Management of Impacted Maxillary Canines PDF

MANAGMENT OF IMPACTED MAXILLARY CANINES By Dr lanya sardar 16 August, 2024 Overview Abstract Research Methodology Background Results & Discussion Objectives Conclusion Literature Review Future Research Introduction Prop...

MANAGMENT OF IMPACTED MAXILLARY CANINES By Dr lanya sardar 16 August, 2024 Overview Abstract Research Methodology Background Results & Discussion Objectives Conclusion Literature Review Future Research Introduction Proper canine development and positioning are crucial for dental function and stability. Impacted maxillary canines, which occur in 1-3% of the population, are more commonly displaced palatally and are seen more often in females and Caucasians. Early diagnosis and intervention are essential for optimal outcomes, as disturbances in eruption can affect long-term dental health. Bilateral impactions are less frequent, making up about 8% of cases. Causes of the canine impaction Longest Development & Eruption Path: Maxillary canines have the longest period of development and eruption. Initial Development: Development begins high in the maxilla, just under the orbit. Crown Mineralization: Starts at 4–5 months postnatal. Root Development: Begins around age 4–6 years and completes after age 10–11. Eruption Order: Canines erupt after the first premolars. Eruption Disturbances: These factors can contribute to disturbances in the eruption path. Pathological conditions such as Supernumerary teeth, Odontomas, Trauma during early development ,Cleft lip and palate  Etiology Two theories explain canine impaction: 1.Guidance Theory: Suggests that the eruption of the canine is guided by the root of the lateral incisor, and any disruptions in the development or eruption of the incisors can affect the canine's eruption. 2.Genetic Theory: Proposes that hereditary factors may cause anomalies like agenesis or malformation of permanent teeth, leading to canine impactions. Peck et al. found that an absent or abnormal lateral incisor root can prevent the maxillary canine from erupting properly.  Al-Nimiri and Gharaibeh: Noted wider transverse arches in the impaction group. Yan et al.: Found no link between maxillary width and palatal displacement but saw a connection between buccal impactions and narrow arches. Hong et al.: Concluded that maxillary width doesn’t affect palatal displacement but found higher rates of tooth agenesis in those with displaced canines.  Diagnosis with CBCT 3D Imaging (CBCT): Essential for precisely locating impacted maxillary canines and planning both surgical access and orthodontic movement. Precision: CBCT provides detailed information about the canine’s position, size, and shape, which is crucial for determining space requirements and considering canine substitution in cases of missing lateral incisors. Root Issues & PDL Absence: CBCT can reveal root dilacerations or the lack of a periodontal ligament, which may signal ankylosis and hinder proper canine movement. Treatment Strategy: By obtaining this data in advance, clinicians can better assess risks and limitations, ensuring a tailored treatment approach for each patient.  DETERMINING IMPACTED CANINE CROWN AND ROOT MORPHOLOGY WITH CBCT CBCT technology provides precise details about the shape and size of the impacted maxillary canine crown before treatment begins, which is essential for planning intra-arch space and considering canine substitution for missing lateral incisors. It can also reveal root dilacerations and the absence of a periodontal ligament (PDL) space, which may indicate ankylosis and hinder the movement of impacted canines into their ideal position. DETERMINING THE PROXIMITY OF AN IMPACTED CANINE TO THE ROOTS OF ADJACENT TEETH Maxillary canine impactions increase the risk of root resorption in adjacent teeth both before surgical exposure and during orthodontic movement. It is believed that factors like an enlarged or active dental follicle and pressure from the erupting tooth may contribute to this resorption. However, no clear association has been found between the size of the dental follicle of unerupted maxillary canines and root resorption of the maxillary incisors. Dental follicles of ectopically positioned canines tend to be wider and more asymmetric compared to those of normally erupting canines. DETERMINING THE PROXIMITY OF AN IMPACTED CANINE TO THE ROOTS OF ADJACENT TEETH DETERMINING THE PROXIMITY OF AN IMPACTED CANINE TO THE ROOTS OF ADJACENT TEETH DETERMINING THE PROXIMITY OF AN IMPACTED CANINE