Obturators / orthodontic seminars

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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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Obturators / orthodontic seminars

  1. 1. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  2. 2. • Anatomy • Types of prosthesis • Biomechanics • Classification of hemi maxillectomy defects and treatment planning. • Instructions to surgeons. www.indiandentalacademy.com
  3. 3. General principles. 1. Need for a rigid major connector. 2. Guide places and other components that facilitate stability ad bracing. 3. A design that maximizes support 4. Rests that place supporting forces along the long axis of the abutment tooth. 5. Direct retainers that are passive at rest and provide adequate resistance to dislodgement without overloading the abutment teeth. 6. Control of occlusal plane that opposes the defect,especially when it involves natural teeth. www.indiandentalacademy.com
  4. 4. Comparison of 3 retentive concepts(martin and king,1984) I. Retention by withdrawing the framework parallel to the path of insertion is greatest when both buccal and lingual clasps are used. II. Withdrawal of an obturator from the defect area greatly reduces the retention of buccaly placed clasps. www.indiandentalacademy.com
  5. 5. III. Withdrawal of an obturator from the defect area is resisted more effectively by lingual retention than buccal retention. IV. A lingual plate enhances retention in proportion to the number of teeth and length of the dental arch covered by the lingual plate. www.indiandentalacademy.com
  6. 6. Classification of Obturators • According to Origin of discrepancy : - congenital defect obturator - acquired defect obturator. • According to Location of defect: i. labial or buccal obturator ii. alveolar obturator iii. hard palate obturator iv. soft palate obturator v. pharyngeal obturatorwww.indiandentalacademy.com
  7. 7. • According to the Type of to the basic maxillary prosthesis attachment 1) Fixed obturator 2) Hinged or movable obturator 3) Detachable obturator. www.indiandentalacademy.com
  8. 8. • According to physiological movement of the surrounding tissue. a. Static obturator b.Functional obturator. Obturators covering defects in the area from the lips to the junction of the hard and soft palates are static Obturators. Those Obturators which provide closure in the soft palate and pharyngeal areas are functional Obturators.www.indiandentalacademy.com
  9. 9. Meatal obturator. • A meatal obturator is static. • It extends obliquely upward from the hard- soft palate junction to occlude against the turbinates and the superior aspect of the nasal cavity. • It may be preferable obturator when the cleft is wide,few undercuts exist,and the patient has an active gag reflex. www.indiandentalacademy.com
  10. 10. Surgical Obturators. Also called immediate temporary obturator. Dentulous patient • Patient is seen preoperatively. • Irreversible hydrocolloid impression is made of the maxillary arch. www.indiandentalacademy.com
  11. 11. • Functional limits of the palate are to be recorded in the impression. • Cast is poured and areas to resected marked on it. www.indiandentalacademy.com
  12. 12. • Teeth are removed from the cast in the areas of resection. • Wrought wire retainers are placed on the areas adjacent to the defect . www.indiandentalacademy.com
  13. 13. • Prosthesis is fabricated with cold cure or heat cure resin. • Anterior Teeth can be added if esthetic is desired. • clear Heat cure acrylic resin is desired as transparency will revel any pressure areas. www.indiandentalacademy.com
  14. 14. • If and when any adjustment is needed Build up of the defect side in modelling plastic is done and border mold the area. invest the obturator and replace the modeling plastic with auto polymerizing acrylic resin. • To reduce the weight the newly added obturator bulb is hallowed superiorly. www.indiandentalacademy.com
  15. 15. Edentulous patient • Fabricated in similar manner as in Dentulous patients. • Retention is obtained by using the ligature wire around the zygomatic arch and through the obturator. www.indiandentalacademy.com
  16. 16. Other methods of stabilizing the immediate obturator. • Piriform aperture wiring • Kirschner wires • Screw fixation • Sectional prosthesis. www.indiandentalacademy.com
  17. 17. • In large maxillectomy cavities ,composition impression compound is too heavy. • Radcliffe et al described an immediate obturator prosthesis of silicone elastomer foam,which was attached to an acrylic resin base. • This prosthesis is light and by engaging suitable undercut regions was retentive and avoided the use of accessory wires. www.indiandentalacademy.com
  18. 18. Treatment Obturators. • Also called temporary or transitional obturator. • Constructed about 7 days postoperatively, right after the packing is removed. • Used for about 3 months . www.indiandentalacademy.com
