A clinical case report by Krzysztof Chmielewski, Poland
Dental implants have become a successful restorative option for replacing missing teeth. However, the need to disconnect and reconnect the prosthetic components can be considered one of the limitations of the standard prosthetic protocol for implant treatment.
The concept of one abutment at one time was first described in 2010 by Canullo et al1. This concept was introduced as a reduced invasive prosthetic protocol to minimize soft and hard tissue trauma. The therapy is based on delivering the final prosthetic abutment right after an immediate implantation procedure, which will never be unscrewed again. This represents a significant challenge for the dental technician, who therefore plays an essential role in the success of this therapy. This protocol aims to protect hard and soft tissues by minimizing the number of prosthetic component replacement events, as these frequent abutment exchanges may disrupt the surrounding peri-implant mucosal barrier, causing microtrauma in this area and, ultimately, marginal bone loss.2
Correct case selection and extremely precise implant placement are crucial here. With the help of digital workflows, our chances of transferring the implant position from the plan to the oral conditions increase significantly. A harmonious interdisciplinary workflow between the dental technician and the practitioner is essential, since it also promotes long-term customer loyalty for the dental technician.
The following 5-year follow-up case report shows the steps and the successful outcomes of an immediate, fully guided surgical treatment using a Straumann® Bone Level Tapered ø 4.1 mm SLA® 14 mm implant with the one abutment – one time protocol.
A systemically healthy 44-year-old female patient came to our clinic looking for an esthetic and fast solution for one of her hopeless teeth in the anterior area. She reported being a non-smoker with no medication or allergies.
Her dental history revealed trauma to the left upper canine due to a concussion a couple of years ago. However, she did not give this much thought until she noticed color changes and occasional discomfort. She was afraid of losing her tooth as she did not want to be left with a black space that would prevent her from talking or smiling confidently in public. Therefore, her main request entailed an esthetic, safe, predictable, and minimally invasive solution. In addition, she highlighted that she did not want a metallic edge to show, that she was aware of the digital developments and wanted a modern solution.
In the extraoral examination, when smiling and speaking, the patient showed the cervical edge and the gingival margin of teeth #22 and #23 (Fig. 1). The intraoral examination revealed slightly gingival recession on tooth #23 (Fig. 2). Additionally, the tooth was percussion test positive, pulp vitality test negative, and no fistula was observed. Bleeding was detected during probing, and the tooth presented slight dyschromia.
The radiographic assessments were performed, and the CBCT showed a radiolucent image with well-defined and smooth margins located in the upper third of the root of tooth #23, compatible with external cervical resorption. Furthermore, the buccal wall was thin (Figs. 3,4).
This clinical scenario was defined as surgically and prosthodontically complex by the ITI SAC classification (Fig. 5).
Following a thorough discussion of the various treatment options with the patient and considering her main request, it was decided that immediate implant placement with bone augmentation would be the treatment option that fulfilled all her needs. This procedure would be performed following the atraumatic extraction of tooth #23 to preserve the remaining bone. Therefore, the treatment workflow included:
1. Digital planning for guided surgery and immediate loading.
2. Preparation in the dental laboratory before surgery: surgical guide, final hybrid abutment based on RC Variobase® abutment (Institut Straumann AG, Basel, Switzerland), temporary crown, and ZrO coping for the final crown. The custom abutment was created using a Zirconia disc (Katana HT 12, Kuraray Noritake, Hattersheim, Germany) and bonded, using an opaque cement (Panavia V5, Kuraray Noritake, Hattersheim, Germany), to a titanium base abutment (Straumann RC Variobase crown abutment)
3. Atraumatic tooth extraction.
4. Fully guided surgery with guided placement of Straumann® Bone Level Tapered ø4.1 mm SLA® 14 mm
5. Augmentation of the post-extraction socket with Cerabone® (xenograft).
6. Delivery of the final hybrid abutment and temporary crown on the day of surgery.
7. Final restoration after 5 months.
Before surgery, a surgical guide, the final hybrid abutment, temporary crown, and ZrO coping for the final crown were prepared in the laboratory (Fig. 6).
The region of tooth 13 was anesthetized with local infiltration anesthesia (lidocaine 2% with epinephrine 1:100,000). The atraumatic tooth extraction was designed to preserve as much of the hard and soft tissues around the tooth as possible (Fig. 7).
Once the tooth was extracted, the correct fit of the surgical guide in the mouth was verified. The fully guided flapless surgery involved the immediate placement of Straumann® Bone Level Tapered ø 4.1 mm SLA® 14 mm Loxim™ Roxolid® following the manufacturer's instructions to ensure primary stability in position #23. The implant bed was prepared to ∅ 2.2 mm with the pilot drill, then widened to ∅ 2.8 mm, ∅ 3.5 mm with the BLT drill, then to ∅ 4.1 mm with the profile drill, and continued with the ∅ 4.1 mm Straumann® BLT Tap, and the final preparation depth was finally checked with the ∅ 3.5 mm depth gauge. The coronal part of the implant bed was prepared with the ∅ 4.1 mm profile drill. Finally, the threads were precut with the ∅ 4.1 mm tap drill over the full depth of the implant bed (Fig. 8). The implant was placed with the handpiece in a clockwise direction using a maximum speed of 15 rpm and torqued to 35 Ncm. The implant shoulder was positioned about 3–4 mm below the prospective gingival margin (Fig. 9).
An augmentation procedure was indicated because the orofacial bone wall was less than 1 mm and bone was missing cervically. The augmentation was made with Cerabone® (xenograft). The definitive hybrid abutment was individualized and polished, and the provisional crown was then delivered immediately without contacts and occlusion (Figs. 10,11).
A Center of Dental Education (CoDE) is part of a group of independent dental centers all over the world that offer excellence in oral healthcare by providing the most advanced treatment procedures based on the best available literature and the latest technology. CoDEs are where science meets practice in a real-world clinical environment.
At the follow-up appointment the tissue healing was assessed and proved to be uneventful.
Five months after surgery, the site had healed and the implant osseointegrated. An optimal bone contour was observed in the region of tooth #23, and no signs of inflammation were observed in the surrounding soft tissues (Fig. 12). The final crown (by Bjorn Roland MDT) was fabricated in the laboratory (Fig. 13). In this case, a zirconium oxide coping of perfect fit for the abutment was designed, produced, and delivered before surgery. For veneering the framework, CZR ceramic in shade A2/A3 (Kuraray, Germany) was used and fired according to the manufacturer’s instructions in a Dekema Austromat 624 furnace (Kulzer, Hanau, Germany)
The final crown was cemented, and all excess cement was removed after the final setting (Fig. 14). The occlusion was checked, and oral hygiene instructions were given. The frontal view shows a very natural and esthetic outcome (Fig. 15).
Controls, including clinical and radiographic assessments, were performed at annual follow-up visits. The CBCT images showed a stable bone level over time (Fig. 16).Furthermore, the 5-year follow-up clinical outcome demonstrated the stability of the surrounding soft tissues and a very natural and esthetic outcome maintained over time (Fig. 17).
In this clinical case, the use of definitive abutments reduced costs and trauma while achieving outstanding results. The patient was delighted with the predictability of the treatment and the esthetic and functional outcomes. During the 5-year follow-up visit, she mentioned: “Despite the fear of surgery, I am very glad that I trusted the doctor's recommendation. After five years, I can keep smiling and enjoying the treatment effect every day.”
Minimally invasive implantology brings many benefits to the patient. However, suitable cases and tools are of paramount importance. Before choosing a treatment technique, it is worth considering the type of solution using a digital workflow.
