bio compatibility of endodontics materials ppt .pptx

Endodontics

1. BIOCOMPATABILITY OF DENTAL RESTORATION PRESENTED BY JOSHIL ADOLF EBIRAJ DEPARTMENT OF CONSERVATIVE DENTISTRY & ENDODONTICS PG 1 ST YEAR

2. SYNOPSIS Background Historical perspective Definition Introduction CRITERIA FOR BIOCOMPATABILITY OF DENTAL METERIALS FACTORS AFFECTING THE BIOCOMPATIBILITY ADVERSE EFFECTS OF DENTAL MATERIALS

3. BACKGROUND Although the concept of the ethical treatment of patients extends back to the time of Hippocrates (460-377 KC.), the idea that new dental materials must be tested for safety and efficacy before clinical use is much more recent. As late as the mid 1800s,dentists tried new materials for the first time by putting them into patients' mouths. Adverse reactions are becoming prevalent in the general population because of the materials used for dental filling and orthodontic instruments. Due to its long time in the oral cavity, it is essential to prevent an adverse reaction. https://www.researchgate.net/publication/281876361_Biocompatibility_of_Dental_Materials_A_Comprehensive_Review

4. Before 400BC, the Etruscans fabricated bridges and partial dentures using gold combined with animal or extracted human teeth. Autian (1970) was the first to propose a concept consisting of three levels. They are: Nonspecific toxicity (cell cultures or small laboratory animals); Specific toxicity (usage tests, e.g. in subhuman primates); Clinical testing in humans. According to Autian (1970) the term 'non specific‘ refers to test systems which do not reflect the application of a material in a clinical situation whilst the term specific‘ applies to the use of biological models simulating the actual clinical use of the material.(Stein et al., 2005) The following sequence was adopted by the ISO (1984) in Technical Report 7405: Initial tests (cytotoxicity, mutagenicity); Secondary tests (sensitization, implantation tests, mucosal irritation); Usage tests. In both concepts, newly developed materials should be subjected to the three steps in the given sequence from the simple to the complicated test method, from in vitro to animal tests and from preclinical to clinical testing on humans.

5. “Practitioners should understand that there are no inert materials. When material is placed into living tissue, interaction with the complex biologic systems around it occur, and those interactions result in some sort of biologic response. Wataha J.C., 2001 Patient BIOCOMPATIBILITY Material Function Material

6. DEFINITION Biocompatibility is defined as the ability of a material to elicit an appropriate biologic response in a given application in the body Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

7. The ability of a biomaterial to perform its desired function with respect to a medical (or dental) therapy, without eliciting any undesirable local or systemic effects in the recipient or beneficiary of that therapy, but generating the most appropriate beneficial cellular or tissue response in that specific situation, and optimizing the clinically relevant performance of that therapy (Williams, 2008);

8. WHY IT IS IMPORTANT TO THE DENTIST?

9. INTRODUCTION The term ‘biocompatible’ is defined as being harmonious with life and not having toxic or injurious effects on biological functions. In general, biocompatibility is measured on the basis of localized cytotoxicity (such as pulp and mucosal response), systemic responses, allergenicity and carcinogenicity. The dental materials or technique or any external stimulus should not be harmful to the pulp and soft tissues. It should not contain toxic diffusible substance that can be absorbed into the circulation to cause a systemic toxic response. Further it should have no carcinogenic potential and also should be free of potentially sensitizing agents that could cause an allergic response.

10. CRITERIA FOR BIOCOMPATABILITY OF DENTAL METERIALS They should not sensitize and produce allergic reactions. They should not undergo biodegradations. They should not be carcinogenic. They should not contain any toxic diffusible substances which get released and enter into the circulatory system. They should not be harmful to soft & hard tissues of the oral cavity in particular and the whole body in general.

11. INTERACTION-TYPES Placement of a material in the body creates an interaction Various types of interactions are, Between the material and oral cavity. Between the material and the pulp (Via the dentinal tubules). Between the material and periodontium. Between the material and the periapical bone.

12. FACTORS AFFECTING THE BIOCOMPATIBILITY The location of material. Its duration in the body. The properties of the material. Health of the host.