  19. 19. • If patient has an existing denture it is used in the construction of treatment obturator. – If denture is under extended ,an alginate impression is made with the denture in the mouth. – A cast is poured and cold cure added to the periphery of the old denture on the cast. • The old denture can also be readapted to the mouth using resilient denture lining material. www.indiandentalacademy.com
  20. 20. Construction of treatment obturator. • A stock impression tray which covers the desired area is selected. • The tray is built with utility wax in the area of the defect to support the impression material. • Wax is placed on the edges of the tray to protect the soft tissue. • Adhesive is applied on the impression surface of the tray . www.indiandentalacademy.com
  21. 21. • Load the tray with alginate. • Patient instructed to bend his head forward and also move from side to side so that functional limits of the soft palate can be recorded. • Impression is poured in artificial stone. • On stone cast a pencil line is drawn slightly inferior to where the oral mucosa and skin graft meet on the cheek. www.indiandentalacademy.com
  22. 22. •This area can be palpated on the patient as a fibrous band running horizontally on the cheek and at the height of where he buccal vestibule would have been. www.indiandentalacademy.com
  23. 23. • This band extend posteriorly and becomes part of the posterior portion of the defect. • Obturator should overlap the defect in this area. www.indiandentalacademy.com
  24. 24. • If teeth are present wrought wire retainers are build. • 2 thickness of baseplate wax is adapted over the whole cast. • No undercuts should be present along the walls of the defect side. www.indiandentalacademy.com
  25. 25. • Prosthesis is processed by Flasking ,dewaxing and packing with acrylic resin. • Prosthesis is deflasked ,trimmed and polished. • Prosthesis placed in patients mouth and checked for extent and compatibility of oral tissues. www.indiandentalacademy.com
  26. 26. • Fabrication of palatal contour. – Cavity on the palatal side of the obturator is filled with wax till proper palatal contour is established – Thin layer of separating media is placed over the wax and acrylic resin. – A plaster core is then poured over the wax and extended onto the acrylic resin to a point where reorientation of the core can be easily done www.indiandentalacademy.com
  27. 27. –Wax is removed from the defect side . –Separating medium is applied over the superior potion of the core. –Self cure acrylic resin is sprinkled to a thickness of 1 to 2 mm on the core. –Core is inverted and pressed into contact with the prosthesis and held till acrylic resin has set. www.indiandentalacademy.com
  28. 28. • Access resin is trimmed away and obturator is polished. • Alternatively whole defect side can be processed in acrylic and is then hollowed superiorly. www.indiandentalacademy.com
  29. 29. Permanent obturator for edentulous patients. • Given after 2 –3 moths after the operation. www.indiandentalacademy.com
  30. 30. Impression. • Position – Supine to be used for preliminary impression for patients with extensive surgical defects- provides more more visibility and access. – Erect position to be used for final impression so that dependent tissue do not become displaced from normal. • All other positions usually induce gagging and so should be avoided. www.indiandentalacademy.com
  31. 31. • Place an airway in the nostrils and pack the throat with gauze. • Extreme undercuts blocked with petrolatum impregnated gauze. • Lubricate the lips with petrolatum to prevent impression material from sticking to it. www.indiandentalacademy.com
  32. 32. Primary impression Build the stock tray with wax in the defect area to direct the impression material into the defect. • Make an alginate impression and pour the cast. • Fabricate individual acrylic resin impression tray. www.indiandentalacademy.com
  33. 33. Final impression • Impression material – rubber base – Irreversible alginates – Reversible alginates – Zinc oxide eugenol. • Place holes in the tray to retain impression material.or use adhesive in case of rubber base. • Impression tray tried in mouth to ensure that 2 mm space exist between the tray and the tissue. www.indiandentalacademy.com
  34. 34. • Tray loaded and inserted and patient told to purse his lips and swallow. • Some material can be directly put into the defect to insure that material reaches inaccessible areas. • Impression is boxed and stone is poured. • Any undesirable soft and hard tissue undercuts are blocked out,but these will be salvaged later to help increase the retention. www.indiandentalacademy.com
  35. 35. • Acrylic resin bases are made Occlusal rims are adapted and correct vertical dimension and centric relation is established • Tracing devices are not used due to lack of resistant base after surgery. • Teeth selection is done and baseplates are related to the articulator with a face bow transfer. www.indiandentalacademy.com
