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Surveying/ dentistry dental implants

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Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.


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  • 1. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  • 2. www.indiandentalacademy.com
  • 3. What is Dental surveyor? Dental surveyor: A dental cast surveyor has been defined as an instrument used to determine the relative parallelism of two or more surfaces of the teeth or other parts of the cast of a dental arch. Dr. A.J. Fortunati is thought to be the first person to employ a mechanical device to determine the relative parallelism of tooth surfaces. The first such device to be produced commercially, the Ney instrument, was made available in 1923; it remains the most widely used surveyor in the dental field. The Wills surveyor by Jelenko is second most widely used. www.indiandentalacademy.com
  • 4. What are aims and objectives of surveying? 1.Determine the most advantageous path of insertion/ removal for the RPD. 2.Locate proximal tooth surfaces that are or can be made parallel to act as guiding surfaces. 3.Locate and measure recesses or undercuts for mechanical retention. 4.Identify areas of potential hard or soft tissue interferences. 5.Determine a path of insertion/ dislodgement consistent with esthetic requirements. www.indiandentalacademy.com
  • 5. 6. Dilineate the height of contour of the abutment teeth and identify the areas of undercut that must be avoided, reduced, blocked out or preserved. 7. Help in planning restorative procedures . 8. Record the most ideal cast position for future reference. 9. Establish a formal plan for RPD design and the required mouth preparation. www.indiandentalacademy.com
  • 6. What are the parts of dental surveyor? 1. A level platform that is parallel to the bench top and on which the cast holder is moved. 2. A vertical arm that supports the superstructure. 3. A horizontal arm that extends at a right angle form the vertical column from which extends the other part of the superstructure, the surveying arm. In the Ney surveyor the horizontal arm is fixed, whereas in the Wills instrument it may revolve horizontally around the vertical column. 4. A surveying arm drops vertically from the horizontal arm. The surveying arm is capable of movement in a vertical direction. In the Wills surveyor the surveying arm is spring loaded.www.indiandentalacademy.com
  • 7. 5. A cast holder, or surveying table, to which the cast to be studied is attached. The table equipped with a clamp to lock the cast in place, is mounted on the ball and socket joint that permits the cast to be oriented in various horizontal places so that the axial surfaces of the teeth as well as other areas of the cast can be analyzed in relation to the vertical plane. 6. An analyzing rod or paralleling tool. This tool contacts the convex surface of the object being studied in the same way a tangent contacts a curve. In this way, the parallelism of one surface to another may be determined.www.indiandentalacademy.com
  • 8. 7. Additional tools that may be attached to vertical surveying arm and used in conjunction with the surveyor a) Undercut gauges: These gauges are used to identify the specific amount and location of desired retentive undercut on the surface of the abutment tooth. b) Wax knife: This instrument is used in late stages of removable partial denture construction to eliminate or block out areas of undesirable undercuts with wax on the cast before the framework is made. c) Carbon marker: The marker may be used to scribe the survey line and to delineate an undercut area of the soft tissue or ridge www.indiandentalacademy.com
  • 9. What are the types of surveyors? Types of Surveyors 1. Ney Surveyor 2. Jelenko Surveyor 3. Williams Surveyor 4. Retentoscope Surveyor 5. A 2000 – Buchnann Surveyor 6. Micro analyzor 7. Stress – O-Graph 8. Austenal Surveyor 9. Optical surveyor 10. Computerized surveyor 11. Ticonium Surveyor 12. Intra Oral Surveyor www.indiandentalacademy.com
  • 10. Ney Surveyor Jelenko Surveyor 1. Horizontal arm is fixed 1. Horizontal arm is movable 2. Vertical arm is retained by friction 2. Vertical arm is spring mounted 3. The shaft remains in any vertical position until again it is moved 3.Vertical arm when released returns to its original position. It should be held against spring tension 4. Cast table is moved around surveyor platform 4.Cast table is fixed with the magnet in the surveyor plat form Difference between Ney and Jelenko surveyor www.indiandentalacademy.com
  • 11. www.indiandentalacademy.com
  • 12. Retentoscope: It is equipped with a gauge to provide exact determination of the undercut being used and so that it makes it possible to produce balanced retention The cast attached on the table can be raised and lowered vertically and eliminates the need for movement in the vertical rod. www.indiandentalacademy.com
