1 Introduction
Canines are not just fundamental to the mechan- ics of biting and chewing but also hold significant value in facial aesthetics. The phenomenon of canine impaction is a dental predicament where the root of the permanent tooth is entirely devel- oped, yet it fails to erupt in alignment with the dental arch [1]. This condition, particularly con- cerning the maxillary canines, is not as rare as one might assume. With a reported prevalence of 1.7–4.7%, maxillary canine impaction stands as the second most common impaction after the third molars.
The etiology behind maxillary canine impac- tion is multifaceted. Often, it is attributed to the delayed eruption sequence, where the eruption of the premolars precedes that of the canines. This phenomenon can be exacerbated by several fac- tors, including the positioning of adjacent teeth, discrepancies in arch length, and disproportionate tooth size. Contrarily, palatal impaction of maxillary canines leans more toward a genetic predisposition. On the other hand, mandibular canine impaction, while less frequent, typically ensues post the impaction of the third molars in the mandible. The primary culprits for this are believed to be an abnormal positioning of the tooth bud, along with the potential lack of arch space and an oversized canine crown
Addressing impacted canines is a multifaceted process that necessitates a tailored approach for everyone. The management spectrum ranges from early interceptive strategies to more inva- sive surgical interventions. For cases with an anticipated permanent canine impaction, an early interceptive approach is recommended. This involves the extraction of the primary canine to make way for the permanent one, supplemented by orthodontic treatments such as rapid maxillary expansion and headgear usage. These interventions aim to create sufficient space and foster the normal eruption of the permanent canine.
For more stubborn cases, surgical exposure is a viable option. This technique entails the eleva- tion of a gingival flap to expose the impacted canine. Subsequently, an orthodontic button is attached to the crown, and a gold chain is employed to gradually pull the tooth into its rightful position through forced eruption. In sce- narios where neither interceptive nor surgical methods are viable or preferred, alternatives like artificial transplantation or extraction of the impacted canine are considered [8]. Understanding the complexity of impacted canines and the nuances of their management is crucial for dental practitioners. This chapter aims to dissect these techniques, offering insight into their methodologies, applicabilities, and poten- tial outcomes. The goal is to enhance the clini- cian’s ability to effectively manage this common yet challenging dental condition.
2. Extraction of Impacted Canine
1. Extraction Technique of Impacted Maxillary Canine
In certain clinical scenarios, the natural eruption of an impacted maxillary canine is deemed highly unlikely, particularly when the space designated for the canine has closed, rendering orthodontic space creation both time-intensive and financially burdensome. In these instances, extraction of the impacted canine may be considered a more feasible option to maintain the current occlusion (Fig. 5.1). However, this decision should always be made in consultation with the patient and their guardians, ensuring a thor- ough understanding of the procedure’s impli- cations. Moreover, the presence or potential development of a cyst around the crown of the impacted canine further necessitates its extraction.
2. Surgical Procedure :
(a) Incision: The choice of incision—sulcular, vestibular, or mucogingival junction—is contingent upon the location of the impacted canine. For palatally impacted canines, a palatal approach may be required. The incision, typically 1–2 cm in length, should be ample to reveal the crown of the tooth fully.
(b) Flap elevation: A full-thickness flap ele- vation is performed to provide a clear view of the impacted tooth and surround- ing bone. Achieving adequate hemostasis during this step is crucial to minimize bleeding and improve visibility.
(c) Bone grinding or removal: In many cases, the labial bone covering the crown of the canine is either perforated or presents as a thin film. Here, bone curettes are effective for removal. However, if the bone is sig- nificantly thicker, drilling may be neces- sary to access the crown.
(d) Odontomy: This step is generally not required for children. However, adults with impacted canines often present with ankylosis, necessitating the division of the tooth. A high-speed bur is used at the cervix of the tooth to perform odontomy, facilitating easier extraction.
(e) Extraction using elevator: An extraction elevator is employed to separately remove the crown and the root of the tooth. This method ensures a more controlled and precise removal, especially in complex cases.
(f) Hemostasis: Post-surgical bleeding can lead to swelling and bruising, which are common concerns for many patients. Effective hemostasis is essential to pre- vent these complications and ensure a smoother recovery.
(g) Closure: The choice of suture material varies with the patient’s age. In children, absorbable 4-0 vicryl is preferred for con- tinuous suturing, which negates the need for stitch removal. Conversely, adults may require suturing with materials like silk or nylon for optimal healing
The extraction of impacted maxillary canines is a complex procedure that requires a meticulous approach and should be considered when other orthodontic interventions are deemed impractical or unfeasible. The technique involves several critical steps, each requiring careful exe- cution to ensure the patient’s safety and the pro- cedure’s success. As with all dental procedures, informed consent and a comprehensive under- standing of the patient’s medical history are par- amount. This technique offers a viable alternative to traditional orthodontic interventions, provid- ing relief and a path forward for patients with impacted canines
3 Observation Without Extraction
In certain clinical circumstances where the space designated for an impacted canine has been occluded by the eruption of permanent premo- lars, and the overall maxillary and mandibular occlusion appears normal, opting for a conserva- tive approach by simply monitoring the condition may be considered appropriate. This noninvasive strategy is contingent upon a comprehensive evaluation of the patient’s dental health and a bal- anced risk-benefit analysis
1. Communicating with Patients and Guardians
(a) Informed decision-making: Central to adopting a watchful waiting strategy is the thorough communication with the patient or their guardians. They must be fully apprised of the condition, its poten- tial progression, and the implications of choosing observation over immediate extraction.
