When a tooth requires removal, a simple extraction using forceps may not be possible due to complexity below the gum line. Surgical extractions are necessary when the tooth is firmly anchored, broken, or improperly positioned within the jawbone. To remove the tooth with minimal force and trauma, the surgeon often divides it into smaller, manageable pieces. This controlled division, known as sectioning or odontosection, requires specialized instruments to precisely cut through the dense tooth structure, making the extraction safer and more predictable.
The Surgical Instrument Used for Sectioning
The primary instrument engineered for cutting or splitting a tooth is the high-speed surgical dental handpiece paired with a surgical bur. This specialized device is functionally similar to a traditional dental drill but is designed for the surgical environment. The handpiece operates at extremely high rotational speeds, often reaching 400,000 revolutions per minute, allowing for rapid, controlled cutting through enamel and dentin.
The handpiece holds the surgical bur, the actual cutting tool, typically made of tungsten carbide or diamond grit. Carbide burs, such as crosscut fissure burs, are commonly used for sectioning due to their efficient cutting action on hard tissue. These burs have an extended shank compared to general restorative burs, which is necessary for reaching deep surgical sites like impacted wisdom teeth.
This system provides a smooth, continuous, and highly controlled cut, minimizing the risk of inadvertently fracturing the jawbone or damaging adjacent structures. Modern surgical handpieces are also designed to be sterilizable and often feature fiber-optic lighting to improve the surgeon’s visibility. The combination of high speed and specific bur geometry makes this instrument the standard for atraumatic tooth sectioning.
Clinical Reasons for Splitting a Tooth
The need to section a tooth arises from anatomical challenges that prevent whole-tooth removal. One common reason is the extraction of multi-rooted teeth, such as molars, which have diverging roots anchored in the jaw. Dividing the tooth along the plane of the roots creates individual, single-rooted segments that are much easier to remove without excessive force.
Another frequent indication for sectioning is impaction, particularly with wisdom teeth, which are often trapped below the gum line or bone. An impacted tooth may be tilted, rotated, or obstructed by the jawbone. Splitting the tooth into smaller pieces allows for a path of withdrawal that minimizes the removal of supportive bone. This technique is also helpful when roots are ankylosed, meaning they have fused directly to the surrounding jawbone.
The decision to section a tooth is driven by the goal of preserving the delicate surrounding bone structure. Excessive force can fracture the thin bone plate, which is detrimental to healing and future implant placement. By converting a complex object into smaller segments, the procedure becomes less invasive, reducing postoperative swelling and accelerating recovery.
How the Sectioning Procedure Works
The sectioning procedure begins after the area has been completely numbed with local anesthesia and, in many cases, a small soft tissue flap has been gently reflected to expose the entire tooth structure. The surgeon then uses the high-speed handpiece, fitted with a surgical fissure bur, to make a precise cut through the tooth. For a mandibular molar, the cut is typically made centrally through the crown, extending down to the furcation, which is the area where the roots separate.
A constant flow of sterile water or saline solution is directed onto the bur and the tooth throughout the entire cutting process. This continuous irrigation serves the dual purpose of cooling the bur to prevent excessive heat generation, which could cause thermal damage to the jawbone and delay healing. It also flushes away tooth debris, allowing the surgeon to maintain clear visibility of the precise cutting line.
The surgeon must ensure the cut goes completely through the crown and into the root structure, dividing the tooth into separate segments. Once the tooth has been successfully sectioned, specialized instruments called dental elevators are used to gently wedge into the created space. These instruments apply controlled, deliberate pressure to mobilize each fragment individually, lifting it out of the socket.
The separated pieces are removed one by one, requiring minimal force and protecting the integrity of the bone. Finally, the socket is thoroughly cleaned and irrigated to ensure no small fragments or debris remain before the surgical site is closed with sutures.