Management of impacted teeth /certified fixed orthodontic courses by Indian dental academy


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Management of impacted teeth /certified fixed orthodontic courses by Indian dental academy

  1. 1. Management of impacted teeth
  2. 2. INDIAN DENTAL ACADEMY Leader in continuing dental education
  3. 3.  An impacted tooth is a condition in which a tooth is embedded in the alveolus so that its eruption is prevented or the tooth is locked in position by bone or by adjacent teeth.
  4. 4.  Studies have reported that the incidence of tooth impaction varies from 5.6 to 18.8 % of the population.( Kramer RM, Williams AC and Dachi SF, Howell FV. Oral Surg Oral Med Oral Pathol 1970, 1961)  Any tooth in the dental arch can be impacted, but the teeth most frequently involved in a descending order are the mandibular and maxillary third molars, the maxillary canines, the mandibular and maxillary second premolars, and the maxillary central incisors.
  5. 5.  But, the maxillary canine, has been the most frequently impacted teeth.  In our esthetic-conscious society, it is increasingly important to preserve the natural dentition. This certainly includes keeping or “saving” the impacted teeth.  Replacing or “substituting” the teeth that may be lost because of impaction just is not an appealing treatment option.
  6. 6. Diagnosis:  The diagnosis and localization of the impacted teeth are usually made on the basis of clinical and radiographic examination.  The routine panoramic radiograph of the mixed dentition patient can also be used to identify the potential impaction of the teeth.  Computed tomography (CT) has recently been introduced as a standard method used in medical radiology to detect bone pathology.
  7. 7.  V. Ravinder, Nikhar Anand verma, and Valiathan: 3 - Dimensional Computed Tomography. A new method for localization for impaction of canine:  The proper localization of the impacted tooth plays a crucial role in determining the feasibility as well as the proper access for the surgical approach, the proper direction for the application of orthodontic forces, and the extent of root resorption, and damage to the adjacent teeth. ( Bishara SE, Semin Orthod 1998)
  8. 8.  To increase the diagnostic accuracy, conventional polytomography has been used. Computed tomography eliminates blurring problems of conventional tomography and increases the perceptibility of root resorption substantially.  CT has been proven to be most effective in detecting root resorption.  CT is also used for assessing the positions of the teeth and their mutual relationship compared to other diagnostic methods. (Elfteriadis JN, Athanasiou AE,Int J Adult Orthod Orthognathic Surg. 1996)
  9. 9.  Disadvantage of CT is the relatively high radiation dose to the patient and also cost. Preda et al (1997) reported on the technique of spiral CT with a 1:1 or 2:1 pitch using multiplanar reconstruction. Spiral CT reduces examination time and the risk of accidental movement, without loss of image quality. The probability of stochastic effects , expressed as an equivalent whole body radiation dose , in this CT approach increases about 2-8 times, compared to conventional full mouth or panoramic radiograph.
  10. 10.  A 21 year old female patient reported to the orthodontic department with a complaint of retained deciduous left upper canine. She presented with a class I molar relationship, a non-mobile retained deciduous canine and lower incisor crowding.  In order to carefully localize the impacted canine and predict the prognosis accurately, it was decided to carry out a spiral CT scan.
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  12. 12.  The use of lateral cephalometric radiographs forms an important diagnostic tool in orthodontic treatment as well as orthognathic surgery.  Three-dimensional imaging of the human body via computed tomography has been available to the field of medicine for the last 30 years  With the development of Cone Beam Computed Tomography, there has been a drastic reduction in radiation exposure to the patient, which allows its use for safely obtaining 3 dimensional images of the craniofacial structures. (Ashima Valiathan, Siddhartha Dhar, Nikhar Verma TIBAO (in Press) 2006 )
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  15. 15.  Treatment options:  There are four treatment options for impacted teeth Observation  Intervention,  Relocation,  Extraction. Preimpaction periods Postimpaction periods Surgical relocation Orthodontic relocation
  16. 16.  OBSERVATION – Observation of the dentition normally begins with the completion of the deciduous dentition eruption and ends with the removal or eruption of the impacted tooth. The preimpaction observation begins with the eruption of first permanent molars at approximately 6 years of age.
  17. 17.  INTERVENTION: If a decision to treat is made, treatment should be as minimal as needed to facilitate natural eruption. “The majority of impacted teeth erupt if hard – or soft – tissue obstructions are removed from their eruption paths.” Di Biase conducted a survey, which found that after the removal of supernumerary teeth, 75% of the impacted maxillary incisors spontaneously erupted. (Di Biase DD. Dent pract Dent rec1971)
  18. 18.  RELOCATION: When interceptive treatment fails to improve the position of the developing tooth or when teeth is impacted, efforts to reposition them should be considered Surgical relocation: Indication’s for surgical repositioning include: patient’s age, the need to eliminate or minimize orthodontic treatment and patient compliance. Other factors to consider are presence or absence of adequate space, shape and status of the impacted tooth, and shape and status of the adjacent teeth.
  19. 19.  Orthodontic relocation: Kokich and Mathews recommended surgical exposure and orthodontic eruption of an impacted tooth when its apex is completely formed. Frequently. Space must be orthodontically created before the clinician can surgically expose and orthodontically erupt an impacted tooth. ( Kokich VG, Mathews DP. Dent Clin North Am 1993)
  20. 20.  Complications associated with orthodontic repositioning of impacted teeth include – absence of or inadequate keratinized gingivae, reduced sulcular depth, gingival recession, increased gingivitis, ankylosis, multiple exposures, devitalization, pulpal obliteration, external root resoption, injury to adjacent periodontium, marginal bone loss and extraction of impacted teeth.  “Clinician should consider only those treatment goals for impacted teeth that minimize injury to the dentition and periodontium.”
