Restorative dentistry I. Mistakes, preparation trauma, postoper.sensitivity 1. Periodontal diseases related to restorative treatment 2. Management of deep caries 3. Preparation trauma 4. Postoperative sensitivity Prevention ̶ Gentle interrupted preparation ̶ Sharp instruments, well centered ̶ Sufficient watercooling by using highspeed rpm (50ml/min) ̶ The biggest preparation instruments for the excavation of carious dentin Definujte zápatí – název prezentace nebo pracoviště2 Restorative dentistry III. 5 th lecture 1. Periodontal diseases related to restorative treatment Mistakes of making filling can cause periodontal diseases ̶ Reconstruction of the contact point: ̶ Contact point – contact area! ̶ The space below the contact area is a caries danger area – plaque accumulation! ̶ The interdental papilla is retracting during ageing – interdental oral hygiene is important! Definujte zápatí – název prezentace nebo pracoviště4 Mistakes of making filling can cause periodontal diseases ̶ Reconstruction of the contact area is very important! ̶ Remember – by reconstruction the contact area remember that: ̶ Contact area is made of the filling material only. The axial walls are situated 0,5mm from the natural contact area. ̶ By reconstruction is important to study the contact area! Definujte zápatí – název prezentace nebo pracoviště5 Definujte zápatí – název prezentace nebo pracoviště6 Clinical conseqences of the most common mistakes – the contact point is missing The contact area is missing Retention of food Plaque accumulation Inflammation Bone resorption Periodontal pocket Definujte zápatí – název prezentace nebo pracoviště7 Definujte zápatí – název prezentace nebo pracoviště8 Bad contour, overhang Contact area too narrow Definujte zápatí – název prezentace nebo pracoviště9 Clinical conseqences of the most common mistakes – the overhang Retention of food Plaque accumulation Inflammation Bone resorption Periodontal pocket Mechanic irrtiation Secondary caries Definujte zápatí – název prezentace nebo pracoviště10 Clinical conseqences of the the other mistakes – trauma Separation ring Matrix band Preparation instruments Wedges Necrotizing agent – necrosis of papilla od bone. Definujte zápatí – název prezentace nebo pracoviště11 Management of deep caries Caries pulpae proxima ̶ Dental caries next to dental pulp ̶ Dentin between the lesion and the pulp (can be decalcified) Caries pulpae proxima only small part of the cavity is deep ̶ Indirect pulp capping Caries next to dental pulp (caries pulpae proxima). Carious dentin is possible to remove almost completely. Decay is deep in small region. Appr 1 mm2 carious dentin can be left. Kalciumhydroxide cement,permanent filling Alternativs: MTA, Biodentine Formation of tertiary dentine. Large caries pulpae proxima or caries ad pulpam penetrans ̶ Intermitent excavation Large dental caries spreading towards dental pulp. Big amount of carious dentine. High risk of perforation Suspension of calcium hydroxide, temporary filling for 6 weeks. Dessication of soft dentine, formation of tertiary dentine. Permanent filling follows 16 Intermitent excavation Pulpotomy Deep caries – D4 x ray ̶ Caries pulpae proxima ̶ Caries ad pulpam penetrans Definujte zápatí – název prezentace nebo pracoviště17 Caries pulpae proxima ̶ Dentine between the caries lesion and dental pulp ̶ No symptoms ̶ Indirect pulp therapy: indirect pulp capping Calcium hydroxide cement, premanent filling. Definujte zápatí – název prezentace nebo pracoviště18 Caries ad pulpam penetrans ̶ No symptoms ̶ Symtomatic (pulpitis?) Definujte zápatí – název prezentace nebo pracoviště19 Caries ad pulpam penetrans ̶ No symptoms Vitaliy +: 1. Indirect pulp capping (intermittent excavation) 2. Pulpotomy (aseptic approach, rubber dam) Definujte zápatí – název prezentace nebo pracoviště20 Caries ad pulpam penetrans ̶ Symptoms Vitaliy +: 1. Pulpotomy (aseptic approach, rubber dam) - Partial - Coronal - Deep Definujte zápatí – název prezentace nebo pracoviště21 Caries ad pulpam penetrans ̶ No symptoms Vitality - : Endodontic