TO THE ROOTS OF ADJACENT TEETH  3D ORIENTATION OF THE IMPACTED MAXILLARY CANINE Impacted maxillary canines can be positioned buccally, palatally, or centrally in the ridge, and CBCT imaging should use multiple planes—axial, sagittal, coronal, and 3D reconstructed views—for accurate localization. Relying on just one plane may lead to incorrect identification, such as misjudging the buccolingual position, which cannot be determined from coronal slices alone. For example, while the coronal view may show a palatal position, other views like axial, sagittal, and 3D can confirm a buccal position. CBCT also helps differentiate between vertical and horizontal positions of impacted canines, which is essential for planning surgery, determining biomechanics, and estimating treatment time. 3D ORIENTATION OF THE IMPACTED MAXILLARY CANINE CBCT images are also helpful to differentiate vertical versus horizontal position of the ectopic maxillary canines in both sagittal and transverse planes (Figs 10-11 and 10-12). This is critical for planning surgical access and biomechanics and estimating treatment duration.  Depth of impaction Superficial soft tissue impactions Partial intraosseous impactions Deep full bony impactions Deeper impacted canines may take longer to align with the arch and may require bonding during surgery to prevent soft tissue overgrowth. Pre-treatment information, including the size and shape of enlarged dental follicles, is crucial and can be accurately assessed using 3D imaging. This helps in selecting the appropriate exposure technique and orthodontic mechanics. Depth of impaction  Depth of impaction Enlarged dental follicles can lead to root resorption of adjacent teeth, making it important to assess follicular size before surgery. Proper surgical exposure requires removing follicular tissue and recontouring bone to ensure proper soft tissue adaptation, as incomplete bone removal can obstruct tooth movement. ext 3D SIMULATION OF TOOTH MOVEMENT Recent advances in 3D reconstruction software allow virtual tooth movement simulations before treatment. This is particularly helpful for severely displaced impacted canines, aiding the decision of whether to save or extract the tooth. which allows for calculation of two important parameters; Interradicular space: Needed for safely moving the impacted tooth into the arch. Intra-arch space: Required for optimal positioning of the impacted tooth in the arch. 3D SIMULATION OF TOOTH MOVEMENT 3D SIMULATION OF TOOTH MOVEMENT EARLY DETECTION AND INTERCEPTION OF ECTOPIC GROWTH OF MAXILLARY CANINES WITH CBCT CBCT images can accurately detect ectopic growth and maxillary hypoplasia in early canine development. There is a strong link between maxillary transverse deficiency and buccal canine impactions, and palatal expansion before root formation can help prevent labial impactions. Early rapid palatal expansion is also effective in promoting the eruption of palatally displaced canines. An example case shows an 11- year-old girl with crowding, where CBCT confirmed transverse deficiency and ectopic canine growth. EARLY DETECTION AND INTERCEPTION OF ECTOPIC GROWTH OF MAXILLARY CANINES WITH CBCT  EARLY DETECTION AND INTERCEPTION OF ECTOPIC GROWTH OF MAXILLARY CANINES WITH CBCT A 13-year-old girl with a history of a buccally impacted maxillary right canine. (a) Pretreatment panoramic radiograph showing an impacted maxillary right canine with an enlarged follicle overlapping the root of the lateral incisor and insufficient intra-arch canine space. (b) Clinical photograph captured several months after surgical exposure demonstrating the buccal position of the right canine and flared maxillary anterior teeth. EARLY DETECTION AND INTERCEPTION OF ECTOPIC GROWTH OF MAXILLARY CANINES WITH CBCT A periapical radiograph taken at the same visit showed root resorption and bone loss on the distal root surface of the maxillary right lateral incisor as well as root proximity between the right lateral and central incisors. 3D-Guided Classification of Maxillary Canine Impactions CBCT imaging plays a crucial role in assessing the complexity of impacted maxillary canines. Kau et al. developed the KPG index, the first 3D classification system for these impactions. The index evaluates the severity of displacement of the canine crown and root tip in three planes: horizontal (x), vertical (y), and axial (z). It categorizes the difficulty of treatment into four levels: easy, moderate, difficult, and very difficult.  