  • 13. Williams surveyor: In this table is adjustable to any desired tilt and that degree of inclination can be recorded for positioning the cast at any time. The distinct advantage of this table over universal tilt table is that the center of rotation always remains constant.www.indiandentalacademy.com
  • 14. 2000 Buchnann surveyor: It is used for the placement of precision attachment parallel to the path of insertion. Ticonium Surveyor: Is one of the modern instruments for surveying the dental cast. The marking point will make vertical line on the abutment tooth until the desired depth of infra bulge area has been reached. www.indiandentalacademy.com
  • 15. Microanalyzer: This is a somewhat more sophisticated instrument than the previous ones and is capable of measuring the amount of undercut electronically in millimeters. www.indiandentalacademy.com
  • 16. Stress-o-graph: It consists of two vertical holders. One for measuring the undercut and one for measuring the survey line. This is more elaborate instrument than either the Ney or the Jelenko instrument. www.indiandentalacademy.com
  • 17. Intra Oral surveyor: “Intra oral surveyor” is described for checking tooth preparation of abutment teeth for fixed or removal partial dentures. The device quickly and accurately indicates the planned path of insertion of the prosthesis intra orally and serves as a visual guide during the preparation of the teeth. Aids the dentist in evaluating tooth preparation before making a final impression. www.indiandentalacademy.com
  • 18. This intra oral surveyor provides an inexpensive, practical and readily available method for producing optimal tooth preparation for fixed and removal partial dentures. Optical Surveyor Cast can be surveyed by parallel light instead of the vertical rod a) Parallel light beams are produced by light bulbs with small dense filaments and condenser lenses contained in a box. b) The beams are made parallel with the vertical rod of the conventional surveyor by fixing the box to an iron bar. www.indiandentalacademy.com
  • 19. c) The cast is placed on the table and surveyed in a dark room using parallel light beam. d) The survey line is the border of the bright and dark zones – the line where the light beams are tangent to the cast creates a shadow e) By tilting the table to establish various paths of insertion, undercuts and survey lines may be inspected without drawing on the cast. f) After securing the most favorable path of insertion, the table of the surveyor is locked and survey lines are marked with lead marker.www.indiandentalacademy.com
  • 20. What is diagnostic survey? The diagnostic cast must be surveyed before the treatment plan for the patient can be formulated. For example, the relative parallelism of the abutment teeth must be analyzed to learn whether modification of the tooth surfaces by either contouring the enamel surfaces or by placing a restoration if required. Soft tissue contours must also be studied to determine what effect they may have on the partial denture that is being planned. Undercuts in the soft tissue areas may require surgical removal before the prosthesis will go to place in the mouth. www.indiandentalacademy.com
  • 21. The position of the cast being studied can be changed on the surveying table to allow the designer to analyze what effect this changing the tilt will play on the relative parallelism of the structures. Thus if the anterior of the cast is lowered, the cast is said to have an anterior tilt if the posterior is lowered, the cast has a posterior tilt if the right side is lowered as viewed from the rear, the cast has a right tilt and if the left side is lowered, a left tilt. The surveyor is also used to scribe the survey line on the teeth after the final tilt of the cast has been determined. The significance of the survey line is that all rigid components of the partial denture must be kept occlusal to it. Normally only the terminal third of the retentive clasp arm is placed gingival to the survey line.www.indiandentalacademy.com
  • 22. What are the procedures to be followed during diagnostic survey? Surveying the diagnostic cast: a). The cast is placed on the surveying table with the occlusal surface parallel to the horizontal plane. b). The analyzing table is initially given an anteroposterior tilt, then left and right lateral tilt and analyzed in each position. www.indiandentalacademy.com
  • 23. c). The degree of tilt is altered while the operator looks for the maximum number of parallel surfaces which may act as guides during insertion of the denture, yet at the same time offer resistance to displacement of the denture during function. d). Once analysis is complete, a note is made of the results of the various possible tilts and the analyzing rod is exchanged for an undercut gauge, there are 3 gauges, each with specific use, 0.01” for cobalt chromium; 0.02” cast gold alloy and 0.03” wrought alloy clasps. www.indiandentalacademy.com
