Microprecision

Piezosurgery cuts mineralized tissues with microprecision. The cut is made by mechanical microvibrations at a linear range of approximately 80 µm and a frequency of 30,000 times a second. A sound wave is overmodulated on this base frequency, which generates a hammering action with very little heat because the mechanical energy necessary to produce the microvibrations is very low. This action, along with the water spray, facilitates removal of bone debris.

Piezoelectric osteotomies are easy to create, but it is important to recognize that the technique and instrument handling are different than the technique using a traditional handpiece with rotary instruments. The piezosurgery insert is applied to the bone with a relatively light stroke similar to the smooth precision used to draw a picture. Heavy pressure or force is not required. Indeed, the pressure applied by the surgeon to the piezosurgery handpiece is much lower than the pressure typically applied to a rotary or oscillating type handpiece, which uses mechanical macrovibrations for cutting. This characteristic provides maximum control during surgery and makes this technique unique especially in areas with delicate anatomy.

Selective Cutting

Piezosurgery ultrasonic microvibrations are low frequency and selective for cutting mineralized tissue only. These microvibrations are physically unable to cut soft tissue. Clearly, the most significant demonstrated benefit of piezosurgery selective cutting is the ability to preserve the integrity of soft tissues, such as the alveolar nerve, the infraorbital nerve, the maxillary sinus membrane, and the dura mater, while effectively cutting the mineralized tissue (bone) in close proximity to these tissues.

Maximum Visibility

Piezosurgery creates a surgical field that is blood free during cutting because of its cavitation effect. Cavitation is a physical phenomenon that, from a clinical standpoint, happens with the nebulization of the saline solution. The slight hydropneumatic pressure applied by piezosurgery temporarily stops bleeding from both hard and soft tissues. It is important for the liquid pump to be flowing properly and for the cutting action to be intermittent to maintain optimal surface microcirculation, especially for long surgical procedures. Tissue perfusion resumes shortly after cutting (and cavitation action) is stopped.

Excellent Healing

Clinical studies comparing use of piezoelectric bone surgery with traditional rotary instruments for third molar extractions¹⁴ and periodontal surgery²⁵ have reported better recovery and fewer postoperative symptoms in those treated with piezosurgery. Postoperative healing after piezoelectric bone surgery is characterized by minimal swelling and little bleeding and postoperative morbidity is lower compared to traditional techniques.²⁴ Gingival tissue is typically light in color when compared to the appearance of autogenous gel of platelet-rich plasma.

Periodontal Surgery

The use of piezosurgery in periodontal surgery simplifies and improves handling of soft and hard tissues.³⁰ In resective periodontal surgery, for example, after raising the primary flap with a traditional technique, using a scaler-shaped insert (PS2) (Figure 80-3, A) or an insert in the shape of a rounded scalpel (OP3) makes it easier to detach the secondary flap and remove inflammatory granulation tissue. This phase has little bleeding as the result of the cavitation of the saline solution (coolant). With the right inserts and power mode, the ultrasound device facilitates effective scaling, debridement, and root planing (Figure 80-3, B and C). In particular, debridement with a special diamond-coated insert enables thorough cleaning even for interproximal bone defects (Figure 80-3, D). The mechanical action of ultrasonic microvibrations, together with cavitation of the irrigation fluid (pH neutral; isotonic saline solution) eliminates bacteria, toxins, dead cells, and debris, which creates a clean physiology for healing. Healing is improved by applying ultrasound to produce micropits at the base of the defect to activate cellular response of healing mechanisms. Autogenous bone-grafting material consists of bone chips that are collected during the piezoelectric osteoplasty operation for recontouring bone irregularities (Figure 80-3, E). The result is that this technology reduces the invasiveness of traditional surgery by making surgery faster and by ensuring thorough cleaning of the periodontium. It also favors tissue healing by using bone removed in the osteoplasty procedure to graft osseous defects.

Piezosurgery in periodontal surgery redefines the guidelines that mark the border between resective treatment and regenerative treatment. Indeed, the choice between a resective technique and a regenerative technique generally depends on the depth of the bone defect, whether it is higher or lower than 3.5 mm.

The ability to work on the bone defect with magnifying systems makes it possible to exploit the benefits of piezosurgery microprecision in preparing the recipient site and stabilizing micrografts (Figure 80-3, F to H).

Crown Lengthening

Clinical crown lengthening is the most common periodontal surgical (ostectomy) operation performed in otherwise healthy periodontal conditions. The indication for this procedure is usually associated with a need or desire to expose more tooth structure because of short clinical crowns and/or loss of clinical tooth structure. In general, the goal is to reposition the periodontal bone and soft tissues to a more apical position with appropriate biologic dimensions and minimal periodontal inflammation.

The clinical crown lengthening technique entails performing a periradicular ostectomy of a few millimeters, which allows repositioning of the periodontal flap in a more apical position. The positive result obtained is that the health of the treated part is preserved even though the normal gingival morphology is altered. Clinical application must include esthetic assessment, as well as an assessment on the position and health of the adjacent periodontium.

The traditional surgical technique entails raising a full-thickness flap, performing the ostectomy with manual instruments, osteoplasty with a bur for crest bone architecture recontouring, periradicular bone removal, root planing, and, finally, replacing the flap in an apical position.

The ostectomy is simple to perform using piezosurgery in direct contact with the root surface because control of the instrument during surgery is precise, even in very difficult proximity cases (piezosurgery OP3 insert). The root planing phase can be performed very effectively using blunt ultrasonic inserts (piezosurgery PP1 insert).

Saline solution cavitation reduces bleeding during surgery and facilitates debridement of the surgical area. This effect is likely responsible for the excellent soft-tissue healing result, which is always />