Immediate Bone Augmentation After Infected Tooth Extraction Using Titanium Membranes

Immediate implant placement after tooth extraction may result in early implant failure caused by insufficient mature bone mass and quality1 to adequately support the implant, and difficulty in obtaining complete coverage of the extraction socket by soft tissue. Even if primary closure is accomplished, early membrane exposure by epithelial dehiscence can occur. This may cause membrane exposure and infection, which can jeopardize bone augmentation2,^–3 and ultimately may result in implant failure.4 Placement of the implant immediately after tooth extraction reduces costs, surgical procedures, and time to rehabilitation while preserving papillae and soft-tissue scalloping. Appropriately selected immediate implant cases have reported short-term (1–2.5 years) success rates approximately equal to 90%.5 However, there is a higher (threefold) incidence of early membrane exposure6 and infections when compared to early implant placement (after 8 weeks), especially when immediate bone augmentation (IBA) was simultaneously performed with implant placement.7 Jovanovic8 suggested that immediate implants require sufficient bone wall around the extraction socket and apical to the bottom of the extraction socket for primary stability, and an absence of lesion in the extraction socket. Sufficient soft tissue for wound closure is also required.

The decision whether to perform immediate9,^–10 or delayed guided bone regeneration (GBR) and implant placement11 is subject to considerable debate. Some clinicians suggest that simultaneous GBR and implant placement can be performed 2 months after tooth extraction with membrane removal 6 months later.12 If the condition of the alveolar ridge is poor, immediate GBR and delayed implant placement may be the preferred option, but this has not been supported by a randomized clinical trial.13 IBA prevents the additional bone resorption that typically occurs in the initial 6 months post extraction and abbreviates the rehabilitation period. Unfortunately, a higher failure rate caused by early membrane exposure1 with subsequent infection remains a concern.

Since it is difficult to define the acuity, severity, and histology of the bone-destructive process responsible for both tooth loss and bone deficit, it is cumbersome to conduct a randomized clinical trial to define the best strategy. In the absence of randomized clinical trials, the optimal time for GBR in reference to the tooth extraction and implant fixation is controversial and should be individualized based on patient and lesion characteristics.

The absolute contraindications to IBA are not well defined. Patients with such pathologies as vertical fracture with infected sinus tract, extensive periodontal disease or external resorption, and severe periapical or periradicular process, are not considered ideal candidates for either IBA or immediate implant placement.

Contraindications for immediate implant placement include extensive deficient alveolar bone, close proximity to the mandibular canal and maxillary sinus, inability to achieve primary closure of the surgical incision, and extensive periapical or gingival inflammatory process.14 Unfortunately, complications requiring unplanned additional surgical procedures may approach 50%15 in high-risk groups.

This report documents 15 consecutive cases of immediate bone augmentation in a subset of high-risk patients using a titanium membrane.

Study participants were candidates for tooth extraction because of an extensive inflammatory process including one or more of the following pathologies: vertical fracture with infected sinus tract, extensive periodontal disease or alveolar ridge resorption, and/or severe periapical or periradicular process. All patients received an explanation regarding the procedure and signed an informed consent.

• a) Silk sutures 3/0, polypropylene Nylon 5/0 sutures (CliniSut, Sasurel, Middlesex, UK)

• b) Titanium membrane (Hi-Tec Implants Herzlia, Israel)

• c) Autologous fibrin obtained by centrifugation of 40 mL autologous blood divided into 4 test tubes and spinned for 10 minutes at 2700 rpm by FiberTec centrifuge.

• d) Synthetic bone graft (Bi-Ostetic, Berkeley Advanced Biomaterials Inc, San Leandro, Calif).

A preprocedural nonsteroidal anti-inflammatory agent (Celexicob, 200 mg daily) and amoxicillin and clavulanate potassium (Augmentin 875, Smithkline Beecham Healthcare Ltd, Brentford, UK) administered twice daily, were initiated 24 hours prior to the procedure. Nitric oxide gas was administered, and local anesthesia (infiltration of buccal and palatinal region in upper jaw, and inferior mandibular and long buccal block in the lower jaw) was accomplished by articain 4% (Ubistesin forte, 3M ESPE AG, Seefeld, Germany). An intrasulcular flap-releasing incision was made around the tooth to be extracted and extended to 2 adjacent teeth while carefully maintaining the papillae ("envelope flap").

Atraumatic tooth extraction was performed according to conventional standards and was followed by meticulous curettage of the infected and granulated tissue in the socket (Figure 1a). The defect size was measured with a periodontal probe, and the titanium membrane was trimmed ≥2 mm from each direction of the measurements obtained. It was then applied to the socket walls (Figure 1b) and the socket was filled (Figure 1c) with autologous platelet-rich fibrin (PRF). Primary closure was achieved by using 3/0 interrupted and horizontal sutures (Figure 1d). In case of tension, 2 vertical incisions and a coronally positioned flap were performed. Simple interrupted 5/0 sutures were applied to the vertical incision. The patient was instructed to rinse the mouth with chlorhexidine 0.2% twice daily, continue antibiotic therapy for 7 days, and not to wear any prosthesis, chew or brush on the affected area for at least 2 weeks. Seven days after surgery the patient was reappointed for wound inspection and suture removal (Figure 1e). Eight weeks later, membrane removal and implant placement were performed (Figure 1f).

Tables 1 and 2 summarize the results of immediate bone augmentation employing titanium membranes (Figures 2a through 3d). Patients ranged in age between 28 and 63 years (mean age was 38). Eight patients (53%) were female and 7 (47%) were male. Seven patients (47%) experienced early membrane exposure (between weeks 2 and 6), which was treated conservatively by plaque control and oral hygiene. There were no infections warranting early membrane removal. In all patients, sufficient bone augmentation was documented and 8 patients were subsequently treated with implants without any additional guided bone regeneration.

In this study early bone augmentation after extraction of infected teeth and extensive bone loss was executed safely using a titanium barrier membrane accompanied by socket filling with PRF or occasionally with synthetic bone graft material. Although early membrane exposure occurred in 47% of these patients, it was not associated with any apparent infection or problem, and did not jeopardize bone augmentation. Some of these patients underwent uneventful implant placement 10 to 18 weeks after the initial surgical procedure. Whether the membrane material affected the quality and extent of GBR could not be determined by the present study. Some researchers suggested that polytetrafluoroethylene (PTFE) membranes are superior to resorbable membranes (human study),16 or titanium membranes (limited dog study),17 while other investigators found collagen membranes to be as effective as PTFE membranes.18 

Based on previous reports employing titanium foil19 or micromesh, either alone20 or in conjunction with PTFE membrane,21 and the limited results of the present study, we believe that the titanium membranes serve as an excellent barrier membrane for GBR. Large-scale randomized clinical trials need to confirm these initial encouraging observations and to determine if titanium membranes are less susceptible to infection than PTFE membranes. Whether any additional bone augmentation material adds to IBA is also an open question as some canine models suggest that no filing material enhances implant osseointegration.22 

Immediate bone augmentation after infected tooth extraction employing titanium membrane, PRF, and occasional synthetic bone graft material, yielded adequate bone fill to support implant placement at approximately 8 weeks. Further studies need to investigate whether titanium membranes are more resistant to plaque accumulation and infection than other membrane materials subjected to early membrane exposure.

The authors of this manuscript have no financial association that might pose a conflict of interest in connection with the submitted proposal.