  21. 21.  EXTRACTION: Since it is not possible to reposition all impacted teeth within the alveolus, their removal may be indicated. Complications that are associated with the surgical removal of the impacted teeth include periodontally compromised adjacent teeth, damage to adjacent teeth, root fracture, neuropathy, sinus involvement and osseous defect.
  22. 22. Impaction of canine
  23. 23.  An impacted maxillary canine is usually stationary and asymptomatic. In rare cases, emergence may start late in life, sometimes activated by the insertion of the denture, leading to pressure atrophy of the bone and mucosal covering of the impacted tooth. Other complications consists of follicular cysts and late resorption of the impacted canine.
  24. 24.  Incidence of canine impaction : ( Bishara AJODO: 1992) Dachi and Howel (1961) reported that the incidence of maxillary canine is 0.92% whereas Thilander and Myrberg (Scand J Res 1973) estimated the cumulative prevalence of canine impaction in 7-13 year old children to be 2.2%, and Ericson and Kurol (EJO 1986) estimated the incidence at 1.7%. Impactions are twice as common in females (1.17%) than in males (0.15%). The incidence of mandibular canine impaction is 0.35%. (Dachi and Howell 1961)
  25. 25.  Prediction of impaction: Palpation of the buccal alveolar bone is the most useful clinical method to predict the eruption of the canine. A negative finding on palpation is more difficult to assess because this may include both normal and abnormal situations.
  26. 26.  1. 2. 3. 4. 5. 6. Treatment planning: When an ectopic path of canine eruption or a definite impaction is diagnosed, several factors should be considered in the treatment planning. Age of the individual and dental maturation. Space conditions. Resorption of the permanent incisor roots. Position of the canine. Form of the crown. Patient demand for treatment.
  27. 27.  1. 2. 3. 4. 5. 6. Treatment option: No treatment of the unerupted canine Prophylactic space augmentation. Extraction of the primary canine. Surgical exposure and orthodontic repositioning. Surgical repositioning. Extraction of the impacted canine and movement of the first premolar in its position.
  28. 28.  Prevention of maxillary canine impaction : Selective extractions of the deciduous canines as early as 8-9 years of age has been suggested by Williams (AO 1981) as an interceptive approach to canine impaction in class I uncrowded cases. Ericson and Kurol (EJO 1988) suggested the removal of the deciduous canine before the age of 11 years will normalize the position of the ectopically erupting permanent canines in 91% of the cases if the canine crown is distal to the midline of the lateral incisor. On the other hand the success rate, if the canine is mesial to the midline of the lateral incisor is only 64%.
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  30. 30.  No treatment: In few cases, ectopically positioned canine may spontaneously upright and show a normal eruption. The most frequent complication appears to be the development of the follicular cyst. The treatment of choice for this condition is usually fenestration of the cyst. When the impacted canine and adjacent teeth are in close proximity, loss of attachment ensues around these teeth. The final result can be extensive marginal breakdown, which may not only require removal of the impacted canine but also effected neighboring teeth.
  31. 31.  A variant of this condition is the loss of bone from denture pressure, which may expose an otherwise fully impacted canine. This condition also necessitates removal of the canine.
  32. 32.  Prophylactic space augmentation : Elimination of severe crowding in the dental arch can make room for an impacted canine and possibly simulate eruption into the correct position.
  33. 33.  Extraction of the primary canine : In young individuals 10-13 years old, extraction of the primary canine can correct a palatally erupting ectopic maxillary canine. When the cusp of the canine had passed medial to the midline of the root of the lateral incisor, 645 of the ectopically positioned teeth could be corrected and 91% could be corrected when the canine was located more distally.
  34. 34.  In view of the generally favorable results, extraction of the primary canine is the treatment of choice in young individuals to correct palatally erupting maxillary canines provided that normal space is present and no incisor resorption is found.  Extraction of the primary canines may show less favorable results with ectopic permanent canines located in a more horizontal position high in the alveolar position.
  35. 35.  Exposure and orthodontic repositioning : This is usually the treatment of choice in cases of ectopic positioning, and normally leads to a predictable and successful result. However minor complications can be encountered, such as loss of pulpal sensitivity, root surface resorption, loss of marginal bone support, and gingival recession.
  36. 36.     The prognosis for orthodontic correction depends on, the patients age, space conditions, and the sagittal and transverse position of the canine crown root. In general, exposure alone can be expected to lead to eruption in 65-95% of the cases. The optimal time for treatment is during adolescence. The more vertical the orientation of the impacted canine, the better. An axial inclination which is greater than 45° distally may worsen the prognosis. The closer the crown is to the midline and the root to the midpalatal suture, the poorer the prognosis. Finally the PDL space should be visible along the entire root surface and the root apex should not be dilacerated.
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  38. 38.  Management of labially positioned canine : Labial position of the maxillary canine is less frequent than palatal impaction and is often caused by insufficient arch length. Fournier et al (AJO 1982) suggested that labially impacted teeth with a favorable vertical position may be treated initially by surgical exposure but without the application of the traction force. The absence of an adequate band of attached gingiva around the erupting canine may cause inflammation. Vanarsdall and Corn (AJO 1977) emphasized that it is hazardous to move teeth in the presence of inflammation.
  39. 39.  Before the labially impacted canine is exposed careful consideration should be given for creation of sufficient space to allow for the canine to be positioned in the arch.  During the surgical procedure, Vanarsdall and Corn recommended placement of surgical dressings to protect the tissue for 7 to 10 days. After removal of the dressing, a direct bond attachment can be placed in the dry field and tooth movement can then be initiated.
