Interproximal Enamel Reduction (stripping)

Interproximal Enamel Reduction (stripping)

1. I nterproximal enamel reduction (stripping) Supervised by : Prof. Dr. Maher A. Fouda prepared by: Dr. Abdullah H. Bayazed

2. Introduction: Inter-proximal reduction is the removal of a small amount of enamel from between the teeth to reduce their width. Inter-proximal reduction (also known as slenderizing, stripping, enamel reduction, reproximation and selective reduction)

3. Aim of reduction : The aim of this reduction is to create space for ideal tooth alignment during orthodontic treatment and to give teeth a suitable shape whenever problems of shape or size require attention. Prior to interproximal reduction, teeth slightly overlap During interproximal reduction Following interproximal reduction, the patient has a more aesthetically-pleasing smile and an improved bite.

4. Indication 1- Crowding/relapse of crowding: Sheridan , points out, orthodontists can use stripping to correct crowding of 4 to 8 mm. Severe crowding not indicated for IPR Mild crowding indicated for IPR

5. Van Der Linden suggests that dentists can prevent crowding, or improve conditions for the alignment of anterior teeth by taking advantage of the leeway space in selective stripping of some temporary teeth. But, primarily, orthodontists use stripping on permanent teeth . A- The crown of the temporary canine is stripped mesially in order to create space foralignment of the anterior teeth;

6. b- The crown of the first temporary molar is stripped mesially to create conditions that will facilitate eruption of permanent canine into its correct position. C- The mesial surface of the crown of the second temporary molar is stripped to ease eruption of the first bicuspid. d- The width of the second temporary molar is more or less equal to the width of the second bicuspid.

7. 2- inter-arch size discrepancies : Kesling in 1945 stresses the importance of a favorable inter arch tooth Size relationship for establishment of stable occlusion.

8. 3- Tooth shape and dental esthetics: Stripping can be used for the reshaping of enamel on some teeth, thus contributing to an improved finishing of orthodontic treatment and dental esthetics. canines were positioned to replace the congenitally missing maxillary lateral incisors. Cosmetic reshaping of the maxillary canines and esthetic bonding were completed.

9. 4- Macrodontia size discrepancies : in cases where teeth are crowded and larger than normal , proximal stripping can be considered.

10. 5- Crowding of mandibular incisors: stripping was first used to obtain space for the correction and prevention of crowding.

11. 6- To be performed on temporary tooth to improve occlusion. : Interproximal stripping is about to be performed on this temporary tooth to improve occlusion.

12. 7-Normalization of gingival contour and elemination of triangular spaces above the papilla (dark triangular) thus greatly improving esthetics and smile .

13. 8- Camouflage of Class II and III malocclusion: the use of mandibular stripping can be beneficial in camouflaging slight to moderate Class III conditions and overjet . In orthodontic treatment to camouflage Class II with extraction of two maxillary premolars, correcting the crowding and inclination of the mandibular incisors with stripping is an ideal solution. tendency Class III molar relationship. See case report 5 Class II molar relationship . (See case report 9)

14. 9- correction of the Curve of Spee : for the correction of an exaggerated Curve of Spee , it is necessary to create a few millimeters of space in the arch . This Can be achieved through stripping.

15. 10. Multiple Tooth Rotations In patients with multiple rotations, slenderization can provide wider interproximal contact facets that make relapse less likely ,Many orthodontists purposely flatten out contacts in the lower anterior regions in the belief that relapse can be prevented or at least minimized due to the proximation of the flat contacts.  

16. Contraindication 1- Sever crowding ( more than 8 mm per arch ): 2- Poor oral hygiene and /or poor periodontal environment : 3- Small teeth and hypersensitivity to cold : 4- Susceptibility to decay or multiple restorations: 5- severely rotated teeth for which access to the proper contact area is not accessible (in cases like this, it is recommended to either make room using the separation technique or wait until crowding in the area of the tooth is resolved and space is created).

17. 6. Shape of teeth : stripping should not be carried out on square teeth( rectangular-shaped teeth ), that is teeth With straight proximal surfaces and wide bases, as the shapes produce broad contact surfaces, and could potentially cause food impaction and reduced inter- septal bone. rectangular-shaped teeth

18. Tooth shape and enamel thickness According to Bennett and McLaughlin , three main dental shapes: rectangular , triangular , and barrel shaped teeth. Studies reveal that there is no relationship between dental shape and enamel thickness. Rectangular Triangular Barrel

19. Rectangular-shaped teeth do not show any “black triangles”, and slenderization is usually not favorable as too much tooth reduction is required to gain sufficient space in the dental arch. Triangular and barrel-shaped teeth often require slenderizing or cosmetic restoration to improve the aesthetics after orthodontic treatment. Barrel-shaped teeth and visible incisal spaces Triangular-shaped teeth and Black gingival triangle Rectangular-shaped teeth

20. Treatment planning A complete set of radiographs and model are nedded . From the x-ray, the clinician can determine: The convexity of each proximal surface. The thickness of enamel on each tooth. The size of fillings. The disposition of the roots.

