The Use of Enamel Matrix Derivative during Surgical Therapy for Peri-Implantitis: A Case Series

Peri-implantitis is a growing concern and currently, there is no agreement on the best method for treating this condition. This study looked at surgical intervention with the use of enamel matrix derivative (EMD) for treating this condition. A cohort of 25 (34 implants) consecutive patients treated with EMD for peri-implantitis was followed for up to 6.4 years. The survival of the implants as well as changes in clinical parameters are reported. Statistical analysis was performed using paired t tests and general estimating equations. The mean length of time implants were followed post-surgery was 3.05 ± 1.53 years. All but two of the treated implants survived in function (94%). Both failed implants were lost in the same patient, who was a heavy smoker. The changes in mean probing depth (1.94 ± 1.18 mm), change in deepest probing depth (3.12 ± 1.45 mm), and reduction in bleeding on probing (73.6 ± 43.9%) according to patient means were all highly significant (p < 0.001 for all changes). When EMD is used during surgical treatment of peri-implantitis, there is a high survival rate of implants and significant improvements in clinical parameters.

A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067

Planets with radii between that of the Earth and Neptune (hereafter referred to as 'sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R⊕ to 2.85R⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.

Characterization of miR-335-5p and miR-335-3p in human osteoarthritic tissues

OBJECTIVE

We aimed to characterize the expression patterns, gene targets, and functional effects of miR-335-5p and miR-335-3p among seven primary human knee and hip osteoarthritic tissue types.

METHODS

We collected synovial fluid, subchondral bone, articular cartilage, synovium, meniscus/labrum, infrapatellar/acetabular fat, anterior cruciate ligament/ligamentum teres, and vastus medialis oblique/quadratus femoris muscle (n = 7-20) from surgical patients with early- or late-stage osteoarthritis (OA) and quantified miR-335-5p and miR-335-3p expression by real-time PCR. Predicted gene targets were measured in knee OA infrapatellar fat following miRNA inhibitor transfection (n = 3), and prioritized gene targets were validated following miRNA inhibitor and mimic transfection (n = 6). Following pathway analyses, we performed Oil-Red-O staining to assess changes in total lipid content in infrapatellar fat.

RESULTS

Showing a 227-fold increase in knee OA infrapatellar fat (the highest expressing tissue) versus meniscus (the lowest expressing tissue), miR-335-5p was more abundant than miR-335-3p (92-fold increase). MiR-335-5p showed higher expression across knee tissues versus hip tissues, and in late-stage versus early-stage knee OA fat. Exploring candidate genes, VCAM1 and MMP13 were identified as putative direct targets of miR-335-5p and miR-335-3p, respectively, showing downregulation with miRNA mimic transfection. Exploring candidate pathways, predicted miR-335-5p gene targets were enriched in a canonical adipogenesis network (p = 2.1e - 5). Modulation of miR-335-5p in late-stage knee OA fat showed an inverse relationship to total lipid content.

CONCLUSION

Our data suggest both miR-335-5p and miR-335-3p regulate gene targets in late-stage knee OA infrapatellar fat, though miR-335-5p appears to be more prominent, with tissue-, joint-, and stage-specific effects.

Liver Cirrhosis After the Fontan Procedure: Impact of Atrioventricular Valve Failure

BACKGROUND

Liver cirrhosis is now well recognized as a potential complication after the Fontan procedure, although associated risk factors and optimal timing of liver screening remain unclear.

METHODS

All patients who underwent an extracardiac conduit Fontan procedure at The Royal Children's Hospital, Melbourne, were identified using the Australia and New Zealand Fontan Registry. Cirrhosis was diagnosed based on liver biopsy, or a combination of imaging findings and clinical evaluation by a hepatologist.

RESULTS

Between 1997 and 2020, 398 patients underwent an extracardiac conduit Fontan procedure at our center, and 276 had ongoing follow-up in Victoria. Ninety-five patients (34%) underwent liver assessment at a mean age of 18.2 ± 6.7 years (11.8 ± 5.5 years post-Fontan). Fifteen patients (16%) were diagnosed with cirrhosis at a mean age of 22.7 ± 5.9 years (14.0 ± 5.2 years post-Fontan). The need for prior or concomitant atrioventricular valve repair or replacement was associated with an increased risk of cirrhosis (univariable hazard ratio [HR] 7.09, 95% confidence interval [CI] 2.13-23.61, P = .001). By multivariable analysis, factors associated with development of cirrhosis were atrioventricular valve failure prior to Fontan (HR 3.27, 95% CI 1.15-9.31, P = .026) and older age at Fontan operation (HR 1.13 per year increase, 95% CI 1.01-1.26, P = .034). The proportion of patients alive, nontransplanted, and without cirrhosis at 10, 15, and 20 years was 93.4% (95% CI 88.4%-98.7%), 79.6% (95% CI 69.7%-90.8%), and 64.6% (95% CI 51.0%-81.9%), respectively.

CONCLUSIONS

Early commencement of liver screening should be considered for patients with a history of atrioventricular failure during Fontan palliation.

A dense ring of the trans-Neptunian object Quaoar outside its Roche limit

Planetary rings are observed not only around giant planets1, but also around small bodies such as the Centaur Chariklo2 and the dwarf planet Haumea3. Up to now, all known dense rings were located close enough to their parent bodies, being inside the Roche limit, where tidal forces prevent material with reasonable densities from aggregating into a satellite. Here we report observations of an inhomogeneous ring around the trans-Neptunian body (50000) Quaoar. This trans-Neptunian object has an estimated radius4 of 555 km and possesses a roughly 80-km satellite5 (Weywot) that orbits at 24 Quaoar radii6,7. The detected ring orbits at 7.4 radii from the central body, which is well outside Quaoar's classical Roche limit, thus indicating that this limit does not always determine where ring material can survive. Our local collisional simulations show that elastic collisions, based on laboratory experiments8, can maintain a ring far away from the body. Moreover, Quaoar's ring orbits close to the 1/3 spin-orbit resonance9 with Quaoar, a property shared by Chariklo's2,10,11 and Haumea's3 rings, suggesting that this resonance plays a key role in ring confinement for small bodies.

Prolonged Enteral Tube Feeding in Infants With a Functional Single Ventricle Is Associated With Adverse Outcomes After Fontan Completion

OBJECTIVES

To define the baseline characteristics of long-term tube-fed single ventricle patients, investigate associations between long-term enteral tube feeding and growth, and determine associations with long-term outcomes after Fontan procedure.

