2. 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
4. 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) it’s a jaw position that should be comfortable for
the muscles/nerves/etc. of the TMJ .
• (2) it’s a jaw position that can be consistently found
regardless of the teeth.
5. 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.
6. 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.
7. 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.
8. 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)
9. 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.
11. 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.
12. Sensitivity and Reliability
• Depend on :
• Thickness .
• Strength .
• Elasticity of the recording materials.
• Oral environment .
• Clinician’s interpretation .
(Sharma et al ,2013)
13. 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)
14. 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)
15. 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)
16. Types of Interocclusal Records
• Basically, there are two main categories of
interocclusal registration:
• Centric interocclusal records
• Eccentric interocclusal records.
(Sharma et al ,2013)
•
17. 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)
18. 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)
19. 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.
20. 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.
21. • 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.
22. • 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.
24. (Ericsson et al ,2002) 70–93% of the variation of the positions of the
mounted casts
Clinical factors and clinical variation influencing the reproducibility of
interocclusal recording methods
mandibular positions
( 0–11%)
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
25. 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.
27. 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)
28. 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)
29. 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)
30. 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)
31. 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)
32. 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.
33. 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)
34. 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)
36. 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.
37. 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).
38. 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.
39. 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)
40. Virtual CADbite Registration ,Ivoclar vivadent , Liechtenstein
• Short working time, Working time after mixing at
23°C max. 30 sec.
• Minimum time in mouth min. 45 sec.
• Detail reproduction 2 μm
• Shore D hardness (1h after setting) 32 ± 3
(Durometer Shore Hardness Scale).extra soft.
41. 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.
42. 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.
45. Table-2 : Properties of different bite-registration material according to manufacturing
Company.(http://www.realityesthetics.com)
46. 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)
47. 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.
48. • 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 T‐Scan®III HD
system (Martin et al, 2014) .
49. 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
50. 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)
51. 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)
52. 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 .
53. 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.
54. 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.
55. 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.
56. 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.
57. 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.
58. • 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
59. 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
60. • ,,
(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
62. References
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Interocclusal Recording Materials at Various Time Intervals: An In Vitro Study , J Indian Prosthodont Soc. Mar 2011; 11(1):
26–31.
-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): e48–e53.
-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, Öckert-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.
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reproducibility of the new T‐Scan®III HD system , Estomatol Med Dent Cir Maxilofac,55:14-22 .
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recording materials in bilateral free end cases. Braz. Dent. J. vol.16 no.2 Ribeirão Preto May/Aug. 2005
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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.
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- 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.
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contacts in lateral excursive movements. J Prosthet Dent. 1993;70:500–5.
• http://www.realityesthetics.com/images/OtherMedia/categoryintros/BiteRegistrationMaterials-intro.pdf