Periodontal disease is a chronic inflammation caused by bacterial infection. This disease affects the structures that support the teeth. Besides clinical signs of disease and inflammation (i.e. red and bleeding gums) there are other specific structural changes that most of affected individuals cannot identify.
The most important change that this disease determines is bone loss. This process can be very rapid in progression or it may take years to manifest. Only radiographs and clinical measurements (gingival pocket measurement) are able to determine the extent of this destruction. For this reason, it is paramount to have regular check-ups with the dentist or periodontist that is specifically trained to prevent and treat periodontitis.
Depending on the extent and the depth of bone loss, there are some techniques available to arrest or decrease the missing structures that already occurred. One of these procedures is called Guided Tissue Regeneration (GTR). As the name describes, the goal of this therapy is to regenerate the tissues that are missing by guiding them with specific materials and devices with a minimally invasive surgical procedure. According to the type of bone defect, different materials can be employed.
In larger defects, a bone grafting material can be employed to fill the space that is missing and that was previously occupied by native bone. These grafts may have different origins; some derive from animals, some from human donors and others are synthetic materials. They differ in terms of properties, duration of action and clinical indications. Some of those materials will resorb and replaced by the patient’s own bone while others will stay in place for an extended period of time. In some cases a clinician may employ a membrane in order to guide the healing of tissues. A membrane can be made of non-resorbable or self-resorbable biocompatible materials. As for bone grafts, every case has its own features with different indications for one or the other kind of membrane.
Biologic molecules that enhance the healing and the proliferation of the cells expected for regeneration represent the third class of material often employed. They come into gels and solutions that are applied on the area of regeneration during periodontal surgery.
The rationale of using one of these regenerative procedures is to improve the prognosis (survival) of teeth that lost some different degrees of attachment and avoid or delay their extraction. Even though dental implants are routinely used to replace failing teeth, regenerative procedures may help to retain teeth and avoid multiple surgeries and time for implant placement. The ultimate goal of periodontal treatment is to treat diseased supporting teeth and only in case of untreatable disease, replace missing teeth with implants.
We report two clinical cases where GTR procedure was employed to replace part of the bone that was lost. The first subject is a 41yo male affected by localized angular deep bone loss with deep pockets on the posterior teeth. After a phase of professional hygiene to remove the etiologic factors that led to tissue destruction (dental plaque and calculus), GTR procedures were performed. Radiographic bone deposition can be seen in figure sequence.
Figure 1. A and B. Before and after GTR procedure. It is noticeable the disappearance of the “V-Shaped” bone loss on the first right molar. C and D. Before and after bone filling on the 2nd left premolar.
In the second case, a patient presented with severe bone loss and isolated pocketing on the mandibular incisors. Teeth extraction would have ended in a complex reconstruction to allow proper implant placement and not predictable esthetic result.
Figure 1. Deep pocket from the facial (a) and lingual aspect (b) of right lateral incisor.
Figure 2. a and b, above. Radiolucency showing bone loss at the level of lateral incisor and canine.
Figure c and d. Bone fill after GTR.
-By Lorenzo Mordini DDS, MS