Composites in posterior teeth All pit and fissure restorations. They are assigned in to three groups. R. on occlusal surface of premolars and molars R. in foramina coeca – usually on occlusal two thirds of the facial and lingual surfaces of molars. R.on lingual surface of maxillary incisors. T r v a n l i v o i s t Longevity of fillings Indications Moderate to large restorations Restorations that are not in highly aesthetics areas Restorations that have heavy occlusal contacts Restorations that cannot be well isolated Restorations that extend onto the root surface Foundations Abutmjent teeth for removable partioal dentures Temporary or caries control restorations. Contraindications Aesthetically prominent areas of posterior teeth Small moderate classes I. that can be well isolated Materials: Amalgam, composite. Amalgam: Pertinent material qualities and propeties Strength Longevity Ease of use Clinically proven sucess Clinical technique From the occlusal surface using the fissure bur (or diamond burs, see below). Outline Ideal outline includes all occlusal pits and fissures. If crista transversa od obliqua are no affected, it is recommended not to prepare them. Resistance principles Keep the facial and lingual margin extensionsas minimal as possible between the central groove and the cusp tips. Extending the outline to include fissures, thereby placing the margins on relatively smooth sopund tooth structure. Minimally extending into the marginal ridge without removing dentinal support. Eliminating a weak wall of enamel by joining teo outlines that come close together Enamel. – Nevel leave the enamel undermined All corners are round, the bottom smooth. Retention principles Prepare the box – the bottom is in dentin Undercuts can be prepared, the proximal ridges must not be weakened! Removal of carious, infected, dentin and remaining defective enamel. Spoon excavator or a slowly revolving , round carbid bur of appropriate size. Indications Aesthetically prominent areas of posterior teeth Small - moderate classes I. that can be well isolated Good level of oral hygiene is necessary Contraindications Moderate to large restorations Restorations that are not in highly aesthetics areas Restorations that have heavy occlusal contacts Restorations that cannot be well isolated Restorations that extend onto the root surface Abutment teeth for removable partioal dentures Temporary or caries control restorations. Materials: Amalgam, composite. Amalgam: Pertinent material qualities and propeties Strength Longevity Ease of use Clinically proven sucess Clinical technique From the occlusal surface using the fissure bur (or diamond burs) Outline Outline includes the caries lesion only Retention principles Prepare the box or deep dish – the bottom is in dentin Do not prepare any undercuts! Do not bevel enamel, finish the border with diamond bur inly. Removal of carious, infected, dentin and remaining defective enamel. Spoon excavator or a slowly revolving , round carbid bur of appropriate size. Polymerization shrinkage and its consequences Forces during polymerization Polymerization stress Polymerization – light curing composites - Mode of polymerization Phases - Pre-gel - G-point - Post -gel Monomer Light Polymerization Polymer Forces of polymerization shrinkage depend on - Composite material (content of filler) - Geometry of the cavity (C-factor) - Placement of the composite - Mode of polymerization Forces of polymerization shrinkage depend on Composite material (content of filler) High content of the filler causes bigger stress Flowable composites – low stress Forces of polymerization shrinkage depend on Geometry of the cavity (C-factor) Polymerization shrinkage C (configuration factor) explanation Polymerization shrinkage C (configuration factor) explanation Surface of adhesion/free surface of the filling 1/1 and less is optimal C - factor 5 2 1 C (configuration factor) explanation Postoperative sensitivity ditching marginal discoloration gap cracks Versluis 2000 Secondary caries Possible problems that can occure by improper handling Forces of polymerization shrinkage depend on - Placement of the composite: - Create the first layer thin, flowable can be used - Place th material in increments with respect of the C-factor of each layer Forces of polymerization shrinkage depend on - Composite material (content of filler) - Geometry of the cavity (C-factor) - Placement of the composite - Mode of polymerization 1 2 3 Placement of the material Correct Pre –gel Gel Post -gel Pre gel phase should be long – soft start Marginal adaptation depends on Placement of composite material Dry operating field Adhesive systems Flow materials - importance 1. Stress braker 2. Block out of the undercuts 3. Adaptation to the marginal walls 4. Aesthetic reasons 5. Protection of adhesives Temperovaný kompozit Adhesives Adhesive systems using acid etching technique Selfetching adhesive systems Adhesives Acid etching technique Etching Washing Priming Bonding Adhesives Selfetching adhesive systems Priming Bonding Adhesives Active and passive bonding Active – rubbing with microbrush Passive – without any rubbing Adhesive preparation in a fissure Adhesive preparation Preparation of enamel borders Preparation 45° Next to cusp 50-60°, Never cover the cusp Minikavity Otevírání fissur Class II. Class II. Main problems: Contact point Marginal adaptation Contact point Kompozitní výplň II. třídy Kompozitní výplň II. třídy Kompozitní výplň II. třídy Kompozitní výplň II. třídy Preparation 30 - 40° ? Marginal adpatation Margin in enamel Preparation do not bevel!!! Marginal adaptation In dentin Interproximal vertical borders Yes No Preparační technika Filling and Caries Excavation Proximal Preparation with SonicSys Final Preparation of Cavity Approximal Caries Approximal Caries Sedelmayer Alternative preparation - slot Tunnel preparation 1. Low caries risk 2. Proximal ridge without infraction 3. Good cooperation 4. D2 1. Loups or microscope 2. Miniinstruments 3. Dezinffection 4. GIC in capsules 5. BW post op Success? Success ART ART