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  41. 41.  Treatment of impacted canines has been advocated for occlusal, functional, and esthetic reasons. Root resorption of the adjacent teeth, cyst formation, infections, periodontal defects, and referred pain have been reported.  Traditionally, most surgical techniques involved exposure of the entire crown.  An extensive surgical procedure was used for the placement of the lasso loop wire ligature around the neck of the tooth, which often required removal of bone beyond the CEJ. Which was reported to cause most serious damage.
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  43. 43.  Management of palatally impacted canine : Palatally impacted canines erupt without intervention, and this impeded eruption is due to the thickness of the palatal cortical bone, as well as the dense, thick and resistant palatal mucosa. Palatally impacted canines are often inclined in a horizontal / oblique direction. The general premise is that there should be adequate access to the crown of the canine, allow efficient control of bleeding during attachment of brackets. The design of the flap should ensure adequate blood supply.
  44. 44.  Surgical repositioning: Maxillary canine impaction is often not detected before root development is complete. However if transplantation is carried out early, the prognosis is very favorable. - Ectopic location where the canine’s path of eruption has resulted in marked resorption of the lateral and central incisor root. - -Ectopic placement of the canine, where surgical exposure and subsequent orthodontic realignment are difficult, impossible or can seriously damage the supporting structures of adjacent teeth.
  45. 45.  When surgical exposure and orthodontic repositioning have failed or were refused.  Canine transplantation should be planned as early as possible, preferably at 11 or 12 years of age when the root development is not yet complete.  Before transplantation is decided upon, it is essential that a detailed analysis of the space conditions of the recipient site be made.
  46. 46.  A common method for exposing impacted canines was to cement a orthodontic band at the time of exposure.  A “closed eruption” in which the crown is surgically exposed, an attachment is bonded during the exposure, and the flap sutured back over the crown, leaving a twisted soft ligature wire passing through the mucosa to apply the orthodontic traction.  In “open window” eruption technique, a flap is raised and a minimum amount of bone is removed, enough to expose the tip of the impacted crown to be bonded.
  47. 47.  When the tip of the canine is located outside the palatal bone presurgically, only 3-4mm of palatal mucosa is sectioned, and no bone has to be removed to gain access for bonding.  In the flap design frequently, a sulcular incision along the neck of the teeth is performed, and the mucoperiosteal flap raised included the gingival margins and the lingual aspects of the interdental papillae.  Other techniques involved autotransplantation of canine, and posterior segmental osteotomy, after the removal of the canine and advancement of the posterior segment to close the extraction space.
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  51. 51.  Adrain Becker, and Stella Chaushu : Success rate and duration of orthodontic treatment for adult patients with palatally impacted maxillary canines: (AJODO 2003) A sample of 19 adults (mean age, 28.8 + 8.6 years; range, 20-47 years), who had been treated for a total of 23 impacted maxillary canines, was compared with a young control group (mean age, 13.7+ 1.3years; range, 12-16 years).
  52. 52.  The success rate among the adults was 69% compared with 100% among the young controls. The lower success rate was due to 5 canines that had failed to erupt and 2 canines that had been partially extruded but could not be aligned in the arch. The duration of treating the overall malocclusion of the adults and young subjects did not materially differ. However, the adults showed significant increases in the duration and number of treatment visits required for resolving the canine impaction, in both the simpler and the more difficult cases.
  53. 53.  Conclusion: The prognosis for successful orthodontic resolution of an impacted canine in an adult is lower than in the young patient and that the prognosis worsen with age. Furthermore, when such treatment is undertaken, its successful completion should be expected to take considerably longer.
  54. 54.  M.M. Kuftinec. D Stom, and Y. Shapira : The impacted maxillary canine: Clinical approaches and solutions: Orthodontic and surgical intervention should not be delayed, to avoid unnecessary difficulties in aligning the tooth in the arch. In the most difficult cases of horizontally located canines with the cusp edge in close contact with the roots of the incisors, managing the impacted canine may endanger the incisor roots and failure may be expected.
  55. 55.  It can be generally stated that the impacted canine should be erupted to a site in the mouth that is closest to its impacted position, but consistent with the rule of safe play. That means that the labially impacted teeth should be enchoraged to erupt labially, and those palatally impacted to move through the palatal tissues.
  56. 56.  Palatal arch is a most desirable approach to the correction of many impacted maxillary canines. The palatal arch provides a spring with a relatively low degree of force rate a useful moment to force ratio. This system is usually suitable for treatment of bilateral impactions.
  57. 57.  Surgical approach: Traditionally, most surgical techniques to make access to impacted teeth involved exposure of the entire crown. Extensive surgical procedure was advocated by some, with removal of bone and the dental follicle.
  58. 58.  1. 2. 3. 4. Complications after impaction: Resorption of incisor roots: occurs in 12% of the ectopic eruptions, can be diagnosed at 10 years of age. Follicular cysts Tumorous changes in the follicle Marginal breakdown of supporting bone around adjacent teeth.
  59. 59. Traction hooks used for correcting canine impactions: The “Ballista spring” system for impacted teeth : This system was developed by Harry Jacoby (1979).  The ballista spring is a 0.014”, 0.016”, or 0.018” round wire, which accumulates its energy on its long axis. Its anchorage extremity penetrates in both headgear and edgewise vestibular tubes of the first or second maxillary molars and it is ligated to this tube. Thus the wire cannot rotate in the tubes.
  60. 60.  The horizontal part of the wire accumulates the energy. This part of the wire is attached by a ligature on the first premolar, which allows it to rotate in the slot of the bracket as a hinge axis. The last part of the spring is bent down vertically and ends in an loop shape to which a ligature elastomeric thread can be attached. When the vertical portion of the spring is raised towards the impacted tooth, the horizontal part accumulates the energy into the twisted metal. When the vertical section is released, it bumps down like a “ballista”.
