Materials Used in Endodontics PDF

MATERIALS USED IN ENDODONTICS Dr. Ishara Gamage Consultant in Restorative Dentistry TH - Kalutara  What is endodontics? Discipline of dentistry that prevents or treats diseases of the dental pulp and the periradicular tissues Proc...

MATERIALS USED IN ENDODONTICS Dr. Ishara Gamage Consultant in Restorative Dentistry TH - Kalutara  What is endodontics? Discipline of dentistry that prevents or treats diseases of the dental pulp and the periradicular tissues Procedures: Aim to save the pulp in a viable state  Pulp capping – direct / indirect and to re-establish the tooth as a fully  Pulpotomy functioning entity  Pulpectomy/ pulp extirpation (Root canal treatment)  Regenerative Endodontics  Pulp capping – Indirect Deepest carious dentine is not removed to avoid pulp exposure Materials used  Calcium Hydroxide  Calcium silicate materials (MTA / Biodentine / Resin modified Calcium Silicate (TheraCalLC)  Adhesive resins / Dentine bonding agents  Glass Ionomer cement / RM- GIC  Pulp capping – Direct When the pulp is exposed – carious / mechanical Materials used  Calcium Hydroxide  Calcium silicate materials (MTA / Biodentine / Resin modified Calcium Silicate (TheraCalLC)  Ideal properties of a pulp capping agent Biocompatible Maintain pulp vitality Stimulate reparative dentine formation Able to provides a bacterial seal – bacteriostatic / bactericidal Adhere well to dentine and restorative material Resists the forces under restoration for life time Sterile Radiopaque  Pulpotomy – partial / Complete Complete / partial removal of inflamed coronal pulp Placement of a medicament to fix, mummify or stimulate repair of the remaining pulp Materials used 3 groups based on their mechanism of action  Devitalization / Fixation– Formocresol, electrosurgery and laser  Preservative / minimal devitalization – Ferric sulfate and Gluteraldehyde  Regeneration / Repair - Calcium Hydroxide / Calcium silicate materials  Ideal properties of a pulpotomy medicament Non irritant to periapical tissues Antimicrobial Stable in solution Should not stain tooth structure Should not be antigenic Should not interfere with periapical healing Less expensive Easy to use Non toxic  Formocresol Widely used in primary tooth pulpotomies First introduced by Buckley in 1904 Introduced as a pulpotomy agent in 1930 by Sweet Divers formulations available Buckley’s formula composed of  19% Formaldehyde – as an alkylating agent  35% Tricresol – protein coagulating phenolic substance  15% Glycerin Prevent formaldehyde from polymerizing to para formaldehyde  31% water 1:5 Diluted solution of Buckley’s formocresol is used  3 parts of glycerin (90ml) +1 part of distilled water (30 ml) + 1 part of formocresol (30 ml) = 1:5 concentration  Formocresol – Mode of action Formaldehyde component – protein binding Tricresol – Lipophilic/ lipid solvent property Aldehyde group Tricresol Bacterial Pulpal tissue proteins (cellular Bacterial cell membrane Remaining pulpal tissue proteins – proteins and enzymes) – lysis of bacterial cells – destroy cellular strongly Inhibit enzymes involved in intergrity, potentiating bactericidal inflammatory process effects of Fomaldehyde Completely fix /mummify (allows deeper tissue all residual pulpal tissues fixation by Formaldeyde and necrotic material in the component) root canal Prevent autolysis of tissues  Properties of Formocresol Stable at room temperature Long shelf life Exhibits bactericidal and devitalizing effects Less technique sensitive and easy to apply High success rate  Disadvantages of Formocresol Local and systemic absorption of Formaldehyde-  Half life 1-2 minutes – rapidly cleared from body fluids Allergic and immunogenic effects – Formaldeyde Carcinogenicity - due to the presence of Formaldehyde the International agency for research on cancer has concluded that chronic exposure to high levels of formaldeyde cause nasopharyngeal cancer in humans. Mutagenicity and genotoxicity – due to cresol on mammalian cells Risk of tissue damage (mucosal burns, ulcerations etc) if contact with nearby soft tissues  Gluteraldehyde Used in primary tooth pulpotomy Pulp preservative / minimal devitalization Colourless oily liquid Recommended concentration is 2% Mode of action  Similar to Formocresol  Has 2 functional aldehyde groups (bifunctional molecule) which fix protein by affecting the free amino groups  Gluteraldehyde Advantages disadvantages Superior fixative properties to formocresol Short shelf life ( 1 week) Better antibacterial activity Unstable in solution - Need Self limiting penetration – initial zone of to be freshly prepared fixation does not migrate apically thus more vital tissue