#Immediacy 17. Feb 2019

Single BLX implant with WB abutment for molar

A clinical case report by Michael Kristensen, Denmark

This case describes a successful treatment with a Straumann® BLX implant for a single molar using a wide base (WB) abutment. This platform allows an optimal emergence profile and good load distribution.

Initial situation

A healthy 31-year-old non-smoking male patient lost 46 due to recurrent apical pathology a year ago. He returned to the clinic and asked for the tooth to be replaced in order to recover function. The clinical and radiographic assessments showed healed soft tissues and sufficient vertical and horizontal bone availability (Fig. 1).

Treatment planning

As the patient presented healthy adjacent teeth, the treatment with a partial fixed restoration over teeth was rejected. Moreover, the placement of one Straumann® BLX, Roxolid®, SLActive® implant measuring 5.5 x 8 mm RB/WB was planned based on the above-mentioned information. The surgical protocol included an open flap procedure and 8 weeks healing time before loading with a single crown on a Variobase® WB abutment.

Surgical procedure

After mandibular nerve block, a supracrestal incision was performed from #47 to #45. The mucoperiosteal flap was elevated and the implant bed prepared according to the manufacturer's instructions. Since the bone quality was type 1, a full drill protocol up to 5.2 mm was used. Furthermore, due to the hard bone quality, the insertion of the implant included forward and reverse rotations. The design of the new BLX implant allows the primary stability to be controlled. The primary stability of this implant reached 45 Ncm. No bone augmentation was necessary. The healing abutment was hand-screwed and two stitches were placed in order to close the flap (Figs. 2-15)

The patient was prescribed chlorhexidine rinses 0.12% twice a day for a week and ibuprofen 400 mg every 8 hours in case of pain. Wound healing was uneventful and sutures were removed after 7 days. The patient reported no discomfort after surgery.

 

Prosthetic procedure

After 8 weeks healing, a traditional open-tray silicone impression was taken. The new WB abutment is a hybrid between a Bone Level abutment and a Variobase® for Tissue Level. The base of the WB abutment not only enters the implant, but also lies on top of the 5.5 implant, still allowing platform shifting, but also ensuring high stability for the bigger load forces on a molar abutment and crown. This also provides support for the wider emergence profile of a molar crown. In the dental lab, a full contour zirconia crown was milled and cemented onto the abutment. Next, the prosthesis was screwed in with 35 Ncm. The screw access hole was closed with Teflon tape and composite. Occlusion was tested and interferences were removed (Figs. 16-17).

Treatment outcomes

The patient and dentist were completely satisfied with the final result regarding esthetics, health and function. A final periapical x-ray showed a perfect fit of the prosthesis on the implant and stable peri-implant tissues (Fig. 18).