CLINICAL CASES

Case 1: Laser-Assisted Crown Lengthening

A 23-year-old man presented with a chief complaint of an unsightly smile (Fig. 1A). Clinical examination revealed gingival erythema, hyperplastic and edematous swelling of gingival tissue, excessively covering the clinical crowns with asymmetry, and severely worn incisal edges (Fig. 1B). Radiographic examination was unremarkable. Medical history review revealed severe allergy problems, collapsed airway, and mouth breathing.


Fig 1A, Prepoerative view. Note uneven smile line

Fig 1B, Close-up view of smile line with asymmetry.

The diagnosis was (1) established gingivitis (unchanged for years without progressing to periodontitis) and (2) hyperplastic swelling of gingival tissue with asymmetry. Discolored composites and bruxism were noted as well. The treatment objective was to perform crown lengthening with osseous resection to establish the biologic width, using the argon laser, which absorbs hemoglobin, producing excellent hemostasis in biologic tissue.

By moving the fiber in and out of focus to change the power densities, different desirable tissue effects, such as cutting, vaporizing, coagulation, and tissue welding, can be carried out during the surgery. The treatment area was infiltrated with 2% lidocaine with 1:100,000 epinephrine. A gingival flap was raised by making small vertical incisions between the lateral incisors and cuspids with scalloped envelope cuts from lateral incisor to lateral incisor. Surgical round burs were used to create an ideal crescent of bone height on left central incisor (Fig. 1C). A 514.5-mm argon laser with a 300-µ fiber, along with water and air spray and high-speed evacuation, was used at 1.25 W of power with a pulse duration of 0.20 second, pulse interval of 0.10 second. The fiber was kept in contact with the tissue. Three interproximal sutures were placed to secure the flap. The laser fiber tip then was pulled back (out of focus) 2 mm for coagulation and 1 minute tissue welding. No dressing was placed (Fig. 1D). The patient experienced no postoperative discomfort, and neither analgesics nor antibiotics were prescribed. A postoperative visit was scheduled at 1 week (Fig. 1E) and 3 weeks (Fig. 1F). The upper four incisors were restored with porcelain veneers (Fig. 1G), and a night guard was fabricated. The patient was pleased with the results and benefited from the laser-assisted crown lengthening and restorative work, showing his confident smile (Fig. 1H).


Fig 1C, Flap surgery to correct osseous architecture.

Fig 1D, Immediate postoperative view of interproximal sutures with no dressing

Fig 1E, One week postoperative

Fig 1F, Three weeks postoperative

Fig 1G, Four unit porcelain veneers in place

Fig 1H, Improved smile line

Case 2: Gingivectomy and Gingivoplasty

A 17-year-old boy presented with hyperplastic gingival tissues (Fig. 2A) that could be consequential to his orthodontic treatment. (The author sees many adolescent orthodontic patients whose lack of discipline in the upkeep of oral hygiene has contributed to hyperplastic, edematous gingival tissue.) All diagnostics revealed healthy teeth and alveolar bone. There was no bleeding with probing and 3-mm average pocket depths. The treatment area was infiltrated with 2% lidocaine with 1:00,000 epinephrine. A 1064-nm free running pulsed Nd:YAG laser was used with a 300-µ fiber, set at 40 mJ, 80 Hz, 3.2 W, for a duration of 3 minutes. The fiber tip lightly contacted the tissue, scalloping and beveling the excessive tissue to the proper gingival architecture of a pleasing smile. A close-up look and comparison of the gingival tissue (Fig. 2B) and completed immediate postoperative view (Fig. 2C) presented a bloodless clean surgical site. There was no postoperative discomfort. Neither analgesics nor antibiotics were prescribed. At the 1-month postoperative visit, the patient presented with a healthy and pleasing smile. The close-up view presented complete healing and a pleasantly scalloped gingival outline (Fig. 2D).


Fig 2A, Preoperative view. Note hyperplastic gingival tissues.

Fig 2B, Close-up view. Comparison of gingival tissues.

Fig 2C, Immediate postoperative view.

Fig 2D, One month postoperative view. Note scalloped gingival line.

Case 3: Bleaching Combined With Veneers and Frenectomy

This is a multidisciplinary case, involving laser bleaching and laser curing with an argon laser. A maxillary labial frenectomy was performed with a free- running pulsed Nd:YAG laser. A 71-year-old woman presented with an aberrant and heavy frenum exerting excess pull on the gingival margin and the interdental papilla, resulting in localized recession (Fig. 3A). She was interested in acquiring porcelain veneers, fixing the black triangle (gingival embrasure of the upper central incisors), and whitening her teeth. Composite bonding was placed between the central incisors to close the diastema, but the gingival embrasure stayed as a black triangular area (Fig. 3B).


Fig 3A, Preopoerative view. Note discolored dentition with undesirable negative emrasure spaces.

Fig 3B, Preopoerative close-up view of discolored dentition, negative embrasure spaces, and heavy frenum.

The bonding was removed, and conservative preparations were completed on teeth 6 through 11 for porcelain veneers. The teeth then were bleached with three applications of Shofu Hi-Lite. This bleaching compound was activated using the argon laser at 350 mW for 20 seconds per tooth per application; the color of the teeth changed from shade A3.5 to Al (Fig. 3C). The heavy frenum (Fig. 3D) was anesthetized with an infiltration of 0.5 mL 2% lidocaine with 1:100,000 epinephrine. The frenum was stretched and cut using the Nd:YAG laser with a 300-µ fiber set at 80 mJ, 40 Hz, 3.2 W in a contact position (Fig. 3E). No intraoperative or postoperative discomfort was experienced. Neither analgesic nor antibiotic prescriptions were given. The assessment of postoperative visits at week 1 (Fig. 3F) and week 3 (Fig. 3G) showed excellent healing. The patient was pleased with the instant gratification the laser bleaching provided and happy with the porcelain veneers, which were seated with the help of an argon laser curing. The patient completed the surgical procedure with no pain and appreciated her new smile. She benefited greatly from this new technology (Fig. 3H).


Fig 3C, Immediate postoperative laser bleaching and preparation of upper anterior teeth for porcelain veneers.

Fig 3D, Close-up view of heavy frenum.

Fig 3E, Immediate postoperative view of frenectomy.

Fig 3F, One-week postoperative view of initial healing of frenectomy.

Fig 3G, Three-week postoperative view of complete healing of frenectomy.

Fig 3H, Smile benefit from laser bleaching, argon curing of veneer, and frenectomy.

SUMMARY

Dental lasers contribute significantly to the field of cosmetic dentistry, providing an invaluable resource for clinicians who perform different types of esthetic procedures. Practitioners in this specialized field not only help patients acquire beautiful and ideal smiles and dental health, but also they assist patients in benefiting from tremendous clinical advantages, such as sterile surgical sites and increased comfort levels. Tooth whitening will always be an important component of cosmetic dentistry. Developing the most efficient and safe method of tooth whitening is the goal of power bleaching. Currently the argon laser has proved to be the most valuable energy source for power bleaching. Clinicians need to learn more about constantly updated technology and apply newly discovered methods and protocols to clinical situations to benefit patients and clinicians.

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