Written by Dr. Bana Al Haydar, DDS, MS

Providing patients with an optimal esthetic result is an essential part of contemporary dental practice. An excessive gingival display can have a negative impact on a patient’s smile. Excessive gingival display due to gingival enlargement, altered passive eruption or non-optimal crown proportion can be effectively corrected by periodontal surgery.

Materials and Methods

Clinical Presentation

A 62-year old male was referred to the Postgraduate Periodontal clinic to evaluate maxillary anterior teeth for esthetic crown lengthening surgery in anticipation of placing partial labial veneers (PLV) on the six anterior teeth. Periodontal evaluation indicated probing depths of 3-4mm, adequate plaque control, no mobility, adequate amount of attached keratinized tissue, thin gingival phenotype and a high smile line. A multidisciplinary diagnosis determined that periodontal esthetic crown lengthening surgery with osseous resection was required.

Diagnosis

The Chu’s gauges (Chu’s Proportion Gauge, Hu-Friedy Mfg. Co., LLC, Chicago, IL) was used to evaluate teeth in the maxillary esthetic zone. The optimal incisal edge position was established by means of phonetics and esthetic evaluation, in anticipation of the definitive restoration with desired tooth proportions. CEJ of the central incisors were 1mm subgingival. Bone sounding of the radicular and proximal dentogingival complex (DGC) was performed to determine the supracrestal attachment of each tooth.

Figure 1. A, initial presentation frontal view; B, initial presentation palatal view; C, D, tooth proportion measurement with Chu’s gauge; E, bone sounding; F, proposed free gingival margin and corresponding osseous crest level.

Guide Fabrication

A maxillary cast with proposed free gingival margin (FGM) was optically scanned utilizing a desktop scanner (Planmeca Planscan® Lab, Planmeca, Helsinki, Finland). Surgical guide was designed with an open-source 3D computer graphics software toolset (Blender, Blender Foundation, GPLv2+).

The surgical guide consisted of two key components;

the position of the proposed free gingival margin
the position of the correlating osseous crest level

Figure 2. 3D printed surgical guide with proposed free gingival margin and correlating osseous crest level.

Surgical Intervention

An inverted beveled incision was made based on the surgical template at the projected position of the proposed free gingival margin (FGM). This position revealed the anatomic crown of the tooth. The facial aspect of the papillae were dissected leaving the interproximal tissue in place. A full thickness mucoperiosteal flap was reflected exposing the underlying alveolus. Based on the supracrestal attachment of the individual teeth and the proposed FGM, osteoplasty was performed exposing 2.5mm of the tooth surfaces. The flap was closed with 4-0 chromic sutures. The patient was prescribed ibuprofen 600mg PRN and chlorhexidine 0.12% rinse bid for 14 days.

Figure 3. Surgical guide adaptation evaluated prior to surgery. Adequate seating was verified with inspection windows.

Figure 4. A, zenith of the proposed FGM marked; B, surgical guide utilized for initial incision; C, inverted beveled incision reinforced; D, full thickness mucoperiosteal flap elevation; E, osteoplasty performed according to proposed FGM and supracrestal attachment measurements.

Figure 5. A, surgical guide adapted to evaluate osseous crest level; B, surgical guide adapted to evaluate soft tissue level; C, immediate post-operation frontal view; D, immediate post-operation incisal view; E, tooth proportion evaluated utilizing Chu’s gauge.

Figure 6. A, 2-weeks post-operation frontal view; B, 5-weeks post-operation frontal view; C, 6-months post-operation frontal view; D, pre-operation frontal view; E, 6-months post-operation frontal view.

Figure 7. A, 6-months post-operation probing; B, 6-months post-operation bone sounding.

Results

Uneventful healing was observed at 2- and 5-weeks post operatively. The 6-months follow-up exhibited a stable gingival margin and improved dental and facial esthetic outcome. Definitive restoration was postponed as probing and bone sounding indicated supracrestal attachment was not sufficiently re-established.

Conclusion

This case exemplifies a multifaceted approach of biologic principles of supracrestal attachment dimensions and wound healing, with contemporary digital dentistry utilizing a prosthetically driven esthetic crown lengthening surgery using a 3-D printed surgical guide.

Written by Dr. Bana Al Haydar, DDS, MS