  • 24. e). The teeth and tissue are re-analyzed using an undercut gauge. f). Final analysis is carried out bearing in mind the principle of denture design. Once the path of insertion has been decided the surveying table is locked in position. g). Finally tripoding is carried out on the diagnostic cast. www.indiandentalacademy.com
  • 25. What is tilt? Why tilt should be given? Tilt is referred to as ‘changing the long axis of each tooth relative to the horizontal plane’. Tilting is used to obtain the most advantageous path of insertion. Tilting may be used to increase desirable undercuts and to decrease undesirable undercuts. Through tilting, it is possible to increase the undercuts on one side of the tooth while decreasing them on the other side of the tooth. Thus it is remember that while tilting one must examine the effect of any tilt to establish a more desirable undercut on other teeth involved in the design. Tilting can also be used to distribute available undercuts to produce more uniform retention throughout the available teeth.www.indiandentalacademy.com
  • 26. Tilting is also used to develop a path of insertion that will permit the most effective use of an anterior space for replacement. Tilting can also minimize unfavorable undercuts both on the teeth and soft tissues to facilitate better position of major and minor connectors. It should be remembered that if a cast does not have usable undercuts, tilting in it would not produce them. www.indiandentalacademy.com
  • 27. Basic cast tilts The basic position or tilt of the cast on the surveyor should be the horizontal tilt or zero degree tilt. In the horizontal tilt, occlusal surfaces of the teeth are at or nearly parallel to the horizontal plane. This is the standard reference position from which further tilts originate. The four basic tilts from the horizontal or reference position are 1.The anterior tilt in which the anterior teeth are tilted downward. 2.The posterior tilt in which the posterior portion of the cast is tilted downward. 3.The right lateral tilt in which the right portion of the cast is tilted downward. 4. The left lateral tilt in which the left portion of the cast is tilted downward. www.indiandentalacademy.com
  • 28. In most situations the tilt to be selected will be at or near the horizontal tilt with minor modifications in one direction or another to optimize certain undercuts. It must be remembered that if cast does not have the usual undercuts tilting in it would not produce it. www.indiandentalacademy.com
  • 29. What is survey line? It is the line which is marked on the abutment tooth by the surveyor spindle to indicate its greatest circumference in a given horizontal plane. Significance of the survey line is that all rigid components of the partial denture must be kept occlusal to it. Normally only the terminal third of the retentive clasp arm is placed gingival to the survey line. The survey line also helps to locate areas of undesirable tooth undercut that must be avoided or eliminated by contouring or placing restorations on the teeth. Survey line divides the tooth into Supra bulge and Infra bulge area. The area occlusal to the survey line is supra bulge area and the area gingival to the survey line is infra bulge area.www.indiandentalacademy.com
  • 30. How do you classify survey lines? According to Blatterfein, survey lines can be divided into 1. High survey Line 2. Medium Survey Line 3. Low Survey line 4. Diagonal Survey Line www.indiandentalacademy.com
  • 31. High Survey Line: High Survey line is found near the occlusal surface of a tooth often being parallel to the gingival margin. It results from abnormal inclination of the tooth and is frequently found on the lingual surfaces of the lower teeth and buccal surfaces of the upper teeth. www.indiandentalacademy.com
  • 32. Medium Survey Line: Medium Survey line is situated across the center of the tooth and exhibits a slight occlusogingival incline from the near zone to the far zone. www.indiandentalacademy.com
  • 33. Low Survey Line: Low Survey Line is situated close to and parallel to the gingival margin. It frequently occurs as a result of marked inclination of the tooth and may also occur on conically shaped tooth. www.indiandentalacademy.com
  • 34. Diagonal Survey Line: Diagonal Survey line travels diagonally from near the occlusal surface in the near zone to the gingiva in the far zone. www.indiandentalacademy.com
  • 35. Ney classification of survey lines: 3 basic survey lines are described along with appropriate clasp for each. Class I: Survey line runs diagonally across the tooth surface. The type of clasp indicated is occlusally approaching cast clasp with terminal third engaging the undercut. www.indiandentalacademy.com