remains in the apical portion of the Low levels of clinical success canal than formocresol Do not diffuse out of the tooth – no systemic effects Potentially low antigenicity , low toxicity No Cresol component and its toxic effects  Ferric sulphate Widely used in dentistry as a haemostatic agent ( Astringedent) Used in primary tooth pulpotomy Recommended concentration – 15.5% Mode of action  Ferric and sulfate ions within the acidic pH of the solution reacts with blood / pulpal tissues forming a iron – protein complex  The agglutinated proteins form plugs over the cut vessels / capillary orifices blocking them mechanically, producing hemostasis (block capillary blood flow and initiate hemostasis without clot formation)  Preservation- maintains vital tissue with no induction of reparative dentine  Ferric sulphate Disadvantages Advantages Inexpensive Calcification of root canals No systemic absorption Hazardous, corrosive liquid which has potential to cause severe injury Decrease inflammation Decomposes to form sulphuric acid No toxicity that can cause superficial tissue burns if it is not confined to the pulpotomy site  Regenerative / reparative materials in pulpotomy Calcium Silicate materials (MTA / Biodentine) – used in both primary and permanent teeth pulpotomy Calcium Hydroxide – Permanent teeth pulpotomy Ability to induce hard tissue formation  Pulpectomy / Root canal Treatment Removal of entire pulp to eliminate / prevent pulp and periradicular infection Accomplished by disinfecting, cleaning and shaping of the root canal Obturation of the entire root canal with a biologically acceptable material  Materials used in Root canal treatment 1. Irrigants and lubricants : used during canal preparation / cleaning and shaping 2. Intracanal medicaments : materials placed within the canal between clinical visits to maintain the canal in a disinfectant state 3. Obturating materials : the bulk fill material and sealant used during canal obturation 4. Used during endodontic surgery and repair of internal damage within the root canal system  Irrigants and lubricants Why irrigants are used?  Flush the debris out of the prepared area  Disinfect the root canal Properties of an ideal root canal irrigant  Able to dissolve / disrupt tissue and debris in the canal (both organic and inorganic) and inactivate endotoxins  Able to disinfect the canal system  Offer long term antibacterial effect (substantivity)  Low surface tension (to allow penetration into inaccessible areas)  Able to lubricate instruments in the canal  Able to remove the smear layer from the surface/ root canal walls  No adverse effects on the dentine or the sealing ability of filling materials  Irrigants and lubricants Properties of an ideal root canal irrigant ctd.. Non toxic Non antigenic Non carcinogenic Relatively inexpensive Convenient to apply Should not cause discolouration of the tooth  Root canal irrigants and lubricants Sodium Hypochlorite (NaOCl) Chlorhexidine Gluconate Ehylenediaminetetraacetic Acid (EDTA) A mixture of Tetracycline, an Acid and a detergent (MTAD) Hydrogen peroxide Saline  Sodium Hypochlorite Most commonly used root canal irrigant Most effective of the currently available materials (irrigant of choice) Used at a concentration ranging from 0.5% - 5.25% Various commercially available solutions / dilute house hold bleach  Sodium Hypochlorite Advantages Disadvantages Excellent antibacterial agent potential tissue irritant if it is expressed out of the tooth in to periradicular area Capable of dissolving organic substance foul smell and foul taste present in the root canal system (necrotic & vital pulp tissue, organic components of ability to bleach clothes dentin and biofilm) - Free Cl in NaOCl dissolves vital and necrotic tissue by ability to cause corrosion of metal objects breaking down proteins into amino acids does not remove all the smear layer Lubricate the passage of instruments into the root canal alters the properties of the dentine Hypersensitivity / contact dermatitis - rarely Inexpensive / affordable  Chlorhexidine Gluconate Liquid and gel form has been recommended as an irrigant Usually effective in 2% concentration Advantages of Chlorhexidine Gluconate A broad spectrum antimicrobial agent - active against gram positive and gram negative bacteria , yeasts  Cation – electrostatically binds to negatively charged surfaces of bacteria and damages the outer layer of the bacterial cell wall Substantivity / substantive antibacterial action –reversibly adsorbed by anionic substrates such as oral mucosa, salivary proteins, pellicle on the tooth surface, hydroxyapatite in teeth  Non / low toxicity Non antigenic No foul smell and