Word Files
Reference for Downloading Educational Files
  2. Medical Sciences
  3. Comparative investigation of fracture resistance of teeth restored with different techniques and composites with different bases

Comparative investigation of fracture resistance of teeth restored with different techniques and composites with different bases

Number of pages: 90 File Format: word File Code: 32030
Year: 2012 University Degree: Master's degree Category: Medical Sciences
Tags/Keywords: Composite - Composite resin - dental tissue - failure strength - Methacrylate - Restored teeth - sailors - tooth fracture
  • Part of the Content
  • Contents & Resources

  • Summary of Comparative investigation of fracture resistance of teeth restored with different techniques and composites with different bases

    Dissertation for receiving a doctorate degree in dentistry

    Introduction

    Removing large amounts of dental tissue weakens the restored tooth. The type of restoration method and composite can be one of the influencing factors on tooth fracture resistance under occlusal forces.

    Objective

    The purpose of this study was to investigate the effect of using new low-shrinkage composites on the fracture strength of premolars with MOD cavities.

    Method and materials

    Number 60 healthy human maxillary premolar teeth that were extracted for orthodontic purposes were selected and MOD standard class two cavities were cut in 50 teeth. The samples were divided into 4 groups of 10 based on the restoration method and the type of composite used: First group: posterior composite (FiltekTM P60); The second group: 0.5 mm middle layer of glass ionomer (Fuji LC) + posterior composite (FiltekTM P60); The third group: 0.5 mm intermediate layer of Flowable composite (FiltekTM Supreme XT) + posterior composite (FiltekTM P60) and the fourth group: Low shrink posterior composite (FiltekTM P90). 10 uncut and unrepaired teeth remained as the negative control group (fifth group) and 10 uncut teeth remained as the positive control group (sixth group). The samples were subjected to a thousand thermal cycles and then the fracture resistance test was performed with an Instron device (with a speed of 1 mm/min). Also, at the end, the fracture pattern of the samples was recorded based on the involvement of the tooth structure and restoration. The data were analyzed by one-factor analysis of variance and Tukey and Fisher tests.

    Findings

    The group in which the teeth were unground and the group in which the ground teeth were unrepaired had the highest and lowest fracture resistance, respectively (P-Value < 0.05). Also, the second and third groups, which were not significantly different from each other, showed the highest fracture resistance after uncut samples (P-Value < 0.05). The type of fracture was not related to the four groups that were filled with various types of restorative methods (P-Value > 0.05).

    Conclusion

    This study showed that different restorative techniques were effective on the fracture resistance of premolar teeth with large MOD cavities. Also, Siloran restorative system could not be effective in strengthening the fracture resistance of teeth compared to methacrylate.

    Key words: Composite resin, siloran, fracture strength

     

     

     

     

    Chapter One

    Review of texts and articles

    Introduction

    Today, resin composite restorations are widely used in dentistry. So far, several modifications have been made on the composition of composites and in order to improve their clinical performance. Nevertheless, composite resins are still far from ideal due to some shortcomings.

    One of the most challenging problems of composite resins is their significant shrinkage during polymerization. The stress caused by polymerization shrinkage can be the most important factor in adhesive failure, inadequate marginal matching, and finally the creation of secondary caries. Based on extensive studies on polymerization shrinkage and stresses caused by dental composites, several solutions have been proposed to reduce this shrinkage and its effects. Some of these methods are: Incremental layer placement technique, polymerization starting from low intensity, using intermediate layers with low elastic coefficient as stress breaker and using composites with modified resin base. (1)

    One of the newest methods is using open ring polymerization of siloran molecules instead of free radical polymerization of dimethacrylate monomers.(2)

    Siloran is a restorative material with minimal shrinkage and the same color as the tooth, which has recently entered the dental market. The name Siloran is a combination of the two names Siloxan and Oxirane.  Siloxan is responsible for the extremely hydrophilic nature of siloranes, and the cycloalipathic functional oxirane groups are also responsible for the lower shrinkage compared to bis-methacrylate composites.  Oxiranes, which are cyclic ethers, are polymerized by the mechanism of cationic ring opening, while the polymerization of methacrylates is by the mechanism of free radicals. Conventionally, the term dental composite refers to a mixture of silicate glass with acrylic monomer, which starts to polymerize when mixed. Silicate particles provide mechanical reinforcement (reinforcing fillers) of the mixture and allow light to pass and diffuse, which gives the mixture a transparency similar to enamel. (3) During recent years, there have been many changes in the clinical characteristics of composites. These changes include increasing the filler content, changing the types of fillers and resin formulation, and producing new hybrid composites, ion-released, packable ormocer, (organically modified ceramics). (4)

    Although significant advantages such as beauty, low thermal conductivity, easy clinical application, and wear resistance have been mentioned about these materials, the polymerization shrinkage of these materials with a resin base is still their biggest drawback. is considered Shrinkage-related contraction stress can lead to debonding of the composite from the tooth surface and cause sensitivity after work, enamel cracks, recurrence of caries, discoloration of the margin of the restoration (marginal) and ultimately failure of the restoration. Composite resin is a combination of four main components: organic polymer matrix (continuous phase), inorganic filler particles (dispersed phase), coupling material (binding agents or interface layer) and other factors such as initiator-accelerator system, inhibitors, color stabilizers and pigments. (7)

    Polymer matrix Organic:

        In most commercial composites, it is an aromatic diacrylate oligomer or aruthane.  