13. ADVERSE EFFECTS OF DENTAL MATERIALS Toxicity Inflammation Allergic reaction

14. TOXICITY the ability to damage a biological system by chemical means. Placement of a foreign material Dental materials may release certain substances Types Systemic Local

15. SYSTEMIC TOXICITY It can be classified according to the time frame: 1. Acute (up to an exposure period of 24 h) 2. Subacute (up to 3 months) 3. Chronic toxicity are differentiated

16. LOCAL TOXICITY It can be due to biological or mechanical Bacterial accumulation on the surface, at the margin, or under a material. Mechanical/physical irritation, such as pressure caused by dentures. Inflammation of the gingiva in contact with a porcelain- fused-to-metal crown Pulp necrosis after application of resin fillings

17. INFLAMMATION It is characterized by edema of the tissue On H/e- Presence of Inflammatory cell infiltration such as neutrophils (in the short term) or monocytes and others

18. ALLERGY An allergic reaction to the dental material can be triggered if the host was previously sensitized to this compound. Allergic reaction can be of 4 types

19. ALLERGIES Inflammation of the gingiva in contact with a porcelain- fused-to-metal crown Pulp necrosis after application of resin fillings

20. Allergic contact dermatitis on the fingertip of a dentist after contact with resin-based composite Allergic reaction of type IV (reaction on the hands, distant from the exposure site) after exposure to nickel during an orthodontic treatment (Courtesy of N. Veien , Aalborg, Denmark

21. Pronounced gingivitis of an orthodontic patient (nickel-containing device) who revealed a positive reaction in a patch test. The most important differential diagnosis would be “plaque-associated” inflammation . Persisting perioral and labial eczema of an orthodontic patient (copper–nickel–titanium wires). The patient had no intraoral symptoms, and there was complete regression after replacement with titanium wires

22. Inflammation of the palatal mucosa Reaction beneath a denture Healing of the inflammation after hygiene instructions and rinsing with 0.1% chlorhexidine digluconate

23. Inflammatory response or possible allergic reaction adjacent to a class V resin-based composite. However, no patch test was performed to confirm this response. (Courtesy of Dr. Hyun- Ju Chung.)

24. Possible allergic reaction to nickel alloy in watchband buckle. Bilateral erythema in a female patient that may have been associated with allergic reactions to nickel in a recently cemented metal-ceramic crown (left side of photo) and in two metal-ceramic crowns (right side of photo) of a three-unit fixed dental prosthesis

25. Severe allergic reaction in the lips of a patient who was exposed to a nickel-containing orthodontic wire. Positive responses to patch tests on a patient’s back

26. Large blue-colored areas, typically referred to as an amalgam tattoo, which is a benign area of discolored membrane in the mouth. These examples are not associated with allergic reactions to mercury or any other metallic elements in the amalgam fillings. The discoloration is caused by small amalgam granules that have fallen into open wounds created during the condensation and carving of amalgam fillings in prepared teeth or retrograde fillings in root apices

27. Bilateral lichenoid lesions that are associated with gold alloy crowns. , Lichenoid mucositis lesion (white area) in tissue adjacent to a gold alloy crown. Lichenoid mucositis lesion in vestibular tissue next to gold alloy crown on opposite side of the arch. Patch testing of the patient was not performed.

28. OTHER ADVERSE EFFECTS Mutagenicity It is the ability of a substance to pass genetic damage on the next generation . E.g.: Ni, Cu and Be are known mutagens Carcinogenicity: It is the ability of a material or substance released from it to induce malignant tumours. Genotoxicity: Refers to the ability of substance released from materials to cause alterations of the genome Teratogenicity: It is the ability of certain substance to cause malformation during embryonic development

29. ADVERSE E FFECTS OF DENTAL MATERIALS Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

30. HOW TO KNOW THE BIOCOMPATIBILITY? Historically, new materials were simply tried in humans to see if they were biocompatible. However, this practice has not been acceptable for many years, and current materials must be extensively screened for biocompatibility before they are ever used in humans. Several varieties of tests are currently used to try to ensure that new materials are biologically acceptable. These tests are classified as in vitro, animal, and usage tests.