21. The thickness of inter-proximal enamel can be estimated by projecting a line from the cervical line vertically to the occlusal or incisal plane. Dentin is projected in a straight line from cervical line or a line that tapers slightelly towards the pulp. Proximal enamel extension limited by lines parallel to the tooth’s long axis ( mesial : L1-L2 and distal: L3-L4).

22. If the tooth is rotated, the contour will not be shown accurately on the x-ray, and the model must also be used.

23. Initial model Progress model. IPR was required mesial and distal to the upper second bicuspid to achieve a better Class I relationship. Not enough stripping was done leading to dental intrusion of the bicuspid. lab set-up to determine where IPR might be required.

24. Re-creating the dimensions of the lab set-up Intra-orally prior to taking impression. The amount to be removed is highlighted in red, and the width dimension exported and sent as a reproximation form to the doctor. Needle-tipped diamond bur with copious irrigation to effeciently re-contour inter-proximal surfaces.

25. Diamond disk with disk guard to protect the soft tissue. Mouth mirror to protect the tongue. Disk is spinning labially towards the mirror at very low RPMs. Smooth parallel lines without sub-gingival ledges is the goal.

26. Perforated diamond strips in three thicknesses ( Yellow =extra fine, Red =fine, Blue =medium). Extra tight contacts can be effectively opened by first starting with the yellow and working up to the blue. Thickness gauge to verify the amount removed in 1/10th mm increments. Using diamond strips to round out line angles and create natural-looking dental anatomy.

27. The orthodontist must decide how much enamel can be removed from each tooth surface, allowing for a minimum convexity to form the contact point, a sufficente amount of enamel and avoidance of root contact.

28. How much enamel can be reduced? There are no studies indicate how much of enamel is needed for adequate protection of tooth against carious , thermal or chemical damage . The variation in the thickness of enamel suggests that there is no protective advantage in preserving thick enamel inter-proximally, when comparative thin enamel occurs naturally on labial, buccal and lingual surface.

29. Jhon Sheridan suggests that if 50% of inter-proximal enamel was removed , 6.4mm of space could be generated from 8 buccal posterior contacts (0.8mm/contact) and 2.5mm of space could be created from 5 anterior contacts (0.5mm/contact) so the total space gained 8.9mm within the arch.

30. Steiner states that for each millimeter of protrusion , the discrepancy is reduced by 2 mm . Torque enlargement without protrusion permits a gain of 1 mm per 5° of radicular palatal torque enlargement.

31. Clinical procedure Clinical procedure involving enamel reduction, anatomic re- countouring and protection of proximal enamel surface of permanent teeth .

32. Steps Involved In Inter-proximal Reduction 1- Separation: this involves separating the teeth to be reduced by the use of separators to make the area of reduction more accessible.

33. 2- Reduction: the enamel is reduced with the help of appropriate abrasive strip, diamond cutting discs or burs.

34. 3- Re-contouring: after the reduction the teeth are carefully reshaped to re-create the original contours.

35. 4- Polishing: The tooth surface is polished to reduce the surface enamel roughness. Enamel surface after reduction Same surface after polishing With Sof Lex Discs

36. 5- Protection: The teeth that reduced are fluoridated as the outer protective fluoridated enamel layer is lost. Application is very easy! A small amount of air may be used to dry the tooth surface. A little brush is used to apply the tooth colored varnish to the teeth and at the gumline . The varnish begins to set on contact with the teeth. It is safe for all ages. Fluoride varnish will last at least 4 hours after application. Patients are instructed to not brush for a certain amount of time after application and avoid hot and/or sticky foods.

37. Techniques for enamel reduction There are various methods recommended by various authors for IER. Some of them : Hudson used lightning steel strips of 0.10- 0.12 mm. he followed it by finshing abrasive strips to remove the roughness.

38. Paskow , begins stripping with wide metal abrasive polishing strips to gain proximal access followed by coars abrasive metal disc and then single-sided diamond disc . He used a small diamond stone bur to round off the sharp edges and finally rubber abrasive disc to polish all surfaces.