  • 36. Class II: Survey line also runs diagonally across the tooth surface but as a mirror image of Class I line. Here a gingivally approaching clasp arm is suggested. www.indiandentalacademy.com
  • 37. Class III: Survey line is parallel to the occlusal surface and lies just below it. www.indiandentalacademy.com
  • 38. What is the influence of survey line in designing the direct retainers and path of insertion and removal? High survey line A wrought wire is the clasp of choice in an occlusally approaching clasp design. Such an arm is brought immediately below the survey line and greater part of its length engages in the undercut. However, the bracing arm should be rigid. Other clasp arms which may be used include the Back action clasp and the ring clasp. www.indiandentalacademy.com
  • 39. Back action clasp - the portion of the arm lying on the non-undercut surface is above the survey line and is rigid by virtue of its thickness. The portion contacting the proximal surface is variable in position, lying either in or out of the undercut. The arm tapers gradually towards the terminal part which contacts the third surface and is resilient lying below the survey line throughout its whole length. Attachment to the denture may be by a strut, which is joined to the thicker extremity of the arm. Ring clasp – The ring clasp is very similar to the back action clasp. It completely encircles the tooth, its termination being in the near zone of the undercut surface. www.indiandentalacademy.com
  • 40. Medium survey line This class of survey line often indicates the use of an occlusally approaching arm, sometimes described as circumferential arm. Depending upon the bracing effect required this may be made of cobalt chromium, cast gold or wrought gold wire. A ginigvally approaching arm may be used on a tooth having a medium survey line. The various forms of bar clasps are appropriate, the length of the bar used depending upon the resilience required in the arm. If a larger degree of undercut is to be engaged, more resilience is required and the length of the bar is increased. www.indiandentalacademy.com
  • 41. Low survey line A tooth surface having a low survey line cannot bear a retentive clasp arm. In first place, in sufficient undercut exists to be effective in retaining the denture and second, a clasp arm placed in such an undercut will be situated dangerously near the gingival margin. Two dangers exists in bringing the arm too near the gingival margin. First if the arm is thick, a non self cleansing area is liable to exist immediately adjacent to the gingival edge. Second if there has been gingival recession or if gingivectomy has been done, it is necessary to keep the clasp arm well above the cemento enamel junction because cementum is liable to caries. www.indiandentalacademy.com
  • 42. Devan’s Clasp: The Devan’s clasp makes use of near proximal undercuts and has a small head which bears on the tooth entirely below the survey line. The Devan’s clasp should be reciprocated by a lingual or palatal strut, which contacts the tooth at the junction of its lingual or palatal and far proximal surfaces. The Devan’s clasp gives little bracing effect and some other means such as a deep square rest seat preparation must be used. www.indiandentalacademy.com
  • 43. Extended clasp arm: The extended clasp arm is similar to cast circumferential arm but it covers two teeth. It remains above the survey line of the first tooth, which in this case is low, and crosses into the undercut of the adjacent tooth. This type of clasp has a splinting action and distributes the lateral load over two teeth. Crowning the tooth: When the abutment teeth are all conically shaped, it may be necessary to crown them, at the same time developing desirable undercut surfaces. www.indiandentalacademy.com
  • 44. Diagonal survey line If an occlusally approaching arm is preferred, there are two possible clasp that can be used. In the first the rigid part of the clasp arm crosses from the near zone to the far zone above the survey line and sweeps round to return in to the undercut of the near zone. One disadvantage of this clasp is that it has no application when there is short clinical crown as insufficient space exists to accommodate the clasp arm. Since the diagonal survey line is often found on the buccal or labial surfaces of teeth that are shown in smiling, the conspicuous double arm may constitute a serious disadvantage. www.indiandentalacademy.com