3D-Guided Classification of Maxillary Canine Impactions Korbendau classified palatally impacted canines into three categories based on the position of the crown: 1.The crown is near its typical position within the arch. 2.The crown is positioned across the root of the lateral incisor. 3.The crown is located near the median palatine suture. These categories are further divided into deep and superficial impactions, depending on the depth and orientation of the canine within the palate. 3D-Guided Classification of Maxillary Canine Impactions Maxillary canine impactions present an increased risk of root resorption in teeth adjacent to an impaction prior to surgical exposure and during orthodontic tooth movement. It has been shown that physical proximity of less then 1 mm between the maxillary impacted canine crown and an adjacent root is correlated with root resorption. In addition during the management of maxillary canine impactions, loss of periodontal attachment may develop in exposed canines and/or neighboring teeth which is is multifactorial and it is often related to the surgical approach, accelerated traction, heavy forces, or poor oral hygiene. It may also be observed when exposed canines or orthodontic traction devices come in contact with adjacent roots or tooth-supporting structures. Every effort should be made to avoid these complications. Knowing the spatial relationship of the impacted canine to the neighboring teeth prior to and during tooth movement will assist in minimizing these risks. Avoiding these complications will often require early exposure of impacted maxillary canines with an open approach and their movement utilizing light forces away from neighboring teeth. 3D-Guided Classification of Maxillary Canine Impactions 3D-Guided Classification of Maxillary Canine Impactions  TYPE A (HIGH RISK) A high risk of root resorption and periodontal damage to adjacent teeth. Subtype I: Impacted canine that has caused root resorption in an adjacent tooth prior to treatment Subtype II: –Impacted canine that is positioned in close proximity to the roots of adjacent teeth (less then 1 mm) –Impacted canine that is positioned a safe distance from adjacent roots (more then 1 mm) but whose movement directly into the arch may position it in close proximity to adjacent teeth –Impacted canine that is initially positioned a safe distance from adjacent roots (more then 1 mm) but whose proximity to neigh- boring teeth will increase with orthodontic alignment –Impacted canines with enlarged dental follicles TYPE A (HIGH RISK) While it remains controversial, enlarged follicles around impacted canines may contribute to root and bone resorption due to their osteoclastic and cementoclastic activity. As a precaution, impacted canines with enlarged follicles should be classified as high-risk Type A impactions. These impactions require immediate exposure and careful movement of the canine away from adjacent teeth, typically using an open surgical approach to allow for better control of the tooth's movement. Maxillary teeth in close proximity to impactionsmust be bypassed in the archwire until the crowns of the uncovered canines are positioned a safe dis- tance from the adjacent roots. When proximity to the neighboring teeth is related to the maxillary deficiency in the intercanine area, palatal expansion may be necessary to create sufficient interradicular and intra-arch space to allow healthy traction and positioning of the impacted canine in the arch. TYPE B (LOW RISK) This group presents a low risk of root resorption and periodontal damage to adjacent teeth prior to or during orthodontic tooth movement. In Type B cases, the impacted maxillary canine can be safely moved directly into its designated position once it is surgically exposed. Under these circumstances, anchorage preparation will determine the optimal timing for canine exposure.  