STUDY DESIGN

We performed a retrospective cohort study of patients in the Australia and New Zealand Fontan Registry undergoing treatment at the Royal Children's Hospital, the Children's Hospital at Westmead, Royal Melbourne Hospital, and Royal Prince Alfred Hospital from 1981-2018. Patients were defined as tube-fed (TF) or non-tube-fed (NTF) based on enteral tube feeding at age 90 days. Feeding groups were compared regarding BMI trajectory, BMI at last follow-up, and long-term incidence of severe Fontan failure.

RESULTS

Of 390 patients (56(14%) TF, 334(86%) NTF), TF was associated with right ventricular dominance, hypoplastic left heart syndrome, Norwood procedure, increased procedures prior to Fontan, extracardiac conduit Fontan, Fontan fenestration, and atrioventricular valve repair/replacement. TF patients were less likely to be in the higher compared with lowest 0-6 month BMI trajectory (P<0.01,P=0.03), had lower 6month weight-for-age z-scores (P<0.01) and length-for-age z-scores (P=0.01). TF were less likely to be overweight/obese at pediatric follow-up (HR=0.31,95%CI:0.12-0.80;P=0.02) and more likely to be underweight at adult follow-up ((HR=16.51; 5%CI:2.70-101.10;P<0.01).TF compared with NTF was associated with increased risk of severe Fontan failure (HR=4.13;95%CI=1.65,10.31;P<0.01).

CONCLUSIONS

Prolonged infant enteral tube feeding is an independent marker of poor growth and adverse clinical outcomes extending long-term post-Fontan procedure.

Prevalence of irritable bowel syndrome and functional abdominal pain disorders in children with inflammatory bowel disease in remission

Despite evidence of an increased prevalence of irritable bowel syndrome (IBS) in adults with inflammatory bowel disease (IBD) compared with the general population, the prevalence of IBS in children with IBD is unclear. In this review, we aimed to identify the reported prevalence of IBS or functional abdominal pain disorders (FAPDs) in children with IBD in remission. A search of three databases (MEDLINE, Embase, and PubMed) was performed to identify studies reporting the prevalence of IBS or FAPDs in pediatric patients with IBD in remission. A total of 60 studies were identified, with four eligible studies remaining following abstract screening. In children with IBD in remission, the overall prevalence of IBS ranged between 3.9 and 16.1%, and the overall prevalence of FAPDs ranged between 9.6 and 29.5%. The prevalence of FAPDs in patients in biomarker-based remission was generally higher than those in clinical remission (range 16-22.5% vs 9.6-16.7%, respectively). There is a paucity of literature reporting on the prevalence of IBS or FAPDs in children with IBD in remission. Despite the differences in criteria used to define IBD remission in the included articles, there seems to be an increased overall prevalence of IBS or FAPDs in children with IBD.

Body Mass Index Trajectory and Outcome Post Fontan Procedure

Background Patients with a single ventricle who experience early life growth failure suffer high morbidity and mortality in the perisurgical period. However, long-term implications of poor infant growth, as well as associations between body mass index (BMI) and outcome in adulthood, remain unclear. We aimed to model BMI trajectories of patients with a single ventricle undergoing a Fontan procedure to determine trajectory-based differences in baseline characteristics and long-term clinical outcomes. Methods and Results We performed a retrospective analysis of medical records from patients in the Australia and New Zealand Fontan Registry receiving treatment at the Royal Children's Hospital, The Children's Hospital at Westmead, Royal Melbourne Hospital, and Royal Prince Alfred Hospital from 1981 to 2018. BMI trajectories were modeled in 496 patients using latent class growth analysis from 0 to 6 months, 6 to 60 months, and 5 to 16 years. Trajectories were compared regarding long-term incidence of severe Fontan failure (defined as mortality, heart transplantation, Fontan takedown, or New York Heart Association class III/IV heart failure). Three trajectories were found for male and female subjects at each age group-lower, middle, higher. Subjects in the lower trajectory at 0 to 6 months were more likely to have an atriopulmonary Fontan and experienced increased mortality long term. No association was found between higher BMI trajectory, current BMI, and long-term outcome. Conclusions Poor growth in early life correlates with increased long-term severe Fontan failure. Delineation of distinct BMI trajectories can be used in larger and older cohorts to find optimal BMI targets for patient outcome.

Surveillance of End-Organ Damage in Fontan Patients Prior to Transition to Adult Care: Are We There Yet?

BACKGROUND

Recently published guidelines and consensus statements have outlined recommended screening practices for monitoring of end-organ dysfunction in Fontan patients. We reviewed the current approach to end-organ screening in a local population of Fontan patients at the time of transition to adult care.

METHODS

Patient data from the Australia and New Zealand Fontan Registry and patient medical records were used to review investigations performed in Fontan patients transitioned from The Royal Children's Hospital Melbourne to an adult centre between 1 July 2015 and 30 June 2020.

RESULTS

A total of 32 patients were referred for transition to an adult centre between 1 July 2015 and 30 June 2020 at a mean age of 18.5±0.7 years (12.7±2.5 years post-Fontan). Liver function tests were performed in 22 patients (69%) within 5 years prior to transition and were abnormal in 15 patients (68%). Liver ultrasound was performed in 13 patients (41%) within 5 years prior to the date of transition, of whom 10 (77%) had abnormal findings (features suggestive of hepatic fibrosis in seven [54%], cirrhosis in two [15%], and portal hypertension in three [23%]). Fourteen (14) patients (44%) had no record of a liver ultrasound being performed between the date of the Fontan procedure and the time of transition to adult care. Hepatocellular carcinoma was diagnosed in one patient at 18 months following transition. A total of 24 patients (75%) had a serum creatinine measured within the 5 years prior to transition, and two (8%) had an estimated glomerular filtration rate (eGFR) less than 90 ml/min/1.73 m². No patient had a urine protein-creatinine ratio measured between the date of the Fontan procedure and the time of transition to adult care.

CONCLUSIONS

In this study we have identified that the majority of patients transitioned from a tertiary paediatric centre to an adult centre within the last 5 years did not undergo routine surveillance for end-organ dysfunction. Routine screening for end-organ complications of the Fontan circulation should be incorporated into clinical practice and is an important part of Fontan patient care both pre- and post-transition to adult services.

Correlation between tumor voxel dose response matrix and tumor biomarker profile in patients with head and neck squamous cell carcinoma

BACKGROUND

We have developed a novel imaging analysis procedure that is highly predictive of local failure after chemoradiation in head and neck cancer. In this study we investigated whether any pretreatment biomarkers correlated with key imaging parameters.