  • 45. The second approach into the undercut is by a clasp arm that encircles the tooth on three surfaces. It first transfers the opposite surface of the tooth and then runs in the embrasure and finally crosses the surface from far to the near zone. When the survey line is a combination of diagonal and high, the ring clasp is always preferred to circumferential clasp arm. When a gingival approaches is preferred, L or T bar clasps are useful usually having the esthetic advantage over the occlusally approaching types. www.indiandentalacademy.com
  • 46. What is parallel blocking, shaped blocking, arbitrary blocking and relief? After the establishment of the path of placement and the location of the undercut areas on the master cast, any undercut areas that will be crossed by rigid parts of the denture (which is every part of the denture framework but the retentive clasp terminals) must be eliminated by block out. In the broader sense the term blockout includes not only the areas crossed by the denture framework during seating and removal, but also those areas not involved that are blocked out for convenience. Ledges on which clasp patterns are to be placed. Relief beneath connectors to avoid tissue impingement, and Relief to provide for later attachment of the denture base to the framework.www.indiandentalacademy.com
  • 47. Ledges or shelves (shaped block out) for locating the clasp patterns may or may not be used. However, this should not be confused with the actual blocking out of undercut area that would offer interference to the placement of the denture framework. Only the latter is made on the surveyor, with the surveyor blade or the diagnostic stylus being used as a paralleling device. Block out material may be purchased, or it may be made according to the following formula: Melt and mix together: 4 ½ sheets of base plate wax 4 ½ sticks of temporary gutta-percha stopping 3 sticks of sticky wax ½ tsp Kaolin Add ½ tube lipstick for color.www.indiandentalacademy.com
  • 48. PARALLEL BLOCK OUT, SHAPED BLOCK OUT, ARBITARY BLOCK OUT AND RELIEF The differences between paralleled block out, shaped block out, arbitrary block out, and relief are given below in a tabular form. The same factors apply to both the maxillary and mandibular arches, except that relief is ordinarily not used beneath palatal major connectors, as it is with mandibular lingual bar connectors, except when maxillary tori cannot be circumvented or when resistive median palatal raphes are encountered. www.indiandentalacademy.com
  • 49. SITE MATERIAL THICKNESS Proximal tooth surfaces to be used as guiding planes Hard base plate wax or block out material Only undercut remaining gingival to contact of surveyor blade with tooth surface Beneath all minor connectors Hard base plate wax or block out material Only undercut remaining gingival to contact of surveyor blade with tooth surface Tissue undercuts to be crossed by rigid connectors Hard base plate wax or block out material Only undercut remaining gingival to contact of surveyor blade with surface of cast Tissue undercuts to be crossed by origin of bar clasps Hard base plate wax or block out material Only undercut remaining gingival to contact of surveyor blade with surface of cast Deep interproximal surfaces to be covered by minor connectors or linguoplates Hard base plate wax or block out material Only undercut remaining gingival to contact of surveyor blade with surface of cast Beneath bar clasp arms to gingival crevice Hard base plate wax or block out material Only undercut area involved in attachment of clasp arm to minor connector PARALLEL BLOCK OUT www.indiandentalacademy.com
  • 50. SITE MATERIAL THICKNESS On buccal and lingual surfaces to locate plastic or wax patterns for clasp arms Hard base plate wax Ledges for location of reciprocal clasp arms to follow height of convexity so that they may be placed as cervical as possible without becoming retentive Ledges for location of retentive clasp arms to be placed as cervical as tooth contour permits; point of origin of clasp to be occlusal or incisal to height of convexity, crossing survey line at terminal fourth, and to include under cut area previously selected in keeping with flexibility of clasp type being used SHAPE BLOCK OUT www.indiandentalacademy.com
  • 51. SITE MATERIAL THICKNESS All gingival crevices Hard base plate wax Enough to just eliminate gingival crevice Gross tissue undercuts situated below areas involved in design of denture framework Hard base plate wax or oil-base clay Leveled arbitrary with wax spatula Tissue undercuts distal to cast framework Hard base plate wax or oil-base clay Smoothed arbitrary with wax spatula Labial and buccal tooth and tissue undercuts not involved in denture design Hard base plate wax or oil-base clay Filled and tapered with spatula to within upper third of crown ARBITRARY BLOCK OUT www.indiandentalacademy.com