treatment Definujte zápatí – název prezentace nebo pracoviště22 Postoperative sensitivity ̶ Pain occuring after the placement of composite restoration ̶ Studies have reported the frequency of postoperativr sensitivity to be low 5% and high 30% Definujte zápatí – název prezentace nebo pracoviště23 Postoperative sensitivity - reasons ̶ Polymerization shrinkage ̶ Marginal gap ̶ Suboptimal adhesion ̶ Inadequate polymerization ̶ Unvfavourable C- factor and residual dentin thickness ̶ Pre-existing tooth relatefd factors, such as cracks Definujte zápatí – název prezentace nebo pracoviště24 Postoperative sensitivity ditching marginal discoloration gap cracks Versluis 2000 Secondary caries Postoperative sensitivity - reasons ̶ Polymerization shrinkage and polymerization stress - Gap in dentin - Cracs in enamel - Cuspal deflection – enamel crazes or fracture lines Cracs may increase flexure of tooth structure under occlusal loading or become an avenue for bacterial ingress. Moreover dentinal fluid in association with the cuspal deflection can potentially induce post op sensitivity depending on the rate and direction of fluid movement. Definujte zápatí – název prezentace nebo pracoviště26 Postoperative sensitivity ̶ The risk and the intensity of postoperative sensitivity is not associated with the filling matarials. (Silorane, bulkfill – no effect) Definujte zápatí – název prezentace nebo pracoviště27 Postoperative sensitivity - reasons - Marginal gap Marginal gap is a potential site for bacterial ingress, a portal for fluid exchange leading to the movement of dentinal fluid – post op sensitivity, marginal discoloration, secondary caries Definujte zápatí – název prezentace nebo pracoviště28 Postoperative sensitivity - reasons ̶ Polymerization shrinkage and polymerization stress - Gap in dentin - Cracs in enamel - Cuspal deflection – enamel crazes or fracture lines Cracs may increase flexure of tooth structure under occlusal loading or become an avenue for bacterial ingress. Moreover dentinal fluid in association with the cuspal deflection can potentially induce post op sensitivity depending on the rate and direction of fluid movement. Definujte zápatí – název prezentace nebo pracoviště29 Postoperative sensitivity - reasons - Factors affecting the marginal adaptation - Contamination - Inadeguate bonding application - C- factor - Absence of enamel at the restorative margin Definujte zápatí – název prezentace nebo pracoviště30 Postoperative sensitivity - reasons - Factors affecting the marginal adaptation - Enamel still remains the most favorable substrate for bonding, long term bond longevity in dentine remains questionable due to hydrolytic degradation of the hybrid layer components. Definujte zápatí – název prezentace nebo pracoviště31 Postoperative sensitivity - reasons - Suboptimal adhesion A gap forms beneath the restoration and fills with dentinal fluid, sudden movement of dentinal fluid causes pain. Definujte zápatí – název prezentace nebo pracoviště32 Postoperative sensitivity - reasons -_ Suboptimal adhesion The gap formation - A void in the composite materiál being placed on the floor of the cavity - Pulling away of composite from pulpal wall due to shrinkage stress - Gap in the hybrid layer due to insufficient resin infiltration resulting in formation of hybroid layer. Definujte zápatí – název prezentace nebo pracoviště33 Postoperative sensitivity - reasons ̶ Suboptimal adhesion Flowable at the bottom? Inadequate permeation of the demineralized dentinduring the restorative procedure is a significant contributor to postoperative sensitivity. Selfetching adhesive systems? No significant association between the bonding stratégy with risk and intensity od postoperative sensitivity.Definujte zápatí – název prezentace nebo pracoviště34 Postoperative sensitivity - reasons ̶ Suboptimal adhesion No significant association between the bonding strategy with risk and intensity od postoperative sensitivity. Definujte zápatí – název prezentace nebo pracoviště35 Flowables - importance 1. Excellent