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  65. 65. Advantages of the “ballista spring”: 1. The Ballista spring system uses a spring which creates a vertical traction on the impacted tooth along its long axis thus separating the impacted tooth from the roots of the adjacent tooth. 2. The Ballista spring is easily inserted, ligated and is independent of the other parts of the appliance.
  66. 66. 3. It can be used for buccally as well as palatally impacted canines. 4. In general most systems require full bonded arches at the beginning of the treatment while the Ballista spring does not require any bonding of the anterior teeth till the crown of the impacted tooth erupts completely.
  67. 67. The Monkey hook used for canine impaction:  This was developed by Bowman and Carano (JCO 2002), is a simple auxiliary consisting of a short section of wire with open loops on opposite ends. Intraoral elastics, elastic chain, or NITI coils can be attached to these open loops to produce forces to direct the eruption or rotate the teeth. The loops can be closed with pliers. When linking one hook to another to form a chain or when connecting the Monkey hook to a bondable “loop-button”.
  68. 68.  The loop button: (bondable eyelet) This consists of a 1mm helix of round wire that has been welded or braised to a small diameter, bondable base. Only a small surgical exposure of any surface on the crown of an impacted tooth is required to bond its attachment. If the tooth is deeply impacted, then a second monkey hook needs to be linked to the first.
  69. 69.  Mode of action: Vertical eruptive force: Typical intraarch mechanics to direct the eruption of the impacted teeth utilize reciprocal forces that may tend to tip or intrude the adjacent teeth. In contrast vertical eruptive forces can be created using an intermaxillary elastic stretched from the monkey hook on the arch wire or bracket on a tooth in the opposing dental arch. This arrangement does unfortunately introduce the unpredictable factor of patient compliance with elastic wear.
  70. 70.  Lateral eruptive force: (Slingshot effect) If anchorage is not available from an opposing arch, the intraarch mechanics can be produced using multiple Monkey hooks added to the same loop button attachment; much like keys on a key ring. Elastic chain is attached to one end of the monkey hook and directed to adjacent teeth; thereby, creating a slingshot affect. A closed coil spring is placed on the base arch wire top prevent tipping of the adjacent teeth towards the impacted tooth. A combination of intermaxillary elastic and slingshot effect can be used to provide both vertical and lateral eruptive forces .
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  75. 75. Kilroy spring  This spring is pre-formed module that is simply sliding onto the rectangular arch wire at the site of an impacted tooth. The vertical loop of the Kilroy spring extends perpendicularly from the occlusal plane, in its passive state. A stainless steel ligature is then placed through the helix at the apex of the vertical loop of the Kilroy and then this loop is directed toward the impacted tooth.
  76. 76.  The ligature is tied either directly to the helix of the loop button or to the loop of the Monkey hook that is in turn linked to the loop button attachment.  Mode of action: The Kilroy spring is supported by, 1) the rectangular base arch wire, 2) reciprocal space from the incisal one third of the adjacent teeth where contacted by the lateral extensions of the Kilroy spring. The Kilroy spring need to be periodically retied to maintain a constant force as the tooth is erupting.
  77. 77.  The Kilroy I spring was designed to produce both vertical and lateral eruptive forces for palatally impacted canines. The Kilroy II spring produces more vertical forces and was created for buccally impacted teeth. The amount of force produced by the Kilroy spring can be increased or decreased by bending the vertical loop towards or away from the impacted tooth prior to activation.
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  79. 79. Impacted mandibular canine
  80. 80.  Impacted mandibular canine : Treatment planning: Indications for tooth removal can be interference with planned orthodontic treatment, impingement on adjacent teeth or development of a follicular cyst. In other cases, it may be indicated to have the impacted canine repositioned by surgical or orthodontic means. When none of these treatment modalities are carried out, observation of the impacted tooth is a third possibility.
  81. 81.  Observation of the impacted tooth : In many cases it is acceptable to leave the impacted canine in situ if indications for removal do not exist. The primary canine can continue to function an extended period in some cases. When the impacted teeth is not removed, it should be radiographed periodically to check that pathologic changes have not occurred.
  82. 82.  Exposure and orthodontic repositioning : This treatment should only be carried out if space analysis reveals that the tooth can be brought into occlusion and that deviation of the tooth axis is not too excessive. A measurement of the contralateral erupted canine will indicate whether there is sufficient space; if it is insufficient, additional space may be created orthodontically.
  83. 83.  Surgical removal of tooth: Surgical removal of a mandibular impacted canine is indicated if there is evidence of pathology around the tooth. Another indication is close proximity of the follicle to the marginal periodontium of adjacent teeth. Finally, removal is indicated if there is an orthodontic need to move adjacent teeth into the area.
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  86. 86.  V. Surendra Shetty, gurkeerat Singh : Modified Ribbon arch mechanics in the treatment of ectopically eruptiong canines. (JIOS 2001)  A patient reported to the department with the complaint of irregularly placed lower front teeth.  The mandibular canines were ectopically erupting between the central and lateral incisors. The right canine had already erupted and the left canine bulge could be felt in addition to a slight exposure of its crown.
  87. 87.  It was decided to treat the case without extracting any teeth using the Begg light wire technique.  A segmental co-axial wire was engaged to bring about the derotation of the lateral incisors.  Elastic threads tied to canine loops placed mesial to the premolar brackets, were used to distalise and aid the extrusion of the canines.