39. Peck and peck recommended use of double sided abrasive steel strip for gross reduction when less than 0.2 mm per surface of enamel has to be reduced and a safe sided steel abrasive disc on slow speed straight handpiece for reduction beyond 0.2 mm per surface. Finshing is done with cutterfish strips.

40. Zachrisson used a thin flexible diamond disc for gross reduction, steel strip for contouring, finshing and polishing surface for surface smoothness.

41. John Sheridan advocated air-rotor striping by use of 699L small tapered crosscut fissure carbide bur with an extended cutting area. Finshing is done by polishing with carbide finshing burss,,finshing diamond, polshing disc of hand held finshing strips. Occlusal Approach customized carbide bur Lateral Approach

42. Protection of soft tissues Sheriden advised use of 0.20 inch brass wire to be placed gingivally between teeth to be reduced. This wire also serves as an indicator for reduction of enamel. Rubber dam can be used to isolate the working area and protect the rest of the tissues. GPS Separator Disc guard wedge Rubber dam Cheek & lip retractor

43. The ABC ’s of IPR with a straight nose cone hand-piece & diamond disc A void the tongue, lips, & cheeks B race yourself with a finger rest C heck for fully-broken contact

44. A: Avoid the tongue, lips, & cheeks: Protect the patient’s soft tissues with a mirror & cheek retractor .

45. B: Brace yourself with a finger rest : Use a finger/thumb rest to stabilize the hand-piece & align the disc

46. B: Brace yourself with a finger rest: Line up the handpiece with the contact area

47. C: Check for fully-broken contact Use the hand-piece to blanch the gums

48. Precautions Always carry out IER with new instruments. Carefully protect soft tissues. Proximal stripping should not be carried out until dental rotation has been corrected, so that it can be done at the correct contact area . Stripping should be carried out sequentially. Stripped areas should be paralleled. The stripped areas carefully polished. The stripped areas should be flouridated following polishing. Avoid placing contact areas sub- gingivally .

49. instruments

50. There are 3 methods to reduce teeth inter-proximally: 1-Abrasive Strips Hand held & Motor driven. available in either single - or double sided coatings. Come in three grades of coarseness ( fine , medium , and coarse ). Use for anterior teeth . Use for minor tooth reduction. Useful for re-contouring teeth. Less aggressive removal of enamel . Thickness : 0.010 mm & 0.012 mm

51. Flex-View TM Interproximal Strips perforated stainless steel strips allow optimal visibility and minimise clogging. They also for easy access for interproximal stripping and finishing. All strips are single-sided and autoclavable

52. Interproximal Serrated Strips: Use these interproximal serrated strips for ease in opening up bonded proximal contacts prior to reduction with diamond strips.

53. Diamond Interproximal Strips - Autoclavable Reduce interproximal enamel. These very thin strips (0.08mm / 0.003”) are made of electrolytically bonded diamonds on a vibro cushion base.

54. Tooth Stripper Kit : The hand-held Tooth Stripper provides a more precisely controlled method of reducing enamel at interproximals , unlike powered instruments which often remove more enamel than desired.

55. 2- Abrasive Discs Usually for anterior teeth Removes more enamel than abrasive strips. Risk of cutting lip and gingiva . Must finish with abrasive strips . Risk excessive enamel reduction . Use a disc guard to protect the patient .

56. Diamond Discs Use Diamond discs for both separating and contouring. Available single and double-sided. Designed for use with a straight handpiece only.

57. Flexible Serrated Diamond Discs Used for anterior inter-proximal stripping. Available in two sizes and are double sided. For use with a straight hand-piece only, and can be used with disc guards.

58. Disc Guard, Adapter and E-Type Hand-piece For use with a straight hand-piece, Disc Guards have visual access windows for safety, and are available in two sizes. The Adapter allows discs to attach to a straight hand-piece.

59. Flex- View TM Snap-On Finishing Discs For interproximal stripping . Also used for contouring and shaping of embrasure areas. note: when using a friction grip mandrel, a slow speed hand-piece (not to exceed 30,000rpms) must be used. Thickness of disc 0.10mm.

60. Flex- View TM Curved Disc Used in anterior inter-proximal stripping. Straight handpiece only. Thickness of disc 0.10mm.

61. Flexible Solid Honeycomb Designed for intermediate contouring and inter-proximal stripping.

62. Flex- View TM Mesh Discs For interproximal stripping and ultra-fine contouring/shaping Straight handpiece only

63. Incisal Contouring For shaping and contouring

64. Plaster Disc Great for sectioning teeth from plaster model for diagnostic wax ups. Replaces the use of a coping saw. Not recommended for intra-oral use.