    Statement of the problem

    Removal of large amount of sound tooth may result in weakened restored tooth. The type of restorative technique and resin composite may be effective factors on fracture resistance of tooth under occlusal load.

    Aim

    The aim of this study was to evaluate the fracture resistance of premolar teeth with large MOD preparations restored with low shrinkage composite.

    Method and materials

    Sixty sound human maxillary premolars extracted for orthodontic reasons were selected. Standardized MOD cavity preparations were made in 50 teeth. Specimens were divided into four groups of 10 teeth based on the type of restorative technique and resin composite: G1: Restoration with posterior composite alone (FiltekTM P60); G2: 0.5mm Glass Ionomer (Fuji LC) + posterior composite (FiltekTM P60); G3: 0.5mm flowable composite liner (FiltekTM Supreme XT) + posterior composite (FiltekTMP60); G4: Restoration with low shrink posterior composite alone (FiltekTM P90). 10 prepared but unrestored teeth (G5) and 10 intact teeth (G6) remained as negative and positive control groups respectively. The specimens were thermocycled and loaded vertically in an Instron Testing Machine with a speed of 1mm/min. The types of fractures were recorded based on the involvement of tooth structure or restoration. The data were analyzed by one-way ANOVA and Tukey HDS and Chi-Square tests.

  • Contents & References of Comparative investigation of fracture resistance of teeth restored with different techniques and composites with different bases

    List:

    Persian summary.1

    Chapter one: review of texts and articles

    Introduction..3

    Overview..5

    Introduction of composite resin. 5

    Components of composites. 6

    Classification of composites. 11

    Properties of composites. 13

    Polymerization shrinkage. 13

    Mechanical properties. 15

    Thermal properties. 16

    Water absorption.. 16

    Abrasion.. 16

    Introduction of siloran composites. Chewing. 21

    A review of articles. 23

    Composite and fracture strength of teeth. 23

    Silorans.. 31

    Statement of the problem and the necessity of conducting research. 42

    Objectives and assumptions.

    Collection and mounting of samples.47

    Preparation of holes..48

    Stages of restoration of samples. Recommendations

    Conclusion..67

    Suggestions..67

     

    References..68

    English summary

     

     

     

    Source:

     

    Navarra CO, Cadenaro M, Armstrong SR, Jessop J, Antoniolli F, et al. Degree of conversion of Filtek Silorane Adhesive System and Clearfil SE Bond within the hybrid and adhesive layer: An in situ Raman analysis. Dent Mater. 2009;25(9):1178-85.

    Tezvergil-Multuay A, Lassila LV, Vallittu PK. Incremental layers bonding of silorane composite: The initial bonding properties. J Dent. 2008;36(7):560-3.

    Roberson TM, Heymann HO, Swift EJ. Sturdevant's art and sciences of operative dentistry. 5 th ed. USA: Duncan L; 2006.P. 648-54, 140, 245-59, 181-9, 262-4.

    Civelek A, Ersoy M, L'Hotelier E, Soyman M, Say EC. Polymerization shrinkage and microleakage in class II cavities of various resin composites. Oper Dent 2003;28(5):635-41.

    Al-Boni R, Raja O. Microleakage evaluation of silorane based composite versus methacrylate based composite. J Conserv Dent. 2010;13(3):152-5.

    Charton C, Colon P, Pla F. Shrinkage stress in light-cured composite resins: Influence of material and photoactivation mode. Dent Mater. 2007;23(8):911-20.

    Kugel G. Direct and indirect adhesive restorative materials: A review. Am J Dent 2000; 13(Spec No):35D-40D.

    Powers JM, Sakagushi RL. Editors. Craig's restorative dental materials. 12th ed.St Louis: Mosby Co; 2006.p.190-192,194,198,5,63,64.

    Bowen RL. Properties of silica reinforced polymer for dental restorations. J Am Dent Assoc. 1963;66:57-64.

    Phillips RW. Skinner's science of dental materials. 9th ed. Philadelphia: WB Saunders; 1991.

