Discussion

The management of an anterior deep bite requires adequate treatment planning, especially if the clinical condition is associated with posterior DVO (vertical occlusion dimension) reduction due to multiple missing teeth. A multidisciplinary planning approach, including orthodontics, oral and periodontic surgery, and restorative dentistry, has an important role in the final outcome of treatment.

In this case, before orthodontic alignment, we decided to intrude elements 16 and 17 (supraeruption and rotation) with a local corticotomy associated with intrusive orthodontic movement. The feasibility of this minimally invasive surgery is strictly linked to the use of a piezo surgery device to perform latero-posterior segmental maxillary osteotomy. Ultrasonic bone-cutting surgery has recently been introduced as a feasible alternative to the conventional tools of cranio-maxillo-facial surgery, due to its technical characteristics of precision and safety.

In fact, it is possible to perform a linear, clean, and thin osteotomic bone cut with maintenance of the integrity of the vascular network. This particular aspect avoids damage of the palatal mucosa and spares use of the chisel to complete the corticotomy. Many studies indicate that conventional cutting tools can produce impairment of pulp blood flow and loss of tooth vitality. Furthermore, vascular compromise can occur due to direct or heat-induced injury to the soft tissue pedicles. To prevent such complications, we support the use of piezoelectric surgery in this critical multipiece surgery, as reported in the literature.

In these anatomically difficult conditions, a piezo surgery device provides good intraoperative visibility and a safe and precise osteotomy due to its micrometric characteristics and selective cut.

The piezo device offers many versatile inserts; inserts for implant site preparation appear to be particularly useful and versatile. We believe that the piezo surgery device offers many intra- and postoperative advantages and provides desirable clinical outcomes such as a favorable implant success rate, as reported in the literature.

In a multidisciplinary treatment approach, a multi-use specific tool such as a piezo device allows simplification of each surgical step within very difficult and complex management planning. In fact, it is possible to reduce intra- and postoperative complications (damage to soft tissues such as nerves, the blood vessel network, and dental pulp), to assist and accelerate intrusive and tipping orthodontic movement of migrated teeth, and to perform safe oral surgery.

Moreover, intrusion can be a reliable therapeutic treatment in patients with a healthy periodontal status because it does not result in a decrease of marginal bone level.

The best results are obtained when tooth intrusion is performed with light forces (5–15 g) and the line of action of the force passes close to the center of resistance. However, in our clinical report, after corticotomy surgery, tooth intrusion was performed with very high forces (>250 g) to mobilize the bone block, but the final clinical outcomes and periodontal status were satisfactory anyway. In this case, forces did not act on the tooth ligament but on the corticotomized bone: if forces were long-term and intensive on the ligament, hypoxia, root resorption, and vascular damage might occur.