31. The initial tests (phases I and II) are of a short duration, simple and cost effective. in vitro tests to in vivo tests. Usage test can be performed in animals or humans (clinical trial). usage tests are gold standard - w he the r a mater i al is biocompatible or not.

32. HOW TO KNOW THE BIOCOMPATIBILITY? NUMBER OF MATERIALS CLINICAL USE NEW MATERIALS

33. IN VITRO TESTS 1926: Cell-culture technique 1968: Kawahara reported ‘Cytotoxicity test’ including dental materials. 1972: Leirsker & Helgeland reported the use of L-929 cells to assess biocompatibility of amalgam, resin, silicate cement and gold base alloy. 1973: Spangberg reported the 1st quantitative measure of biological response in vitro using 51 Cr assay. 1977: Agar overlay test. In vitro purpose to simulate the in vivo conditions in any aspect of cell function or metabolism, including gene expression, signaling activation, protein expression, oxidative stress, etc.

34. IN VITRO TEST Test tube, cell culture dish, flask , or other container CLASSIFICATION OF IN VITRO TESTS D I R E CT T E S T INDIRECT T E S T MATERIAL CONTACT EXTRACT CONTACT

35. DIRECT TEST- MEASURES THE CYTOTOXICITY It measures the c ell number or growth before and after exposure to that material. Interpretation: If the cells remain attached to the well and proliferate over time it indicate that the dental material is not cytotoxic and it is biocompatible. If the cell stop growing or exhibit cytopathic changes or detach from the well it indicate that the dental material is not biocompatible Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

36. DIRECT TEST- MEASURES THE CYTOTOXICITY Histopathological examination finding The morphology of the fibroblasts indicates that they are alive and are not suffering from a toxic response The fibroblasts are rounded and detached indicating that they are either dead or dying .

37. DIRECT TEST- MEMBRANE PERMEABILITY dye can pass through a cell membrane colorimetric or florescent assay wherein the membrane integrity is tested for its permeability. Trypan blue staining,red vital staining,and neutral red staining combined with amido black staining Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

38. 2.TESTS FOR CELL METABOLISM OR CELL FUNCTION: Use biosynthetic or enzymatic activity of cells to assess cytotoxic response Usually assess DNA synthesis or Protein synthesi Types: MTT ( dimetl - thiazole -diphenyl - tetrazolium bromide) XTT (methoxy -nitro – sulphophenyl - tetrazolium carboamine NBT (nitro blue tetrazolium ) WST (water soluble tetrazolium ) ALAMAR BLUE TEST – quantitatively measure cell proliferation using a fluorescent indicator Calorimetric ASSAYS

39. TESTS THAT USE BARRIERS(INDIRECT TESTS) 1. Agar overlay method If the test material is cytotoxic, it will lead to loss of dye within cells as lysis occurs . Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

40. Millipore filter assay A cellulose acetate filter having 0.45µm filter is used Cells are grown on one side and the test material placed on the opposite side of filter. Any leachable substance from the test material must diffuse through the pores to exert a cytotoxic effect on the cells. Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

41. DENTIN DISC BARRIER TEST 25 A DENTIN DISK FORMS A BARRIER BETWEEN THE TEST MATERIAL AND THE TARGET CELLS The material is placed on one side of the dentin disk (B) in the device used to hold the dentin disk. Collection fluid (cell culture medium or saline) is on the other side of the disk (C). Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

42. Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

43. 3.MUTAGENESIS ASSAYS 1. AMES TEST : Mutant strains of the bacteria Salmonella tymphimurium were used. These bacteria contain mutations in the enzyme that synthesize histidine . Histidine in-turn is responsible synthesis of proteins. Bacteria cannot grow and form colonies on a special culture agar, which is histidine-deficient . If any mutagenic substance is present, the growth of the bacteria - mutagenicity . Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

44. IN VITRO TEST ADVANTAGES Quick to perform Least expensive Can be standardized Large scale screening Good experimental control DISADVANTAGES Questionable relevance to the final in vivo use of the material Lack of inflammatory or other tissue protective mechanisms in the in vitro environment Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

45. ANIMAL TEST Vimal K Sikri . Biocompatibility,In . Textbook of operative dentistry. Fourth edition.CBS publisher; 2016. p 258-280.