  • 52. SITE MATERIAL THICKNESS Beneath lingual bar connectors or the bar portion of linguoplates when indicated Adhesive wax sealed to cast; should be wider than major connector to be placed on it 32-gauge wax if slope of lingual alveolar ridge is parallel to path of placement 32-gauge wax after parallel block out of undercuts if slope of lingual alveolar ridge is undercut to path of placement Areas in which major connectors will contact thin tissue, such as hard areas so frequently found on lingual of mandibular ridges and elevated median palatal raphes Hard base plate wax Thin layer flowed on with hot wax spatula; however, if maxillary torus must be covered, the thickness of the relief must represent the difference in the degree of displacement of the tissues covering the torus and the tissues covering the residual ridges Beneath framework extensions onto ridge areas for attachment of resin bases Adhesive wax, well adapted and sealed to cast beyond involved area 20-gauge wax RELIEF AREAS www.indiandentalacademy.com
  • 53. What is tripoding? How is the surveyor used for tripoding? After the final tilt of the cast has been selected, it must be recorded so that the cast may later be repositioned precisely. This procedure is referred to as tripoding. The simplest method consists of placing 3 cross marks on the tissue position of the cast, lingual to the remaining teeth at widely separated points while the cast and the vertical arm of the surveyor are held at fixed position. This will establish 3 points on the same horizontal plane. www.indiandentalacademy.com
  • 54. Method of vertical lines on the side of the cast. www.indiandentalacademy.com
  • 55. The cemented pin method. a). A hole about 10 mm in diameter and 10 mm deep is prepared in the lingual land area of the mandible cast with a large acrylic finishing bur. b). On the maxillary cast a hole is made in the area not included in the removal partial denture. c). The cast is oriented on the surveyor with the selected path of insertion. d). The pin is locked in the vertical spindle and lowered to the bottom of the hole. e). The vertical spindle with the pin is then locked in this position. f). Then the hole is filled with dental plaster. g). Once the plaster is set, vertical spindle is released from cemented pin.www.indiandentalacademy.com
  • 56. www.indiandentalacademy.com
  • 57. How do you survey the master cast? After the surveying of the diagnostic cast mouth preparation is done and the master cast is obtained. The master cast is placed on the surveyor table. The 3 points selected from the diagnostic cast must be identified with the analyzing rod held at the fixed vertical position; the cast is tilted in various ways until the tip of the analyzing rod contacts the points on the same horizontal plane. The tilt of the diagnostic cast and the master cast will be same now www.indiandentalacademy.com
  • 58. Measuring the degree of retentive undercut on the master cast. Undercuts may be measured with the use of • Undercut gauge such as in Ney and Jelenko surveyor. • By dial gauge such as incorporated in saddle lock retentoscope, ticonium, stress-o-graph. • Austenal microanalyzer. www.indiandentalacademy.com
  • 59. Ney gauges Ney gauges has three series of metal disc attached to the end of analyzing rod and vary in diameter that is 0.01”, 0.02”, and 0.03” and measured horizontally from the shank of the gauge to the rim of the gauge head. To measure an undercut, it is brought into contact with the height of contour and then rod is raised until the disc has made contact in the infra bulge area. The undercut may thus be shown to be from 0.01” to 0.03” depending on the size of the disc used. www.indiandentalacademy.com
  • 60. REVIEW OF LITERATURE Schmidt AH in 1953 stated that principles of surveying, significance of survey line, relation of clasp to the survey line and the opportunity presented by tilting the cast to control the location of undercuts are basic factors which enable the prosthodontist to solve any removable partial denture problem. Boitel RH in 1962 advocated Bachmann’s Parallelometer for prosthetic laboratories for its wide features such as 1.Surveying of diagnostic cast. 2.Seating precision instruments 3.Drilling pinholes into casting and porcelain facing 4.Waxing and carving precision attachments. www.indiandentalacademy.com
  • 61. RICHARD E COY in 1974 evaluated the importance of survey and design of diagnostic casts for removable partial dentures. The author summarizes the procedure of cast surveying and the features that are to be analyzed on a diagnostic cast. GOKHAN YILMAZ in 1975 presented the use of optical surveying of casts for removable partial dentures. Parallel light beams are produced by light bulbs with small dense filaments and condensed lenses contained in a box. The beams are made parallel with the vertical rod of the conventional surveyor by fixing the box firmly to an iron bar. Since the basic principles of the mechanical surveyor and this instrument are alike, the term optical surveyor has been selected. The border of the bright and dark zones indicates the survey line. www.indiandentalacademy.com