METHODS

Pretreatment biopsy material was available for 28 patients entered into an institutional trial of adaptive radiotherapy in which FDG-PET images were collected weekly during treatment. The biopsies were immunohistochemically stained for CD44, EGFR, GLUT1, ALDH1, Ki-67 and p53 and quantified using image analysis. Expression levels were correlated with previously derived imaging parameters, the pretreatment SUV_max and the dose response matrix (DRM).

RESULTS

The different parameters of the SUV_max and DRM did not correlate with each other. We observed a positive and highly significant (p = 0.0088) correlation between CD44 expression and volume of tumor with a DRM greater than 0.8. We found no correlation between any DRM parameter and GLUT1, p53, Ki-67 and EGFR or ALDH1. GLUT1 expression did correlate with the maximum SUV₀ and the volume of tumor with an SUV₀ greater than 20.

CONCLUSIONS

The pretreatment SUV_max and DRM are independent imaging parameters that combine to predict local recurrence. The significant correlation between CD44 expression, a known cancer stem cell (CSC) marker, and volume of tumor with a DRM greater than 0.8 is consistent with concept that specific foci of cells are responsible for tumor recurrence and that CSCs may be randomly distributed in tumors in specific niches. Dose painting these small areas may lead to improved tumor control.

Low Dose Brain Irradiation Reduces Amyloid-β and Tau in 3xTg-AD Mice

We have previously reported that low doses of external beam ionizing irradiation reduced amyloid-β (Aβ) plaques and improved cognition in APP/PS1 mice. In this study we investigated the effects of radiation in an age-matched series of 3xTg-AD mice. Mice were hemibrain-irradiated with 5 fractions of 2 Gy and sacrificed 8 weeks after the end of treatment. Aβ and tau were assessed using immunohistochemistry and quantified using image analysis with Definiens Tissue Studio. We observed a significant reduction in Aβ plaque burden and tau staining; these two parameters were significantly correlated. This preliminary data is further support that low doses of radiation may be beneficial in Alzheimer's disease.

Cross-sectional assessment of haemostatic profile and hepatic dysfunction in Fontan patients

Background

Fontan-associated liver disease is accompanied by a hypercoagulable state. While hepatic dysfunction in Fontan patients is common, its relationship with haemostatic changes and clinical outcomes in this patient population remains unclear.

Objective

To correlate liver dysfunction and haemostatic profiles with clinical outcomes in the Fontan population.

Patients/methods

Patients were enrolled in a multicentre, cross-sectional study in Australia and New Zealand. Hepatic structure and function were assessed using serum-based calculations (Fibrotest and model for end-stage liver disease excluding international normalised ratio scores). Haemostatic profiles were assessed by Thrombin Generation. Platelet function was assessed via Platelet Factor 4 (PF4) and P-selectin (P-SEL). Clinical outcomes were obtained from the Australian and New Zealand Fontan Registry.

Results

Seventy-three patients participated in the study (mean age 18.9±8.5 years with a mean of 13.5±6.9 years post-Fontan). The Endogenous Thrombin Potential (ETP) for patients who suffered thrombotic events (TE) (1366.4±66.2 nM/min) was higher compared with patients with major bleeding events (1011.1±138.4 nM/min) (p=0.03). Except for a negative correlation between Fibrotest-score and PF4 (p=0.045), PF4 and P-SEL concentrations did not correlate with markers of hepatic dysfunction or structural abnormality.

Conclusions

Increased ETP is associated with TE during clinical follow-up after Fontan. This study reinforces that hepatic dysfunction may contribute to the derangement of coagulation factors, impacting the individual risk of haemostatic complications for the Fontan population.

Treating brain metastases in melanoma: What is the optimal CNS-directed and systemic management?

Treatments for melanoma have significantly advanced with the approval of targeted treatments against the BRAF/MEK pathway and immunotherapy in the form of checkpoint inhibitors. Studies have shown the effectiveness of these treatments against brain metastases. However, the optimum treatment strategy utilising CNS-directed treatments such as stereotactic radiosurgery (SRS) and neurosurgical resection is less clear. Over six years, 70 patients with metastatic melanoma were treated for brain metastases at a tertiary treatment centre. The median overall survival (OS) for all patients was 10.2 months. 51 patients received localised treatment; 7 resection (median OS 10 months), 11 resection and SRS (median OS 17.3 months) and 33 SRS alone (median OS 17.4 months). For patients treated with SRS those who had <2 cm³ treated had a better median OS (20.5 months) compared to those who had >2 cm³ treated (12 months). 69 Patients received systemic treatment. The median OS of patients who did not have CNS-directed treatment was poor (median OS 1.2 months). Patients treated with first line dual immunotherapy had the best median OS (26.7 months), compared to anti-PD-1 (14.1 months), ipilimumab (14.3 months) and kinase inhibitors (10.9 months). Despite advancements in treatment, the development of brain metastases in melanoma is associated with worse outcomes. A combination of CNS-directed and systemic treatment is important to improve survival. Dual immunotherapy appears to be the most effective systemic treatment and the use of SRS improved outcomes. As metastatic melanoma treatments evolve there need to be an ongoing focus to ensure these strategies adequately treat intracranial disease.

Acute and Chronic Kidney Disease Following Congenital Heart Surgery: A Review

BACKGROUND

There is an increasing prevalence of chronic kidney disease in the population of adults currently living with congenital heart disease. A considerable proportion of children who undergo congenital heart surgery experience postoperative acute kidney injury. Whether there is an association between acute kidney injury after cardiac surgery in childhood and development of chronic kidney disease is unclear.

METHODS

Three electronic databases were searched to capture relevant studies exploring the relationship between acute kidney injury after congenital heart surgery in children and progression to chronic kidney disease.

RESULTS

A literature search identified a total of 212 research articles, 7 of which were selected for in-depth review.

CONCLUSIONS

There is a likely association between acute kidney injury in children undergoing congenital heart surgery and progression to chronic kidney disease. Research should be developed to mitigate factors contributing to postoperative acute kidney injury in neonates, infants, and children undergoing cardiac surgery. Better targeted follow-up protocols to monitor renal function in children undergoing cardiac surgery should be implemented. A universal definition for acute kidney injury and chronic kidney disease is needed to improve detection and research in this field.

Dacomitinib and gedatolisib in combination with fractionated radiation in head and neck cancer

•

We evaluated radiation with dual EGFR and PI3K targeting in head and neck cancer.

•

Dacomitinib, showed an inverse correlation between growth inhibition and EGFR expression.

•

Gedatolisib was effective in each cell line. Neither drug caused radiosensitization in vitro.

•

Gedatolisib was relatively ineffective in vivo in combination with dacomitinib and/or radiation.