65. 3-Air Rotor Stripping. • Tungsten carbide or diamond burs. • High speed hand-piece.

66. Safe-Tipped Air-Rotor Stripping (STARSTM) Burs : The STARS series of burs has been developed to assure the precision reduction of interproximal enamel while drastically reducing the possibility of excessive bur-induced grooves.

67. Kit includes: A sterilisable 10 piece bur block , four safe-tipped cross-cut carbide fissure burs (O/No 9001-699ST) Two medium-particle size (100 microns) Safe-tipped finishing diamond burs (O/No 9001-5MDST) Two fine-particle size (30 microns) Safe-tipped finishing diamond burs (O/No 9001-5FDST) Two anterior fine needle diamond burs Non safe tipped. For anterior interproximal stripping. Open field not necessary. Head size 1.6mm, length 5mm (O/No 9001-55000).

68. Incremental Thickness Gauge Six stainless steel gauges for measuring inter-proximal spaces. A set consists of the following thicknesses: 0.25mm, 0.5mm, 0.1mm , 0.2mm, 0.3mm , and 0.4mm .

69. The Sheridan Interdental Space Measuring Gauge: The gauge consists of a series of cylinders, of progressively increasing diameters, which can measure natural or created interdental space from 0.75 to 3.0mm in increments of . 25mm.

70. Manual Instruments: Enamel hand stripper: Contouring kit . Mini stripper . Cello Stripper . Hand-piece Driven Instruments : C-SAW Inter-proximal Reduction System. Targeted ASR. Inter-proximal reduction instruments

71. Manual Instruments: Enamel hand stripper: KIT INCLUDES: • 1 Stainless Steel Enamel Hand Stripper • Abrasive Strips Sample Pack ADDITIONAL STRIPS AVAILABLE: Single sided strips- package of 10 pcs . Double sided strips- package of 10 pcs . STRIPS AVAILABLE IN: Fine, Medium and Coarse WIDTHS AVAILABLE: 4mm, 6mm, 8mm

72. CONTOURING KIT Removes interproximal tooth mass to produce additional intra-arch space. May also be used for opening contact points, re-contouring or removing overhanging fillings.

73. MINI STRIPPER: • Small and easy to handle. • Complete with 16 refill strips (single side only). ADDITIONAL STRIPS AVAILABLE: Serrated strips- package of 10 pcs . Steel strips- package of 10 pcs . Diamond strips- package of 10 pcs .

74. Cello Stripper The Cello Stripper Holder accepts 2 sizes of steel abrasive strips- 2mm and 3mm. KIT CONTAINS: •Stainless Steel Strip Holder •Sample Package of 10 Abrasive Strips (2mm or 3mm width, single-sided or double-sided)

75. Manual Microcut Manual handling saw blade strip for removing excesses of any type of filling materials from the interproximal areas without breaking the contact point relation due its thickness of only 0,05mm;

76. Manual stripping, the equipment used (ETM Corporation, Glendora, California, USA).

77. MASTERING INTERPROXIMAL STRIPPING : WITH INNOVATION IN SLENDERIZATION

78. Hand-piece Driven Instruments C-SAW Inter-proximal Reduction System: Advantages: • Single-sided files provide greater control • 2 different file types & 4 different file grades provide more precise reduction and finishing • GPS Clamp opens contact area for ease of file entrance and prevents injury to soft tissue .

79. Features • A low-speed, high torque reciprocating hand-piece for controlled reduction • Slenderizing reciprocal files: _ Stainless steel with a diamond coating _ Color coded for easy identification • System is totally autoclavable .

80. Targeted ASR

81. Defined Reduction Defined follow-up contouring. Final Polishing

82. Instruments used for interdental enamel reduction of posterior teeth (modified Tuverson technique) A , extrafine diamond disk in contra-angle hand piece and Elliott separator; B,C : interproximal corners were rounded with cone-shaped triangular diamond bur.

83. Remin+ TM Gel For enamel remineralisation after tooth whitening, interproximal stripping, occlusal equilibration and decalcification. Shown to be effective in enamel remineralisation process of decalcified teeth. Comes in a 120ml (4oz) squeeze bottle.

84. Case reports

85. Case 1. Woman (age, 31 years) with mild Class II malocclusion and mandibular crowding at the start of treatment;

86. Interproximal enamel reduction on all teeth mesial to the first molars.

87. 6 years after completion of orthodontic treatment with lingual retainer bonded to 6 anterior teeth. Note the inter-proximal caries lesions (grade 1) on the maxillary left first and second premolars (arrows). There is also a small caries lesion (grade 1) on the mesial aspect of the maxillary second premolar.