46. 1.MUCOUS MEMBRANE IRRITATION TEST Placing the test materials and positive and negative controls into contact with rabbit oral tissue. biopsy specimens are prepared for histological evaluation of inflammatory changes.

47. 2.SKIN- SENSITIZATION TEST The materials are injected INTRADERMALLY to test for development of skin hypersensitivity reactions. If hypersensitivity developed from initial injection, the patch will elicit an inflammatory response

48. 3. IMPLANTATION TESTS materials are implanted subcutaneously, intramuscularly, or in the bone of an experimental animal . After different periods (between 1 week and several months), tissue is investigated macroscopically and microscopically. After a short implantation time (1–2 weeks), degrees of inflammation surrounding the implant - assessed. Formation of an abscess at the interface between material and connective tissue Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

49. ANIMAL TEST A D V A N T AGES complex systemic interactions Response more comprehensive than in vitro test More relevant than in vitro test DISADVANTAGES Questionable relevance to the final in vivo use of the material Expensive Time consuming Legal/ethical concerns Difficult to control Difficult to interpret and quantify Vimal K Sikri . Biocompatibility,In . Textbook of operative dentistry. Fourth edition.CBS publisher; 2016. p 258-280.

50. IN USAGE TEST LARGER ANIMALS or IN HUMAN VOLUNTEERS GOLD STANDARD DENTAL PULP IRRITATION TEST MUCOSA AND GINGIVAL USAGE TEST INTRAOSSEOUS IMPLANT TEST Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012. Materials to be placed in a situation identical to its intended clinical use

51. 1. DENTAL PULP IRRITATION TEST Test material placed in class v cavity prepared in intact, non carious teeth Teeth removed, sectioned for microscopic Examination Tissue necrosis and inflammation graded according to intensity Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

52. 2. INTRAOSSEOUS IMPLANT MATERIALS USED FOR I MPLANTS ARE INSERTED INTO THE JAW . Criteria for implant success Early implant success 1-3 years Intermediate implant success 3-7 years Long term implant success >7 years Tests used Passage of periodontal probe along side of the implant Mobility of the implant Radiographic evidence Available data from these studies show that implants based on titanium or ceramics, are generally well tolerated by the surrounding tissue.

53. 3.MUCOSA AND GINGIVAL USAGE TESTS Materials are placed in cavity preparations with sub gingival extensions. Slight, moderate or severe based on amount of inflammatory cells depending on the number of mononuclear inflammatory cells in the epithelium and adjacent connective tissues Disadvantages: Presence of plaque Preexisting inflammation in the gingival tissue Surface roughness of the restorative material Over contouring and under contouring of the restoration.

54. IN USAGE TEST ADVANTAGES Relevance to the use of material is assured DISADVANTAGES Very Expensive Time consuming Major Legal/ethical concerns Can be Difficult to control Difficult to interpret and quantify Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

55. DIAGNOSTIC TESTS ON PATIENT ALLERGY TESTS: Patch test: - ( Type IV) adhesive tapes after 2 and 3 days after 5 and 7 days late reactions Prick test:- (Type I) the allergen as a drop to the skin and pricked

56. ANALYSIS OF INTRAORAL ALLOYS CHIP TEST TO KNOW THE COMPOSITION OF ALLOY A small amount of alloy particles (chips) - silicon carbide stone or a tungsten carbide bur. The alloy particles are collected on a small, circular, self-adhesive graphite plate which conducts electricity and further subjected to Energy Dispersive X-ray Analysis

57. STRATEGIES FOR EVALUATING BIOCOMPATIBILITY Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

58. Disadvantages 1. It is seen that the materials that cleared the first two tests were not entirely harmless at the clinical usage level. E g ZOE when tested in vitro completely kills every cell in the culture, but in clinical practice, the same cement has been successfully used for many years with no evidence of pulp damage. 2. It is time consuming since it is performed in a sequential manner. Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

59. Biocompatibility Of Various Dental Materials

60. BONDING AGENTS May penetrate upto 0.5 mm in dentin and cause supression of cellular metabolism HEMA 100 times less cytotoxic than Bis-GMA Release of MMPs acid components of dentin adhesives degradation of adhesive bond enzymatic action on exposed collagen within the hybrid layer. The application of an MMP inhibitor Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