bad taste Act as a lubricant Disadvantages Not capable of dissolving organic substances and necrotic tissue present in the root canal system Unable to kill all bacteria Cannot remove the smear layer  EDTA (Ethylenediaminetetraacetic Acid) Used in a concentration of 17% Can chelate and remove the mineralized / inorganic portion of the smear layer Can detach biofilms adhering to root canal walls Has the ability of decalcification , it can open up an occluded very fine root canals Relatively non toxic Lubrication of files in the root canal Has a lower value alone as an irrigation fluid. Relatively limited antiseptic capacity  MTAD Based on a mixture of antibiotic (3% doxycycline hyclate), 4.25% Citric Acid, and a detergent (0.5% polysorbate-80) – BioPure MTAD Available in the form of a liquid and powder and need to be mixed prior to use Able to remove the smear layer and disinfect the root canal system Antimicrobial activity- esp effective against E. fecalis Sustained antibacterial activity Bio compatible Less surface tension , more readily penetrate into the root canal system Recommended as a final rinse after completion of chemomechanical preparation  Hydrogen Peroxide Concentration ranging from 3% - 5% Active against bacteria, viruses and yeasts Reduced tissue dissolving ability No longer recommended as a routine irrigant  Normal Saline Not an effective root canal irrigant alone Used as an adjunct to chemical irrigant Can use as a final rinse to remove chemical irritant after preparation Basically act by flushing action Do not have disinfecting antimicrobial and dissolving properties Do not remove smear layer Biocompatible - no adverse effects if extruded periapically  Intracanal medicaments If the root canal treatment cannot be completed in single visit  Cannot obtain pulpal anaesthesia  Incomplete root apex  Pathological processes – pus discharge / resorption of root Functions  Primary function –  Inhibit proliferation of the surviving bacteria within the root canal after mechanical preparation and irrigation  Eliminate / eradicate surviving bacteria and neutralize toxins  Minimize ingress of bacteria through a leaky coronal restoration  Intracanal medicaments ctd… Secondary functions modulate environmental pH and create favourable biological conditions for periapical tissue repair and regeneration – hard tissue formation / resorption control Exudate control Pain control – antimicrobial action / pharmacological action alters the inflammatory response  Ideal properties of an Intracanal medicament Strong Antimicrobial abilities neutralizing toxins and sustained disinfection capability Permeability and followability - Penetrate in to dentinal tubules Formation of physical –chemical barrier within the root canal Control exudation or bleeding Excellent Bio compatibility reducing inflammation in periapical tissues without causing additional irritation to the apical tissues Not interfere with repair, induction of healing and hard tissue formation in periapical tissues Easily removable Radiopaque Does not stain the tooth  Intracanal medicaments Non setting Calcium Hydroxide paste Corticosteroids / Ledermix Triple antibiotics paste Chlorhexidine gel Phenolic preparations / Paramonochlorophenol  Calcium Hydroxide Introduced in 1920 by Herman Widely used as an intracanal medicament Used as non setting Calcium Hydroxide paste  Powder, vehicle, opacifier  Vehicle – aqueous, viscous, oily Functions – Ca2+ and OH-ions Inhibits microbial growth in canals – used in infected canals  Antibacterial effect is due to its alkaline pH Dissolves necrotic tissue remnants, bacteria and their byproducts Promotes mineralized tissue formation and facilitate repair of periapical hard tissues  Calcium Hydroxide Limitations of Calcium Hydroxide Handling and proper placement in the root canal is challenging Difficult to remove completely - shorten the setting time of ZnO/E based endodontic sealers, compromise the quality of RCT Not effective against several endodontic pathogens - Enterococcus fecalis and Candida albicans Cytotoxic Reduce the fracture resistance of dentine  Ledermix Ledermix is a corticosteroid antibiotic paste Non setting, water soluble paste Composition  1% Triamcenolone acetonide as an anti-inflammatory agent  3% Demeclocycline Used as an initial dressing particularly if the patient presents with endodontic symptoms Placed in replanted teeth to inhibit root resorption Limitations Immunosuppression Tooth disclouration  Triple Antibiotics Paste Composed of Metronidazole, Ciprofloxacin and Minocycline (1:1:1) Active against a wide range of bacteria- Effective against Escherichia coli Aids in disinfecting and sterilizing