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bite registration for fixed Prosthodontic restoration

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Techniques and materials used for bite registration
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Interocclusa l Record Prepared by:Botan Barzan Khafaf MSc. Student Supervised by: Raid Fahim Ass.Prof. Hawler Medical University College of dentistry Conservative department
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  • Interocclusal Record Prepared by:Botan Barzan Khafaf MSc. Student Supervised by: Raid Fahim Ass.Prof. Hawler Medical University College of dentistry Conservative department
  • content Definitions. Criteria of choosing material for bite registration. Materials and their properties that used for bite registration. Technique Comparing between some materials in accuracy Conclusion
  • Centric relation
  • Centric Relation After Occlusal Vertical dimension is determined and considered normal. Arch to arch relation. Condyles are in the most middle superior position in glenoid fossae. (1) its a jaw position that should be comfortable for the muscles/nerves/etc. of the TMJ . (2) its a jaw position that can be consistently found regardless of the teeth.
  • Eccentric I.O.R Lateral excursive records: the lateral excursive registration records the lateral excursive maxillomandibular relationship and is performed without occlusal contact. These records are used to set the condylar elements of an arcon and non arcon semi adjustable articulator. Protrusive interocclusal records also evaluated.
  • Centric Occlusion Teeth to teeth relation.maximum intercuspation. Occlusal stop centric occlusion No occlusal stop centric relation When the teeth do not offer vertical and horizontal stability between the arches; an interocclusal record is needed to relate the casts.
  • Classification of tooth-contact patterns Four groups as follows: 1. Cuspid protected occlusion: the contact of canines on the working side. 2. Group function occlusion: contact of canines, premolars, and/or molars, or contacts of premolars and molars on the working side only.
  • Classification of tooth-contact patterns 3. Full balanced occlusion: tooth contact patterns with group function or cuspid protected occlusion on the working side plus multiple tooth contacts of posterior teeth on the non-working side . 4. Others: occlusal patterns other than those described. Contact of incisor teeth, if any, were included in this classification.(Ogawa ,1998 ; Gupta , 2013)
  • Hellman described four ways in which teeth contact 1. surface 2. cusp tip and fossa 3. ridge and groove 4. ridge and embrasure. 138types and 90% of the total units actually make exact contact in dentitions with normal occlusion.
  • Interocclusal Record TMJ Dentition Periodontal tissue
  • According to Dawson criteria for accuracy in making interocclusal records : The recording material must not cause any movement of teeth or displacement of soft tissues. The recording material must fit casts as accurately as it fits the teeth intra-orally. The accuracy of the jaw relation record should be checked in the mouth and on the casts.
  • Sensitivity and Reliability Depend on : Thickness . Strength . Elasticity of the recording materials. Oral environment . Clinicians interpretation . (Sharma et al ,2013)
  • Accuracy of an interocclusal record Influenced by: Material properties. Recording technique. Reliability of the mandibular position influenced by the occlusal contacts . Muscular action. Tissue changes within the joints . (Ghazal M et al, 2008; Michalakis KX et al, 2004)
  • Methods are used for the evaluation of occlusal relationships: 1- Quantitative method : evaluating occlusal relationships, the sequence and density of the contacts can be differentiated. Quantitative measures for determining occlusal relationships: Photo-occlusion T-Scan system (Sharma et al ,2013)
  • Methods are used for the evaluation of occlusal relationships. 2- Qualitative method: Density of the contacts according to the darkness of the marks, this is not a precise criterion for evaluation. Wax, articulating paper. foils. Silk strips .ect (Sharma et al ,2013)
  • Types of Interocclusal Records Basically, there are two main categories of interocclusal registration: Centric interocclusal records Eccentric interocclusal records. (Sharma et al ,2013)