61. RESIN BASED COMPOSITES The dental personnel - contact dermatitis and asthma by methacrylates Moderate cytotoxic reactions in cultured cells over 24 to 72 hours of exposure Light-cured resins ˂ chemically cured dependent on the curing and the type of resin P ulpal inflammatory response was low to moderate with sufficient remaining dentine With a protective liner or a bonding agent , the reaction of the pulp to resin composite materials is minimal. Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

62. PRECAUTIONS S ui table base should be placed to protect the pulp from bacterial toxins Inhalation - rubber dam or the use of suction/water coolant. Protective shields to protect the eyes A voi d an y contac t o f s k 5 in Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

63. Extraoral allergic reactions (type I) after application of a pit and fissure sealant Allergic contact dermatitis of a dentist after contact with resin-based composites Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

64. Gingivitis adjacent to a cervical composite resin filling Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253 Allergic reaction to class V resin based composites

65. Silver Amalgam Systemic toxicity Elemental Mercury -systemic toxicity. It can enter into human body through the skin, by ingestion or by inhalation of mercury vapours. sources of mercury exposure Improper storage Exposure during manipulation i.e trituration , insertion Exposure during finishing andpolishing . Removal of old amalgam restorations. Safe level of mercury exposure in the dental office is 50 µg Hg / Cubic Meter of air /day.

66. Local Toxicity Pulp Reactions : Reduced number of odontoblast . Dilated capillaries. An inflammatory cell reaction - odontoblastic layer - condensation of amalgam in deep cavities. Oral Mucosa reactions : Gingivitis Bleeding gums Bone loss around teeth Desquamation of buccal or lingual mucosa Amalgam Tattoos Allergic reaction Type 1V – Delayed allergic type reaction -Oral Lichenoid Reactions, which resolve on removal

67. Amalgam tattoo due to condensation of amalgam Amalgam tattoo due to retrograde filling Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

68. DENTAL CASTING ALLOYS The biological response to an alloy depends on biological effects of released elements, quant ity duration . A number of factors influence the corrosion of dental alloys : Composition of the alloy (particularly at the surface) Surface structure (roughness, presence of oxides) Crevices, pits Thermal treatment/history Combinations of alloys (gold coating, soldering ) Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

69. Lichenoid lesions associated with gold alloy crowns Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

70. Positive reaction to patch test Allergic reaction to nickel in metal ceramic crown Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

71. SY S TE M IC TOXICITY elements released from the dental alloys is far below the dietary intake; for e.g. the amount of zinc released (< 0.1µg /day ) daily dietary intake (14,250µg /day). LOCAL TOXICITY epithelial cells of the sulcus will be more prone to cytotoxicity. Ni, Cr, Co - Cytotoxic Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

72. Allergic Rea c t i o n s The incidence of nickel allergy is 15% and that of Co and Cr is 8%. Cross –reactive allergy can occur for Pd and Ni. Lichenoid reactions OTHER R E AC T I O NS Vapor form of elements such as beryllium is a common mutagenic threat. Beryllium is a carcinogen in either the metallic or ionic state. When inhaled and reach the alveoli of the lungs - chronic inflammatory condition called BERYLLIOSIS Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

73. gingivitis due to the PFM crowns; after removal of the crowns and seating of temporary resin crowns Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

74. Gold coating of nickel-based and cobalt-based alloys. Pronounced redness of the palate beneath the denture base. Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

75. Perioral allergic reaction after insertion of nickel-containing orthodontic wires (CuNiTi) Lichenoid reaction of the mucosa contacting an alloy Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

76. Pronounced gingivitis after seating of ceramic crowns, despite good oral hygiene Dental lab –Inhaled beryllium – berylliosis. Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

77. GLASS IONOMER CEMENTS Freshly prepared ionomer is mildly cytotoxic Resin modified GIC is more cytotoxic Pulpal reaction is mild. Large size of molecules of Polyacrylic Acid unable to diffuse through dentinal tubules Histological studies in usage test shows that inflammatory infiltrate to GIC is minimal or absent after 1 month. Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502. Sinha DJ, Sinha AA, Vasudeva A, Jaiswal N. Biocompatibility of Dental Materials: A Comprehensive Review. Indian Journal of Contemporary Dentistry. 2015;3(2):1-5.

