[The nasopalatine duct cyst--epidemiology, diagnosis and therapy]

The nasopalatine duct cyst is the most frequent nonodontogenic cyst of the jaws. The cyst originates from epithelial remanents from the nasopalatine duct. The cells may be activated spontaneously during life, or are eventually stimulated by the irritating action of various agents (infection, etc.). Generally, patients present without clinical signs and symptoms. Therefore, the tentative diagnosis "nasopalatine duct cyst" is often based on a coincidental radiological finding on a routine panoramic view or occlusal radiograph. The definite diagnosis should be based on clinical, radiological and histopathologic findings. The therapy of nasopalatine duct cysts consists of an enucleation of the cystic tissue, only in rare cases a marsupialization needs to be performed. The present review of the literature presents and discusses the epidemiology, etiology, diagnostic work-up, differential diagnostic aspects, histopatholgy, and therapeutic strategies for nasopalatine duct cysts.

Aneurysmal bone cyst of the tuberculum articulare of the temporomandibular joint: a case report

A case is presented of a 14-year-old boy with aneurysmal bone cyst of the tuberculum articulare of the temporomandibular joint (TMJ). This disease rarely involves the skull, and involvement of temporal bone is even more rare. To our knowledge, only 22 cases have been reported in the literature. This is the first case of aneurysmal bone cyst of the tuberculum articulare of the TMJ described in the literature.

Lateral meniscal cyst causing common peroneal palsy

Lateral meniscal cysts are relatively common, but only in rare instances do they cause common peroneal nerve irritation. There are, we believe, no cases reported in which both the sensory and motor functions of the nerve have been compromised. We present a case of a lateral meniscal cyst that became palpable and led to symptoms of numbness and weakness in the distribution of the common peroneal nerve. The MRI findings were of an oblique tear of the lateral meniscus with an associated multiloculated meniscal cyst that coursed behind the biceps tendon before encroaching on the common peroneal nerve. Surgical resection confirmed the tract as located on the MRI and histology confirmed the mass to be a synovial cyst. Resection of the cyst and arthroscopic excision of the meniscal tear led to resolution of the symptoms in 3 months.

Surgical approach for synovial cyst of the atlantoaxial joint: a case report and review of the literature

STUDY DESIGN: Case report and review of the literature. OBJECTIVE: We describe the first case of a synovial cyst arising from pseudarthrosis of a previous dens fracture. The literature is reviewed and etiological, diagnostic, and therapeutic options of atlantoaxial cysts are discussed. SUMMARY OF BACKGROUND DATA: Symptomatic synovial cysts of the atlantoaxial joint are rare. To the authors' knowledge only 24 cases have been reported.A 60-year-old patient presented with bilateral hand numbness, quadrihyperreflexia, and gait deterioration. Magnetic resonance imaging of the cervical spine disclosed a cystic mass located at the transverse ligament of dens axis causing bulbomedullary compression. METHODS: Surgery was performed via transoral image guided approach. The ventral atlas arch, dens, transverse ligament, tectorial membrane, and the compressing cyst were removed, followed by a C0-C3 fusion. RESULTS: Two months postsurgery the patient recovered completely from the cervical myelopathy with transient remnant dysparesthesia of the finger tips. CONCLUSION: Magnetic resonance imaging findings are not specific enough to establish a preoperative diagnosis. Radical resection via image-guided transoral route followed by posterior fusion allows complete resection of the cystic lesion and results in excellent long-term decompression.

Comparative study of four retentive anchor systems for implant supported overdentures--retention force changes

OBJECTIVES: Wear of attachments leads to a loss of retention and potentially reduces the function of complete dentures. This study evaluated the retention force changes of different prefabricated attachment systems for implant-supported overdentures to estimate the wear constancy and applicability in clinical practice. METHODS: Four prefabricated attachment systems were tested [Group SG: retentive ball attachment (Straumann, Switzerland) with gold matrix, Group ST: retentive ball attachment (Straumann, Switzerland) with titanium spring matrix, Group IB: UNOR i-Ball with Ecco matrix (UNOR, Switzerland) and Group IMZ: IMZ-TwinPlus ball attachment with gold matrix (DENTSPLY Friadent, Germany)]. Ten samples of each system were subjected to 10,000 insertion-separation cycles. RESULTS: Results showed that all types of attachments showed wear, which led to a loss of retention force after an initial increase at the beginning of the wear simulation. Attachments with a plastic retention insert or gold matrices underwent the smallest changes in retention force. The titanium spring system showed the largest changes in retention force and a greater variation between the different cycles and specimen. This behaviour is probably caused by a large fitting tolerance of the titanium spring. CONCLUSIONS: Attachment systems which possess a male and female component of different material composition are preferable. They show smaller changes in the retention force. For retention force increase and wear compensation, an attachment system should be adjustable.