  88. 88. Impacted incisor
  89. 89.  Retention and impaction: The overall frequency of permanent incisor retention or impaction in adults has been reported to range from 0.1% to 0.5%. The frequency of maxillary incisor impaction has been found to range from 0.06% to 0.2% and for mandibular impaction a frequency of 0.01% has been reported. The type of incisor most frequently impacted appears to central incisor. the maxillary
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  92. 92.  Timing of removal of supernumerary teeth involves a balance between the risk of injury to the developing permanent incisor and early clearance of the eruption path to prevent space loss.  TREATMENT: Ectopic eruption of incisors: There are various options for extracting the corresponding primary incisor to correct lingual ectopic eruption of mandibular permanent incisors. Mandibular incisors generally erupt in a lingual direction. Furthermore, when the mandibular lateral incisors fully erupts, the intercanine width increases, thus relieving any tendency to crowding.
  93. 93.  Guidelines for managing permanent successors that erupt lingually: If labial migration has not occurred by 8.2 years for the central and 8.4 years for lateral incisor, over retention of the primary incisor exists and its removal should be considered. Only if the primary incisor is firm and the roots have failed to resorb, is extraction indicated.
  94. 94.  Supernumerary teeth: It has been shown that the removal of the supernumerary teeth leads to spontaneous eruption of the involved permanent teeth in 3949% of the cases and emergence takes place after approximately 1½ years. If the permanent incisor is located superficially, exposure of the incisal edge may facilitate eruption. If the permanent incisor is located deeper in the alveolus, clearance of the eruption pathway should be performed.
  95. 95.  Thus, bone positioned coronal to the incisor should be removed; however, the follicle should be left intact unless damage has occurred to this structure, during removal of supernumerary tooth. In such case, bonding of a bracket to the labial surface is indicated, followed by orthodontic traction.
  96. 96.  Impacted normal – shaped incisor : Here, there is a premature loss of primary teeth and the obstacle to eruption is either space loss, the presence of supernumerary teeth or ectopic position of the tooth germ when the tooth has developed into an apical and labial position. If space loss due to crowding or migration of adjacent teeth is the origin of impaction, orthodontic expansion is the treatment choice, and this will lead to spontaneous eruption. If this does not occur, a surgical exposure should be reformed.
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  99. 99.  Impacted malformed incisor: Radiographic examination is important to disclose the extent of malformation so that a decision can be made about whether the tooth should be removed or an attempt should be made to bring it into occlusion. If the tooth is removed, it is important not to injure adjacent permanent tooth germs or interfere with their eruption pathway.
  100. 100.  With crown dilacerated teeth it is important to consider that the crown malformation often prevents normal eruption. Therefore surgical exposure of the malformed tooth is often necessary.  Root angulated teeth should be treated with surgical exposure, orthodontic realignment or autotransplantation so that crown is left in a vertical position. In many instances the presence of supernumerary teeth may lead to curve apices or blunted roots, but does not interfere with the eruption and thus requires no treatment.
  101. 101.  Manuel De Echave – Krutwig, and Leyre Sanchez-Fernandez: Impacted incisors with dilacerated roots: (JCO 2002)  An 18 year old patient presented with two impacted upper central incisor, with dilacerated roots. The intraoral examination reveled class I molar and canine relationship on right side and class II on left side.  The impacted upper central incisors were observed on the panoramic radiograph, both with roots dilacerated toward the distal.
  102. 102.  Treatment planning: Surgical exposure and extrusion of the dilacerated central incisors was planned after explaining the patient that it was impossible to position these teeth correctly without the roots coming into contact with those of the upper lateral incisors, with the consequent resorption of all four roots
  103. 103.  Autotransplantation of permanent maxillary incisors: Danny Gleiser and Clara Jaramillo: (JCO 2002). A female patient presented with a severe class II malocclusion with open bite, excessive overjet, and upper crowding that left no space for the eruption of the left cuspid. A radiograph showed the left permanent incisor inverted 180° on its long axis. A supernumerary was also observed adjacent to the inverted incisor.
  104. 104.  Surgical procedure: The inverted incisor was extracted. A full thickness flap was laid with vertical incisions at the level of the distally adjacent teeth. The gingival periodontal fibers were incised with a scalpel. The alveolar vestibular bone was lifted and left unattached to the base of the flap. The tooth was extracted in the labial direction because its long axis was facing the apex of the adjacent teeth, and extracting it through the alveolus might have damaged the periodontal fibers.
  105. 105.  The incisor socket did not need to be modified because of the recent extraction of the supernumerary tooth. Although the root apex was complete, which was a clear disadvantage.  Stabilization was achieved using .018” standard edgewise brackets and bands and a passive .014” stainless steel arch wire.
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  111. 111.  Osmar Aparecido Cuoghi et al: Extrusion and alignment of an impacted tooth using removable appliances:  Forced orthodontic eruption of an impacted tooth can be performed with either fixed or removable appliances. In fixed appliances the wire attached to the impacted tooth may be more easily deflected than with the removable appliances, causing undesirable movements of adjacent teeth.
  112. 112.  Removable appliances require less chair time, promote better oral hygiene, and are more esthetic, and the forced eruption can start as soon as the appliance is installed.  A female patient presented with the chief compliant of a missing left central incisor. A fixed prosthesis was contraindicated because the patient was likely to have remaining growth potential.
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  116. 116.  Periodontal status following surgical – orthodontic alignment of impacted central incisors with open-eruption technique: S. Chaushu, I. Brin, Y. Ben-Bassat, Y. Zilberman and A. Becker: (EJO 2003). Several factors may effect the outcome of the orthodontic/surgical modality for the resolution of impacted central incisors, but particularly the manner in which the impacted teeth is exposed. 12 subjects (4 males and 8 females), aged 22 years, previously treated for impacted central incisor, were examined 10 years post retention. A split mouth method was used for the comparison with the unaffected side.
  117. 117.  Results showed statistically significant difference between the affected and control incisors in most of the periodontal parameters measured, although some were small and of minimal clinical importance.  The increase in the mesio-labial pocket depth was associated with a highly significant 10% reduction in bone level at this site. A highly statistical increase in crown length and a reduction in the width of attached gingiva were seen in the previously impacted teeth.