the root canal system Possess a good regeneration inducing potential – Commonly used in regenerative endodontic treatment Concerns May cause bacterial resistance Minocycline can cause tooth discolouration Complete removal from the root canal is challenging Effectively targets metabolically active microorganisms only  Iodine Potassium Iodide -IKI Has a wide spectrum of antimicrobial activity Effective against resistance strains – E. faecalis Used in concentrations ranging from 2%-5% Low tissue toxicity Disadvantage – possible allergic reaction in some patients Less commonly used due to the presence of other medicaments  Phenolic Preparations One of the oldest antimicrobial used in medicine Strong antiseptics Highly toxic agents Possible mutagenic and carcinogenic effects Their use is now decreased  Materials used in root canal obturation After preparation of the root canals, the prepared space must be obturated with a material capable of completely preventing communication with the oral cavity and periapical tissues (coronally, apically and laterally) Achieved by - Root canal sealer and a Bulk fill material (semi- solid or solid)  Properties of an ideal oburating material Biocompatible – non irritating to the periapical tissues Ample working time Easy to manipulate Seal the canal apically and laterally conforming to its complex internal anatomy Should be plastic during placement to allow them to be moulded to the canal form Dimensionally stable – no shrinkage once inserted Impermeable to moisture / tissue fluids – no corrosion / oxidation  Properties of an ideal oburating material Radio opaque and easily discernible in radiographs Easy to remove from the canal if necessary Does not discolour tooth structure Sterile Inhibits bacterial growth Relatively inexpensive  Bulk - fill / core materials Solids/ semi solid Gutta percha Resilon Siver cones – not used any more  Gutta-Percha Commonly used root filling material / core material Derived from a tropical plant of Palaquium genus A high molecular weight polymer Chemical structure closely resembles natural rubber (polyisoprene) GP is the Trans isomer of polyisoprene Less elastic and harder than natural rubber Produced in two crystalline forms – α and β  Gutta-Percha α form - natural form (occurs in the tree) β form - processed form - most commercially available products Available as tapered GP cones (β) / Pellets to be loaded to a gun type delivery system (α)  Gutta percha ctd…. Undergoes phase transitions when heated  Gutta percha ctd…. Compositon 20% Gutta percha 60% - 75% Zinc Oxide – major component 5% - 10% - Radiopacifiers, various resins, waxes and metal sulfates Coated Gutta percha - coated with a resin coating (EndoRez points) Resin bond is formed with resin sealers (EndoRez sealer) Medicated Gutta percha – impregnated with antibacterial substances Chlorhexidine, Calcium Hydroxide, Iodoform, Tetracycline Clinical effectiveness has not been demonstrated  Gutta percha ctd…. Properties Has plasticity Easy to manipulate Minimal toxicity Radiopaque Easy to remove with heat or solvents Disadvantages Lack of adhesion to dentine Not flowable in room temperature , Can be made to flow if it is heated Shrinkage of cooling  Polyester Resins /Resilon Thermoplastic, synthetic , polymer based root canal filling material Developed to create an adhesive bond between the solid core material and the sealer - monoblock Designed to be used with a specific resin sealer (Epiphany) which has a bonding capacity to dentine Available as cones and pellets as GP Can be softened with heat or dissolved with solvents (Chloroform) Compatible with current restorative techniques when cores and posts are placed with resin bonding agents Composition Bioactive glass Raidopaque fillers – Bismuth Oxychloride and Barium Sulfate (65%)  Silver cones / Silver points Introduced in the 1930s due to limitations of canal preparation instruments Rigid – easy to place, more predictable length control Unable to fill the irregularly shaped root canal system – permitted leakage Corrode when contact with tissue fluids or saliva and produce cytotoxic corrosion products- produce pathosis / impede periapical healing Use of silver cones is considered to be below standard of care  Sealers and Cements Bulk fill materials lacks adherent properties to seal the root canal space Functions of a sealer Helps to achieve a fluid tight seal Seal the space between the dentinal wall and the core obturation material Fill voids and irregularities in the root canal, lateral and accessory canals Fill spaces between gutta percha points used in lateral condensation Serve as lubricants during obturation process Acts as