[One-year results after Cypass implantation]. / 1-Jahres-Ergebnisse nach Cypass-Implantation.

BACKGROUND: The Cypass Microstent (Transcend Medical, Menlo Park, CA, USA) is a biocompatible polyamide implant that is implanted in the suprachoroidal space and improves the flow of the aqueous humour via the uveoscleral pathway. MATERIAL AND METHODS: In a retrospective clinical study 162 patients (220 eyes) with an average age of 71.8 (±14.2) years with a mild to moderate glaucoma were treated with a Cypass implant. In the study three groups of patients (group 1, group 2 and group 3) were formed. Group 1 included patients with pseudophakia who received a Cypass implant, group 2 consisted of patients with a Cypass implant combined with phacoemulsification and implantation of an intraocular lens (Phako/HKL) and group 3 included patients who had had multiple eye surgeries before the Cypass implantation. The follow-up period of the study was 1 year. RESULTS: The mean preoperative intraocular pressure (IOP) in group 1 was 20.0 (±8.4) mm Hg and in group 2 was 20.8 (±8.7) mm Hg. The mean IOP fell to 17.7 (±7.1) mm Hg in group 1 (pressure reduction: 11.7%, p < 0.05) and in group 2 to 18.0 (±7.0) mm Hg (pressure reduction: 13.4%, p > 0.05) 12 months postoperatively. The decrease of IOP in group 3 after 1 year was 11.2%. In 20.5% of the cases (45 eyes), additional operative pressure reducing interventions was performed because the target pressure was not achieved. CONCLUSION: After 1 year patients in group 2 showed a significantly similar reduction in pressure as group 1. Additionally, both groups showed a reduction in the number of locally applied antiglaucoma agents. The reduction of the IOP in group 3 was not significant after 12 months, in contrast to the other two groups.

Micro-hardness and mineral loss of enamel lesions after infiltration with various resins: influence of infiltrant composition and application frequency in vitro.

OBJECTIVES: The aim of this in vitro study was to evaluate the influence of infiltrant composition and application frequency on micro-hardness and lesion progression after resin infiltration of artificial enamel lesions. METHODS: In each of 100 bovine enamel samples, three artificial caries lesions were created (pH=4.95, 50 days). After etching two of the lesions (37% phosphoric acid) specimens were randomly allocated to five infiltrants (four experimental infiltrants with different monomer and solvent compositions and penetration coefficients, and one commercial infiltrant [Icon, DMG]). Lesions were then infiltrated and light-cured, and infiltration repeated afterwards for one of the lesions. Infiltrated samples were cut into halves, with one half being demineralised for further 50 days. Micro-hardness (VHN) and integrated mineral loss (ΔZ) were evaluated at baseline and after second demineralisation. Repeated measures ANOVA and paired t-tests were used to analyse influence of material composition and application frequency on micro-hardness and lesion progression (integrated mineral loss difference ΔΔZ). RESULTS: Resin infiltration significantly increased micro-hardness and reduced lesion progression compared to untreated artificial lesions (p<0.05, t-test). Neither micro-hardness nor lesion progression were significantly influenced by material composition (p>0.05, ANOVA). In contrast, twice application resulted in significantly increased micro-hardness and demineralisation resistance of infiltrated lesions (p<0.05, ANOVA). CONCLUSION: Resin infiltration significantly improves micro-hardness and demineralisation resistance of enamel lesions; these effects are significantly enhanced if resins are applied twice. Experimental resins did not outperform the commercial infiltrant. CLINICAL SIGNIFICANCE: This in vitro study demonstrated that resin infiltration significantly increases both micro-hardness and demineralisation resistance of enamel caries lesions. Twice application of the infiltrant seems to increase these effects. In contrast, the composition of the infiltrant had no significant influence on investigated parameters.