  • Indications for Interocclusal Records 1-If the patient has an adequate number of teeth and a stable intercuspal position, no signs and symptoms of trauma to the occlusion and the goal of treatment is to maintain pre-treatment intercuspation and occlusal vertical dimension (OVD), Most accurate method of articulation is to occlude opposing casts by hand, without intervening bite registration material. Recording material placed between teeth in this case often prevents casts from maximal intercuspation and an interocclusal record is registered at an increased OVD. Mounting casts in the maximum intercuspal position (MIP) facilitates treatment . (Saluja B& Mittal D ,2013)
  • Indications for Interocclusal Records 2-If the planned restorations involve terminal teeth in the arch An interocclusal record is needed as there is insufficient horizontal stability of the casts for hand articulation and mounting. For opposing casts to occlude accurately, a tripod of vertical support and horizontal stability must exist between the casts. To ensure that there are sufficient numbers of occluding teeth to mount working and opposing casts in MIP. 3-When terminal teeth are prepared for crowns or fixed partial dentures and the third leg of the tripod is lost. the dentist must fabricate an interocclusal record to recapture the lost leg and create a tripod of vertical support to mount casts accurately. (Saluja B& Mittal D ,2013)
  • THE ACCURACY OF TWO METHODS OF OCCLUSAL REGISTRATION INVOLVING TERMINAL ABUTMENTS AN INVIVO STUDY (Deivanai et al, 2013) Articulation I - Pre operative casts Articulation II - Inter occlusal record with centric stop. Articulation III Iner occlusal record without a centric stop. Within the limitations of the present study; a) Presence of Interocclusal records results in an increase in vertical discrepancy. b) Presence of centric stop was found to cause greater discrepancy than without centric stop. Limitations;more number of samples . -techniques to limit control of interocclusal materials to flow over the centric stop.
  • INTEROCCLUSAL RECORDS IN PROSTHODONTIC REHABILITATIONS (Prasad et al,2012) When the distal most molar is prepared as the abutment for three to five unit posterior FPD. 1-uses conical stops, prepared in the enamel of the abutment or made of composite or a metal core covered with composite, to maintain the vertical dimension of occlusion and to act as the third point of reference for a stable occlusal 8 relationship when occluding a definitive casts. Materials generally used are polyether, silicone or acrylic resin. drawback; ;forces that either displace soft tissue or tilt the denture bases.
  • When the distal most molar is prepared as the abutment for three to five unit posterior FPD. 2) stabilized baseplate technique for making interocclusal records which provided a means to record centric and eccentric jaw registrations that are stable intraorally and can also be transferred accurately to the working model. drawback; ;forces that either displace soft tissue or tilt the bases.
  • 3) acrylic resin anterior stop to hold the desired vertical dimension of occlusion.procedure for making an interocclusal record without the use of record bases. Base plate Wax then relined by ZOE.
  • Dawson Technique (Bimanual manipulation technique). anterior- jig programmer Lucia jig Leaf Gauge
  • (Ericsson et al ,2002) 7093% of the variation of the positions of the mounted casts Clinical factors and clinical variation influencing the reproducibility of interocclusal recording methods mandibular positions ( 011%) Materials used (0 29%) clinical variation (Remaining %) (intercuspal position (IP) retruded contact position (RCP) two different types of waxes One FPD One RPD One CD record rims vinyl polysiloxanes one irreversible hydrocolloid
  • Materials Used for Interocclusal Records Limited resistance before setting to avoid displacing the teeth or mandible during closure. Minimal dimensional change It should be easy to manipulate . No adverse effects on the tissues involved in the recording procedures . It should accurately record the incisal and occlusal surfaces of teeth . It should be verifiable. Over clinically reasonable time periods, they must have solidity to retain the shape and strength when dental casts are articulated.
  • Materials 1. Bite registration Wax. 2. zinc oxide containing pastes (eugenol containing and non eugenol pastes). 3. Waxed articulating paper. 4. Modeling compound. 5. Acrylic resin .elastomeric materials . 6. Alginate Impression Material Index 7. Mylar Paper / Shimstock films. 8. Polyether Silicon Impression Bites. 9. Silicon Putty Material. 10. Additional silicon soft injectable 11. Typewriter Ribbon. 12. Transparent Acetate Sheet. 13. Silk Strips. 14. Foil. 15. High Spot Indicator. 16. Occlusal Sprays. 17. Photo-Occlusion. 18. Occlusion Sonography. 19. T-Scan. 20. Pressure Sensitive Films. 21. combination of some materials.