    Hilton TJ, Broome JC. Direct Posterior Aesthetic Restorations. In: Sumitt JB, Hilton TJ, Schwartz RS. Fundamentals of Operative Dentistry: A Contemporary Approach. 3rd ed. London: Quintessence Pub Co; 2006.

    Sturdevant CM, Roberson TM, Heymann HO. The art and sciences of operative dentistry. 3 th ed. Mosby; 1994.

    Dental material properties and manipulation. 2000.

    Chung KH. The relationship between composition and properties of posterior resin composites. J Dent Res. 1990;69(3):852-6.

    Bayne SC. Heymann Ho. Swift EJ Jr: Update on dental composite restorations. J Am Dent Assoc. 1994;125(6):687-701.

    Lang BR, Jaarda M, Wang RF: Filler particle size and composite resin classification system. J Oral Rehabil. 1992;19(6):569-84.

    Alani AH, Toh CG. Detection of microleakage around dental restorations: a review. Oper Dent 1997; 22(4):173-85.

    Yap AU, Seneviratne C. Influence of light energy dentistry on effectiveness of composite cure. Oper Dent 2001; 26(5):460-6.

    Mc Donald RE, Avery DR, Dean JA. Dentistry for the child and adolescent. 8th ed. USA: Patricia Tannian; 2004. P.344-6.

    Sidu SK. The effect of acid-etched dentin on marginal seal.Quintessence Int 1994;25(11):797-800.

    Ferracane JL. Current trends in dental composites. Crit Rev Oral Bio Med. 1995;6(4):302-18.

    Chaung SF, Jin YT, Liu JK, Chang CH, Shieh DB. Influence of flowable composite lining thickness on class II composite restorations. Opera Dent. 2004;29(3):301-8.

    Mitchell C. Dental Material in Operative Dentistry. 1st ed. London: Quintessence Pub Co; 2008.p.1,17,18.

    França FM, Worschech CC, Paulillo LA, Martins LR, Lovadino JR. Fracture resistance of premolar teeth restored with different filling techniques. J Contemp Dent Pract. 2005;6(3):62-9.

    Rees JS, Jagger DC, Williams DR, Brown G, Duguid W. A reappraisal of the incremental packing technique for light cured composite resins. J Oral Rehabil. 2004;31(1):81-4.

    Belli S, Erdemir A, Ozcopur M, Eskitascioglu G. The effect of fiber insertion on fracture resistance of root filled molar teeth with MOD preparations restored with composite. Int Endod J. 2005;38(2):73-80.

    Roberson TM, Heymann HO, Ritter AV, Periera PNR. Introduction to composite restorations. In: Roberson TM, Heymann HO, Swift EJ editors. Sturdevant's Art and Science of Operative Dentistry. 5th ed. St Louis: Mosby Co; 2006.p.504.

    Donley KJ, Wild TW, Bowen RL, Jensen ME. An in vitro investigation of the effects of glass inserts on the effective composite resin polymerization shrinkage. J Dent Res.1989;68(8):1234-7

    Lazarchik DA, Hammond BD, Sikes CL, Looney SW, Rueggeberg FA. Hardness comparison of bulk-filled/transtooth and incremental-filled/occlusally irradiated composite resins. J Prosthet Dent. 2007;98(2):129-40.

    El-Mowafy O, El-Badrawy W, Eltanty A, Abbasi K, Habib N. Gingival microleakage of class II resin composites with fiber inserts. Opera Dent. 2007;32(3):298-305.

    Hilton TJ, Broome JC. Direct Posterior Aesthetic Restorations. In: Sumitt JB, Hilton TJ, Schwartz RS. Fundamentals of Operative Dentistry: A Contemporary Approach. 3rd ed. London: Quintessence Pub Co; 2006.p.297-8,314,317.

    Boaro LC, Gonçalves F, Guimar?es TC, Ferracane JL, Versluis A, Braga RR. Polymerization stress, shrinkage and elastic modulus of current low-shrinkage restorative composites. Dent Mater. 2010;26(12):1144-50. Epub 2010 Sep 15.

    Krifka S, Federlin M, Hiller KA, Schmalz G. Microleakage of silorane- and methacrylate-based class V composite restorations. Clin Oral Investig. 2011 Sep 27. [Epub ahead of print]

    Zhao D, Botsis J, Drummond JL. Fracture studies of selected dental restorative composites. Dent Mater. 1997;13(3):198-207.

    Manhart J, Kunzelmann KH, Chen HY, Hickel R. Mechanical properties and wear behavior of light-cured packable composite resins. Dent Mater. 2000;16(1):33-40.

    Pisarski H. Fracture toughness testing; [1 screen]. Available at URL: http://www.twi.co.uk/content/kscsw011.html. Accessed June 19, 2009.

    Bonilla ED, Mardirossian G, Caputo AA. Fracture toughness of posterior resin composites. Quintessence Int. 2001;32(3):206-10.

