovirus and Incidence of α-Herpesvirus Infections in Solid Organ Transplant Recipients: A Nationwide Cohort Study.

We assessed the impact of antiviral preventive strategies on the incidence of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections in a nationwide cohort of transplant recipients. Risk factors for the development of HSV or VZV infection were assessed by Cox proportional hazards regression. We included 2781 patients (56% kidney, 20% liver, 10% lung, 7.3% heart, 6.7% others). Overall, 1264 (45%) patients received antiviral prophylaxis (ganciclovir or valganciclovir, n = 1145; acyclovir or valacyclovir, n = 138). Incidence of HSV and VZV infections was 28.9 and 12.1 cases, respectively, per 1000 person-years. Incidence of HSV and VZV infections at 1 year after transplant was 4.6% (95% confidence interval [CI] 3.5-5.8) in patients receiving antiviral prophylaxis versus 12.3% (95% CI 10.7-14) in patients without prophylaxis; this was observed particularly for HSV infections (3% [95% CI 2.2-4] versus 9.8% [95% CI 8.4-11.4], respectively). A lower rate of HSV and VZV infections was also seen in donor or recipient cytomegalovirus-positive patients receiving ganciclovir or valganciclovir prophylaxis compared with a preemptive approach. Female sex (hazard ratio [HR] 1.663, p = 0.001), HSV seropositivity (HR 5.198, p < 0.001), previous episodes of rejection (HR 1.95, p = 0.004), and use of a preemptive approach (HR 2.841, p = 0.017) were significantly associated with a higher risk of HSV infection. Although HSV and VZV infections were common after transplantation, antiviral prophylaxis significantly reduced symptomatic HSV infections.

Comparative assessment of the incidence of vertical root fractures between conventional versus surgical endodontic retreatment.

OBJECTIVES: Vertical root fractures (VRFs) are a common cause of tooth loss. Little evidence exists though, relating the incidence of VRFs to the type of endodontic retreatment. This retrospective study aimed at evaluating the impact of conventional versus surgical endodontics on root canal-filled teeth with VRFs. MATERIALS AND METHODS: Over a period of 13 years, 200 endodontically retreated teeth from 192 patients with VRFs were extracted and further examined. VRFs were assessed in relation to age, gender, tooth group, clinical signs, extension on the root surface, patency, as well as type of endodontic retreatment and restoration. Statistical analysis was conducted using a Cox PH Model, Chi-squared, Wilcoxon rank-sum, and Log rank tests at a significance level of 5 %. RESULTS: The majority of teeth with VRFs (62.31 %) had undergone the combination of conventional root canal retreatment and apical surgery. Women (64.06 %) presented VRFs more frequently than men (35.94 %) at the mean age of 51.1 and 55.1 years, respectively. Maxillary first (17.5 %) and second (16.5 %) premolars, restored by a resin-based material without a post (56.28 %) were more susceptible to VRFs. Apically initiated (84.1 %) VRFs could be diagnosed more easily on radiographs. CONCLUSIONS: The type of endodontic treatment strongly correlated with VRFs. The prevalence of VRFs in teeth having undergone both conventional and surgical endodontic retreatment could be attributed, among others, to additive dentin damage related to the aforementioned endodontic procedures. CLINICAL RELEVANCE: The possible involvement of endodontic retreatment in the multifactorial etiology of VRFs needs to be taken into consideration in clinical practice.

Evaluation of an improved endodontic teaching model: do preclinical exercises have an influence on the technical quality of root canal treatments?

AIM: To investigate whether the preclinical application of an electronic root canal length measurement device (ERCLMD) leads to more accurate working length (WL) determinations in a preclinical endodontic course and if this exercise effects the technical quality of root canal procedures when treatments are performed on patients for the first time. METHODOLOGY: Root canal treatments performed by two consecutive groups of third year students (group 1: n = 39, group 2: n = 44) were compared in the preclinical course and when root canal treatments were performed on patients in the following term. Two different teaching models were applied in the preclinical endodontic course. WL in group 1 was determined with radiographs only. The teaching model applied in group 2 allowed the application of an ERCLMD. When treatments were performed on patients, both groups used the same technique to determine WL. It was first determined using an ERCLMD and verified radiographically. Master cone and root filling lengths were evaluated using radiographs, and comparisons between both groups were made using Fischer's exact test. RESULTS: Root fillings performed by students of group 2 were more often classified as acceptable. This observation was made in the preclinical endodontic course and when treatments were performed on patients. CONCLUSIONS: The application of an ERCLMD in combination with radiographs is more accurate to determine WL than radiographs alone. Students practiced the use of ERCLMDs with the new model and benefited from this experience when performing their first root canal treatments on patients.