•

Dacomitinib was highly effective alone and in combination with radiation and/or gedatolisib.

•

Immunoblotting studies in vivo mirrored the effects seen with growth delay.

Background and purpose

There has been little success targeting individual genes in combination with radiation in head and neck cancer. In this study we investigated whether targeting two key pathways simultaneously might be more effective.

Materials and methods

We studied the effect of combining dacomitinib (pan-HER, irreversible inhibitor) and gedatolisib (dual PI3K/MTOR inhibitor) with radiation in well characterized, low passage xenograft models of HNSCC in vitro and in vivo.

Results

Dacomitinib showed differential growth inhibition in vitro that correlated to EGFR expression whilst gedatolisib was effective in both cell lines. Neither agent radiosensitized the cell lines in vitro. In vivo studies demonstrated that dacomitinib was an effective agent alone and in combination with radiation whilst the addition of gedatolisib did not enhance the effect of these two modalities despite inhibiting phosphorylation of key genes in the PI3K/MTOR pathway.

Conclusions

Our results showed that combining two drugs with radiation provided no added benefit compared to the single most active drug. Dacomitinib deserves more investigation as a radiation sensitizing agent in HNSCC.

Effects of multiple implantations of titanium healing abutments: Surface characteristics and microbial colonization

OBJECTIVE

Very few studies have investigated dental implant components involved in the early stage of healing, especially the implant healing abutment (IHA), despite its vital role in soft tissue contouring and shaping after implant placement. Although these components are labelled by the manufacturer for "single-use only," it is a common clinical practice to clean, sterilize, and reuse them.

METHODS

In the present study, IHAs after single and multiple implantations were retrieved as per standard procedures, and biological material isolated from the surface was subjected to 16S rRNA sequence analysis. The microbiome analysis was followed by cleaning and sterilization in order to replicate clinical sterilization techniques. Following sterilization, retrievals were subjected to surface characterization with optical and scanning electron microscopy to investigate surface features, and electrochemical testing was performed to evaluate corrosion behavior.

RESULTS

The microbiota was comprised of early colonizers including Streptococcus species and secondary anaerobic colonizers such as Fusobacterium, Capnocytophaga, and Prevotella species. The surface analysis revealed that irrespective of the cleaning and sterilization techniques, the pristine, homogeneous surface of the new, unused IHAs could not be restored. Both single and multiple-use IHAs had severe surface changes including discoloration, major abrasions, biological contamination, and the IHA retrievals exhibited higher corrosion rate as compared to control specimens.

SIGNIFICANCE

Reusing IHAs multiple times may not be a prudent practice as the microbial colonization and surface changes caused by using this component multiple times may affect the performance of IHAs in soft tissue healing.

Bone loss around implants-is it metallosis?

Most would agree that the etiology of dental implant failure is related to oral biofilm. At present one group of scientists and clinicians feel that biofilm is solely responsible for bone loss around the devices. However, there is strong evidence that particles and ions of titanium released into the surrounding tissues by the action of biofilm and/or mechanical forces, a process termed metallosis, can be responsible for bone loss around some dental implants. These findings are reinforced by similar responses found around failed metal on metal joint prostheses. Both possible etiologies are discussed in detail in this commentary.

Treating Brain Metastases from Breast Cancer: Outcomes after Stereotactic Radiosurgery

AIMS

Stereotactic radiosurgery (SRS) is an alternative to surgery or whole brain radiotherapy for the control of single or multiple brain metastases in patients with breast cancer. To date, there is no clear consensus on factors that might predict overall survival following SRS. The aim of this study was to assess the overall survival of breast cancer patients with brain metastases treated with SRS at a single centre and to examine the factors that might influence survival.

MATERIALS AND METHODS

A retrospective analysis of consecutive patients with breast cancer and brain metastases, considered suitable for SRS by the regional neuro-oncology multidisciplinary team. All patients were treated at a single National Health Service centre.

RESULTS

In total, 91 patients received SRS between 2013 and 2017, of whom 15 (16.5%) were alive at the time of analysis. The median overall survival post-SRS was 15.7 months (interquartile range 7.7-23.8 months) with no significant effect of age on survival (67 patients ≤ 65 years, 16.3 months; 26 patients > 65 years, 11.4 months, P = 0.129). The primary tumour receptor status was an important determinant of outcome: 31 oestrogen receptor positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-) patients had a median overall survival of 13.8 months, 14 ER+/HER2+ patients had a median overall survival of 21.4 months, 30 ER-/HER2+ patients had a median overall survival of 20.4 months and 16 patients with triple negative breast cancer (TNBC) had a median overall survival of 8.5 months. A larger total volume of tumour treated (>10 cm³), but not the number of individual metastases treated, was associated with worse survival (P = 0.0002) in this series. Patients with stable extracranial disease at the time of SRS had improved overall survival compared with those with progressive extracranial disease (30 patients stable extracranial disease overall survival = 20.1 months versus 33 patients progressive extracranial disease overall survival = 11.4 months; P = 0.0011). Seventeen patients had no extracranial disease at the time of SRS, with a median overall survival of 13.1 months.

CONCLUSIONS

This single-centre series of consecutive patients with brain metastases from breast cancer, treated with SRS, had a similar overall survival compared with previous studies of SRS. TNBC and ER+/HER2- histology, metastatic volumes >10 cm³ and progressive extracranial disease at the time of SRS were associated with worse survival.

Fontan-associated nephropathy: Predictors and outcomes

BACKGROUND

Nephropathy is a known complication of the Fontan circulation, but its determinants have not been identified and patient outcomes are also still unknown.

METHODS

The Australia and New Zealand Fontan Registry was used to identify those who underwent Fontan operation before and survived beyond 16-years-old with an intact Fontan circulation. Serum creatinine values were collected for each patient between 16 and 25 years and at recent follow-up. The Modification of Diet in Renal Disease (MDRD) equation was used to calculate eGFR. Patient outcomes were obtained from the Registry. Fontan failure was defined as death, transplantation, plastic bronchitis, protein losing enteropathy, Fontan takedown and NYHA class III-IV.

RESULTS

Serum creatinine measurements were available for 328 patients. Renal dysfunction was defined as eGFR <90 mL/min/1.72m². Renal dysfunction was present in 67/328 (20%) and 3/328 (1%) patients had an eGFR <60 mL/min/1.72m². The 10-year survival and 10-year freedom from death and transplantation were the same, 96% (95% CI: 0.9-1) for those with renal dysfunction, and 89% (0.83-0.95; p = 0.1) and 87% (95% CI: 0.81-0.94; p = 0.05) for patients without dysfunction. The 10-year freedom from failure were also similar, 83% (95% CI: 0.70-0.97) for those without renal dysfunction vs 80% (95% CI: 0.74-0.89; p = 0.84). There was no change in mean eGFR for the renal dysfunction group over a mean of 8 ± 5.5 years.