  118. 118.  It was concluded that the convenience of the open-eruption technique must be weighted against the long term negative aesthetic and periodontal effects on the treated tooth. Patients should be informed of the possible need for additional periodontal procedures at the end of orthodontic treatment, to improve the aesthetic and periodontal health of the treated teeth.
  119. 119. Management of third molar impaction
  120. 120.  The impaction rate is higher for the third molars than for any other teeth in modern populations.  When the remodeling resorption at the anterior aspect of the mandibular ramus is limited, the eruption of the mandibular third molars might be blocked. (i.e., retromolar space is inadequate.)  The eruption space for the mandibular third molars is also affected by the direction the teeth erupt during the functional phase of eruption.
  121. 121.  Mesial drift of the posterior teeth, because of excessive interproximal attrition, thereby increasing the retromolar space. It is also found that extraction therapy is associated with mesial movement of the mandibular molars.  The average age for third molar emergence ranges from 17 to 21 years, so accordingly, third molar impaction could be diagnosed at around 20 years old.  Some practitioners believe that the mesial pressure of erupting third molars is a significant factor for relapse of incisor alignment are likely to recommend early removal.
  122. 122.  A study was conducted by Tae-Woo Kim et al (AJODO 2003) to confirm that premolar extraction treatment is associated with mesial movement of the molars concomitant with an increase in the eruption space for the third molars and to test the hypothesis that such treatment reduces the frequency of third molar impaction.  Results showed that the impaction for the maxilla and the mandibular third molars were higher for the nonextraction than the extraction patients.
  123. 123.  Dierkes and Faubion (AO 1975, JADA 1968) concluded that only 15% of mandibular third molars erupted in good position after nonextraction therapy.  Richardson (BJO 1975) found that, in nonextraction cases atleast 56% of the mandibular third molars were impacted.  Results also showed that the size of the third molar eruption space associated with a high risk of impaction might be smaller.
  124. 124.  Another study was done by Sinan Ay et al (AJODO 2006) to compare the spontaneous angular and positional changes between the mandibular third molars in patients with asymmetric mandibular first-molar extraction.  The results showed that the prevalence of third molars at the anterior border of the mandibular ramus was significantly greater on the extraction side than on the nonextraction side.  Third molars were positioned more occlusally in the mandible on the nonextraction side than on the extraction side.
  125. 125.  The prevalence of vertically angulated third molars was greater on the extraction side than on the nonextraction side. Conclusion: Mandibular first molar extraction increases the space for mandibular third molar eruption and helps the third molars to move in better position. But early extraction can lead to uncontrolled tipping of the adjacent teeth in to the extraction space.
  126. 126.  Extraoral removal of a lower third molar tooth: ( N. Milner and A. Baker BDJ 2005) In this case a 39 year old was referred to the maxillofacial surgery department with pericoronitis of the lower left third molar. There was a deep pocket distal to the lower left second molar. All other teeth in the lower quadrant were clinically and radiologically assessed as disease free.
  127. 127.  As the patient was experiencing continuing symptoms, the decision was taken to remove the tooth via standard transoral approach, extraction was attempted.  One year following the surgery the patient attended complaining of intermittent pain and swelling. Further imaging using a dentogram revealed the interdental nerve had been displaced buccally and was situated immediately adjacent to the crown of the tooth.  A standard submandibular approach was used and the marginal mandibular nerve identified protected.
  128. 128.  A drill was used to remove the overlying bone on the lingual side of the lower border of the mandible. Through the lingual approach it was possible to visualise the crown of the tooth.  Care was taken to ensure the tooth was disimpacted from the surrounding bone. The crown was elevated followed by the roots.  An extraoral drain was placed to prevent a hamatoma developing and to allow the blood lose from the surgical site to be monitored.
  129. 129.
  130. 130. Impacted first and second molar
  131. 131.  TREATMENT: Delayed eruption: This condition does not involve any treatment apart from continuous observation, because normal, although delayed, eruption is expected to take place. However if signs of eruption obstacles occur the diagnosis should be revised and treatment instituted.
  132. 132.  Ectopic eruption path of the second molar : Treatment of ectopically erupted second molars is important in order to prevent marginal periodontal problems or caries in the contact area with the adjacent molar. When ectopic eruption of a second molar is diagnosed, treatment varies according to the eruption status. Before emergence – a surgical exposure should be attempted if the tooth germ is only moderately displaced.
  133. 133.  When second molars have erupted in an ectopic position, the treatment of choice is orthodontic uprighting, and several orthodontic devices have been described.  In cases with moderate mesial tipping and locking, separating springs or elastics may be used.  With ectopically erupted second molars, distal orthodontic tipping appears to have a significantly better chance of success than mesial tipping. Also horizontal mesially tilted mandibular second molars can be uprighted by orthodontic appliances.
  134. 134.  Yao – Qiang Miao, and Hui Zhong : An uprighting appliance for impacted mandibular second and third molars: In case of missing first molar, the second and third molar are to be moved mesially into the first molar space. But mandibular third molars are the most likely to be impacted, and requires to upright the severely impacted molars. Many appliances have been introduced, but most of them are removable appliances requiring patient cooperation.
  135. 135.  Since 1999, an uprighting appliance have been used for uprighting mandibular second and third molars and also distal tipping without the need for surgery, bone exposure, or splinting.  Appliance construction and activation: A mini-hook is fabricated from .014” stainless steel wire. ( Bend the wire into a circle with a 1.5mm diameter, extending in a perpendicular arm 1.5mm in length. At the top of the arm, bend a hook parallel to the circle.