88. Case 2. Boy (age, 13 years) with Class I bimaxillary crowding at the start of treatment;

89. D and E , after stripping in the anterior and posterior regions (note the improved tooth morphology, particularly of all 4 first premolars);

90. F-H , 4 years after appliance removal, gingival conditions are normal with intact interdental and labial gingivae .

91. Case 3. A-C , Boy (age, 13 years) with Class I bimaxillary crowding at the start of treatment;

92. D and E , stripping of all teeth mesial to the first molars;

93. F-H , 5 years after treatment, with gold-coated .030-in lingual retainer bonded to both canines. Note the optimal tooth shapes and intact interdental and marginal gingival conditions. at the start of treatment

94. This 30-year-old woman had extremely large central incisors with overlapping maxillary and mandibular teeth. An occlusal view showing the overlapping central incisors. Cosmetic contouring was first performed on the maxillary central incisors and mandibular anterior. Case 4

95. After contouring the mandibular anterior teeth, they were polished with an impregnated aluminum oxide wheel (Cosmetic Contouring Kit, Shofu , Menlo Park, CA). Next, the maxillary laterals were bonded with composite resin and contoured and finished with ET carbide finishing burs ( Brasseler ). Better tooth proportion and straighter appearing teeth can be seen here before the final polishing.

96. Final result shows a straighter arc with more proportional teeth. Pretreatment view of the smile. Post-treatment view showing better harmony with the smile.

97. Case 5 A. Patient with minimal overbite and overjet , tendency toward Class III molar relationship , minimal upper crowding, and moderate lower crowding (continued on next page).

98. Appraising arch form after leveling, alignment, and space management. Because lower incisors need to be retracted distally and upper incisors placed over them to establish optimum overbite and overjet , anterior ARS is also indicated. Initial ARS sites in lower arch (arrows); separators placed to gain space for additional ARS.

99. Proper buccal inter- cuspation and acceptable incisal relationships after treatment. Lower crowding resolved without lateral or anterior expansion.

100. case 6. A , Patient with triangular crown morphology. Reducing black triangle by changing point contact (B) to a broader surface (C) by interproximal reduction. Orthodontic space closure and soft tissue filling the gingival embrasure. A

101. Reduction of black triangle with inter-proximal reduction. A , Point contact with black triangle present between central incisors. B , Inter-proximal reduction with medium diamond strip. C , Post-treatment. Complete fill of soft tissue in gingival embrasure by closing space and creating a broader contact that is closer to the alveolar crest. A B C

102. Case 7 Female patient (27 years of age ) with Class I bimaxillary crowding at start (a-c).

103. ( d,e ) After stripping in anterior and posterior regions of both the maxillary and mandibular tooth. (f) during orthodontic treatment.

104. At the end of therapy with six unit bonded lingual retainers in both dental arches (g- i )

105. Case 8 Female (31 year Old) patient with Class III malocclusion and mandibular incisor crowding.

106. marked anterior and posterior stripping was done after 1 month of leveling. final result

107. The radiograhs Show normal height and width of the interdental alveolar bone, with apparent lamina dura oulines around roots. long term result 12 years later

108. Case 9. A 13.11 years old female presented with a Class II Division I malocclusion. Facially, the patient appeared symmetrical, with normal lip competence, with a slightly cconcave profile and a retruded chin.

109. Pre treatment upper and lower intra-oral view.

110. Combi pull headgear. Initial arch wire . Application of an anterior bite plate

111. Application of Class II elastic on rectangular posted archwires .

112. Interproximal enamel reduction of lower incisors.

113. Finishing stage improving intercuspation

114. Post treatment facial photographs after 18 months of orthodontic treatment.

115. Post-treatment intraoral photographs

116. The powerful combination of reprox and nickel titanium gave us this result in less than three months treatment time. CASE 10

117. You can see how perfectly a diamond disk fits between the teeth. This is an ideal instrument for reprox . You simply disk through the contact point, making sure to go all the way down to the gingiva . Then polish with a finishing bur and a polishing strip. Here is the net result. You can see the amount of enamel removed is quite small, but it creates enough space to alleviate the crowding. More reprox can be preformed at subsequent appointments as needed.

118. This picture shows the incredible flexibility of nickel titanium arch wires. Even with severe rotations we were able to get complete bracket engagement by using nickel titanium 6 arch wires. The strength and flexibility of nickel titanium coupled with reprox allowed for this dramatic progress in less than three months.

119. an example of a case finished within 6 months leaving the teeth with uneven stripped edges.

120. THANK YOU HAVE A NICE DAY المكلاء م/ حضرموت/ اليمن