CONCLUSION

By the time they reach adulthood, 20% of patients with a Fontan circulation have renal dysfunction by eGFR calculation. Over the course of one decade, Fontan-associated nephropathy appears well tolerated.

Prognostic significance of MTOR expression in HPV positive and negative head and neck cancers treated by chemoradiation

BACKGROUND

The mechanistic target of rapamycin (MTOR) plays a key role in regulating cell growth and metabolism and is commonly overexpressed in head and neck cancer (HNSCC). This study investigated the association of MTOR with clinical outcome in human papilloma virus (HPV) positive and negative HNSCC patients treated by chemoradiation.

METHODS

A tissue microarray (TMA) consisting of cores from 109 HNSCC patients treated by definitive chemoradiation was constructed and stained with antibodies against p16 and MTOR and expression correlated with clinicopathological features and clinical outcome.

RESULTS

MTOR varied widely between tumor cores and was not associated with HPV status or clinicopathological features. There was a positive correlation with pre-treatment FDG uptake. (P = .01). In HPV negative patients, MTOR predicted for shorter locoregional control (P = .02), diseases free survival (P = .02), and overall survival (P = .04). MTOR expression was not associated with outcome in HPV positive patients.

CONCLUSIONS

Prognostic significance of MTOR expression depends on HPV status.

Creatinine-based estimation of glomerular filtration rate in patients with a Fontan circulation

BACKGROUND

Patients with a Fontan circulation are at risk of renal dysfunction. We analyzed cross-sectional data in pediatric and adult Fontan patients in order to assess the accuracy of commonly used serum creatinine-based methods in estimating glomerular filtration rate (GFR).

METHODS

A total of 124 Fontan patients (58 children, 66 adults) were enrolled across three study centers. Measurement of GFR (mGFR) using in vivo ^99m Tc-DTPA clearance was performed. Various serum creatinine-based equations were used to calculate estimated GFR (eGFR).

RESULTS

Mean mGFR was 108 ± 28 mL/min/1.73 m² in children and 92 ± 20 mL/min/1.73 m² in adults. Fourteen children (25%) and 28 adults (45%) had an mGFR <90 mL/min/1.73 m² . There was no significant correlation between mGFR and eGFR (Schwartz) in children (r = 0.22, P = .1), which substantially overestimated mGFR (bias 50.8, 95%CI: 41.1-60.5 mL/min/1.73 m² , P < .0001). The Bedside Schwartz equation also performed poorly in the children (r = 0.08, P = .5; bias 5.9, 95%CI: -2.9-14.6 mL/min/1.73 m² , P < .0001). There was a strong correlation between mGFR and both eGFR (CKD-EPI) and eGFR (MDRD) in adults (r = 0.67, P < .0001 in both cases), however, both methods overestimated mGFR (eGFR(CKD-EPI):bias 23.8, 95%CI: 20-27.6 mL/min/1.73 m² , P < .0001; eGFR (MDRD):bias 16.1, 95%CI: 11.8-20.4 mL/min/1.73 m² , P < .0001). None of the children with an mGFR <90 mL/min/1.73 m² had an eGFR (Schwartz) <90 mL/min/1.73 m² . Sensitivity and specificity of eGFR (CKD-EPI) and eGFR (MDRD) for mGFR <90 mL/min/1.73 m² in adults were 25% and 92% and 39% and 100%, respectively.

CONCLUSIONS

This study identifies the unreliability of using creatinine-based equations to estimate GFR in children with a Fontan circulation. The accuracy of formulas incorporating cystatin C should be further investigated and may aid noninvasive surveillance of renal function in this population.

The role of bacterial biofilm and mechanical forces in modulating dental implant failures

Currently many assume that bacteria are the primary etiological factor associated with failure of titanium dental implants. However, emerging data indicates a possible role for mechanical forces in implant failure. This study is based on the hypothesis that the synergistic effect of mechanical forces and bacterial biofilm can lead to surface damage resulting in in vivo release of metallic particles. The primary aim of the study was to develop a dynamic fatigue test method for dental implants immersed in wet environments such as; (i) 0.01 M phosphate buffer saline (PBS); (ii) lactic acid (pH = 5); (iii) bacterial polyculture. Four dental implants each were subjected to fatigue loading from 45 N to 450 N at 4 Hz for 2 million cycles while immersed in (i) PBS (negative control); (ii) bacterial culture (test); and (iii) lactic acid (positive control). Post-testing, optical microscopy, x-ray photoelectron spectroscopy, and electrochemical corrosion tests were performed to evaluate the surface morphology, chemistry, and potential, respectively, of titanium implants. Post-testing, surface discoloration was evident in all three groups. However, the surface damage was further established in XPS analyses of test specimens, which showed that the interplay of bacterial biofilm and mechanical forces resulted in thinning of the TiO₂. Lower corrosion potential (Ecorr) of the test specimens compared to positive and negative controls also illustrated damage to the oxide layer. However, other electrochemical parameters such as linear polarization resistance (LPR) and corrosion rate (CR) were comparable among the groups indicating the corrosion resistance post-testing. The synergistic effect of cyclic occlusal loading and bacteria biofilm could negatively affect the surface of titanium dental implants.

Titanium particles generated during ultrasonic scaling of implants

BACKGROUND

There is growing concern that titanium particles may play a role in peri-implant breakdown. Ultrasonic scalers are routinely used in the debridement of peri-implant lesions. This in vitro study is designed to evaluate if titanium particles are produced when an ultrasonic scaler is used on an implant.

METHODS

New sandblasted, large grit, acid etched (SLA) coated implants were subjected to ultrasonic scaling with stainless steel, titanium, and PEEK plastic tips. The implants were placed in a holding device and the ultrasonic scaler was positioned on the SLA surface under 25 grams of pressure. The implants were subjected to 30 scaling motions. The ultrasonic coolant water was collected and the number of metallic particles were counted under a light microscope. The particles were confirmed to be titanium via elemental analysis. The implants were visually evaluated for damage to the SLA coating.

RESULTS

No metallic particles were detected in the water supplied to the ultrasonic scalers (passive control). Metallic particles were detected when implants were subjected to the ultrasonic coolant water only without the scaler tip touching the implant (active control). All implants that were scaled produced metallic particles and showed easily detectable damage to the SLA layer.