  • 62. Yilmaz G in 1976 presented optical surveying of cast of removable partial dentures and concluded that optical and conventional surveyors are based on the same principals. The cast is illuminated by parallel light beams, which are also parallel to the marker rod. The border of light and dark zones indicate the survey line. www.indiandentalacademy.com
  • 63. ARTHUR M LAVERE in 1977 in his article presented a simple procedure for survey and design of diagnostic casts. He concludes that survey and design should be done in a sequential manner as follows: • Locate a path by fitting the cast. • Mark the survey lines and tripod the cast. • Outline the rests and guide planes. • Draw minor connectors. • Draw major connectors. • Draw retention mesh for acrylic resin. • Draw acrylic resin base extension • Draw direct retainers. www.indiandentalacademy.com
  • 64. JOHN G KNAPP in 1979 et al narrated a technique for recording dental cast surveyor relations. Of the different techniques of tripodization the author emphasizes on using the cemented pin technique as an aid to the dental laboratory technician in relocating the predetermined survey position for master cast. ANTONY D STEAS in 1987 described a new method of recording and reproducing the tilt of a cast by means of a simple homemade instrument that attaches to a surveyor. This method allows the three selected points to be positioned on one movement, unlike other methods in which each of the three points are repositioned separately.www.indiandentalacademy.com
  • 65. CONCLUSION Surveying is the procedure of locating, delineating and appraising the contour and position of the teeth and associated structures before any removable or fixed partial denture is designed. Thus surveyor is a diagnostic tool which should be used by every practicing prosthodontist in order to establish a treatment plan that will be biomechanically sound while fulfilling functional and esthetic requirements. Dental cast surveyor, a mechanical instrument, is of great use for the prosthodontist in achieving the mechanical requirements of the removable partial denture which are biologically acceptable. It helps the prosthodontist in establishing the path of placement, removal and designing of the denture framework in such a way that it will allow the fabrication of biologic, biofunctional and bioesthetic prosthesis. www.indiandentalacademy.com
  • 66. So dental cast surveyor is an instrument every student and clinician should possess. Use of this instrument will not only make the job of technician simple, but also precise. Hours of time spent in the laboratory in guessing the interferences to the path of placement is also saved and the chair side time required to adjust those is also saved. www.indiandentalacademy.com
  • 67. REFERENCES 1. Textbook of clinical removable partial prosthodontics by Stewart, Rudd, Kuebker 2 edition. 2. Mc Cracken’s removable partial prosthodontics, ninth edition. 3. An introduction to removable denture prosthetics by Alan A Grant, Wesler Johnson. 4. Removable partial prosthodontics by Joseph E Grasso and Ernest L Miller 5. Partial denture by John Osborne / Atkinson (Pg 145- 147). 6. Essentials of RPD prosthesis by Applegate (Pg 103-107). 7. Knapp J.G Technique for recording the cast surveyor relations, J. Prosthet Dent 1979; 41:352-354. 8. Wagner A.G. A study of four methods of recording the path of insertion of removable partial dentures J. Prosthet Dent.1976; 35:267-272. 9. Yilmaz. G Optical surveying of casts for removable partial dentures J. Prosthet Dent.1975; 34:292-296. www.indiandentalacademy.com
  • 68. 10.R.H. Biotel- The parallelometer, a precision instrument for the prosthetic laboratory. J. Prosthet Dent.1962; 12:732. 11.Richard E Coy. Survey and design of diagnostic casts for removable partial dentures J. Prosthet Dent.1974; 32:103. 12.Sergio Reinaldo De Fiori. Transferring the path of insertion from the diagnostic cast to multiple master casts. J. Prosthet Dent.1983; 50:733. 13.Thanos M Kaloyannides. Reproduction of tilt of a cast on a surveyor. J. Prosthet Dent.1973; 30:465. 14.E.M. Katulski. Biologic concept of the use of the mechanical cast surveyor. J. Prosthet Dent.1959; 9:629-634. 15.Roberto Von Krammer. Accurately positioning a duplicate cast on the surveying table. J. Prosthet Dent.1989. 16.Michael F Mc carthy. An intra oral surveyor. J. Prosthet Dent.1989; 61:462-464. 17.Antony D Steas. Recording and reproducing the tilt of the cast on a surveyor. . J. Prosthet Dent.1987. 18.Arthur M La Vere. A simplified procedure for survey and design of diagnostic casts. J. Prosthet Dent.1977; 37:680. www.indiandentalacademy.com
  • 69. For more details please visit www.indiandentalacademy.com www.indiandentalacademy.com