    Tantbirojn D, Versluis A, Cheng YS, Douglas WH. Fracture toughness and microhardness of a composite: do they correlate? J Dent. 2003;31(2):89-95.

    Xu HH, Schumacher GE, Eichmiller FC, Peterson RC, Antonucci JM, Muller HJ. Continuous-fiber perform reinforcement of dental resin composite restoration. Dent Mater. 2003;19(6):523-30.

    Anusavice KJ. Phillips' Science of Dental Materials. 11th ed. St Louis: Saunders; 2003.p.73,93-94.

    Eakle WS. Fracture resistance of teeth restored with class II bonded composite resin. J Dent Res. 1986;65(2):149-53.

    Purk JH, Eick JD, DeSchepper EJ, Chappell RP, Tira DE. Fracture strength of class I versus class II restored premolars tested at the marginal ridge. Standard preparations. Quintessence Int. 1990;21(7):545-51.

    Collins CJ, Bryant RW, Hodge KL. A clinical evaluation of posterior composite resin restorations: 8-year findings. J Dent.

Comparative investigation of fracture resistance of teeth restored with different techniques and composites with different bases
How To Access The File
Related Contents:
Number of pages: 89 Category: Medical Sciences

Dissertation for receiving the degree of Doctor of Dentistry, Dental Materials Research Center Abstract Objective: One of the objectives of this study was to investigate the fracture resistance of the teeth coated with various crown and root restorations. Materials and methods: 60 freshly extracted human premolar teeth were selected and randomly divided into five groups of ...

Number of pages: 73 Category: Medical Sciences

Dissertation for receiving the degree of Doctor of Dentistry Abstract Introduction Considering the importance of milk teeth in creating an ideal occlusion, it is essential to preserve and maintain them due to caries. One of the methods of restoring milk teeth is the use of stainless steel veneers. Maintaining the health of the tissue that supports the teeth is one of the ...

Number of pages: 87 Category: Medical Sciences

Dissertation for Doctorate Degree in Dentistry Abstract The purpose of this study was to compare the microleakage of adhesive total etch and self etch using three methods of Fluid filtration, dye penetration and dye extraction, as well as to determine the statistical relationship between these three methods. Materials and methods In this laboratory study, 72 extracted human ...

Number of pages: 136 Category: Medical Sciences

Dissertation to receive a specialized doctorate degree in dentistry in the field of pediatrics Abstract History and Purpose Traumatic dental injuries are considered one of the most common events in childhood and adolescence. Among these injuries, ovalgen (falling out of the tooth from the socket) is considered a real emergency and requires quick and accurate treatment by a ...

Number of pages: 76 Category: Facilities - Mechanics

Dissertation for Master's Degree in Mechanical Engineering Field: Applied Design Abstract In this thesis, stability analysis of composite beam reinforced with carbon nanotubes on elastic support under axial force is investigated. The distribution of nanotubes is assumed to be uniform[1]. To determine the properties of materials reinforced with nanotubes, the results of molecular ...

Number of pages: 140 Category: Facilities - Mechanics

Master's Thesis in Mechanical Engineering (Applied Design): Abstract of the analysis of leading damage in pin connections of composite materials. The purpose of this research is to analyze the leading damage in pin connections of composite materials. To do this, finite element software ABAQUS and FORTRAN programming have been used. The contact between the composite plate with ...

Number of pages: 104 Category: Computer Engineering

Master's thesis in the field of computer engineering (artificial intelligence) abstract of various image processing techniques are widely used in the field of dentistry. Among these applications, we can mention the identification based on dental images, the detection of dental caries, as well as the identification and examination of dental lesions, which mainly occur around the ...

Number of pages: 64 Category: Medical Sciences

Dissertation to receive a general doctorate, abstract, introduction and purpose, among the banding problems in orthodontics, is the creation of decalcified areas around the bands. On the other hand, during the treatment, the bands are prone to loosening and the cement used must have sufficient strength. Recently, new compounds containing amorphous calcium phosphate (ACP) have ...

Number of pages: 59 Category: Chemical - Petrochemical Engineering

Dissertation for Master's Degree in Chemistry, Chemistry, Abstract: Epoxy resins, which are thermosetting polymers, have properties such as high thermal stability, good adhesion, high chemical resistance, easy molding, and moisture resistance. These resins are used as adhesives, coatings, paints and polymer tools. The most common epoxy resin is prepared from the reaction of ...

Number of pages: 90 Category: Chemical - Petrochemical Engineering

Master's Thesis of Polymer Science and Technology Engineering Abstract Urethane-acrylate resins are of interest due to their low viscosity and flame retardant properties and relatively easy curing. On the other hand, natural fibers with renewable resources, low price, low density and high special properties have a special ability to be used in composites. However, their ...