CONCLUSIONS

All ultrasonic scaling caused the production of titanium particles and caused damage to the SLA coating of the implant. Ultrasonic scalers should be used with great caution in the treatment of peri-implant conditions and care should be taken to not touch the SLA surface of the implant.

Dual blockade of PI3K and MEK in combination with radiation in head and neck cancer

Background and purpose

In this study we have combined fractionated radiation treatment (RT) with two molecular targeted agents active against key deregulated signaling pathways in head and neck cancer.

Materials and methods

We used two molecularly characterized, low passage HNSCC cell lines of differing biological characteristics to study the effects of binimetinib and buparlisib in combination with radiation in vitro and in vivo.

Results

Buparlisib was active against both cell lines in vitro whereas binimetinib was more toxic to UT-SCC-14. Neither agent modified radiation sensitivity in vitro. Buparlisib significantly inhibited growth of UT-SSC-15 alone or in combination with RT but was ineffective in UT-SCC-14. Binimetinib did cause a significant delay with RT in UT-SCC-14 and it significantly reduced growth of the UT-SCC-15 tumors both alone and with RT. The tri-modality treatment was not as effective as RT with a single effective agent.

Conclusions

No significant benefit was gained by the combined use of the two agents with RT even though each was efficacious when used alone.

Surface characterization of titanium implant healing abutments before and after placement

BACKGROUND

Implant healing abutments (IHA) have a vital role in soft tissue healing after implant placement. Although there is thorough investigation on the implant surface, little is known about the effects potentially damaging oral conditions impose on healing abutments.

PURPOSE

To characterize the surface of titanium healing abutments before and after clinical placement to understand the effects of the oral environment and time on the device surface.

MATERIALS AND METHODS

Ten regular Straumann IHA were subjected to characterization pre and postplacement to elucidate the effects of the oral environment on device surfaces. Changes in surface crystallinity, morphology, and elemental composition were monitored with Raman spectroscopy, scanning electron microscopy, optical microscopy, and x-ray photoelectron spectroscopy, respectively. In addition, corrosion rate and polarization resistance were obtained to assess electrochemical device stability after placement.

RESULTS

Control analysis indicated the titanium oxide of IHAs was thicker than natural commercially pure titanium and had the structure of crystalline anatase. After removal, the abutments possessed large amounts of biological debris, visible scratches, and discoloration sparsely on the surface. Spectroscopic analysis revealed the titanium oxide on the surface of IHAs was structurally unchanged, with crystalline titanium dioxide still present on the surface. Electrochemical results revealed that implanted healing abutments possessed a significantly higher corrosion rate than controls (change in corrosion rate = 2.34 ± 0.58 nm/year).

CONCLUSIONS

Healing abutments were stable in the oral environment due to the chemical stability of the oxide, and were likely subjected to abrasions from unintentional loading and oral hygiene techniques.

Tapered Implants in Dentistry: Revitalizing Concepts with Technology: A Review

The most common approach to lessen treatment times is by decreasing the healing period during which osseointegration is established. Implant design parameters such as implant surface, primary stability, thread configuration, body shape, and the type of bone have to be considered to obtain this objective. The relationship that exists between these components will define the initial stability of the implant. It is believed implant sites using a tapered design and surface modification can increase the primary stability in low-density bone. Furthermore, recent experimental preclinical work has shown the possibility of attaining primary stability of immediately loaded, tapered dental implants without compromising healing and rapid bone formation while minimizing the implant stability loss at compression sites. This may be of singular importance with immediate/early functional loading of single implants placed in poor-quality bone. The selection of an implant that will provide adequate stability in bone of poor quality is important. A tapered-screw implant design will provide adequate stability because it creates pressure on cortical bone in areas of reduced bone quality. Building on the success of traditional tapered implant therapy, newer tapered implant designs should aim to maximize the clinical outcome by implementing new technologies with adapted clinical workflows.

Twenty-Five Year Outcomes of the Lateral Tunnel Fontan Procedure

The objective of this study was to characterize late outcomes of the lateral tunnel (LT) Fontan procedure. The outcomes of all patients who underwent an LT Fontan procedure in Australia and in New Zealand were analyzed. Original files were reviewed and outcomes data were obtained through a binational registry. Between 1980 and 2014, a total of 301 patients underwent an LT Fontan procedure across 6 major centers. There were 13 hospital mortalities, 21 late deaths, 8 Fontan conversions and revisions, 8 Fontan takedowns, and 4 heart transplantations. Overall survival at 15 and 25 years was 90% (95% confidence interval [CI]: 86%-93%) and 80% (95% CI: 69%-91%), respectively. Protein-losing enteropathy or plastic bronchitis was observed in 14 patients (5%). Freedom from late failure at 15 and 25 years was 88% (95% CI: 84%-92%) and 82% (95% CI: 76%-87%), respectively. Independent predictors of late Fontan failure were prolonged pleural effusions post Fontan operations (hazard ratio [HR] 3.06, 1.05-8.95, P = 0.041), age >7 years at Fontan (vs 3-5 years, HR 9.7, 2.46-38.21, P = 0.001) and development of supraventricular tachycardia (HR 4.67, 2.07-10.58, P < 0.001). Freedom from tachy- or bradyarrhythmias at 10 and 20 years was 87% (95% CI: 83%-91%) and 72% (95% CI: 66%-79%), respectively. Thromboembolic events occurred in 45 patients (16%, 26 strokes), and freedom from symptomatic thromboembolism at 10 and 20 years was 93% (95% CI: 89%-96%) and 80% (95% CI: 74%-86%), respectively. Over a 25-year period, the LT technique has achieved excellent late survival. As this population ages, it is at an increasing risk of failure and adverse events. We are likely to see an increasing proportion requiring heart transplantation and late reintervention.

The significance of Trk receptors in pancreatic cancer

This study investigated the Trk receptor family as a therapeutic target in pancreatic ductal adenocarcinoma and assessed their prognostic significance. Global gene expression analysis was investigated in prospectively collected pancreatic ductal adenocarcinomas that had either undergone neoadjuvant chemoradiation or were treated by surgery. PANC-1 and MIA-PaCa-2 cell lines were investigated to establish whether fractionated radiation altered expression of four neuroendocrine genes and whether this resulted in subsequent changes in radiosensitivity. A specific inhibitor of TrkA, B, and C, AstraZeneca 1332, was investigated in vitro and in vivo in combination with radiation. A tissue microarray was constructed from 77 pancreatic ductal adenocarcinoma patients who had undergone neoadjuvant chemoradiation and the Trk receptor, and neurogenic differentiation 1 expression was assessed and correlated with overall survival. A total of 99 genes were identified that were differentially expressed in the chemoradiation patients with neuroendocrine genes and pathways, in particular the neurogenic differentiation 1 and Trk receptor family, being prominent. Fractionated radiation upregulated the expression of neuroendocrine genes, and AstraZeneca 1332 treatment in vitro enhanced radiosensitivity. No added effect of AstraZeneca 1332 was observed in vivo. Trk receptor expression varied between isoforms but did not correlate significantly with clinical outcome. Radiation treatment upregulated neuroendocrine gene expression but the Trk receptor family does not appear to be a promising treatment target.

