Immediate Implant Placement and Provisionalization Using the Patient’s Extracted Crown: 12-Month Follow-Up

The field of implant dentistry has evolved significantly over the past few years. Major improvements have included the development of novel materials, techniques, and equipment that, combined, have made the immediate placement and provisionalization of single implants a viable and predictable treatment option with long-term success rates reaching between 90% and 100%.^1-8 Although this strategy has some important advantages when compared to traditional implant protocols, such as time efficiency, immediate esthetics, and improved patient comfort,¹ the immediate placement of implants may not avert hard- and soft-tissue remodeling and, therefore, is considered a risky procedure by some researchers and clinicians.⁴ Nonetheless, immediate implant placement and provisionalization has been used in many patients.^9-11

Bruno et al, while investigating the specific positioning of provisional crowns' contact areas on the maintenance of interproximal papillae, demonstrated that the use of immediate techniques resulted in interdental papillae that were superiorly maintained and dental implants that were associated with less soft-tissue remodeling at the gingival level.¹² Esposito et al¹³ and Schropp and Isidor¹⁴ systematically reviewed the literature in regard to the use of immediate placement of implants in fresh extraction sockets and concluded that such a technique is a viable treatment option that could be associated with better esthetic outcomes and higher levels of patient satisfaction as compared to delayed placements. The authors have also stated that immediate placement procedures are technique-sensitive and may be more difficult to execute than conventional procedures, thereby suggesting that immediate techniques should be restricted to well-trained dental teams.¹⁵

Due to patients' high demands for esthetics in the smile zone, the restoration of extracted maxillary incisors is currently considered as a major indication for the use of immediate placement procedures with provisionalization. Becker et al investigated the immediate provisionalization of single-tooth implants (5.8 mm or longer) in fresh sockets and reported that provisionalization of implants is a favorable and predictable treatment if some minimum criteria are met (eg, insertion torque = 15 Ncm, insertion stability quotient = 50, and apex bone quantity = 3 mm).¹⁶ Presently, the establishment of primary stability is deemed to be the cornerstone of immediate loading techniques and has been implicated as a major factor in achieving long-term favorable esthetic outcomes.^2,17-22

Other factors, such as accurate positioning of the implant and the use of a bolted prosthesis, have also been positively correlated with the healing and maintenance of soft tissues in immediate placement/provisionalization.²³ Malchiodi et al investigated the relationship between the interproximal alveolar crest and soft tissues and its influence on long-term esthetic results (3-year follow-up). According to their findings, a strong correlation exists between hard and soft tissues, wherein the maintenance of the architecture of the tissues (around the surgical site) is a key factor for achieving long-term optimal esthetic outcomes.²⁴ In this regard, if bone support is deficient or a thin biotype is detected before surgery, then a graft procedure (connective tissue) is essential for the maintenance and stability of periodontal tissues.^25,26 In a clinical and radiographic cohort study by Pozzi and Mura, results indicated that the use of immediately provisionalized tapered-body implants with internal conical connections and built-in platform shifting (NobelReplace Conical Connection, Nobel Biocare, nobelbiocare.com) favored the maintenance of marginal bone crests and the esthetics of the surrounding tissues in both fresh sockets and healed bone.²⁷ Therefore, the main objective of the present study is to describe a clinical procedure wherein a technique based on immediate implant placement and provisionalization associated with grafting (bovine bone and connective tissue) was used to restore a maxillary incisor with severe external resorption.

A 23-year-old female patient sought dental care at the Endodontics Clinic of the Positivo University (Curitiba, PR, Brazil) for evaluation of a maxillary central incisor (tooth No. 8). The patient's chief complaint was the presence of slight mobility of the tooth that resulted from a trauma that took place 10 years before initial clinical evaluation. Anamnesis procedures revealed that pain symptoms were not perceived at the time of trauma or in subsequent years.

The patient's medical and dental history did not include any restrictive pre-existing conditions (eg, uncontrolled heart disease or diabetes) for the execution of dental treatments. General and detailed clinical examination revealed a tooth with preserved anatomy and color surrounded by healthy periodontal tissues (ie, no pockets or bleeding detected upon probing). Vitality testing resulted in a negative response to cold stimulus ( -50C, Endo-Ice, Maquira, maquira.com.br). Cone-beam computed tomography (CBCT) (field of view 5 x 5, 0.14 voxels, 25 seconds) (PreXion3D, PreXion, prexion.com) was performed to further evaluate the periapical regions of bone (Figure 1 and Figure 2) and revealed the presence of extensive external cervical resorption (ECR) with the maintenance of interproximal bone crests. Based on the most recent ECR classification proposed by both the European Society of Endodontology and American Academy of Oral & Maxillofacial Radiology, Patel et al classified the ECR observed in the present study as 3BP (wherein "3" means the lesion height extends to the mid-third of the root, "B" means >90 degrees and 180 degrees, and "P" denotes probable endondontic involvement).²⁸

The proposed treatment plan was atraumatic extraction of the tooth followed by immediate implant placement accompanied with a bone graft (bovine origin) for gap filling and a subepithelial connective graft for stabilization of periodontal soft tissues. Restorative procedures included the immediate provisionalization of the implant using the extracted clinical crown adapted as a temporary crown. The rationale behind the proposed treatment plan was to enable maintenance of the patient's esthetics while restoring the function of the lost element.