78. LINERS, VARNISHES, AND NON RESIN CEM ENTS CALCIUM HYDROXIDE ZINC PHOSPHATE ZINC POLYCARBOXYLATE CEMENT ZOE CEMENT Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

79. CALCIUM HYDROXIDE CEMENT Local toxicity Tertiary dentin will be triggered only if the remaining dentin thickness(RDT) is 5 to10 µm. Direct pulp capping material: produces superficial coagulation necrosis. This acts like a stimulus for the differentiation of secondary odontoblasts that lay down tertiary dentin. Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502. Sinha DJ, Sinha AA, Vasudeva A, Jaiswal N. Biocompatibility of Dental Materials: A Comprehensive Review. Indian Journal of Contemporary Dentistry. 2015;3(2):1-5.

80. ZINC PHOSPHATE CEMENT The acidity of the cement initially very high due to phosphoric acid (pH is around 3.5 during application). Subsequently, it increases within 24-48 hours. Precautions to be taken are as follows: The powder/liquid ratio should never be reduced The placement of a protective layer Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253 Sinha DJ, Sinha AA, Vasudeva A, Jaiswal N. Biocompatibility of Dental Materials: A Comprehensive Review. Indian Journal of Contemporary Dentistry. 2015;3(2):1-5.

81. Zinc phosphate cement that was left in the sulcus after cementation results in periodontal destruction and bone loss Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502. Chemical burn after inadvertent contact of phosphoric acid with gingiva

82. ZINC POLYCARBOXYLATE CEMENT Polyacrylate cements evoke a pulpal response similar to that caused by ZOE, with a slight-to-moderate response after 3 days and only mild, chronic inflammation after 5 weeks. Reparative dentin formation is minimal and thus they are recommended only in cavities with intact dentin in the floors of the cavity preparations. Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

83. ZIN C OXIDE EUGENOL CEMENT • Reaction of the gingiva after temporary cementation of a crown with a zinc oxide and eugenol cement. Local Toxicity Pulp reaction Cytotoxic reaction when directly applied to the pulp. If there is a complete dentin layer between the pulp and the cement, no inflammatory reaction will occur. [LEAST IRRITATING OF ALL : pH 6.6 -8 i.e. Mild pulpal response] Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

84. Allergic Reaction Eugenol can induce an allergic response - Allergic contact dermatitis. Other reaction Eugenol was mutagenic in the mouse micronucleus test . Based on these findings, the use of ZOE materials is not recommended Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

85. PRECAUTIONS DURING CEMENTATION Apply petroleum jelly to the surrounding soft tissues Clean the excess cement after luting the prosthesis Any residues of cement left in the gingival sulcus will lead to inflammation Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

86. DENTAL CERAMICS S y s te m i c toxicity Risk of silicosis due to inhalation of ceramic dust. Silicosis is a lung diseases characterized by shortness of breath, cough, fever, and cyanosis. Dust removal measures should be followed in the laboratory. Local toxicity Most ceramics are biocompatible . Other reac t ions Zirconium oxide ceramics show some amount of radioactivity due to contaminants such as thorium and uranium. Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

87. IMPRESSION MATERIALS Addition Silicone Hydrocollo i ds Polysulphides - contain lead peroxide, among others, which can cause acute and severe systemic toxic effects when swallowed or inhaled Polye t her ZnoE least biocompatibility applies to condensation silicones N O N T O X IC ALLERGIC REACTIONS Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

88. Direct and repeated skin contact by dental personnel - should be avoided. Contact with the eyes, when mixing a liquid catalyst into a putty impression material by hand, should also be avoided, prevention s uch as by wearing protective glasses or by using a paste catalyst. subgingival area of the sulcus to be carefully controlled with deep periodontal pockets. Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

89. POLY-METHYLMETHACRYLATE RESINS Denture base materials: MMA Monomer is the main cause for hyper sensitization Hypersensitivity has been documented to the acrylic and diacrylic monomers, certain curing agents, antioxidants, amines, and formaldehyde Two aspects are of particular importance: monomer– polymer conversion and residual monomer content. Powers JM, Sakaguchi RL, Craig RG. Biocompatibility. In: Craig's restorative dental materials/edited by Ronald L. Sakaguchi , John M. Powers. Philadelphia, PA: Elsevier/Mosby; 2012.

