Despite being considered of more esthetic than of functional concerns, it has been demonstrated that an excessive gingival display (or gummy smile) may have a detrimental impact on the opinion of “a patient’s attractiveness, friendliness, trustworthiness, intelligence, and self-confidence” [14].

Descriptions of the use and outcomes of clinical lengthening procedures for the correction of anatomical discrepancies of the gingival and osseous architectures (e.g., altered dental eruption), gummy smile, and prior to prosthetic restorations may be found in the literature, and these approaches have encompassed the use of periodontal surgical techniques alone or in association to restorative procedures:

Treatment of patients with high smile line (gummy smile) or with discrepancies in the gingival margin (zenith) of anterior teeth that may impact the patient’s esthetics (i.e., patient’s personal report describing a deteriorated esthetic appearance due to its “gingival smile”)

Exposure of no more than 2 mm of gingival tissue during a natural smile (i.e., medium or low smile line) and in areas where the stability of the dentition may be compromised

For the flapless esthetic clinical crown lengthening procedure [12], an adequate band of keratinized tissue and a thin bone should be present. In this procedure, sulcular or inverted beveled incisions are performed on the anterior teeth requiring crown lengthening based on the amount of bone/soft tissue to be removed and the new position of the gingival margin established (in relation to the cementoenamel junction). This may be facilitated with the assistance of a diagnostic wax-up, a clinical mock-up, and an acrylic individual surgical guide since it assists the picturing of the future position of gingival margins and restorations’ shape (when indicated). These steps permit a more accurate, predictable, and less traumatic/invasive surgical procedure. After that, the collars of gingiva should be removed, and osseous remodeling takes place via “gingival sulcus” using micro-chisels, and no suture procedures are required (Fig. 5.3).

With respect to the conventional surgical procedure, full-thickness flap rising should be performed after the removal of soft tissue collar. Osseous resection may be carried out using chisels or rotatory instruments with carbide burs, and the flap is positioned at the level or apical to cementoenamel junction (based on the periodontal/restorative treatment proposed) and sutured by 5-0 or 6-0 nylon/Teflon sutures (Fig. 5.4). The sutures are removed 14 days after surgery. In addition, patients should be instructed not to brush the teeth in the treated area, as well as they are prescribed 0.12 % chlorhexidine gluconate and instructed to rinse gently twice a day for 2–3 weeks, or until safe and comfortable toothbrushing can be performed. Overall, like all other periodontal plastic surgery procedures, analgesics, anti-inflammatory drugs, and/or systemic antibiotics are prescribed if needed, as well as no adverse effects are expected in the treated sites.

Orthodontic extrusion associated with periodontal flap surgery or fiberotomy, during or immediately after extrusion, may be considered an additional resource for single tooth requiring esthetical clinical crown lengthening [20]. Fiberotomy has the advantage of preventing the return of the dental structure to its original position or the concomitant extrusion of both soft and hard tissues, which may lead to the need of additional plastic periodontal surgical procedures [20]. However, in sites lacking interpapillary gingiva, orthodontic extrusion without fiberotomy may provide superior esthetical gains (Figs. 5.5 and 5.6).

Most of the data on crown lengthening procedures regard to studies on teeth requiring restorative approaches. Indeed, just one randomized trial on the treatment of anterior teeth exclusively due to esthetical purposes (on multiple teeth) was published up to now [13]. Overall, the outcomes accomplished by the use of esthetical clinical crown lengthening procedures, in clinical terms, may improve patients’ esthetics because of the harmonization of the gingival tissues and teeth and the concomitant improved balance between lips, gingiva, and facial profiles [13]. These favorable conditions will result in more stable outcomes that may be maintained for long-term periods when the patients’ full-mouth plaque score is less than 20 % [16].

The use of flapless approaches may decrease gingival height and volume, as well as lead to a minimal injury to the blood vessels and tissues, a reduced surgical morbidity, a more uniform healing process, and prevent the formation of scars [12, 13, 16]. Additionally, multidisciplinary treatment plans based on a diagnostic wax-up and a mock-up may guide the surgical procedure, reduce the gingival trauma, and assist posterior prosthetic treatment planning with restorative/prosthetic laminate veneers or full crowns. For such cases, the locations of the future biological width should be anticipated. However, information on the long-term maintenance of results have not been established yet, thus the potential of tissue regrowth (specially within patients presenting a thick periodontal biotype) should be assessed during wound healing in order to establish the best time for the subsequent definitive restorative treatment when intrasulcular prosthetic margins are planned to complete the case [9, 11].

Additionally, when multidisciplinary approaches were indicated for teeth presenting color alterations, shape deformities, irregular positioning in the dental arch, inadequate contact points, cervical lesions, and excessive occlusal wear, these should be carefully planned. The establishment of a proper crown length/width ratio may improve the outcomes of surgical procedure (i.e., central incisors > canines > lateral incisors) as it may provide an improved balance between teeth and gingiva during a smile (a better distribution of the six teeth of the anterior maxillary sextant) [7]. Within treatment planning involving ceramic crowns or laminated veneers, these should present smooth and precise margins located no more than 0.5 mm into the gingival sulcus, as well as a minimum of 3 mm distance of the margins of the restorations to the alveolar bone crest should be respected to prevent gingival inflammation and periodontal attachment loss [22, 23]. Provisional dental preparations and restorations (for porcelain veneers or full crowns) may be performed approximately 30 days after surgery, whereas definitive prosthetic restorations may be fabricated after full healing of periodontal tissue (i.e., 6 months postsurgery) [6]. As a general rule, the stability of the soft tissues surrounding ceramic crowns or laminated veneers will be directly linked to the health of periodontal tissues (e.g., lack of plaque-induced periodontal diseases), to the minimum trauma during intrasulcular margin placement and gingival displacement procedures, to the quality of provisional restorations, to the complete removal of excess of temporary and final cements, and the wait for the proper follow-up healing period after surgery before installing the definitive restorations [22].

Finally, the orthodontic extrusion may improve the esthetic crown lengthening as well. It should be performed based on clinical and radiographic data obtained at initial examinations, as well as it should be kept in mind that these may not provide an exact measurement of the amount of tooth/root to be extruded. When orthodontic extrusion was associated to circumferential fiberotomy, it does not lead to significant changes in the gingival and osseous tissues’ anatomy. Conversely, conventional orthodontic extrusion (without fiberotomy) may improve the amount of soft tissue in interproximal areas and favor the achievement of better gingival contours when associated to crown lengthening surgery (Figs. 5.7, 5.8, 5.9, 5.10, 5.11, 5.12, 5.13, and 5.14).