An extremely rare case of a high-grade pleomorphic cardiac sarcoma and likely cerebral metastasis in a young patient

To date, there have been less than a 100 confirmed case reports of primary cardiac malignant fibrous histiocytomas, a rare form of sarcoma. In this report, we discuss the case of a 15-year-old girl who initially presented with a histiocytic cerebral sarcoma that was treated with aggressive resection and chemotherapy. Three years later, the same patient developed increasing shortness of breath and was found to have a high-grade pleomorphic undifferentiated cardiac sarcoma that likely represents the primary tumour from which the cerebral lesion metastasised. This represents an extremely unique case; in 2010, a research group in Germany claimed the very first description of a true cardiac sarcoma with brain metastasis [1]. However, even as far back as 1960, there were three case reports [2] and more extensive sarcoma studies recently have revealed further cases [3]. Nevertheless, there have probably been less than 10 cases in the literature up until this point.

In Vitro Evaluation of the Effects of Multiple Oral Factors on Dental Implants Surfaces

Presence of metal ions and debris resulting from corrosion processes of dental implants in vivo can elicit adverse tissue reactions, possibly leading to peri-implant bone loss and eventually implant failure. This study hypothesized that the synergistic effects of bacterial biofilm and micromotion can cause corrosion of dental implants and release of metal ions in vivo. The goal is to simulate the oral environment where an implant will be exposed to a combination of acidic electrochemical environment and mechanical forces. Four conditions were developed to understand the individual and synergistic effects of mechanical forces and bacterial biofilm on the surface of dental implants; In condition 1, it was found that torsional forces during surgical insertion did not generate wear particle debris or metal ions. In condition 2, fatigue tests were performed in a wet environment to evaluate the effect of cyclic occlusal forces. The mechanical forces applied on the implants were able to cause implant fracture as well as surface corrosion features such as discoloration, delamination, and fatigue cracks. Immersion testing (condition 3) showed that bacteria (Streptococcus mutans) were able to create an acidic condition that triggered surface damage such as discoloration, rusting, and pitting. A novel testing setup was developed to understand the conjoint effects of micromotion and bacterial biofilm (condition 4). Surface damage initiated by acidic condition due to bacteria (condition 3), can be accelerated in tandem with mechanical forces through fretting-crevice corrosion. Permanent damage to surface layers can affect osseointegration and deposition of metal ions in the surrounding tissues can trigger inflammation.

Pulsed Radiation Therapy With Concurrent Cisplatin Results in Superior Tumor Growth Delay in a Head and Neck Squamous Cell Carcinoma Murine Model

PURPOSE

To assess the efficacy of 3-week schedules of low-dose pulsed radiation treatment (PRT) and standard radiation therapy (SRT), with concurrent cisplatin (CDDP) in a head and neck squamous cell carcinoma xenograft model.

METHODS AND MATERIALS

Subcutaneous UT-SCC-14 tumors were established in athymic NIH III HO female mice. A total of 30 Gy was administered as 2 Gy/d, 5 d/wk for 3 weeks, either by PRT (10 × 0.2 Gy/d, with a 3-minute break between each 0.2-Gy dose) or SRT (2 Gy/d, uninterrupted delivery) in combination with concurrent 2 mg/kg CDDP 3 times per week in the final 2 weeks of radiation therapy. Treatment-induced growth delays were defined from twice-weekly tumor volume measurements. Tumor hypoxia was assessed by (18)F-fluoromisonidazole positron emission tomography imaging, and calculated maximum standardized uptake values compared with tumor histology. Tumor vessel density and hypoxia were measured by quantitative immunohistochemistry. Normal tissues effects were evaluated in gut and skin.

RESULTS

Untreated tumors grew to 1000 mm(3) in 25.4 days (±1.2), compared with delays of 62.3 days (±3.5) for SRT + CDDP and 80.2 days (±5.0) for PRT + CDDP. Time to reach 2× pretreatment volume ranged from 8.2 days (±1.8) for untreated tumors to 67.1 days (±4.7) after PRT + CDDP. Significant differences in tumor growth delay were observed for SRT versus SRT + CDDP (P=.04), PRT versus PRT + CDDP (P=.035), and SRT + CDDP versus PRT + CDDP (P=.033), and for survival between PRT versus PRT + CDDP (P=.017) and SRT + CDDP versus PRT + CDDP (P=.008). Differences in tumor hypoxia were evident by (18)F-fluoromisonidazole positron emission tomography imaging between SRT and PRT (P=.025), although not with concurrent CDDP. Tumor vessel density differed between SRT + CDDP and PRT + CDDP (P=.011). No differences in normal tissue parameters were seen.

CONCLUSIONS

Concurrent CDDP was more effective in combination PRT than SRT at restricting tumor growth. Significant differences in tumor vascular density were evident between PRT and SRT, suggesting a preservation of vascular network with PRT.

Characterization of Cement Particles Found in Peri-implantitis-Affected Human Biopsy Specimens

PURPOSE

Peri-implantitis is a disease characterized by soft tissue inflammation and continued loss of supporting bone, which can result in implant failure. Peri-implantitis is a multifactorial disease, and one of its triggering factors may be the presence of excess cement in the soft tissues surrounding an implant. This descriptive study evaluated the composition of foreign particles from 36 human biopsy specimens with 19 specimens selected for analysis. The biopsy specimens were obtained from soft tissues affected by peri-implantitis around cement-retained implant crowns and compared with the elemental composition of commercial luting cement.

MATERIALS AND METHODS

Nineteen biopsy specimens were chosen for the comparison, and five test cements (TempBond, Telio, Premier Implant Cement, Intermediate Restorative Material, and Relyx) were analyzed using scanning electron microscopy equipped with energy dispersive x-ray spectroscopy. This enabled the identification of the chemical composition of foreign particles embedded in the tissue specimens and the composition of the five cements. Statistical analysis was conducted using classification trees to pair the particles present in each specimen with the known cements.

RESULTS

The particles in each biopsy specimen could be associated with one of the commercial cements with a level of probability ranging between .79 and 1. TempBond particles were found in one biopsy specimen, Telio particles in seven, Premier Implant Cement particles in four, Relyx particles in four, and Intermediate Restorative Material particles in three.