90. True allergy of oral mucosa to denture base material is very rare Residual monomer (methyl methacrylate) is believed to be responsible for allergic reactions in susceptible patients Allergic acrylic stomatitis – diffuse erythema, edema & occasionally small vesicles and erosions Heat polymerized is better than Autopolymerized resin Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253 Sinha DJ, Sinha AA, Vasudeva A, Jaiswal N. Biocompatibility of Dental Materials: A Comprehensive Review. Indian Journal of Contemporary Dentistry. 2015;3(2):1-5.

91. Dentist suffering from an allergy to methyl methacrylate contact dermatitis Pronounced inflammation of the palatal mucosa beneath a polymethyl methacrylate denture with papillary hyperplasia Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253 Sinha DJ, Sinha AA, Vasudeva A, Jaiswal N. Biocompatibility of Dental Materials: A Comprehensive Review. Indian Journal of Contemporary Dentistry. 2015;3(2):1-5.

92. Erythematous reaction sites due to acrylic appliance Anusavice KJ, Shen C, Rawls HR, editors. Biocompatibility.In . Phillips' science of dental materials. Eleventh edition: Elsevier Health Sciences; 2012 Sep. p. 239-253

93. BARRIER MATERIALS Latex : The incidence of latex allergy is about 9.7% and 6% among patients and dental staff, respectively. Latex products can produce either: Type 1 immediate atopic/anaphylactic reaction - due to proteins present in natural latex Type 1V delayed hypersensitivity reaction (allergic contact dermatitis): due to accelerators and antioxidants used in latex manufacturing. Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

94. Precaution to be taken are as follows: Non latex synthetic materials such as nitrile and styrene ethylene butadiene should be used. Polyethylene or polyvinyl chloride rubber dams can be used instead of latex Contact urticaria following occupational exposure to latex proteins in disposable gloves severe irritative hand dermatitis caused by frequent hand washing and wearing of disposable gloves Mahalaxmi S. Materials Used in Dentistry. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013. p 489-502.

95. ROOT CANAL SEALERS Systemic toxicity There is no systemic toxicity paraformaldehyde containing sealers (N2) - heavy metals -lead and mercury. These metals can transport to vital organs via blood & hence there use is discontinued. Local Toxicity Para formaldehyde containing sealers : Severe cytotoxic response. They can irreversibly affect nerve conduction and result in paresthesia . ZOE based sealers : Moderate cytotoxic response. 3. Resin – based sealers: Cytotoxicity is less than that of para formaldehyde containing sealers. 4. Ca Hydroxide based sealers: Less cytotoxic

96. Allergic Reaction Paraformaldehyde -act as an allergens and ananaphylactic reaction. ZnoE sealers: allergic because of eugenol . Resin – based sealers: Allergic because of bisphenol A Diglycidyl ether (BADGE) which is contact allergen. Other Reactions Sealers having mutagenic potential are: Paraformaldehyde containing sealers Unset resin –based sealers

97. OBTURATING MATERIALS Systemic toxicity No Systemic toxicity Local toxicity Silver points -corrosion potential. Gutta – percha is only slightly cytotoxic [in cell culture]. 3. Resilon points : Cytotoxic probably due to (HEMA). 4. MTA : Least cytotoxic . The cytotoxicity is similar to the chemically inert titanium alloy Allergic reaction Proteins of gutta – percha are removed by a purification process. Use of impure forms of gutta – percha -an allergic reaction. Some Balata,a dried juice of Brazilian Trees, to make gutta percha points. Balata is known to cause cross – reactivity with latex .

98. Dental amalgam

99. dental adhesives

100. composites

101. Eugenol

102. Other reactions

103. CONCLUSION Due to rise in number of patients with allergies from different materials, the practicing dentists should be aware about the allergies documented to known materials For establishing diagnosis, it is essential to obtain proper history related to allergy, clinical examination and confirmatory tests. Benefit outweigh the risk

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108. Thank you ..