(b) Potential risks: It is imperative to discuss the possibility of cyst formation or inflammation around the impacted canine. While these risks might not necessitate immediate action, understanding them is crucial for future monitoring and decision-making.
(c) Implications for future dental procedures: The presence of an impacted canine can complicate future dental interventions. For instance, if the tooth above the impacted canine is lost and implant place- ment is required, the impacted canine might present challenges. Discussing these scenarios helps in planning future dental care and setting realistic expectations.
2. Monitoring Strategy :
(a) Regular checkups: A structured schedule for dental checkups is crucial to monitor the status of the impacted canine. These visits allow for timely detection of any changes or developments that might necessitate intervention
(b) Imaging and diagnostics: Periodic imaging, such as X-rays or CT scans, may be employed to keep a close watch on the position of the impacted canine and the health of surrounding tissues.
(c) Assessing changes in condition: Any signs of cyst formation, inflammation, or shifts in the position of the impacted canine should be meticulously recorded and assessed. Changes in the patient’s symptoms or discomfort levels should also be noted.
3. Decision-making Over Time
(a) Reevaluation: The decision to continue with observation should be regularly reevaluated based on the latest clinical findings and the patient’s comfort and preferences.
(b) Flexibility in approach: While the initial decision might be to observe, it is essential to remain open to changing the course of action if the patient’s condition evolves or if potential risks start to outweigh the benefits.
Opting for a strategy of observation without immediate extraction for impacted canines is a viable route in specific clinical scenarios. However, it necessitates a comprehensive under- standing of the condition, clear communication with the patient or their guardians, and a commit- ment to regular monitoring. This approach allows for a balanced consideration of the patient’s cur- rent and future dental health, providing a foundation for informed and adaptive decision-making.
4 Forced Eruption of Impacted Teeth
1. Surgical exposure for forced eruption of impacted maxillary canine
(a) Incision: Typically, incisions such as sul- cular, vestibular, and mucogingival junc- tion incisions can be used, and the choice depends on the location of the impacted canine. In cases where the canine is pala- tally impacted, a palatal approach may be inevitable. The incision size should be about 1–2 cm, sufficient to expose the crown of the tooth (Fig. 5.2a).
(b) Flap elevation: A full-thickness flap ele- vation should be performed, followed by ensuring adequate hemostasis (Fig. 5.2b). 
(c) Bone grinding or removal of labial bone of canine crown: In most cases of impacted canines, the labial bone over the crown is either perforated or remains as a thin film. In such cases, bone curettes can be used to remove it, or if the remaining bone is thick, a drill may be utilized for removal (Fig. 5.2c, d).
(d) Bonding of orthodontic button: Before attaching the orthodontic button, it is cru- cial to ensure thorough hemostasis and use dry gauze to make the canine crown completely dry. After achieving a per- fectly dry state, an orthodontic resin bond is used to attach the orthodontic button (Fig. 5.2e). The placement of the button is critical for the application of orthodontic force, so its position should be carefully evaluated and selected. Generally, the button is attached to the labial surface of the canine. After the button is attached, a gold chain is connected and brought out into the oral cavity. The point where the chain is pulled out should be chosen based on what is most advantageous for applying force, either at the crestal inci- sion site or through attached mucosa. To minimize patient discomfort, the gold chain is temporarily fixed to the crown of an adjacent tooth.
(e) Hemostasis: Many patients experience swelling and bruising due to bleeding post-surgery. Adequate hemostasis is essential to prevent these complications.
(f) Closure: In children, absorbable 4-0 vic- ryl can be used for continuous suturing, eliminating the need for stitch removal. In adults, suturing can be done using silk or nylon (Fig. 5.2f).
2. Clinical case of forced eruption of bilaterally impacted maxillary canines
A 9-year and 4-month-old female patient presented with bilateral maxillary canine impaction. Following the surgical exposure of both impacted maxillary canines, a forced eruption procedure was performed (Fig. 5.3)
3. Clinical case of forced eruption of impacted mandibular canine
A 10-year and 2-month-old female patient presented with non-eruption of the left mandibular canine. Radiographic examina- tion revealed impaction of left mandibular canine (Fig. 5.4). Under local anesthesia, and tooth #33 was treated with forced eruption instead of extraction. After initiating the forced eruption of #33, orthodontic treatment was conducted to create space for teeth #33. Two years post-surgery, satisfactory occlusion was achieved.
4. Impacted maxillary canine and premolars— multiple surgical exposure clinical case
A 12-year and 7-month-old male patient presented with non-eruption of the left maxil- lary permanent teeth (Fig. 5.5). Radiographic examination revealed impaction of teeth #23, #24, and #25, with a dentigerous cyst observed above the crown of the impacted tooth #23. Cyst removal surgery was performed under general anesthesia, and tooth #23 was treated with forced eruption instead of extraction. After initiating the forced eruption of #23, orthodontic treatment was conducted to create space for teeth #24 and #25, followed by a stepwise forced eruption of these teeth. Five years post-surgery, there were no signs of cyst recurrence, and satisfactory occlusion was achieved.
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