The use of cone beam computed tomography to predetermine root canal lengths in molar teeth: a comparison between two-dimensional and three-dimensional measurements.

OBJECTIVES: The aim of this study was to evaluate the accuracy of two-dimensional (2D) and three-dimensional (3D) root canal length measurements in molar teeth using cone beam computed tomography (CBCT). MATERIALS AND METHODS: Root canal lengths of twenty molar teeth were measured with two different CBCT approaches. After adjusting the CBCT images, 2D measurements were performed within the sagittal plane between the apical foramen and the coronal reference (cusp). The 3D approach measured centrically in axial planes. A linear mixed model with random intercepts was fitted to compare differences between methods (2D and 3D). The correlation between CBCT measurements and the actual root canal length was evaluated using the Pearson correlation coefficient. RESULTS: Differences between 3D measurements and the actual root canal lengths were significantly smaller compared to the 2D approach (p < 0.001). Mean differences were 0.32 and 0.58 mm, respectively. A high correlation was found between the actual root canal length and 3D measurements (Pearson correlation coefficient = 0.97). Compared to the actual root canal length, 80 % of the 3D measurements were within the limits of ±0.5 mm. CONCLUSIONS: 3D measurements of root canals in molar teeth are more accurate than simple 2D measurements and show a high correlation to the actual lengths. CLINICAL RELEVANCE: In cases where a CBCT is already available, root canal lengths in molar teeth can be accurately predetermined using a standardized 3D approach.

Five-year results of a prospective randomised controlled clinical trial of posterior computer-aided design-computer-aided manufacturing ZrSiO4 -ceramic crowns.

The aim of this prospective randomised controlled clinical trial was to evaluate the clinical outcome of shrinkage-free ZrSiO4 -ceramic full-coverage crowns on premolars and molars in comparison with conventional gold crowns over a 5-year period. Two hundred and twenty-three patients were included and randomly divided into two treatment groups. One hundred and twenty-three patients were restored with 123 ZrSiO4 -ceramic crowns, and 100 patients received 100 gold crowns, which served as the control. All crowns were conventionally cemented with glass-ionomer cement. After an observation period of 6, 12, 24, 36, 48 and 60 months, the survival probability (Kaplan-Meier) for the shrinkage-free ZrSiO4 -ceramic crowns was 98·3%, 92·0%, 84·7%, 79% and 73·2% and for the gold crowns, 99%, 97·9%, 95·7%, 94·6% and 92·3%, respectively. The difference between the test and control group was statistically significant (P = 0·0027). The gold crowns showed a better marginal integrity with less marginal discoloration than the ceramic crowns. The most common failure in the ceramic crown group was fracture of the crown. The 60-month results of this prospective randomised controlled clinical trial suggest that the use of these shrinkage-free ZrSiO4 -ceramic crowns in posterior tooth restorations cannot be recommended.

Success rates of prosthetic restorations on endodontically treated teeth; a systematic review after 6 years.

The aims of this systematic review were to investigate the success rates of prosthetic restorations on endodontically treated teeth and their manner of failure. PubMed and hand literature searches were conducted on studies published until June 2012. Only clinical studies on human subjects referring to the success rates of prosthetic restorations on endodontically treated teeth with a follow-up period of at least 6 years were reviewed. A total of four studies were identified. Meta-analysis showed the success rate to be 92% (CI 82-98%) for single crowns on endodontically treated teeth and 79% (72-86%) for fixed dental prostheses. Only one study reported on removable dental prostheses with a success rate of 66%. Single crowns on teeth restored without posts demonstrated a success rate of 94% (CI 84-99%), whereas where posts were placed, the success rate was lower (92% CI 82-98%). Single crowns over cast post-and-cores and prefabricated posts showed success rates of 93% (CI 82-99%) and 94% (CI 90-97%), respectively; both differences were not statistically significant (significance level of 5%). The most common reason for failure was post-debonding. Single crowns seem to be the best treatment modality for endodontically treated teeth. However, due to the low number of studies included and their design, the results of this systematic review should be interpreted with caution. Further clinical studies are needed to provide high-quality evidence on the topic.