(Manufacturer’s information:) The Straumann® Bone Level Tapered Implant (BLT) is a natural extension of the Straumann® Dental Implant System. It is designed to provide primary stability and flexibility in challenging clinical and anatomical situations. Straumann’s SLActive® implant surface offers fast osseointegration and healing times are reduced from 6 to 8 weeks to 3 to 4 weeks (compared to SLA®). As a result, secondary stability is achieved faster and the patient’s overall treatment time can be shorter. This scientifically proven implant technology is complemented by a diverse prosthetic portfolio of abutments and customized bars.

Patient history

A 35-year-old Asian woman, non-smoker, in good general health, was referred after horizontal root fracture of the left maxillary central incisor (Figs. 1, 2). She reported that she suffered from a trauma several years before and that the broken tooth was severely discolored and endodontically treated before fracturing. Clinical examination revealed a horizontal root fracture below the gingival level. The periodontium was healthy with no sign of infection. Radiographic examination showed that the fracture had extended to the bone level. The inter-maxillary relationships were normal. Analysis of the smile showed a high lip line.

Treatment plan

Tooth #21 was diagnosed as hopeless. From a periodontal point of view, the clinical situation was considered as favorable: gingival margin at the same level as adjacent central incisor, mesial and distal papillae present and in proper position. The patient underwent computerized tomography to evaluate the available bone volume in the apex area of #21 as well as the integrity of the buccal plate of #21 (Fig. 3). The examination of the CBCT showed that the buccal plate was intact 3 mm below the gingival level; correlated to the clinical examination, the future extraction socket was determined as Class I of Elian [1]. The bone volume correlated to the axis of the tooth and was considered as favorable for immediate implant placement, Class I of Kan [2]. Immediate implant placement after extraction of #21 was planned. Immediate temporization was intended, subject to sufficient primary stability of the implant. The implant chosen for the procedure was a Straumann® Bone Level Tapered Implant 4,1 × 12 mm.

Surgical procedure

Tooth #21 was extracted atraumatically without raising a flap or osteotomy (Fig. 4). The extraction socket was meticulously cleaned and rinsed with Betadine (Purdue Products L.P., Stamford, CT). The drilling sequence included 2.2 mm, 2.8 mm and 3.5 mm drills (Fig. 5). The counter-sink drill or tap was not used in this case to safeguard sufficient primary stability. The implant was placed with a final torque of 45 N-cm (Figs. 6, 7). In its final position, the implant platform lay 4 mm under the ideal gingival margin (compared to adjacent central incisor, Fig. 8) A titanium temporary abutment for the crown was placed and a laboratory-made shell was positioned without interference of the temporary abutment (Fig. 9). Before placing the provisional crown, the gap between the implant and the buccal plate was filled with a particulate bone augmentation material. The screw retained temporary crown was then torqued to 35 N-cm (Fig. 10). Three months after placement, an implant level impression was taken for final restoration. Follow-up ten months after implant placement showed a preserved gingival contour (Figs. 11, 12).

Conclusion

Immediate implant placement and temporization, when properly indicated, has three main advantages: timing, biology and prosthetics. Treatment time and number of surgical procedures are reduced compared to a delayed approach. From a biological standpoint, using a slow-resorbing material to fill the gap between the implant and the buccal plate enables predictably preserved bone volume. The provisional crown supports the gingival architecture and helps maintain the pre-existing positions of the gingival margin and mesial and distal papillae. From a prosthetics perspective, placing an implant retained provisional crown on the day of surgery simplifies the temporization in the anterior area, allowing the patient to leave the office on the same day with a fixed provisional. The success of this procedure relies on three basic principles: proper indication, atraumatic extraction and sufficient primary stability of the implant. The latter depends widely on the choice of the implant design and drilling protocol, which should considered for greater primary stability.

This case was a collaboration between Dr. Leon Pariente, ­­Dr. Karim­ Dada, Dr. Marwan Daas and Dr. Romain Cheron.

Acknowledgments: the authors would like to thank ­Asselin Bonichon­ for the laboratory work.