Class II. Defects affecting one or both proximal surfaces of posterior teeth. Location: Proximal surface in posterior area ̶ Proximal surface is caries danger area (below the contact point) – high plaque accumulation ̶ Interdental space is infilled with interdental palilla, that moves apically during the time and the space is open ̶ Dental caries originates below the contact point. lroubal@med.muni.cz 2 Class II. 3 Origin: Proximal surface below the contact point Propagation of dental caries from the occlusal surface lroubal@med.muni.cz 4 Symptoms ➢No symptoms ➢Increased sensitivity (cold, sweet) ➢Retention of food ➢Defect (carious lesion is open – the enamel is broken) ➢Bite sensitivity (when carious lesion is open) lroubal@med.muni.cz 5 Diagnosis ➢Visual changes of tooth structure (chalk white colour). ➢Transillumination (white light, or Diagno Cam). ➢Radiography lroubal@med.muni.cz 6 lroubal@med.muni.cz 7 lroubal@med.muni.cz 8 Bite wing projection lroubal@med.muni.cz 9 The sensor is placed in a special holder Central beam goes perpendiculary to the sensor as well as the long axis of the tooth And parallel with interdental septa DIAGNOCam Transillumination using infrared transillumination – near infrared NIR lroubal@med.muni.cz 14 lroubal@med.muni.cz 15 lroubal@med.muni.cz 16 lroubal@med.muni.cz 17 lroubal@med.muni.cz 18 Sedelmayer RTG vyšetření – Bite 4 stupňový grading lroubal@med.muni.cz 21 Preparation ➢Conventional preparation ➢Slot preparation ➢Large preparation – cusp(s) involved lroubal@med.muni.cz 22 Preparation - adhesive materials (composites, glass ionomers) ➢ Conventional preparation for composites ➢Adhesive slot ➢Tunnel preparation 23 Occlusal cavity Proximal cavity - box Conventional preparation amalgam lroubal@med.muni.cz 24 Pulpal wallsAxial wall Gingival wall Isthmus 25 MO, OD: one proximal surface affected – mesio occlusal distoocclusal MOD: mesiodistoocclusal lroubal@med.muni.cz 26 Access to the cavity From the occlusal surface Through the undermined enamel Separation using wooden wedges is useful 27 Pre op lroubal@med.muni.cz 28 Access to the cavity lroubal@med.muni.cz 29 Breaking the thin enamel layer out of the cavit Wooden wedge lroubal@med.muni.cz 30 ➢ Remove of the gingiva that grows into the cavity lroubal@med.muni.cz 31 Cavosurface margin and extention for prevention Proximal box: Vestibullary and orally – axial walls (the border between the oral/vestibular and proximal surface. Below the free gingiva (0,5 mm) Occlusal Class I. lroubal@med.muni.cz 32 Study the contact area (contact point): The axial walls (cavosurface margins) are approx. o 0,5 mm vestibulary and orally Over this area. The contact of the treated tooth is made of the restorative materials. Axial walls Gingival wall is parallel with the cementoenamel junction and it is situated appr. 0,5 mm below free gingiva. lroubal@med.muni.cz 33 v American rule Tangents from the middle of treated tooth to the next tooth – where these cross the treated Tooth there are borders of the preparation lroubal@med.muni.cz 34 Retention - macroretention for amalgam ➢Occlusal cavity ➢ Undercuts ➢Grooves 35 Axiální stěny divergují gingiválně Rýhy a zářezy Autoretention Grooves Proximal cavity – box Slight divergency of axial walls Gingival wall follows the cementoenamel junction Gingival wall is below free gingiva For amalgam only ! lroubal@med.muni.cz 36 Retention - microretention for composite ➢Removal of the aprismatic enamel ➢Bevel enamel on axual walls and outer edge of the gingival wall ➢Do not bevel the enamel in the occlusal cavity lroubal@med.muni.cz 37 Resistance ➢No undermined enamel ➢No sharp edges ➢Isthmus is 1/3 – 1/4 intercuspidal distance ➢ Angle between axial and gingival wall: 90°, or 85° ➢Width of gingival wall is 1 mm at least ➢ Thickness of the filling 2 – 4 mm (4mm if cusp replacing) 38 Cavosurface angle Gingival wall Isthmus 39 Excavation of carious dentin Rounded bur (Caries Detector, Kuraray, Japonsko; Caries Marker, VOCO,Německo) lroubal@med.muni.cz 40 Finishing of the walls of the cavity ➢ Red coded diamond bur ➢Chisel on the gingival wall (if in enamel) 41 42 lroubal@med.muni.cz 43 lroubal@med.muni.cz 44 Final check ➢Goog light, miror For cavities where more than one wall is missing we need matrix ̶ Matrix is a small tool that replace a missing wall (walls) and enable to gice the filling the proper contour Definujte zápatí – název prezentace nebo pracoviště45 lroubal@med.muni.cz 46 Pulpal wall Axial wall Gingival wall Isthmus lroubal@med.muni.cz 47 Matrix ➢Matrix primarily is used when a proximal surface is to be restored The objectives: - Provide proper contact - Provide proper contour - Confine the restorative material - Reduce the amount of excess materiál In some cases id important for good setting of the material lroubal@med.muni.cz 48 Matrices for II.nd class Circular and sectional matrices ➢Circular matrices round the tooth They are used in combination with the matrix retainer. ➢Sectional matrices do not round the tooth, the proximal surface only. lroubal@med.muni.cz 49 lroubal@med.muni.cz 50 lroubal@med.muni.cz 51 Wedges ➢ Wooden wedges - tighten the matrix band - compress the gingiva - separate the teeth lroubal@med.muni.cz 52 Wedging ➢Slip the matrix band over the tooth (apical to the gingiva margin – 0,5, - 1 mm) ➢Tighten the matrix, check it with probe ➢Place a wedge ➢Turn the retainer ¼ counterclockwise ➢ Contour the band lroubal@med.muni.cz 61 Sapin lroubal@med.muni.cz 62 Discoid-cleoid Composites - indication ̶ Small – moderate cavities - Good level of oral hygiene - No heavy occlusal stress - Dry operating field Preparation for adhesive materials – composites ̶ Not too bug extension for prevention (adhesion) ̶ No grooves ̶ No undercuts ̶ Rounded box ̶ Bevel the axial walls and the outer edge od the gingival wall ̶ Small isolated cavities are possible Cavity for amalgam Cavity for composite Bevel on the gingival wall Preparation do not bevel!!! If out of enamel Bevel of enamel on axial walls Yes No Amalgam Composite material Matrices for composites in class II. ̶ Matrix band + matrix retainer (circular matrices – see above) ̶ Segmental matrix (sectional matrices) + separator Forceps for handling Sectional matrices Sequence of operation ̶ Preparation ̶ Bevel the enamel on axial walls and outer edge of gingival wall (if located in enamel) ̶ Placement of the matrix ̶ Adhesive procedure (acid etching, washing, priming and bonding) ̶ Placement of the composite materiál layer by layer ̶ Curing ̶ Finishing and polishing 80 93 Sedelmayer Alternative preparation – adhesive slot Fissures are not involved Tunnel preparation