  • Bite-registration wax It is the most versatile ,the reason is its easy manipulation and when softened uniformly and remains soft for an adequate working time. The flow of these materials at 37.5 C is from 2.5% to 22% which it is susceptible to distortion on removal from the mouth. Other wax 28 gauge baseplate wax also used but additional silicon and polyether have replaced waxes for bite-registration. (Powers & Wataha ,2013)
  • Bite Registration wax Therefore, it has been classified as most inaccurate material among the interocclusal records studied? it is dimensionally inaccurate. it has a high coefficient of thermal expansion high resistance to closure. Distortion of wax during removal is also very common. The flow ranges from 2.5% to 22% at 37.5 C , due to release of internal stresses. lead to inaccuracies while registration is made. (Powers & Wataha ,2013)
  • Corrective wax or impression wax It is not widely used because of instability, instead elastomeric impression material used . Metallized wax much more accurate than non-metallized wax as the addition of metal particles (aluminum) to the modeling wax make it more conductive which may lead to variation in the accuracy of the record. (Soratur SH ,2002)
  • Impression plaster Impression plaster is basically plaster of Paris with modifiers. Modifiers accelerate setting time and decrease setting expansion. Records of impression plaster are accurate, rigid after setting, and do not distort with extended storage. Disadvantages; It is difficult to handle because the material is fluid and unmanageable prior to setting. The final interocclusal record is brittle. (Pence BA & Baum L, 1994).not used now (Sharma et al ,2013)
  • Alginate Imp. Material index IF left on the bench for as short a time as 30 minutes may become inaccurate enough to require remaking the impression. Even if the impression stored for more than 30 minutes in air were immersed in water, it would not be feasible to determine when the correct amount of water had been absorbed. (Sakaguchi RL & Powers JM,2013)
  • Modeling compound (Saluja BS & Mittal D,2013 ) Modeling compound, which becomes rigid upon setting, has been used to fabricate segmental interocclusal records. Disadvantages: Flow of the material over axial surfaces of natural teeth and over soft tissues, which invites errors in repositioning working casts within the bite registration. Abrasion of working cast dies during mounting and subsequent removal of the record.
  • Zinc oxide eugenol paste Fluidity before setting so it offers minimal resistance with mandibular closure and becomes rigid after it sets finally. But,zinc oxide eugenol pastes have a lengthy setting time, significant brittleness; they stick to the teeth and have unreliability to reuse. As it sets by chelation reaction, by - products formed may undergo evaporation leading to dimensional change. Vital portions of the record can be lost through breakage on removal from the mouth.Unless trimmed, flash around the teeth can prevent the accurate seating of casts.Therefore, zinc oxide eugenol or resin was added to wax impression in a very thin layer to improve poor detail transfer and displacement of wax. (Sharma et al ,2013)
  • Acrylic Resin The most frequent application of acrylic resins for interocclusal records is in the fabrication of single stop centric occlusion records. Acrylic resin is both accurate and rigid after setting. Disadvantages : Dimensional instability due to polymerization shrinkage. Rigidity of the material can damage plaster cast and dies during mounting on the articulator. (Sharma et al ,2013)
  • (Luxabite , DMG,USA)
  • Elastomers for IOR: Least error among the materials studied. They are easy to manipulate and offer little or no resistance to closure. Set to a consistency that makes them easy to trim without distortion, and accurately reproduce tooth details. Furthermore, among the elastomers, addition silicones exhibit least amount of distortion. The excellent dimensional stability of addition silicones is attributed to the fact that it sets by addition polymerization reaction. Therefore, no by-products and no loss of volatiles occur in addition silicones. Dimensional stability, accuracy and elastic recovery, with short working time.
  • Elastomers Disadvantages : Any compressive force exerted on these materials during mounting procedures may cause inaccuracies during mounting of the casts( Spring action). The spring action found in these materials causes the articulated cast to open in centric relation position. Thus, the records should be trimmed and carefully seated over the occlusal surface to minimize the negative spring action. cost compared to others. Table 1: Mechanical and phsical properties of elastomeric impression materials. (Powers & Wataha ,2013).
  • Polyether The advantages are accuracy, have some property close to additional silicon, fluidity and minimal resistance to closure, can be used without a carrier. Disadvantages ; Limited dimensional stability over time.(1&7 days 0.3%) Aromatic sulfonic acid irritate oral soft tissue. Poor taste . Resiliency and accuracy may exceed the accuracy of the plaster casts. Both of these factors can interfere with the placement of the plaster cast into the recording medium during mounting procedures. The records are trimmed to remove excess material and preserve only the teeth indentations to avoid distortions.