a marker for accessory canals, resorptive defects, root fractures and other spaces in to which the main core material may not penetrate  Ideal properties of a sealer Biocompatible and well tolerated by periradicular tissues Can be mixed easily with liquid Exhibit tackiness when mixed to provide good adhesion between the sealer and the canal wall when set Establishes a hermetic seal Radiopaque, can be seen in a radiograph Dimensional stability - No shrinkage on setting No staining of tooth structure Bacteriostatic / not encourage bacterial growth Insoluble in tissue fluids Adequate working time Readily removable if necessary  Sealers- classification Based on the constituents : Zinc Oxide Eugenol sealers / cements Calcium Hydroxide Sealers Glass Ionomer based sealers Silicon based sealers Resin based sealers Bioceramic sealers  Zinc Oxide –Eugenol sealers Have been used for a long time Available as powder / liquid form or a two paste preparation Will absorb if extruded in to periradicular tissues Antimicrobial effect – ZnO Anti-inflammatory effect Once set, becomes weak and porous – susceptible to decomposition in tissue fluids Shrinks on setting Stains tooth structure Free eugenol remains in the mass and acts as an irritant  Calcium Hydroxide Sealers Antimicrobial – release of hydroxyl ions, high pH Lower cytotoxicity Promotes tissue healing Poor cohesive strength Easily disintegrate in the tissue, and cause chronic inflammation Adhesion to the prepared dentin is a concern  Glass Ionomer Sealers Bond with the dentine – enables adhesion between the obturation material and the canal wall Less soluble in tissue fluids Sustained F- release Increased resistance to root fracture Difficult to remove if re –treatment is required Minimal antibacterial activity  Resin based Sealers Provide excellent adhesion to canal walls Two types Epoxy resin based Methacrylate resin based Do not contain eugenol Good tolerability from apical tissues Allergenic and mutagenic potential  Silicon based sealers Addition type of silicon Excellent biocompatibility Insoluble Expand slightly on setting – good sealing ability Highly radiopaque  Bio ceramic sealers Relatively new technology in endodontics Composed of bioceramic materials Calcium Silicate Calcium phosphate Excellent biocompatibility Dimensionally stable Low solubility Non toxic Antimicrobial properties Good sealing ability - enhanced adhesion between the material and the dentin wall difficult to remove in retreatment Promotes tissue regeneration  Materials used for obruration in primary teeth Ideal properties Antiseptic effect – keep root free from infection Resorbed with same rate of primary root Excess beyond root apex should be easily and quickly absorbed Non irritant to the periapical tissues and underlying permanent successor Radio opaque Does not discolour the tooth Should not shrink and be easily removed if necessary Fill the root canal and adhere to the walls of the canal  Materials used for obruration in primary teeth ZnO/E paste Iodoform paste (KRI paste) Calcium hydroxide with Iodoform  ZnO/Eugenol paste Most commonly used root canal filling material for primary teeth Good antibacterial properties It decreases tooth pain Rate of resorption is slower than that of the primary tooth root Overfilling causes a mild foreign body reaction  Iodoform paste / KRI paste Mixture of Idodoform Camphor Parachlorophenol menthol Resorbs rapidly Has no undesirable effect on successor teeth Rapidly resorbed if extruded into periapical tissue Good antimicrobial action Can discolour the tooth  Calcium Hydroxide with Iodoform Easy to apply Resorbs at a slightly faster rate than that of the roots No toxic effects on the permanent successor Radiopaque  Materials used in root end repair Apicectomy For persisting infection after acceptable RCT  Materials used in root end repair Ideal properties Adhere and adapt to the walls of the root preparation Prevent leakage of microorganisms and their products into the periradicular tissues Be biocompatible Non resorbable Unaffected by moisture Easy to prepare and place Readiographically visible Have anticaries activity Non toxic, non carcinogenic and dimensionally stable Should not corrode or be electrochemically active Should have antibacterial effects Should stimulate cementogenesis Well tolerated by periradicular tissues with no inflammatory reactions  Materials used in root end repair Amalgam – was the material of choice MTA - ability to promote tissue regeneration GIC Super EBA/ Epoxy Benzoic Acid – modification of ZnO/E IRM / Intermediate Restorative material – Resin reinforced ZnO/E cement Diaket - Polyvinyl resin Composite resins THANK YOU