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Purpose: This study evaluated the influence of a soft-start light-curing exposure on polymerization shrinkage stress and marginal integrity of adhesive restorations., Materials and Methods: Six resin-based composites (Pertac II, Tetric Ceram, Definite, Surefil, Solitaire, and Visio-Molar) were adhesively bonded to a cylindrical cavity (n = 9 per material/light) in a photoelastic material. Visible light-curing was applied using either the standard polymerization mode (800 mW/cm2 exposure duration 40 s) of the curing light (Elipar TriLight, 3M ESPE) or the exponential mode from the same device (ramp-curing: 150 mW/cm2 to 800 mW/cm2 within the first 15 s of a total curing time of 40 s). Polymerization stress was calculated at 5 minutes, 1 hour, and 24 hours postexposure from the second-order isochromatic curves obtained from photoelastic images (Matrox-Inspector). Two standardized Class V preparations were made each on the facial and lingual surfaces of 80 extracted human molars and premolars. Resin restorative systems (Pertac II/EBS Multi, Tetric Ceram/Syntac, Definite/Etch&Prime 3.0, and Surefil/Prime & Bond 2.1) were exposed using both light exposure modes (n = 20). Marginal dye penetration (2% methylene blue) was investigated separately for enamel and cementum margins after thermocycling. To obtain information on equivalent depth of cure, relative surface hardness measurements were performed on resin samples of the same material at the top surface and at 1.5 mm and 3.0 mm thickness (Zwick 3212, 10 N)., Results: A significant (p < .01) reduction in polymerization stress of 7.1% for Pertac II, 4.1% for Tetric Ceram, 3.6% for Definite, 3.7% for Surefil, and 6.2% for Solitaire was observed when using the exponential mode as opposed to the standard. A significant (p = .04) reduction of marginal dye penetration was found only for Pertac II/EBS Multi at the cementum margins when the soft-start polymerization was used. For the sample thickness of 3 mm, a significant higher relative bottom to top surface ratio in favor of the standard exposure mode was found (p = .001)., Clinical Significance: Depending on the restorative material, soft-start polymerization may lead to a significant reduction in marginal microleakage of adhesive Class V restorations. This effect might be attributable to a significantly lower polymerization stress, as seen from photoelastic analysis, and/or a decrease in the degree of conversion, as deducted from surface hardness ratios. However, the effect of soft-start curing mode depends on the material itself, with the most effective response from hybrid resin-based composites.

Outcome predictors were analyzed in 45 infants and children with cerebrovascular disorders (CVD), based on clinical features and radiological correlates. The clinical features at presentation could be categorized into three major groups: (1) generalized: alteration of consciousness with or without seizures--24 patients (54%); (2) focal: acute hemiplegia or monoplegia with or without focal seizures--18 patients (40%); (3) cerebellar disturbances--3 patients (6%). The underlying etiology was detected in 80% of children. Thirty-seven patients (82%) survived the initial debilitating event, of whom 11 (29.7%) recovered completely and the rest had either motor or cognitive handicaps during an average follow-up period of 4.2 years (range 1.5-11 years). A head CT performed in all children revealed ischemic infarction in 29 patients (64.4%), while the others had hemorrhagic infarction. Of those with an initial generalized neurological presentation, as many as 50% had multi-focal lesions on CT. All children with focal neurological findings had a solitary localized lesion on CT, mainly in the distribution of the middle cerebral artery. Statistical analysis for outcome prediction showed that the following variables were associated with increased risk of immediate death: (1) hemorrhagic infarction demonstrated by brain CT (p = 0.031); (2) patients who presented with a generalized neurological disorder, namely alteration of consciousness, with or without seizures (p = 0.036). No other clinical or laboratory variables were predictive of imminent death, motor or cognitive handicaps. These may therefore serve as outcome predictors of stroke in the pediatric age group.

Three mentally retarded children with severe self-inflicted ocular injuries are presented. All three suffered from severe ocular injuries including retinal detachment resulting in progressive visual loss and even blindness. Self-inflicted injuries to the eyes, including self enucleation, is an extremely uncommon form of behavior, rarely encountered by pediatricians. The risk of ocular morbidity is high if the diagnosis is overlooked. Technical advances in ophthalmology permit much improvement in some formerly hopeless cases of ocular self-mutilation, but there is still no accurate method to repair destroyed retinal or nervous tissue. Early identification of patients at risk of ocular self-mutilation is essential in order to prevent or minimize such severe ocular injuries.

Although acute transverse myelitis is a rare complication of mumps, it is relatively well documented. We describe a child who developed mumps associated acute transverse myelitis and who subsequently recovered completely. To our knowledge, only 13 cases have been reported in children. This case is compared with 13 previously reported patients.