CONCLUSION

Particles found in human soft tissue biopsy specimens around implants affected by peri-implant disease were associated with five commercially available dental cements.

Foreign bodies associated with peri-implantitis human biopsies

BACKGROUND

Peri-implantitis is an inflammatory condition that can lead to implant loss. The aim of this descriptive retrospective study is to describe the histopathologic findings in soft tissue biopsies of implants with peri-implantitis.

METHODS

Thirty-six human peri-implantitis biopsies were analyzed using light microscopy (LM) and scanning electron microscopy (SEM). The composition of foreign materials found in the tissues was assessed using an energy dispersive x-ray spectrometer.

RESULTS

At the LM level, the inflammatory lesion of peri-implantitis was in most cases a mixture of subacute and chronic inflammation dominated by plasma cells. At the SEM level, radiopaque foreign bodies were identified in 34 of the 36 biopsies. The predominant foreign bodies found were titanium and dental cement. These foreign materials were surrounded by inflammatory cells.

CONCLUSIONS

At present, the exact mechanism for introduction of these materials and their role in peri-implantitis is unknown. Further research is warranted to determine their etiology and potential role in pathogenesis.

Use of ACE inhibitors in Fontan: Rational or irrational?

BACKGROUND

Despite a lack of evidence supporting the use of angiotensin-converting enzyme (ACE) inhibitors in patients with a Fontan circulation, their use is frequent. We decided to identify the rationale for ACE inhibitor therapy in patients within the Australia and New Zealand Fontan Registry.

METHODS

All patients in the Registry taking an ACE inhibitor at last follow up were identified, and a review of medical records was undertaken to determine the rationale for treatment initiation and reasons for treatment continuation or dose increase.

RESULTS

In 2015, 36% of the surviving patients in the Registry (462/1268) were taking an ACE inhibitor. Indications for initiation of therapy were ventricular systolic or diastolic dysfunction (29%), atrioventricular valve regurgitation (19%), preservation of normal ventricular function (7%), prolonged effusions at Fontan (6%), hypertension (6%), other (6%) and unknown (2%). No indication was stated in the remaining patients (25%). Those with hypoplastic left heart syndrome were more likely to be on an ACE inhibitor than those with an alternative primary morphology (70% vs 32%; p<0.001). Only 36% of the patients treated with an ACE inhibitor at last follow up (166/462) had an indication that would generally justify treatment in a two-ventricle circulation.

CONCLUSION

It is likely that the use of ACE inhibitors in patients with a Fontan circulation is excessive within our region. The coordination of prospective, multicentre studies and initiatives such as the Australia and New Zealand Fontan Registry will facilitate further investigations to guide treatment decisions in the growing Fontan population.

In Vitro Evaluation of Titanium Exfoliation During Simulated Surgical Insertion of Dental Implants

Dissolution of titanium wear particles in the oral environment, and their accumulation in the surrounding tissues have been associated with failure of dental implants (DI). The goal of this study is to investigate the effect of mechanical forces involved in surgical insertion of DI on surface wear and metal particle generation. It was hypothesized that mechanical factors associated with implant placement can lead to the generation of titanium particles in the oral environment. The testing methodology for surface evaluation employed simulated surgical insertion, followed by removal of DI in different densities of simulated bone material. Torsional forces were monitored for the insertion and removal of DI. The surface of the simulated bone materials was inspected with optical microscopy to detect traces of metallic particles that may have been generated during the procedure. Further characterization of the composition of powders collected from osteotomy cavities was conducted with powder X-ray diffraction. The results showed that the different densities of simulated bone material affected the torsional forces associated with implant insertion. However, the mechanical factors involved in the implant insertion/removal procedure did not generate wear particles, as confirmed by powder X-ray experiments.

Spectroscopic and microscopic investigation of the effects of bacteria on dental implant surfaces

The surface morphology and chemical composition of commercially pure titanium dental implants and healing abutments exposed in vitro or in vivo to oral bacteria were studied.

Detoxification of Implant Surfaces Affected by Peri-Implant Disease: An Overview of Non-surgical Methods

Objective:

The aim of this review is to summarize the findings of studies that have evaluated non-surgical approaches for detoxification of implant body surfaces in vitro and in vivo, and to evaluate clinical trials on the use of these methodologies for treating peri-implant disease.

Materials and methods:

A literature search was conducted using MEDLINE (Pubmed) from 1966 to 2013. In vitro and in vivo studies as well as clinical trials on non-surgical therapy were evaluated. The outcome variables were the ability of the therapeutic method to eliminate the biofilm and endotoxins from the implant surface, the changes in clinical parameters including probing depth, clinical attachment levels, bleeding on probing; radiographic bone fill and histological re-osseointegration.

Results:

From 134 articles found 35 were analyzed. The findings, advantages and disadvantages of using lasers as well as mechanical and chemical methods are discussed. Most of the in vivo and human studies used combination therapies which makes determining the efficacy of one specific method difficult. Most human studies are case series with short term longitudinal analysis without survival or failure reports.

Conclusion:

Complete elimination of the biofilms is difficult to achieve using these approaches. All therapies induce changes of the chemical and physical properties of the implant surface. Re-osseointegration may be difficult to achieve if not impossible without surgical access to ensure thorough debridement of the defect and detoxification of the implant surface. Combination protocols for non-surgical treatment of peri-implantitis in humans have shown some positive clinical results but long-term evaluation to evaluate the validity and reliability of the techniques is needed.

Endoscopic cyst-gastrostomy for pancreatic pseudocysts: refining the indications

BACKGROUND

Pseudocysts are a common consequence of acute pancreatitis and require intervention if symptomatic. Endoscopic management is emerging as a safe and effective alternative to surgery, although its use is not yet widespread.

METHODS

We describe our experience of 10 consecutive unselected patients who underwent endoscopic ultrasound-guided cyst-gastrostomy and stent insertion at a tertiary referral centre. Technical aspects of the procedure are detailed with accompanying photographs.

RESULTS

Six patients made an uneventful recovery. Four patients developed complications, of which one was successfully salvaged by endoscopy and three required surgery.

CONCLUSION

We discuss technical and patient factors which may have contributed to these complications in the context of current literature, and in particular, found that the presence of necrosis was associated with higher morbidity, both in our series and in others. In our experience, endoscopic ultrasound-guided cyst-gastrostomy is best employed in simple, mature pseudocysts without necrotic debris, and we recommend this procedure only after a detailed assessment of the pseudocyst in a specialist hepatobiliary unit.