Preventive Intervention roviding an environment that is most favorable for natural eruption is the first treatment of choice. In some situations, intra-arch space creation will allow physiologic eruption of the maxillary canines without a need for surgical intervention. Extraction of Primary Canine: extracting the primary maxillary canine can allow for the natural eruption of an ectopically growing permanent canine. Success Rate: If the ectopic canine crown does not cross the midline of the lateral incisor, extraction before age 11 has a 91% success rate for natural eruption. Lower Success Rate: If the ectopic canine crosses the midline of the lateral incisor, the success rate drops to 64%. When to Avoid Extraction: If the ectopic canine's crown is past the mesial root of the lateral incisor, extraction of the primary canine will not result in self- correction, and surgical intervention is necessary. Preventive Intervention Additional Extractions: Alessandri Bonetti et al. found that extracting both the primary maxillary canines and first molars is more effective in preventing palatal or central canine impactions than extracting only the primary canines. Palatal Expansion: In cases of narrow maxilla or arch length deficiency, palatal expansion can help correct ectopically positioned canines and facilitate their natural eruption. Surgical Intervention: If preventive measures fail and the canine remains ectopic, surgical intervention is required. Surgical and Orthodontic Treatment Review of the patient’s medical history along with a clinical and radiographic examination is essential Providing adequate periodontal support with maintenance of hard and soft tissue integrity has to be considered with this method. age, patient motivation, adequate hygiene, evalu- ation of adequate space, position of the canine, and whether the dentition is favorable for orthodontic manipulation. If factors exist that would limit surgical exposure or the time of treatment to achieve an acceptable result, the options of maxillary canine extraction and maxillary premolar substitution, possible retention of the primary maxillary canine, autotransplanta- tion, and future implant placement may also have to be considered. Surgical and Orthodontic Treatment Horizontal impactions with full root formation, ankylosis, and root dilacerations often present poor treatment prognoses and will require extractions with alternative treatment options. In some situations, ankylosed maxillary canines may be mobilized with luxation during surgical exposure and immediate application of orthodontic traction. Incor- rect surgical exposure and orthodontic movement will often lead to attachment loss on the exposed maxillary canine or on adjacent teeth, root resorption, and prolonged treatment time In Type A impactions where there is an increased risk of root resorption or attachment loss in adjacent teeth, surgical intervention must precede orthodontic tooth movement. In these situations, temporary anchorage devices (TADs) may be utilized for anchorage. The size and location of the TAD can be determined as part of the 3D orthodontic and surgical treatment planning.  Management of palatally impacted and displaced maxillary canines The surgical exposure precedes the initiation of orthodontic treatment. With this method, a full-thickness muco- periosteal flap is elevated on the palate, and bone is removed from all areas covering the enamel surface up to the cementoenamel junction (CEJ). The flap is repositioned, and the portion of the flap cover- ing the maxillary canine is excised. This method essentially allows the impacted canine to self-erupt. Surgical Management of Labial Impactions There are three surgical techniques for labially impacted maxillary canines are: 1.Gingivectomy/Excision 2.Apically Positioned Flap (APF) 3.Closed Eruption Surgical Management of Labial Impactions Studies found that excisional approach to result in less favorable peri- odontal outcomes compared to an APF Smaller risk of ankylosis and shorter treatment times with the open versus closed surgical technique. Orthodontic movement in the presence of inflam- mation poses great risks of attachment loss.47 The mucogingival junction (MGJ) separates the attached masticatory and alveolar mucosa. Labially impacted maxillary canines may be positioned at a differ- ent height in relationship to the MGJ canine must be performed with strong consideration of its position relative to the MGJ in order to avoid mucogingival problems around exposed teeth. To help achieve this objective, Levin and D’Amico50 and Vanarsdall and Corn47 proposed the APF for uncov- ering labially impacted teeth. TECHNIQUE TO PROJECT THE MGJ ON CBCT IMAGES To identify the precise position of the impacted maxillary canine to the MGJ, a combined technique utilizing clinical and 3D evaluation must be applied GINGIVECTOMY/EXCISION It is simple technique It considered to be the least invasive, it is technique sensitive. Improper identification of the impacted maxillary canine and the incision design might compromise the uncovered tooth periodontally.indicated in soft tissue impactions only when no bone is covering the crown of