Class II. – modifications for amalgam ⚫ Composed cavity ⚫ Slot ⚫ Large defects - restoration with the replacement of cusps Occlusal cavity Proximal cavity Slot is a cavity that is open on occlusal surface only in proximal ridge. Slot for amalgam ⚫ Access to the caries lesion - go through the enamel wall - breaking out of the enamel lamella - excavation of carious dentin lroubal@med.muni.cz 8 Pre op lroubal@med.muni.cz 9 Access to the cavity lroubal@med.muni.cz 10 Slot for amalgam ⚫ Autoretention - Grooves - Divergency towards gingiva - Convergency and divergency of axial walls in horizontal plane ⚫ Rule of the gingival wall Slot for amalgam ⚫ Rule of the gingival wall 90% angle towards the pulpal wall outer line beveled if in enamel horizontal groove Sedelmayer Sedelmayer J. Amalgám – zapomenuté řemeslo. Brno, 2000. Bažant V. Konservační zubní lékařství, SPN Praha,1962. Slot cavity ⚫ Limited on proximal ridge ⚫ Axial walls are divergent towards gingiva ⚫ The proximal box has a typical picture of fish tail ⚫ There are grooves: - One horizontal in gingival wall - Two vertical in axial walls Rules ⚫ Clear and sharp outlines ⚫ Autoretention - Cavities - pins - Grooves Large amalgam restoration - overlays ⚫ Preparation for adhesive materials ⚫ No extension for prevention (adhesion) ⚫ No grooves ⚫ No undercuts ⚫ Rounded box ⚫ Acid etching ⚫ Priming bonding ⚫ Placement of the material using matrices. Cavity for amalgam Cavity for composite Sectional matrices Matrice Separation ring Wedge 29 Steo I.: Pre - wedging Insertion of the ewdge before preparation Compression of gingiva Separation of teeth Protection of the tooth 30 Step 2: preparation Definujte zápatí – název prezentace nebo pracoviště31 Step 3: insertion of the matrix, wedge and separator (ring) ̶ Insertion of thematrix (0,5 mm below free gingiva) ̶ Insertion of the wedge from the vestibular or oral side ̶ Insertion of the separator Definujte zápatí – název prezentace nebo pracoviště32 Step 4 Zhotovení výplně Definujte zápatí – název prezentace nebo pracoviště33 Sedelmayer Alternative preparation - slot Tunnel preparation 1. Low caries risk 2. Proximal ridge without infrac 3. Good cooperation 4. D2 1. Loups or microscope 2. Miniinstruments 3. Dezinffection 4. GIC in capsules Success? Success 1. Nízké riziko sklonu k novým kazům 2. Spolupracující pacient 3. Okrajová lišta bez infrakcí 4. D2 – D3 1. Lupové brýle nebo mikroskop 2. Miniaturní instrumenty 3. Dezinfekce kavity 4. Jedině GIC v kapslích 5. BW post op Úspěch tunelu???? Úspěch tunelu???? Rules ⚫ Clear and sharp outlines ⚫ Autoretention - Cavities - pins - Grooves 59 60 Sedelmayer Adhesive slot preparation