  136. 136.  Bond the mini-hook conventionally to the distal surface of a horizontally impacted molar or occlusal surface of a mesially impacted molar, so that the hook opens mesially. Make sure the hook does not contact the opposing maxillary molar during closure. Surgical exposure is needed only if a horizontal impaction is so severe that the molar has not erupted at all.
  137. 137.  Solder an .018” stainless steel wire, about 60mm in length, to the middle of the lingual surface of the mesially adjacent molar band. Be sure not to compromise the flexibility of the wire in soldering. Bend the wire at the distolingual corner of the band, extending it 2-3mm buccally, and then turn it distally, making a double or triple-bend push-spring.  Cement the band with the push-spring to the mesially adjacent molar. Stretch the spring 45mm distally, and attach it to the open mesial end of the mini-hook. The push-spring will then exert a distalizing and uprighting force. It should be reactivated until the impacted molar is upright.
  138. 138.
  139. 139.
  140. 140.
  141. 141.
  142. 142.
  143. 143.  Margherita Santoro, Eun – Sock Kim, and Monica Teredesai, and Nikos Karaggannopoulos: Modified removable transpalatal bar for rapid uprighting of impacted second molars: A preformed transpalatal bar shown here offers a mechanically advantageous and efficient solution for uprighting an impacted second molar, especially when bonding a standard tube to the molar would be impossible and other methods would require surgical exposure of the impacted tooth.
  144. 144.  A preformed transpalatal bar is connected to a lingual attachment on the adjacent first molar, then cut and modify according to the clinical situation and the patients anatomy. The bar will not interfere with the occlusion, being positioned on the mandibular retromolar pad and above the occlusal plane of the maxillary second molars. A metal button is bonded as mesially as possible to the available crown surface of the impacted molar. Unless the tooth is completely covered by gingival tissue, surgical exposure of the impacted crown is not required.
  145. 145.  Power chain is connected from the bonded button to the distal extension of the bar, along the distal marginal ridge of the mandibular second molar. Power chain is preferred over bulkier coil springs to ensure patient comfort during mastication, and also because its light intrusive force on the distal marginal ridge prevents overextrusion during the uprighting.
  146. 146.  The power chain greatly accelerates the eruption of the second molar due to the favorable direction of the force vector.  A rigid base arch, .018”x .025” , should be used to stabilize the first molar. As soon as the crown is completely exposed and partly uprighted, a tube is bonded to the buccal surface of the second molar, and a flexible continous arch wire can be applied to facilitate mesial movement of the roots.
  147. 147.
  148. 148.
  149. 149. Management of Impacted premolar
  150. 150.  Treatment planning: The treatment plan should include a cost-benefit analysis of a no treatment approach versus alternatives such as realignment by various surgical or orthodontic means, as well as removal of the unerupted premolar. In many cases, retention of premolars will not be diagnosed initially, first becoming apparent as an accidental finding. The usual treatment is acceptance of the impacted tooth unless a radiographic examination indicates that there is an obvious risk of damage to adjacent structures or definite signs of pathology.
  151. 151.  Observation: Follicular cyst formation may occur, although it is rare. Marginal infection may develop, especially when the crown of the impacted tooth is positioned close to the cervical region of adjacent teeth. Finally, alveolar bone atrophy later in life may expose an otherwise completely impacted premolar and lead to
  152. 152.  Realignment of the impacted premolars : In most cases, realignment of impacted premolars is indicated for functional or esthetic reasons. - Extraction of the primary molar - Extraction of the primary molar and exposure of the premolar with or without follicle removal. - Autotransplantation of the premolar.
  153. 153.  Extraction of the primary molar : when the primary molar and the permanent premolar are in close proximity, i.e., with no or minimal occlusal bone separating the premolar from the primary molar, extraction of the primary molar is indicated to activate and guide the eruption process.
  154. 154.  Extraction of the primary tooth and surgical exposure of the premolar: This approach is usually successful in cases where the axial tilt of the premolar is limited to 45°, whereas exposure in cases where the axial tilt comes close to 90° gives unpredictable results. The principle in surgical exposure is to create a pathway for eruption by removing the bone covering the crown of the tooth germ.
  155. 155.  The coronal part of the follicle represents the definitive eruption mechanism through hard tissue and alveolar mucosa, it should be replaced by an active force (i.e., orthodontic traction). Otherwise the premolar will remain impacted. This dictates two surgical approaches: - Surgical exposure until the follicle is encountered (partial uncovering) - Surgical exposure until the crown is uncovered enamel. (total uncovering)
  156. 156.  Surgical repositioning: If the tipping of the premolar tooth germ is not too extreme and root formation not too advanced, surgical repositioning by a tipping procedure is a possibility. After removing the primary predecessor and sufficient bone in the intended displacement direction, the tooth is tilted into its new position using an elevator. If the tilt of the premolar is approximately 90 °, this treatment alternative will not yield satisfactory results and surgical repositioning of the tooth germ, indicated.
  157. 157.  This treatment consists of atraumatic tooth removal and repositioning so that eruption into the normal position is possible.  Due to the usual lingual tilt of both mandibular and maxillary premolar impactions, a lingual approach is generally necessary.
  158. 158.
  159. 159.
  160. 160.
  161. 161.  Yuko Taniomoto et al: Orthodontic treatment of a patient with an impacted maxillary second premolar and odontogenic keratocyst in the maxillary sinus: (AO 2005)  An eight year old girl was brought to the orthodontic clinic of Okayama university.  The patient had an impacted upper left second premolar because of an odontogenic keratocyst and showed a skeletal class II jaw relationship.  At age of 6 years marsupialization of a cyst was performed, because the patient had shown a swelling in the left cheek.