the impacted tooth and at least two-thirds of the crown is positioned coronal to the MGJ. Indication; performed for labially impacted maxillary canines in both upright and angulated positions when an adequate band of gingiva is present to allow for preservation of keratinized apical gingiva of 3 to 4 mm in width on the exposed crown Contraindication; when more than one-third of the crown of the impacted maxil- lary canine is positioned apical to the MGJ and when any bone removal overlying this crown is required. In these situations, flap reflection is mandatory to complete proper exposure. Bonding of the attachment to the exposed crown and initiation of traction may be done at the time of exposure or after completion of soft tissue healing. Procedur Everyeprecaution has to be made to prevent exposure of the CEJ of the impacted canine with this technique. Adequate gingival width of at least 3 to 4 mm must be preserved apical to the exposure area to prevent development of mucogin- gival problems. Although this technique may be accomplished with a surgical blade, laser, or electrosurgical unit the use of a blade will allow minimal tissue damage and remodeling. Blade incision is per- formed with an internal bevel to allow optimal soft tissue adaptation to the exposed crown Excessive removal of tissue may cause gingival shrinkage to the MGJ that will lead to recession and absence of attached gingiva Bonding of the attachment to the exposed crown and initiation of traction may be done at the time APICALLY POSITIONED FLAP In order to provide an adequate band of masticatory mucosa around the exposed maxillary canine, this technique utilizes the concept of a soft tissue pedicle graft where the coronal portion of the keratinized gingiva is released from the incisal, mesial, and distal aspects but remains attached at the apical base. The pedicle flap is then repositioned apically to cover the cervical third of the exposed crown. It is the most technique-sensitive exposure procedure and requires thorough knowledge of periodontal anatomy and skills in periodontal plastic surgery. Improperly applied or performed APF may lead to unesthetic outcomes and gingival recession. Indication;when at least half of the crown of the impacted canine is positioned apical to the MGJ Contraindication; This technique essentially has no contraindications. Success rate; dependent on the blood supply in the dissected marginal keratinized gingiva and relates to the pedicle thickness and incision design. Initial healing allows time for epithelialization and for reattachment of the soft tissue before orthodon- tic forces are applied. An orthodontic attachment can be bonded a week to 10 days postsurgery, and light forces can be applied at that time. CLOSED ERUPTION Closed eruption is a surgical exposure technique whereby the flap is repositioned back to cover the surgically accessed tooth after an attachment (gold chain) is bonded to it. Indication; This technique is indicated for high vertically posi- tioned maxillary canines that do not overlap the roots of adjacent teeth (Type B) and can be erupted by tracking directly into the arch. In case of deep alveolar impaction Contraindication; Type A where the impacted maxillary canine is angulated and positioned over the roots of the adjacent teeth due to the risk of root resorption or bone loss in adjacent teeth Bonding of attachment; the attachment is bonded at the time of surgery May cause soft tissue scarring, which may slow down orthodon- tic movement. Connective tissue may also in-grow into the gold chain, causing pain during activation. Surgical Management of Palatal Impactions Surgical intervention of palatal impactions can be managed via two techniques: excision and closed eruption. both techniques pre- sent with similar esthetic and periodontal outcomes; however, the open approach offers a shorter treat- ment time and a smaller risk of ankylosis Excision; This approach is indicated for Type A and Type B impactionswith no contraindications and An attachment may be bonded during the surgical exposure or after completion of soft tissue healing. Closed eruption;is indicated in Type B impactions only, Postsurgical Orthodontic Management of Impacted Maxillary Canines Orthodontic movement of the exposed maxillary canine is impossible without an intact PDL. Canine mobility should also be checked during every surgical exposure Exposed canines require activation with continuous light force. This is achieved by activation intervals every 2 to 3 weeks utilizing elastic threads or elastomeric chains. Requires proper intra-arch space opening, adequate anchorage control, and utilization of special auxiliaries for continuous activation.  