  • Additional Silicon Vinyl polysiloxane (VPS). No volatile by product(alcohol or water) so more dimensionally stable than condensation. Auto mix , dynamic mix and monophase.soft medium and putty consisitency Dimensional change 0.1% in 24 hour (very low). Permanent deformation 0.2 %(99.8% elastic recovery). Short working time . (Powers & Wataha ,2013)
  • Virtual CADbite Registration ,Ivoclar vivadent , Liechtenstein Short working time, Working time after mixing at 23C max. 30 sec. Minimum time in mouth min. 45 sec. Detail reproduction 2 m Shore D hardness (1h after setting) 32 3 (Durometer Shore Hardness Scale).extra soft.
  • Bite registrations for CAD/CAM procedures There are digital impression taking procedures, which are employed in conjunction with the computer-aided design/computer-aided manufacturing (CAD/CAM) of tooth restorations. Digital impressions are taken either : -Of the model in the dental lab. -Directly in the mouth at chairside using an intraoral scanning device or camera. In order to determine the occlusal relationship, an antagonist bite registration is required. Being able to directly capture images of this bite record with a scanning device or camera without having to apply a contrast medium.
  • scannable bite registration materials StoneBite Scan from Dreve. Metal-Bite from R-Dental . Kanibite Scan from Kaniedenta . Virtual CADbite from Ivoclar.no contrast medium required. All of these materials are vinyl polysiloxanes. Saves considerable time and eliminates a possible source of error.
  • Table-2 : Properties of different bite-registration material according to manufacturing Company.(http://www.realityesthetics.com)
  • Photo-Occlusion In a photo occlusion system, a thin photoplastic film layer is placed on the occlusal surface of the teeth; the patient then is asked to occlude on the film layer for 10 to 20 seconds. The film layer is removed from the mouth and inspected under a polariscope light. This technique is reported to be difficult to apply. The technique was found to be highly reproducible.(introduced in 1963)
  • T-Scan 1984 The development of a prototype computerized occlusal analysis (T-Scan; Tekscan Inc,USA) was reported by Mannes et al. The T-Scan instrument was designed to examine and record occlusal contacts by computer analysis of information from a pressure-sensitive film. The T-Scan system digitally records both the location and timing of tooth contacts. Time moments are defined as the sum of distances of the tooth contacts in millimeters from the x axis of the occlusal plane multiplied by their relative time value (1-sec) and divided by the sum of the onset times.
  • When an operator properly uses this technology, mark size, mark color-depth, donut-shaped halo contacts, as well as other color and mark appearance characteristics, are ignored as force indicators and used only as contact locators. (Kerstein RB ,2008). There is a decrease in sensitivity of the indicator film with repeated use. The anatomic circumstances did not influence the sensor's sensibility or reproducibility of new TScanIII HD system (Martin et al, 2014) .
  • Occlusion Sonography Dental Sound Checker 1960 One commercial device was produced in the mid 1980s called (Yoshida, Tokyo, Japan). The device, based on the principles put forth by Watt, was developed to evaluate occlusal contact sound paterns during closure in an attempt to detect occlusal disturbances. (Klifune et al ,1985) measured the duration of the occlusal sound in a single subject before and after occlusal adjustment and reported a clear decrease in the duration of the occlusal sound with adjustment
  • Typewriter Ribbon (Ziebert and Donegan ,1979 ) used typewriter ribbon to mark supra contacts or occlusal interferences in their patients for occlusal adjustments. Interferences were marked with typewriter ribbon and contacts verified with 0.00l-inch shim stock. The adjustment procedure basically started with( Schuyler, 1935) following the M. U.D.L. rule for the retruded position, the B.U.L.L. rule for the retruded position , the B.U.L.L rule for the working movement, and the D.U.M.L. rule for protrusion. Nonworking interferences were eliminated so as to maintain at least one centric stop on each tooth. (Sharma et al ,2013)
  • Transparent Acetate Sheet (Davies et al , 2002) described a clinical method termed the occlusal sketch technique as a means of recording occlusal contacts. The sketch consists of an acetate sheet on which a schematic representation of the teeth is drawn, including the occlusal surfaces of the posterior teeth, the palatal surfaces of the maxillary anterior teeth and the labial surfaces of the mandibular anterior teeth. The same authors concluded that this technique demonstrated interoperator and intraoperator reliability in recording occlusal contacts in vitro. The aim of the occlusal sketch technique is to provide a simple and reliable means of recording and transferring information about the location of marked occlusal contacts. It may also be used by the technicians to verify occlusal contacts when articulating casts and fabricating indirect restorations . (Sharma et al ,2013)
  • Wax Articulation Paper The color coating of many articulating papers consists of waxes, oils and pigments, a hydrophobic mixture which repels saliva (hydrophilic) consisting mainly of water. High spots can be detected easily as dark marks and contacts as light marks. Articulating paper come sin strips and horse shoe shaped sheets (Bausch articulating paper Inc, Nashua, NH, USA). When grinding selectively it should be noted that only dark colored spots should be ground. The major disadvantages : can be easily ruined by saliva, are thick, and they have a relatively inflexible base material; all of these factors result in a greater number of pseudo contact markings .
