Australasian Dentist Magazine Sept-Oct 2021

Category 58 Australasian Dentist b. Pre-Orthodontic gingival surgery Root coverage and Gingival recession: Alveolar bone dehiscence is a localized defect of the cortical bone which covers the teeth. When the denuded areas extend through the marginal bone, the defect is called as ‘dehiscence’, leading to development of gingival recession. If the patient shows a minimal zone of attached gingiva or thin tissue, a free gingival graft is used. It controls the inflammation and should be done before the initiation of orthodontic tooth movement. Gingival recession is more common in buccal orthodontic movements. In case for children or adolescents, if no orthodontic treatment is planned, areas of thin gingival tissues should be monitored only periodically as the width of the attached gingiva generally increases with normal growth from the mixed to the permanent dentition. As long as the tooth is moved within the envelope of the alveolar process, the risk of harmful side-effects on the marginal soft tissue is minimal. active orthodontic therapy i.e., a fewweeks before the removal of the orthodontic appliance, after overcorrection of the rotated tooth. Three-wall intra-bony defects: The bony support of the periodontium is lost resulting in deep pocket formation. Bone grafts using either autogenous bone from the surgical site or allografts, along with resorbable or non-resorbable membranes in filling of these three-wall defects. Orthodontic treatment may be initiated if the result of periodontal therapy is stable 3-6 months after surgery. clinical Figure 5 Osseous defect eliminated by reshaping and reducing the pocket depth Furcation defects: Furcation involve­ ment is a condition in which bifurcation and trifurcations of multi-rooted teeth are invaded by periodontal disease. They are difficult to maintain and can worsen during orthodontic treatment. In Class III furcation cases, a possible method for treating the furcation is by hemisecting the crown and root and pushing the roots apart. If the hemi-sectioned teeth are planned to be used as abutments for a bridge, moving the roots apart orthodontically permit favourable restoration. Figure 6 Three wall osseous defects corrected with freeze dried bone used for regenerating defects Figure 7a Molar with furcation involvement Figure 7b Correction of Furcation defect with hemisection of tooth and root distalisation Crown lengthening: Done in teeth with shorter clinical crown to facilitate proper placement of orthodontic appliance. Crown lengthening should be done using ‘gingivectomy’ prior to orthodontic bonding procedures. In case of shorter clinical crowns in the mandibular arch, apically repositioned flap in combination with gingivectomy can be done for crown lengthening, thereby increases the width of the attached gingiva providing better results. 4. Periodontal procedures during orthodontic treatment Fiberotomy- Orthodontic toothmovement results in reorganization of collagenous fibres, elastic fibres, and the periodontal ligament to accommodate the new tooth positions. In order to prevent relapse and to achieve proper rearrangement of the supporting tissues, the teeth must be retained. Circumferential supracrestal fiberotomy (CSF) is done to correct the relapse of severely rotated teeth that occurs due to rebound of elastic fibres in the supracrestal tissues. Fiberotomy is usually performed toward the end of the Labial augmentation bone grafting to modify the alveolar bone width and cover the dehiscence Figure 8 Pre orthodontic bone augmentation Frenotomy/Frenectomy: Abnormal frenum attachment results when a v-shaped bony cleft is formed between the two central incisors and a thick frenum resists orthodontic forces and is responsible for the relapse of space closure especially in cases with midline diastema. The mandibular frenum is associated with a decreased vestibular depth and an inadequate width of the attached gingiva. The frenum is incised and the triangular resected portion of the frenum is removed. Frenectomy is more commonly performed procedure; however, the undesirable loss of interdental papilla is a major complication. Hence, the frenotomy which represents only a partial removal of frenum with the purpose of relocating the attachment in an apical direction is aesthetically preferred. Figure 9 Fiberotomy Gingivectomy/Gingivoplasty: The gingival margin level of the six maxillary anterior teeth plays an important role in the aesthetic appearance of the crowns. Discrepancies in the gingival margin level may be due to ectopic eruption of the tooth or due to altered position of the gingiva. A proper solution is to assess the gingival margins of maxillary central incisors and the lip line when the patient smiles. Gingivectomy is a simple surgical procedure to excise the enlarged gingiva in order to eliminate suprabony pockets if the pocket wall is fibrous and firm and to remove gingival enlargements post- orthodontic treatment. Gingivoplasty is surgical recontouring the gingiva in the absence of pockets in order to achieve a physiologic contour. In this procedure, the reshaping of attached gingiva is done to provide more aesthetic and functional contours. Cortectomy-assisted Orthodontic Treatment (CAOT): This method has been employed to accelerate orthodontic Figure 10 Frenectomy