Dr. Eimear O’Connell presents a single anterior implant crown case in a young patient
This young man attended the practice complaining that his adult tooth was missing on the upper left lateral site, and the deciduous tooth was starting to come loose. He wanted to find out more about what the options were for treatment.
The patient didn’t want to wear a denture as he is only 23, and he did not want to damage his adjacent teeth in any way. This immediately ruled out an adhesive bridge. I discussed using orthodontics to correct his occlusion as he has a Class III malocclusion.
He did not want to wear a brace as he had just started at art college. The treatment may even have included an osteotomy, but would definitely have to involve having teeth extracted in the lower arch.
The patient did not want to go through such extensive treatment and wanted a conformist approach accepting his mal-occlusion and replacing the baby tooth with an implant-retained crown in the space available once extraction was carried out.
Past dental history
The patient has been a regular dental attender at a practice near his home in England and has good oral hygiene and no fillings.
Past medical history
The patient is medically fit and well and is a nonsmoker.
At the first visit, he was examined, and extraoral and intraoral findings were clear. He has a Class III malocclusion, which will in part determine the outcome of the treatment. Study models and a periapical X-ray of the upper left bicuspid (ULB) were taken. His community periodontal index of treatment needs (CPITN) was 111/110. He has a thin, highly scalloped periodontium, and bone-sounding revealed adequate bone width.
His past dental history is uneventful, but he had never had any invasive dentistry, not even a local anesthetic, so we had to discuss what would be involved in the extraction of the deciduous tooth and subsequent surgical placement of the implant.
There were difficulties with the over eruption of the lower left canine, and this was fully discussed and presented in the treatment plan. He also has a reverse overbite, and so room to lengthen and widen the new implant-retained crown at UL2 was going to require modifying his existing teeth.
This is clearly illustrated by Figures 3, 4, and 5. He has thin and highly scalloped periodontal biotype. He has a high lip line during full smile.
After the initial consultation, once all the necessary preoperative information was gathered over a 2-month period, and after a verbally agreed treatment plan was finalized, the patient was sent a full treatment plan and consent forms for implant placement. This included consents to permanently alter the incisal length of some of the anterior teeth, both upper and lower.
The adjacent teeth, i.e., UL1 and UL3, needed some distal and mesial reduction, respectively, to allow placement of a sufficiently large tooth at the ULB site to give a more balanced result. We were slightly limited for space, as the patient did not want to move the teeth orthodontically. Careful measurements were required to ensure a sufficient mesial and distal clearance from the adjacent teeth roots of at least 1.5 mm and preferably 2 mm.
A 3 mm Astra Tech™ implant was used as the replacement, as this allowed the interdental clearance to be adhered to. A clear surgical stent was used to guide the surgery. It is shown on the implant model in Figure 8.
The deciduous tooth was removed atraumatically using periotomes and luxators on February 1, 2011. A temporary denture was used as the provisional restoration and was fitted at this visit.
The patient returned 5 weeks later for placement of the implant. As discussed earlier, a 3.0 OsseoSpeed™ Astra Tech 13-mm implant (Dentsply Implants) was placed using an open surgical method, and the site was closed using 5x 5-0 Monocryl® (Ethicon) sutures.
After 2 days, the sutures were removed. Healing was uneventful. The temporary denture was used until the healing abutment was placed on June 9, 2011. Two weeks later, an open tray 3.0 pickup impression was taken for the laboratory to make a customized abutment and cement-retained crown, which was fitted with a temporary bond on August 15, 2011. The tissue depth at the time of taking the impressions for the laboratory was recorded as 2 mm. A facebow record and bite were recorded along with a new alginate impression of the newly adjusted lower teeth.
The patient is studying design at the Edinburgh College of Art and wanted to include his models and a gold crown for part of his final-year presentation. We subsequently made a cement-retained gold shell crown, which can be interchanged with the porcelain one should the patient desire it. Once he saw it in situ, he preferred the porcelain. The restoration has been bonded in with a temporary bond, so as to be retrievable in future if necessary.
There was insufficient room for the new crown without incisal reduction of LL3 and LL2 and reshaping the distal aspect of the UL1 and mesial aspect on UL3. These minor adjustments were fully discussed with the patient before the commencement of treatment.
The prognosis for the patient’s dentition is very favorable as he is a highly dentally motivated individual. He has returned for regular checkups, and presently his implant can be classified as successful according to the criteria defined by Roos, et al., (1997).
He is a nonsmoker and does not appear to clench or brux. He is planning to live in Edinburgh so will be able to return for regular reviews.
The patient was very happy with the results, and he has a good understanding of the maintenance required to keep his dentition healthy, including the implant. He is young, and therefore, the implant will have many years to survive if he lives to the average life expectancy age. It is in the esthetic zone, and so any problems will be very obvious.
I paid particular attention to the occlusal issues in this case since the lower canine is in working contact with the implant on the labial surface. Since he has a reverse overbite, this will inevitably place more stress on the restoration over the years. I deliberately used a cement-retained restoration in the hope that any occlusal overload should make itself apparent by debond rather than potentially causing a screw fracture or implant fracture.
Perhaps I would now place an immediate implant with some buccal grafting with xenograft/autograft to try to ensure longevity of the buccal plate.
My increased experience of working in the esthetic zone has led me to adopt a more conservative surgical approach, especially when dealing with thin, scalloped periodontium.
One can clearly see some dark shine through from the implant, and if this concerned the patient, either a customized zirconia abutment or some soft tissue grafting could be carried out to improve this situation. I try to use curvilinear and U-shaped peninsula flaps as recommended by Anthony Sclar to increase the thickness of the labial mucosa.
The photos and X-ray show a 2-year follow-up. The patient is maintaining healthy periodontium around the implant, so it will hopefully last for many more years.
- Roos J, Sennerby L, Lekholm U, Jemt T, Gröndahl K, Albrektsson T. A qualitative and quantitative method for evaluating implant success: a 5-year retrospective analysis of the Brånemark implant. Int J Oral Maxillofac Implants. 1997;12 (4): 504-514.
- Sclar A. Soft tissue and Esthetic considerations in Implant therapy. Chicago, Illinois: Quintessence; 2003.