A Technique for Atraumatic Extraction of Teeth Before Immediate Implant Placement Using Implant Drills

Abstract

Purpose: 

The purpose of this article is to present a minimally invasive technique using the implant drills to help extract teeth before the insertion of immediate implants.

Materials and Methods: 

Nine patients (7 women and 2 men) aged 24 to 60 years having root fractures and dental caries were included in this study. Inclusion criteria for the study were presence of at least 4 mm of bone beyond the root apex, the absence of acute signs of infection or inflammation in the treatment area, and the absence of systemic pathologies that would contraindicate bone healing around implants. Heavy smokers were not included in the study. Extraction was done after thinning the root walls by the help of the implant drills. After extraction, implant sites were prepared and implants were inserted. In 2 of the cases, the peri-implant bone defect was filled with autogenous bone graft.

Results: 

Healing progressed uneventfully in all 9 cases. The use of implant drills to thin the root walls provided atraumatic tooth extraction protecting the thin buccal bone. At second stage surgery, all implants were asymptomatic, immobile, and osseointegrated. The soft tissue anatomy was clinically acceptable in all patients. Radiographic examination of all 9 implants showed no peri-implant radiolucency at the end of a year.

Conclusion: 

Successful osseointegration and complete bone healing were observed for all patients. The new extraction technique was found to be effective in immediate implant cases in order not to damage the thin plate of buccal bone.

Dental implants are frequently used for the replacement of missing teeth for the last 20 to 25 years. One drawback to the conventional dental implant placement is the amount of time required to complete a procedure. After the insertion, the implant is traditionally submerged beneath the soft tissues to facilitate the achievement of osseointegration. A 3 to 6 month of time is required before the second surgery for the exposure of the implant and confirmation of its anchorage in bone.¹

Today, immediate implant placement at the time of tooth extraction is sometimes preferred to shorten this treatment period. The placement of implants immediately on, or shortly after, tooth extraction has proven to be a predictable treatment strategy with a very high rate of success.^2–4 Immediate implant placement has several advantages, such as reduction of the number of surgical treatments, reduction of the time between tooth extraction and placement of the definitive prosthetic restoration, prevention of bone resorption, and preservation of the alveolar ridge in terms of height and width, which in turn has esthetic and functional benefits.⁵

However, it has been reported that immediate implant placement may be adversely affected by the presence of infection and lack of soft-tissue closure, flap dehiscence over the extraction site, particularly when barrier membranes have been used for guided bone regeneration.⁶ Longitudinal studies have reported survival rates exceeding 90% for immediately placed implants after 6 months to 11 years of functional loading.^1,7

One of the most important points in immediate implant placement is the atraumatic extraction of the tooth to preserve a maximum amount of bone around the tooth and to provide primary stability. The aim of this article is to present a new minimally invasive technique using the implant drills to help in the extraction of the tooth.

Cases

Surgical Procedures

Nine patients (7 women and 2 men) aged 24 to 60 years having dental caries and root/crown fractures where the fracture line is deep in the socket were referred to Istanbul University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, for the extraction of their teeth (Table 1). These patients were selected for replacement by an implant immediately after extraction. Inclusion criteria for the procedure were presence of at least 4 mm of bone beyond the root apex, the absence of acute signs of infection or inflammation in the treatment area, and the absence of systemic pathologies that would contraindicate bone healing around implants. Heavy smokers and cases with absence of primary stability were excluded. Implant sites showing bone fenestrations, bone dehiscences, or peri-implant bone defects exceeding 2 mm were excluded from the study.

Table 1: List of Patients, Regions of Implant Placement, and Loading Times

In each patient, the intra-arch relationship was evaluated using diagnostic casts. Periapical and panoramic radiographs and computerized tomography scans were also obtained if necessary.

Preparation for surgery was made according to standard protocols. After administration of local anesthesia (2% ultracaine with 1:100,000 epinephrine), the teeth were carefully extracted. In order not to traumatize the surrounding bone during elevation, implant drills were placed in root canals to thin the root walls giving way to extraction applying quite less force minimizing the risk of traumatizing the thin buccal bone. No incisions were made and no flaps were reflected (Figs. 1–6). The implant sites were prepared with standard drills using the bony walls as a guide, as palatally as possible. After implant site preparation, a periodontal probe was used to explore and estimate the integrity of the bony walls of the alveolus, and periapical radiographs were taken to confirm the total removal of the root remnants. The longest and the widest possible implants (Astra Tech AB, Mölndal, Sweden) were placed at the buccal-palatal level of bone crest without considering the bone height at the mesial and distal levels. All implants placed showed good primary stability. Four implants, which had an insertion torque of 30 Ncm, have undergone immediate loading⁸ (Figs. 7–11).

Fig. 1.: Schematic view of the new atraumatic tooth extraction technique. A broken tooth with the fracture line deep in the socket.

Fig. 2.: Schematic view of the new atraumatic tooth extraction technique. Thinning the walls of the root with a thin implant drill.

Fig. 3.: Schematic view of the new atraumatic tooth extraction technique. The root walls after the drill is out.

Fig. 4.: Schematic view of the new atraumatic tooth extraction technique. Thinning the walls with a thicker implant drill.

Fig. 5.: Schematic views of the new atraumatic tooth extraction technique. Thin walls of the root in the socket.

