Authors:
Marcos Motta, DDS, MSc
, Rodrigo Monsano, Glauco Rodrigues Velloso, DDS, MSc, Júlio César de Oliveira Silva, DDS, MSc, Eloá Rodrigues Luvizuto, MSc, PhD, Rogério Margonar, MSc, PhD, and Thallita Pereira Queiroz, MSc, PhD

Abstract:

The placement of dental implants and subsequent placement of immediate temporary dentures after extractions has become a treatment modality accepted by the scientific community. In addition to the functional factor, the surgical procedure in a single stage in the anterior region of the maxilla offers an esthetic appearance, and relieves the psychological concerns of patients. To guarantee the success and longevity of treatments performed, the fabrication of surgical guides is a helpful method in these situations. Guided surgery has gained attention because it restores esthetics with immediate restoration, provides the patient with comfort in addition to dispensing with the need for performing surgical flaps. This auxiliary method allows the position and design of the implant, as well as the perforation sequence to be programmed, thus optimizing the clinical results. In this study, the authors present a clinical case of a patient who was submitted to extraction and subsequent implant placement with immediate loading in the anterior region of the maxilla, performed in a satisfactory manner.

To the editor: The loss of an anterior tooth causes functional, esthetic, social, and psychological disturbances to the patient. In these situations, the ideal approach is to replace the absent tooth immediately, in a surgery that is not very traumatic and with predictable results.
The immediate placement of dental implants after extraction, with subsequent placement of a temporary dental crown, is a procedure that has been discussed and well documented in the
literature. Immediate loading, contrary to that which has been speculated, appears to play a beneficial role in the osseointegration process and is a well-established practice.
In this sense, the use of implants with morse cone prosthetic platforms appears to minimize perimplant tissue bone loss, and consequently reduce the retraction of soft tissues around implants.
This increases the esthetic predictability of patients, especially in the anterior region of the maxilla, in which the maintenance of the thin vestibular bone plate becomes a delicate question.
In conjunction with the advancements in the development of osseointegrated implants, guided surgery allows the professional to obtain greater precision in the diagnosis, planning, and implementation of patients. With the help of software programs from tomographic cuts, surgical-prosthetic planning may be done in a simple and safe manner, in which all the data about positioning of the implants are transferred to a surgical guide by the computer-aided design/computer-aided manufacturing process, thus avoiding errors during surgery.
In this study, we present a very successful clinical case of guided surgery in the anterior region of the maxilla, in which extraction, immediate implant placement with immediate loading were performed in the same operative time.

Clinical Report

The patient, a 30-year-old woman, presented to the clinic with a tomographic examination that had shown evidence of root resorption of tooth 21, which had been endodontically treated after being traumatized during the patient’s fall from her own height, when she was 17 years old (Fig. 1).
Clinical examination showed good periodontal health and grade II mobility. The patient’s periodontal phenotype was classified as thick, by means of visual evaluation and transparency on probing (Fig. 2).
The casts of the patient were mounted in a semiadjustable articulator, and diagnostic waxing was performed. The treatment proposed and accepted by the patient was replacement of the loss tooth with an individual porcelain crown, supported by an osseointegrated implant.

Description
FIGURE 1. Initial clinical image.
FIGURE 2. The periodontal phenotype of the patient was classified as thick through visual assessment and transparency on probing.
Analysis of the initial tomograph provided the possibility of extraction, followed by immediate implantation in element 21. The professional team together with the patient decided on implantation using the guided surgery method (Neoguide, Neodent Implantes, Curitiba, Brazil) and placement of a definitive porcelain crown, cemented in a single clinical time, immediately after extraction and implantation.
A tomographic guide was fabricated of transparent heat-polymerizable acrylic, from the mounted models.
Description
FIGURE 3. Guide to computed tomography scan with 8 circular markings on gutta percha.
Eight circular marks in gutta percha were added, and the patient was submitted to a tomographic examination, using the guide (Fig. 3).