  36. 36. • The upper posterior teeth are occluded and balanced with the lower cast of the natural teeth. • Wax trial done in patients mouth to check esthetic and functional relationship. www.indiandentalacademy.com
  37. 37. Processing. • Denture base invested in the lower flask. • Palatal defect filled with modeling clay and given a palatal shape. • An acrylic bur is used to create a ledge around the periphery of the defect and to reduce the thickness of the bulb to about 2mm www.indiandentalacademy.com
  38. 38. • Tinfoil is adapted over modelling clay and extended beyond the periphery of the palatal defect by 1 cm. • Denture is packed processed , deflasked ,trimmed and polished. www.indiandentalacademy.com
  39. 39. • Portion of palate covering the modelling clay is removed readily as separating medium was applied in this area. • Modelling clay is removed and palatal section is cemented over the defect area with auto polymerizing resin. www.indiandentalacademy.com
  40. 40. • The denture with the hollow bulb is trimmed and polished and inserted in the patients mouth. www.indiandentalacademy.com
  41. 41. Alternative method. • Non defect side – Preliminary impression made of non defect side in alginate. – Stone cast is made and and acrylic resin custom tray is fabricated on it. – Tray is border molded in mouth and rubber base impression made of intact maxilla. – An acrylic resin base is then processed on the cast. www.indiandentalacademy.com
  42. 42. • Defect side. – Modelling plastic is adapted to he acrylic resin base on the defective side. – Distal buccal surface is molded by making the patient open and close his mouth .when maxillary resection is extended into the pterygoid region,this area will be influenced by the ramus of the mandible.when properly molded ,there will be an index of the anterior portion of the ramus evident in the posterior portion of the bulb. www.indiandentalacademy.com
  43. 43. • Patient is told to wear the obturator until the next day to determine any overextension and uncomfortable areas. • Patient instructed to eat only cold food as heat will have softening effect on the modelling plastic. • Sore areas are relived and additional relief of 1 to 2 mm given over the entire surface area of the bulb. www.indiandentalacademy.com
  44. 44. • Korecta wax painted over the relived modelling plastic . • The wax is applied over a number of time till a glossy appearance is obtained. • Prosthesis is left in mouth for 2-3 hours to get good final adaptation. • Impression poured in dental stone. • Cast is invested in lower portion of flask. • The bulb portion is waxed in proper thickness and contour. • Defect area processed in acrylic resin ,deflasked and polished. www.indiandentalacademy.com
  45. 45. Other Impression methods • Schmaman and carr(1992) • A foam impression technique for maxillary defects • This technique overcomes the problems of withdrawal of maxillectomy defect impression with or without limited space as he result of trismus. • Silastic foam material is used to make an impression which expands inside the defect and is extremely elastic to escape any deformation on removal. www.indiandentalacademy.com
  46. 46. • Luebke – Use of sectional tray in patients with trismus. • Beumer et al. – In this method the impression is refined with modeling plastic,a soft flowing wax,and an elastic impression material to record the defect. • Carl – Use of adhesive and undercuts that add additional alginate to a set impression when necessary. www.indiandentalacademy.com
  47. 47. Use of sectional impression was pioneered by Adisman It can be used where full depth of undercut must be recorded and a special tray loaded with impression material cannot be inserted. www.indiandentalacademy.com
  48. 48. • In this technique ,different sections of silicone putty are removed from mouth and reassembled. • Accurate impression of full depth of the defect has been obtained. www.indiandentalacademy.com
  49. 49. Permanent obturator for Dentulous patient. • Wire clasp embedded in the acrylic resin base are usually used when the prognosis of the remaining teeth is questionable. • Obturator bulb on cast frame is used for partially edentulous patients who have a significant number of sound teeth remaining. www.indiandentalacademy.com
  50. 50. Cast frame is preferred as it is – Less bulky – Less likely to distort – Stabilizes remaining teeth effectively. www.indiandentalacademy.com
  51. 51. • The frame and retentive portion of the frame is made and the obturator portion is made utilizing the cast frame as a base. • Wax (kerr utility wax) is adapted over the defect area of the frame. • Wax is softened and placed in moth . www.indiandentalacademy.com