Fig. 6.: Schematic views of the new atraumatic tooth extraction technique. Removal of the thin walls with a forceps after slight elevation.

Fig. 7.: Treatment steps of Patient 1. Immediate loading was applied. Radiographic view of the tooth before extraction.

Fig. 8.: Treatment steps of Patient 1. Immediate loading was applied. Intraoral view of the patient after the removal of the crown prosthesis.

Fig. 9.: Treatment steps of Patient 1. Immediate loading was applied. Radiograph taken after the insertion of the implant.

Fig. 10.: Treatment steps of Patient 1. Immediate loading was applied. Provisional crown of the patient at the session of implant insertion.

Fig. 11.: Treatment steps of Patient 1. Immediate loading was applied. Intraoral view after the prosthodontic restoration.

Antibiotics (1000 mg of amoxicillin 2 times a day for 5 days), anti-inflammatory drugs, and chlorhexidine mouthwash were prescribed for all patients.

Results

Healing progressed uneventfully in all 9 cases. The use of implant drills to thin the root walls provided atraumatic tooth extraction protecting the thin buccal bone. The surgical implant site preparation and implant placement proceeded uneventfully.

Soft-tissue closure over the implants that were not immediately loaded was achieved within 1 to 3 weeks of surgery for all sites. At second stage surgery, all implants were clinically and radiographically asymptomatic. No peri-implant bone defects were observed or detected by probing around the implants.

The soft-tissue anatomy was clinically acceptable in all patients. Radiographic examination of all 9 implants showed no peri-implant radiolucency at the end of a year.

Clinically and radiographically, there were no differences between the immediate and delayed loaded implants.

Discussion

It is a well-known fact that primary stability of implants depends on surgical techniques employed, bone density, and implant design, particularly the length and diameter of implants.^9–13 Gap formation between the implant surface and the surrounding alveolar bone walls is often a problem in immediate implant placement. In some cases, this gap is left for bone regeneration, and in other cases, the use of barrier membranes, with or without graft materials, are preferred.^5,14 Furthermore, formation of dehiscence and/or fenestration during implant placement may require regenerative techniques. The use of barrier membranes may be associated with clinical complications such as bacterial colonization, infection, and impaired bone healing. Gelb¹⁵ found that 39% of treated sites showed membrane exposure and required premature removal of the membrane. Becker et al¹⁶ had to remove 41% of membranes used because of premature oral exposure. Ormianer et al¹⁷ have stated that all of the losses in the prosthetically restored implants were in the augmented sites. The clinical findings from previous studies showed that 100% of peri-implant bone defects with a bone-to-implant gap not exceeding 2 mm and without fenestration or dehiscence had complete bone healing without the application of any regenerative procedures.^7,18,19 In an undisturbed extraction socket, early osteoid formation begins after 7 days, and mineralisation commences at 21 days and is well advanced by 6 weeks.²⁰ Thus, it would be reasonable to expect spontaneous bone regeneration to occur at immediate implants provided that the blood clot remains protected, irrespective of graft or membrane use.⁷

No graft materials or barrier membranes were used in any of our cases because the technique used for extracting teeth provided the protection of the buccal plate. Cases with dehiscences or fenestrations, which were reconstructed via bone grafts and/or guided bone regeneration, were excluded from this series.

Schiroli¹ has reported that using an implant with a tapered design had several advantages, such as protecting the integrity of the buccal bone and enabling the usage of a longer implant. We have also used implants with the conical seal design (Astra Tech AB, Mölndal, Sweden), which are also tapered in shape.

In immediate implant placement, to preserve the continuity of the bone surrounding, the root is very important for primary stability and long-term success, especially in upper incisors. Sometimes it is not so easy to preserve the thin labial plate during extraction. When the labial plate is damaged, significant resorption of the labial plate occurs irrespective of membrane and/or bone graft use.⁷ In this procedure, we used a new technique for the extraction of the teeth. To prevent damage of the labial plate during elevation especially in root fractures where the fracture line is deep in the socket, implant drills were placed in root canals to thin the root walls, giving way to extraction applying appreciatively less force, and trying to primarily drill the palatal bone wall, minimizing the risk of traumatizing the thin labial plate. Using this technique, there was no damage to the labial plate in all our cases. Furthermore, the technique that has been used required no extra instruments.²¹

The labial plate can also be damaged during the angulation of the implants in upper incisors. To prevent this, the implant sockets are prepared slightly palatal for primary stabilization.

The complete soft-tissue coverage of implants placed immediately after tooth extraction was considered to be an important criterion for clinical success. All techniques that involve the rotation and/or the splitting of a palatal flap to achieve soft-tissue primary closure are considered time consuming and sensitive and require gingival tissue to be at least 4-mm thick.⁵

In this technique, no flaps were reflected and no incisions were made. Osseointegration was achieved for all 9 implants with stability of the soft tissues.

Conclusion

Thinning the walls of the roots before elevation makes it easier to remove the teeth and minimizes the risk of damaging the thin labial wall especially in root fractures where the fracture line is deep in the socket in immediate implant cases. Successful application of this technique can minimize the need of regenerative techniques that may lead to graft or membrane-related complications.

Disclosure

The authors claim to have no financial interest in any company or any of the products mentioned in this article.