Comparison of drug retention rates and causes of drug discontinuation between anti-tumor necrosis factor agents in rheumatoid arthritis

OBJECTIVE: Tumor necrosis factor (TNF) inhibitors have revolutionized the treatment of severe rheumatoid arthritis (RA), yet drug discontinuation is common. The aim of this study was to compare treatment retention rates and specific causes of anti-TNF discontinuation in a population-based RA cohort. METHODS: All patients treated with etanercept, infliximab, or adalimumab within the Swiss Clinical Quality Management RA cohort between 1997 and 2006 were included in the study. Causes of treatment discontinuation were broadly categorized as adverse events (AEs) or nontoxic causes, and further subdivided into specific categories. Specific causes of treatment interruption were analyzed using a Cox proportional hazards model and adjusted for potential confounders. RESULTS: A total of 2,364 anti-TNF treatment courses met the inclusion criteria. Treatment discontinuation was reported 803 times: 309 with etanercept, 249 with infliximab, and 245 with adalimumab. Drug inefficacy represented the largest single cause of treatment discontinuation (55.8% of cases). The median time of receiving anti-TNF therapy was 37 months, but discontinuation rates differed between the 3 anti-TNF agents (P < 0.001), with shorter retention rates for infliximab (hazard ratio [HR] 1.24, 99% confidence interval [99% CI] 1.01-1.51). The specific causes of treatment discontinuation revealed an increased risk of AEs with infliximab (HR 1.4, 99% CI 1.003-1.96), mostly due to an increased risk of infusion or allergic reactions (HR 2.11, 99% CI 1.23-3.62). Other discontinuation causes were equally distributed between the anti-TNF agents. CONCLUSION: In this population, infliximab was associated with higher overall discontinuation rates compared with etanercept and adalimumab, which is mainly due to an increased risk of infusion or allergic reactions.

In situ fluoride retention and remineralization of incipient carious lesions after the application of different concentrations of fluoride

Limited information is available on the time-dependent or dosage-dependent cariostatic efficacy of highly concentrated fluoride compounds. This good clinical practice-conforming, double-blind, placebo-controlled, crossover in situ study tested the hypothesis that a 1.0% amine fluoride fluid is superior to a 0.5% amine fluoride fluid regarding fluoride retention and mineral change in initial caries enamel lesions over a period of 28 d. Fluoride retention was significantly higher after application of the two fluoride fluids compared with placebo but had decreased in both groups to similar levels after only 1 wk. Mineral gain was significantly higher for both verum groups compared with placebo. The use of 1% fluoride fluid resulted in significantly higher remineralization compared with the use of 0.5% fluoride fluid. For both fluoride fluids mineral gain followed a linear relationship with time during the experimental period, indicating a possible further uptake of mineral, even after 4 wk.

Association of gastroschisis and choledochal cyst

Two infants are described who presented in the neonatal period with a direct hyperbilirubinemia. This was initially presumed to be because of the diagnosis of gastroschisis and the prolonged use of parenteral nutrition. However, both infants were eventually found to have an associated choledochal cyst. The cases are a novel association not previously reported and should heighten the awareness that anatomical causes of a direct hyperbilirubinemia need to be ruled out in all neonates.

Pulse mTOR inhibitor treatment effectively controls cyst growth but leads to severe parenchymal and glomerular hypertrophy in rat polycystic kidney disease

The efficacy of mammalian target of rapamycin (mTOR) inhibitors is currently tested in patients affected by autosomal dominant polycystic kidney disease. Treatment with mTOR inhibitors has been associated with numerous side effects. However, the renal-specific effect of mTOR inhibitor treatment cessation in polycystic kidney disease is currently unknown. Therefore, we compared pulse and continuous everolimus treatment in Han:SPRD rats. Four-week-old male heterozygous polycystic and wild-type rats were administered everolimus or vehicle by gavage feeding for 5 wk, followed by 7 wk without treatment, or continuously for 12 wk. Cessation of everolimus did not result in the appearance of renal cysts up to 7 wk postwithdrawal despite the reemergence of S6 kinase activity coupled with an overall increase in cell proliferation. Pulse everolimus treatment resulted in striking noncystic renal parenchymal enlargement and glomerular hypertrophy that was not associated with compromised kidney function. Both treatment regimens ameliorated kidney function, preserved the glomerular-tubular connection, and reduced proteinuria. Pulse treatment at an early age delays cyst development but leads to striking glomerular and parenchymal hypertrophy. Our data might have an impact when long-term treatment using mTOR inhibitors in patients with autosomal dominant polycystic kidney disease is being considered.

Symptomatic retroperitoneal cyst: a diagnostic challenge

Retroperitoneal cystic masses pose an important diagnostic and therapeutic challenge. Simple drainage, internal or external, is usually not sufficient. We report a case of a large symptomatic retroperitoneal cyst and its management.