Surgical procedures were performed under local infiltrative anesthesia (articaine 4% with epinephrine [1:100,000]) applied to the buccal vestibule and palate. An intracrevicular incision was made from the distal of the adjacent tooth, thereby creating a flap that would allow a visual assessment of the area affected by the ECR (Figure 3). The atraumatic extraction was performed using a scalpel (n#15c, SOLIDOR^®, solidor.com.br) to preserve the majority of periodontal structures.

A morse tapered implant (MT, 3.5-mm diameter x 11.5-mm length, Neodent, instradent.us) was installed 3 mm apical to the gingival margin (per manufacturer's instructions) in the prepared surgical site. The establishment of primary stability was confirmed with a torque wrench that indicated the presence of 30 Ncm insertion torque. Next, a 1-mm thick bovine graft (Lumina-Bone, Critéria, criteria.com.br) was placed between the implant and the buccal bone plate to obliterate any gap present, while a second graft (from harvested connective tissue) was placed over the first graft to serve as a biological barrier during the healing process and to increase the gingival volume (Figure 4). A vertical suture was performed using nylon thread (5-0, Ethicon, Johnson & Johnson, ethicon.com).

The extracted clinical crown was then separated from the root and was prepared and adjusted to fit the morse tapered implant's prosthetic abutment using light-cured composite resin (shade A2, Empress^® Direct, Ivoclar Vivadent, ivoclarvivadent.com) The adapted crown was screwed into the implant and occlusal adjustments were made to avoid contacts (centrally, laterally, and in protrusion) (Figure 5).

The patient was prescribed a broad-spectrum antibiotic (amoxicillin, 500 mg, every 8 hours, 7 days), an anti-inflammatory (nimesulide, 100 mg, every 12 hours, 3 days), and an analgesic (paracetamol, 750 mg, every 8 hours, 3 days) for the control of infection, inflammation, and pain, respectively. Routine postoperative oral hygiene instructions were given to the patient before discharge, and sutures were removed 10 days after surgery.

A 30-day follow-up clinical appointment revealed that a satisfactory short-term esthetic outcome was achieved. At 90- and 360-day follow-up clinical sessions, a significant improvement in periodontal health was observed, with maintenance of gingival volume, a rising profile, and interproximal bone crests, which, combined, favored the gingival esthetics that were achieved (Figure 6 through Figure 8). (Author's note: The rationale for the presentation of an x-ray at 12-month follow-up is simply based on the fact that the author's CT device was down at the time; therefore, a 12-month CT scan is not available.)

The objective of the present case report was to describe the restoration of a maxillary central incisor (tooth No. 8) affected by severe ECR. The treatment plan proposed included an immediate implant placement protocol followed by immediate provisionalization of the implant using the crown of the patient's extracted tooth. The treatment plan resulted in immediate esthetically pleasing outcomes for the patient while the natural contours of the gingiva and papillae were maintained.

The results reported herein demonstrate that the surgical protocol selected allowed the correct positioning of the implant while enabling primary stability to be achieved, as confirmed by the insertion torque values (30 Ncm). The selection of the patient's clinical crown for the implant provisionalization provided the surrounding tissues with ideal physiological distances between the points of contact and the alveolar bone crest, thereby resulting is periodontal tissues that maintained and adapted exceptionally well.

Together these factors resulted in optimal gingival esthetics and minimal disturbance of the patient's psychological comfort in the short and long terms. Periodontal biotype assessment is fundamental for the success of implants placed using the techniques described herein. The proper selection and correct usage of biomaterials for gap filling and guided tissue regeneration are critically important in attaining ample support for both hard and soft tissues.²⁹ Though the patient's buccal bone plate and gingival tissues were extremely thin, the types of biomaterials used, in conjunction with the placement technique performed, ensured the maintenance of tissue architecture and prevented tissue remodeling and subsequent retraction. The results reported suggest that the use of a morse tapered implant was a contributing factor that favored the maintenance of the gingival bone crest and improved the esthetics of the adjacent gingival tissues during the 12-month follow-up.

The present clinical report has demonstrated the utility of an immediate implant placement protocol followed by immediate provisionalization using the patient's natural crown. The results reported clearly indicate that the protocol used resulted in the long-term maintenance of gingival health, contours, and volume. The use of biomaterials along with immediate provisionalization with the patient's crown proved to be a feasible approach.

Tatiana Miranda Deliberador, PhD
Graduate Program in Dentistry
Positivo University
Curitiba, Brazil

Gilmar José Begnini, MS
Graduate Program in Dentistry
Positivo University
Curitiba, Brazil

Flávia Tomazinho, MS
Graduate Program in Dentistry
Positivo University
Curitiba, Brazil

Carlos Eduardo Edwards Rezende, PhD
Graduate Program in Dentistry
Positivo University
Curitiba, Brazil

Fernando Luis Esteban Florez, PhD
Department of Restorative Sciences
Division of Dental Biomaterials
University of Oklahoma Health Sciences Center
Oklahoma City, Oklahoma

Denise Piotto Leonardi, PhD
Graduate Program in Dentistry
Positivo University
Curitiba, Brazil