marginal adaptation 2. Protection of the adhesive 3. Elastic layer ? Postoperative sensitivity - reasons ̶ Inadequate polymerization Composites are relatively flexible in comparison to the stiffness of tooth enamel (modulus elasticity) The flexure of composite restorations in relation to the tooth can produce pressure changes in the dentinal tubular fluid and subsequent fluid movement – can provoke pain on chewing. Definujte zápatí – název prezentace nebo pracoviště37 Postoperative sensitivity - reasons ̶ Inadequate polymerization ̶ When adequate placement – the biting sensitivity is rare but ̶ If the degree of polymerization of the materiál is not in the acceptable limits – it leads to soggy bottom phenomenon. Bulk fill materials x incermental techniques showed no significant difference in the occurence of reported post op sensitivity. Definujte zápatí – název prezentace nebo pracoviště38 Postoperative sensitivity - reasons ̶ Inadequate polymerization Biological consequences: The process of polymerization is not complete in the set materiál. 25 – 50% od the monomer double bonds remain unreacted and this monomer has the potential to irritate the pulp. Adequate polymerization is important! Definujte zápatí – název prezentace nebo pracoviště39 Postoperative sensitivity - reasons ̶ Unvfavourable C- factor and residual dentin thickness High C- factor – higher risk of gap fprmation as well as cracs (see the explanation in the first lecture) Remaining dentin thickness: Increased cavity depth and reduced dentine thickness – higher risk of postoperative sensitivity. Base of GIC? Definujte zápatí – název prezentace nebo pracoviště40 Postoperative sensitivity - reasons ̶ Pre-existing tooth relatefd factors, such as cracks Definujte zápatí – název prezentace nebo pracoviště41 Postoperative sensitivity - reasons ̶ Pre-existing tooth relatefd factors, such as cracks Restoration of a tooth with an unidentified crack can result in symptoms that can be confused with postoperative sensitivity. Definujte zápatí – název prezentace nebo pracoviště42 Postoperative sensitivity - reasons ̶ Pre-existing tooth relatefd factors, such as cracks ̶ Cracs can developed in the tooth structure due to masticatory insults over the period of time. Cavities with an intercuspal width exceeding one quarter are at increased risk of crack development. ̶ Consider cuspal coverage! Definujte zápatí – název prezentace nebo pracoviště43 2 mm Postoperative sensitivity prevention ̶ Correct indication ̶ Excellent isolation ̶ Careful investigation using magnification and illumination ̶ Proper etching ̶ Proper drying ̶ Proper curing Definujte zápatí – název prezentace nebo pracoviště46 Postoperative sensitivity strategy ̶ Perfect investigation - Check occlusion - Check margins (sealing?) - Check tooth structure If some reason is found: remove it Definujte zápatí – název prezentace nebo pracoviště47 Postoperative sensitivity strategy - If the symptoms are getting worse - remove the filling, check the tooth structure carefully, - use calcium hydroxide with the temporary filling material or bioactive materiál (Biodentine), - Make a new filling. Definujte zápatí – název prezentace nebo pracoviště48 Definujte zápatí – název prezentace nebo pracoviště49 Preparation techniques and their clinical consequences – preparation trauma Preparation Power driven - Rotary - Alternative Hand - Excavator - Chisel Definujte zápatí – název prezentace nebo pracoviště50 Preparation techniques ̶ Pressure – max hand preparation – risk of excavators ̶ Vibrations ̶ Heat – due to friction - increases with rpm (turbine max) Definujte zápatí – název prezentace nebo pracoviště51 Consequences in enamel, dentin, cementum ̶ Rotary preparation with high speed handpiece, turbine: ̶ Enamel :shattered borders, cracs. Prevention: gentle interrupted preparation, water cooling. ̶ Dentine: burnt areas, denaturation of protein. ̶ Dental pulp: aspiration of odontoblasts into dentine tubules, hyperaemia, infiltration, inflammation. Definujte zápatí – název prezentace nebo pracoviště52