  162. 162.  At the age of 9 years, after regaining the space for the eruption of the premolar, the impacted premolar erupted without traction.  At 12 years, edgewise treatment was initiated, which continued for three years.
  163. 163.
  164. 164.
  165. 165.  Complications: - Pulp necrosis: subsequent to repositioning is the consequence of unsuccessful revascularization of the transplant, and this event is primarily related to the size of the apical foramen. In case of pulp necrosis, a lack of periapical healing is usually diagnosed one or two months postoperatively.
  166. 166.  Root resorption: This is result of trauma to the root surface during root removal, and this complication is primarily related to the stage of tooth development at transplant removal. Surgical repositioning in stages when root development is complete and the expected eruption time has been exceeded often leads to progressive root resorption. Surgical repositioning generally leads to limitation of root growth, usually about 2mm reduction in potential root length, which is usually of minor practical importance.
  167. 167.  In conclusion, surgical repositioning of ectopic premolars appear to be reasonably successful procedure that should be considered when the ectopic position deviates 90° or more from normal.
  168. 168. conclusion  The management of tooth impaction, generally speaking ascends from acceptance of the situation to the removal of the impacted tooth concerned.  When the situation is considered acceptable, periodic X-ray examination will be conducted to check the tooth position, primary tooth root resorption, occlusal position, and for evidence of pathological changes. With this non-invasive “wait and see” approach, future treatment options are still open.
  169. 169. References:  William R. Proffit, Henry W. Fields, and James L. Ackerman: Contemporary Orthodontics: Third edition. 2000.  Thomas M. Graber, Robert L. Vanarsdall, and Katherine W.L. Vig: Orthodontics: Current principles technique. Fourth edition. Elsevier Mosby: 2005.  Jens O. Andreasen, Jens Kolsen Petersen, and Daniel M. Laskin: Textbook and color atlas of tooth impactions. Diagnisis, Treatment, and prevention: First edition. 1997.
  170. 170.  Samir E. Bishara: Impacted maxillary canines: A review. AJODO 1992; vol 101: Page 159-71.  Charles A. Frank: treatment options for impacted teeth: JADA May 2000; vol 131: Page 623-632.  Sanjay Suri, Ashok Utreja, and Vidya Rattan: Orthodontic treatment of bilaterally impacted maxillary canines in an adult: AJODO 2002; vol 429: Page 429-37.
  171. 171.  Kazem Al – Nimri and Tareq Gharaibeh: Space conditions and dental and occlusal features in patients with palatally impacted maxillaary canines: and aetilogical study. EJO 2005; vol 27: Page 461-465.  P.J. Wisth, K. Norderval, and O. e. Boe: Periodontal status of orthodontically treated impacted maxillary canines: AJO January 1976; vol 46:Page 69-76.  Rozmary Mark D’Amico, Krister Bjerkin, Juri Kurol, and Babak Falahat: Long term results of orthodontic treatment of impacted maxillary canines: AO 2003; vol 73: Page 231-238.
  172. 172.  M.M Kultinec, D Strm, amd Y. Shapira: The impacted maxillary canines: I. Review of concepts. Journal of dentistry for children September-october 1995: Page 317-324.  M.M Kultinec, D Strm, amd Y. Shapira: The impacted maxillary canines: II. Review of concepts. Journal of dentistry for children September-october 1995: Page 325-334.  V. Surendra Shetty, Gurkeerat Singh: Modified ribbon arch mechanics in the treatment of ectopically erupting mandibular canines: A case report. JIOS 2001; vol 34: Page 20-23.
  173. 173.  S. Jay Bowman, and Aldo Carano: The Monkey hook: An auxiliary for impacted, rotated, and displaced teeth: JCO 2002; vol 35: Page 375-378.  Jay Bowman, Aldo Carano: Canine obedience training: Monkey hook and Kilroy spring. JIOS 2003; vol 36: 179-184.  Harry Jacoby: The “ballista spring” system for impacted teeth: AJO february 1979; vol 75: Page 143-151.
  174. 174.  R. Kontham, T.M. Bhagtani. P.V. Wadkar: The “Ballista Spring” for impacted canine: JIOS 2000; vol 33: Page 21-23.  Margherita Santoro, Eun-Sock Kim, Monica Teredesai, and Nikos Karaggiannopoulos: Modified removable transpalatal bar for rapid uprighting of impacted second molars: JCO september 2002; vol 36: Page 496-499.  Danny Gleiser, Clara Jaramillo: Autotransplantation of a permanent maxillary incisor: JCO 2002; vol 36: Page 671-675.
  175. 175.  V. Ravinder, Nikar Anand Verma, Ashima Valiathan: 3 – Dimensional computed tomography: A new method for location of impacted canines: JIOS 2002: vol 35: Page 7375.  Ashima Valiathan, Siddhartha Dhar, Nikhar Verma: 3D imaging in orthodontics: Adding a new dimension to diagnosis and treatment planning: Trends In Biomaterial and Artificial Organ 2006, (in press)  Jon Artun, Faraj Behbehani, Lukman Thalib: Prediction of maxillary third molar impaction in adolescent orthodontic patients: AO 2005; vol 75: Page 904-911.
  176. 176.  PatricK P.C Lee: Impacted premolars: Dent Update 2005; vol 32: Page 152-157.  Yuko Tanimoto, Shouichi Miyawaki, Mikako Imai, Ryoko Takeda, Teruko TakanoYamamoto: Orthodontic treatment of a patient with an impacted maxillary second premolar and odontogenic keratocyst in the maxillary sinus: AO 2005; vol 76: Page 1077-1083.  N. Milner and A. Baker: Extraoral removal of a lower third molar tooth: BDJ september 2005; vol 24: Page 345-346.
  177. 177. Thank you Leader in continuing dental education