  • Wax Articulation Paper Few manufacturers have produced articulating films with an additional emulsifier (Bausch articulating paper Inc, Nashua, NH, USA) which gives these films certain bonding properties on moist occlusal surfaces. They have added special bonding agent- transculase (Bausch articulating paper Inc, Nashua, NH, USA), or wetting agents like lecithin .to articulating paper coating. The first test is made with blue articulating paper (200microns). Spots are immediately evident. The bonding agent, transculase, is also transferred as a fine coating. The next step is to take a thin film (preferably red, 8microns) because of its intensity and excellent contrast with blue . The color transfer of these film are considerably improved with the help of transculase coating.
  • Silk Strips Some researchers have stated that silk strips are the best material for indicating occlusal contacts. Articulating silk is made from high quality natural silk (Bausch articulating silk, 80 microns, Bausch articulating paper Inc, Nashua, NH, USA). Natural silk consists of so-called fibrils, a tube-shaped protein structure which, because of its composition, has an extremely high color reservoir capacity. This silk is highly tear-resistant and, because of its low thickness and good flexibility, adapts perfectly to cusps and fossae. The marking of silk is extremely precise. Because of their texture, soft indicator materials do not produce pseudo contact markings. However, silk strips can lose their marking abilities when their stain components are dried, and they also can be ruined by saliva. It is therefore advisable to store them in a cool, closed environment.
  • High Spot Indicator (Arti-spot, Bausch articulating paper Inc, Nashua, NH, USA It is a liquid contact color) which is applied to the test surface with a brush . The solvent evaporates in seconds, leaving a thin film (3 microns thick). Every contact destroys skin color exactly at the point of contact. The base material then shines through and high spots can easily be detected. It can also be used to test for high spots on highly polished occlusal surfaces such as gold or ceramic. The food dye contained in the solvent is completely safe. The layer can easily be removed after use with hot water or alcohol.
  • Occlusal Sprays (Arti-Spray, Bausch articulating paper Inc, Nashua, NH, USA) These are universal color indicator to test occlusal contacts. They are easy to administer and leaves a thin colored film which can easily be removed with water, leaving no trace of residues. They are applied at a distance of 3-5 cm onto the occlusal surface. When testing occlusion all contact points will be immediately visible. These are available in colors: red, blue, green and white.
  • Pressure Sensitive Films 1987 A newer but essentially similar device has been introduced (Dental Prescale, Fuji Film, Tokyo, Japan). This device also records the location and force of contacts with the force sensitive film. evaluated the reliability of this device for occlusal force measurement both on a subject and on casts. They reported the linear relationship between the applied and measured loads. The primary limitation of the contact sensor and the pressure sensitive film device is that the recording medium is far too thick and results in heavier contacts on the posterior teeth than the anterior teeth. Further, this sensor thickness disturbs the persons finding attempts to close into the intercuspal position.