  52. 52. • Patient asked bend his head from side to side and to swallow. • Glossy areas indicate tissue contact.and the whole procedure is repeated till wax fills the whole defect area. • Wax is then relived by 2 mm and adhesive is applied over it. • Heavy bodied rubber base material is applied over the wax. www.indiandentalacademy.com
  53. 53. • Patient told to do functional movements • Frame and obturator are removed and invested in stone . • Clear acrylic resin is processed to the cast frame. • Prosthesis is trimmed polished and painted with pressure indicating paste. www.indiandentalacademy.com
  54. 54. • Patient asked to do functional movements and then to swallow water. areas of pressure identified and relived. • Procedure repeated till no pressure areas are evident. • 1 mm of acrylic resin is trimmed off the obturator. • Oral thermoplastic wax is added to the tissue contacting surface(adaptol or iowa wax) www.indiandentalacademy.com
  55. 55. • Patient told to do functional movements and pressure areas relived and repainted with wax. • Patient told to sit with the impression in mouth for 2 hours to get the functional impression. • Impression chilled in cold water and processed. www.indiandentalacademy.com
  56. 56. • The prosthesis is polished and painted with pressure indicting paste to detect processing discrepancy. • Functional positional records are made and occlusion is refined. www.indiandentalacademy.com
  57. 57. Procedure for one piece hollow obturator. • Advantages i. There are no lines of demarcation on the denture to discolor ii. The undercut areas of the defect are thick enough to allow for adjustment if necessary. iii. It is simple and consumes very little more laboratory time than a conventional denture. iv. Accuracy is assured www.indiandentalacademy.com
  58. 58. • The denture is waxed as any conventional denture www.indiandentalacademy.com
  59. 59. • The denture is flasked and boiled out in usual manner. • The undercuts areas in defect are blocked out www.indiandentalacademy.com
  60. 60. • Entire defect area is relived with one thickness of baseplate wax. • Three stops deep enough to reach the underlying stone of the master cast are placed in the wax to facilitate proper positioning of the shim. www.indiandentalacademy.com
  61. 61. • One thickness of base plate wax is also placed in the top half of the flask over the teeth and palate area to form the top wall of the shim. www.indiandentalacademy.com
  62. 62. • Auto polymerizing acrylic resin is mixed and rolled to about 2mm in thickness after reaching the dough like stage. • A layer of resin is contoured over the wax relief in the defect site,with another layer over the wax in the top half of the flask. www.indiandentalacademy.com
  63. 63. • Flask is then closed and allowed to set for a minimum of 15 minutes. www.indiandentalacademy.com
  64. 64. • After curing the flask is opened and the wax is flushed off the shim with a stream of boiling water. www.indiandentalacademy.com
  65. 65. • Excess of acrylic is removed from the shim and placed back into the defect,using the three stops for correct positioning for final processing with heat cure resin. www.indiandentalacademy.com
  66. 66. • A layer of material is presses to place in the bottom of the defect,and the shim is reinserted for final processing. www.indiandentalacademy.com
  67. 67. Factors to consider for superior height of bulb. 1. If patients speech cannot be understood the bulb should be extended upward. 2. With maxillary resection much of the bone support for the cheek is removed.the obturator bulb height will reestablish this contour. 3. According to brown (1968) height of the bulb relates to the retention of the completed obturator. 4. Amount of Mouth opening of the patient www.indiandentalacademy.com
  68. 68. General considerations for bulb. • Bulb is not necessary with central palatal defect of small to average size where healthy ridge exists. • Not necessary in the surgical or immediate temporary prosthesis. • It should be hollow to aid speech resonance and to lighten the weight on the unsupported side. • It should not be so high as to cause the eye to move during mastication. www.indiandentalacademy.com
  69. 69. • It should be one piece,if possible,to provide better color matching and maximal patient acceptance. • It should always be closed superiorly • It should not be so large as to interfere with insertion if the mouth opening is restricted. www.indiandentalacademy.com
  70. 70. Instruction to patient . • To remove the prosthesis several times a day to wash the prosthesis and rinse the mouth. • Prosthesis to be cleaned thoroughly every evening. • Patient advised not to wear prosthesis while sleeping. www.indiandentalacademy.com
  71. 71. Thank you For more details please visit www.indiandentalacademy.com www.indiandentalacademy.com

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