Postsurgical Orthodontic Management of Impacted Maxillary Canines SPACE-OPENING CONSIDERATIONS Intra-arch canine space should be created by addressing causative factors. ANCHORAGE CONSIDERATIONS Ectopic position as well as prominent root anat- omy of the maxillary canines can present significant resistance to orthodontic traction  Orthodontic anchorage for the management of impacted canines Tooth-Supported Tooth-Free Combination of Tooth- Appliances Appliances Supported and Tooth- Free Appliance Rigid stainless steel archwires TADs (Temporary Anchorage Combination appliances include Transpalatal bars Devices) the use of indirect anchorage, Ligature twisted wires TAD-Supported Appliances when exposed maxillary Nance appliances TAD-supported canines are acti- vated to the RPEs (Rapid Tooth-supported rapid palatal archwire or directly to the teeth Palatal Expanders) expanders (RPEs); Hyrax RPE, that have been reinforced with Bonded RPE ,Haas RPE TADs to prevent unnecessary tooth movement Palatal view of Type A palatally impacted canines shortly after surgical exposure with an open approach activated to the transpalatal twisted ligature wire in the posterior downward direction away from the maxillary incisor roots. ACTIVATION CONSIDERATIONS When planning the activation of forces for impacted maxillary canines, it's crucial to consider the direction of tooth movement. In Type A impactions, the exposed canines must first be moved away from neighboring teeth, with deeply positioned canines requiring eruption into the oral cavity before they can be repositioned in the arch. Various auxiliaries can be used to facilitate this movement, including elastomeric chains, elastomeric threads, nickel-titanium coils, and custom-made springs such as the swinging gate. Activation can be achieved through attachments like islets and brackets, with forces applied directly to the archwires, transpalatal auxiliaries, or TADs. LABIAL IMPACTION CONSIDERATIONS For a low-positioned labial impaction, it is possible to piggyback a light NiTi wire onto the base arch and extrude the canine into the arch position is too apical, vertical traction via an attach- ment and a power thread tied directly to the base arch is needed. If the canine is positioned directly over the lateral incisor, distal force may be appro- priate in conjunction with a labial vector guiding the canine away from the lateral incisor. This may be accomplished via a swinging gate PALATAL IMPACTION CONSIDERATIONS Based on the depth of the impaction and the dis- tance from the optimal position in the arch, palatally impacted maxillary canines may be activated either directly to the archwire or to anchorage devices posi- tioned on the palate. The position of the palatally impacted canine can be related to the paramid- palatal line in the axial plane A palatally impacted canine positioned distal to the paramidpalatal line (right canine may be directly activated to the archwire due its close proximity to the ideal position in the arch. palatally impacted canines positioned mesial to the paramidpalatal line indi- cate their further displacement and need for vertical activation to anchorage auxiliaries positioned on the palate CONSIDERATIONS FOR TIMING OF EXTRACTION OF OVERRETAINED PRIMARY CANINES Patients with impacted maxillary canines often present with overretained primary canines. extractions of the primary maxillary canines may be helpful in preventing impactions in the early stages of permanent maxillary canine root development When maxillary canines are positioned further away from their ideal location in the arch, extraction of the overretained primary canines may be postponed until the exposed canines are moved closer to their optimal position Conclusion Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nullam interdum hendrerit magna et molestie. In in blandit lorem. Vivamus porta varius orci, eu dapibus urna vestibulum in. Maecenas lobortis condimentum mi, ut gravida purus facilisis ac. Pellentesque sodales turpis turpis, eget faucibus ligula bibendum et. Integer eu congue nisl. Sed sagittis vel nunc sed porttitor. Donec posuere felis lacus, sit amet tincidunt metus blandit quis. Praesent nec cursus turpis, eu elementum felis. Pellentesque sodales turpis turpis, eget faucibus ligula bibendum et Thank You Thank you for watching