  • A clinical sudy: Polyether , Polyvenyl siloxane and wax were tested to evaluate the reproducibility of horizontal condylar registration on both types of semi adjustable articulators. (Sharma et al ,2011) Fully adjustable articlators Coefficient of Thermal expansion ,greater resistance during closure and cannot be uniformly heated. Evaluation of the reproducibility of horizontal condylar registration on both types of semi adjustable articulators. (Sharma et al ,2011) Polyether(Ramitec) PVS(Jetbite) Wax(aluwax) minimum minimum -Wide variation -Unreliable( lateral &protrussive movements) -Greatest vertical discrepancy
  • Evaluation of different materials recording free- end(PagnanoI V et al, 2005) acrylic resin base + wax acrylic resin plate + alginate acrylic resin base + wax + ZOE acrylic resin base + wax + Duralay(Acrylic) condensation silicone. elastomers may suffer distortion at the time of cast joining, due to the compressive force generally exercised to maintain the casts in position From less distortion
  • ,, (Anup G et al ,2011) Polyvinylsiloxane Zinc oxide eugenol Aluwax Dimensional Stability statistically but not clinically 1 2 3 Accuracy 1, 24, 48, and 72 h 1 2 3 Surface Hardness after 24 hrs No statistical difference Surface Hardness after 48 hrs 1 2 3
  • References -Anup G, Ahila C and VasanthaKumar M , 2011 , Evaluation of Dimensional Stability, Accuracy and Surface Hardness of Interocclusal Recording Materials at Various Time Intervals: An In Vitro Study , J Indian Prosthodont Soc. Mar 2011; 11(1): 2631. -Ashu Sharma, G R. Rahul, Soorya T. Poduval, Karunakar Shetty, Bhawna Gupta and Varun Rajora ,2013 . History of materials used for recording static and dynamic occlusal contact marks: a literature review . J Clin Exp Dent. Feb 2013; 5(1): e48e53. -Deivanai EM,Ali SA, Karthigeyan S, Madhan R, Giri C,and Maran SC, 2013 . COMPARATIVE EVALUATION OF THE ACCURACY OF TWO METHODS OF OCCLUSAL REGISTRATION INVOLVING TERMINAL ABUTMENTS AN INVIVO STUDY . Pakistan Oral & Dental Journal Vol 33, No. 1.P 212-217. -Eriksson A, ckert-Eriksson G , Lockowandt P & Eriksson O , 2002.. Clinical factors and clinical variation influencing the reproducibility of interocclusal recording methods .B Dent J 192, 395 - 400 (2002) -Gupta A, Shenoy VK, Shetty TB and Rodrigues SJ. Evaluation of pattern of occlusal contacts in lateral excursion using articulating paper and shim stock: An in vivo study. J Interdiscip Dentistry 2013;3:109-13. -Martins DS, Jorge M, Jose F; da Fonseca R, Andr J, Nicolau G and Miguel P , 2014 , In vitro study on the sensibility and reproducibility of the new TScanIII HD system , Estomatol Med Dent Cir Maxilofac,55:14-22 . - PagnanoI V , BezzonI OL , de MattosI M ;, RibeiroI RF and TurbinoI ML , 2005 .Clinical evaluation of interocclusal recording materials in bilateral free end cases. Braz. Dent. J. vol.16 no.2 Ribeiro Preto May/Aug. 2005 -Powers JM, Wataha JC, 2013 . Waxes; Dental Material properties and maninupilation.Elsevier. P128. -Prasad KD, Prasad BR and Mihra D, 2012. REHABILITATIONS - MATERIALS AND TECHNIQUES A LITERATURE REVIEW. NUJHS Vol. 2, No.3, September 2012.P 54-60 -Saluja BS, Mittal D. Interocclusal records in fixed prosthodontics. Indian J Oral Sci 2013;4:120-4 . -sakaguchi RL, Powers JM, 2013.craigs Restorative dental material. -Soratur SH ,2002 .Waxes, Essentials of dental material, P 388. - Sharma LA , Azhagarasan NS, Shankar C , and Sharma A ,2011 . Comparative study of the effect of three different interocclusal recording materials on reproducibility of horizontal condylar registrations in two different semi- adjustable articulators: A clinical study .Int J Pros & Res Dent. 1(3):155-162. - Takai A, Nakano M, Bando E, Hewlett ER. Evaluation of three occlusal examination methods used to record tooth contacts in lateral excursive movements. J Prosthet Dent. 1993;70:5005. http://www.realityesthetics.com/images/OtherMedia/categoryintros/BiteRegistrationMaterials-intro.pdf

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