A tomograph of the guide alone, with a stock tooth positioned in the region of element 21, was also taken so that the 2 image files could be inserted into the Dental Design program. From the digitized image of the patient’s maxilla and that of the tomographic guide, the program united the 2 tridimensional images, and after choosing the diameter and length of the implant, the ideal position in relation to the biologic parameter was discussed and approved by the team (Fig. 4).
A surgical guide was fabricated by the Neoguide system, by means of stereolithography and from it, using the guided surgery kits, Neoguide burs and rings, an analog of the Implant Titamax Ex Cm was placed in the working model. An Exact CM Universal abutment measuring 3.3 X 6 X 2.5mm was chosen with the use of the NeodentCm selection kit and inserted into the model (Fig. 4). After scanning with the CadCam Neoshape system, a shell was produced in zirconium, and a first layer of porcelain, opaque and dentin, was applied on this substrate (Fig. 5).
For the surgery, 2 tubettes of infiltrative anesthesia (lidocaine hydrochloride 1:100,000) were administered. An endeavor was made to perform the extractions in the least traumatic manner possible, with the use of periotomes and a Neodent Extractor dental extractor (Fig. 6).

Description
FIGURE 4. Implant placement planning by computed tomography.
FIGURE 5. Making the surgical guide by Neoguide system. A pillar Exact CM Universal with measures 3.3 X 6 X 2.5mm was chosen from the use of the selection kit NeodentCm and installed in the model. After scanning your CadCam Neoshape system, was producing casquete in zirconia, and a first layer porcelain, opaque and dentin was applied on this substrate.
FIGURE 6. Extraction of the least traumatic way possible and positioning the surgical guide.
After extraction, extensive curettage was performed, followed by irrigation with saline solution, to remove possible remainders of material or tooth particles and granulation tissue.
The surgical guide was positioned, and with the use of an adequate sequence of burs guided by the rings, bone perforation was performed under irrigation, and in the site of tooth 21, and implant (3.5 X 15 mm, Titamax EX Cm, Neodent) was placed immediately, and anchored on the palatine wall of the alveolus, with an insertion torque of 50 N. The space between the implant and the walls of the alveolus was filled with fine grain bovine bone substitute (Bio-Oss, Geistlich, Switzerland), and condensed with the use of a titanium instrument (Fig. 7).
Description
FIGURE 7. Milling of the implant installation, biomaterial in the spaces between the implant and the walls of the alveolus.
The Exact CM Universal abutment previously selected was inserted and received definitive torque of 15 N, recommended by the manufacturer. The base of the previously manufactured crown was tested in position (Fig. 8) and transferred by impression-taking the mercaptan of medium consistency. The new model served as a basis for the final application of porcelain.A feldspathic ceramic was used (VitaVM9, Vita Zahnfabrik, Germany).
After being concluded, the definitive porcelain crown received occlusal adjustments and was definitively cemented during the same appointment (Fig. 9).
The postoperative medication included the use of 400 mg Ibuprofen, in 2 daily doses, for a period of 5 days. In addition, amoxicillin (875 mg) associated with potassium clavulanate (125 mg), in 2 daily doses, for a period of 7 days was prescribed. Follow-up for a period of 6 months showed tissue stability. The tomographic examination confirmed the maintenance of bone tissue (Fig. 10).

Discussion

Prosthetic rehabilitation of a single maxillary anterior tooth with a fixed implant supported dental prosthesis is an accepted concept, but in the last decade, the original protocol has been changed to include single-stage surgery. To achieve this, primary stability, considered one of the most important parameters for immediate load application on the implant, is not only a demand for long-term success, but must be respected. Therefore, the treatment has some advantages, guaranteeing its greater population and acceptance by patients. Thus, it diminishes the number of periodic visits during treatment and number of surgical procedures, minimizes postoperative morbidity, dispenses with the use of bone grafts and biomaterials, in addition to presenting a final esthetic appearance closer to the real one.

Description
FIGURE 8. Base prefabricated crown tested in position.
FIGURE 9. Final clinical image.
FIGURE 10. Final clinical image with 6-month follow-up.
In the patient presented, the option was taken to keep the tooth in its alveolus for the maximum length of time, more so because the authors believe that not even dental implants can replace natural teeth, particularly as regards esthetics and function. However, by the pathological development after the trauma, the option of extraction and immediate implant placement with a dental prosthesis became more interesting and justifiable for the patient, particularly in psychological terms.
Nevertheless, immediate loading also has its disadvantages, which may interfere in the follow-up of treatment. There is an increased risk of infection, unpredictable vertical bone resorption, and marginal recession of the attached gingiva, in addition to the possibility of the incorrect surgical placement of the implant,9 which may be overcome with the use of guided surgery, as used in the clinical case presented.
Recently, guided implant surgery, without performing flaps and detachment of the periosteum, has been widely divulged. A guided surgery model is fabricated from tomographic cuts taken with a cone beam computed tomograph, with the help of appropriate software, allowing planning with determination of the location and direction of the implants to be inserted, thereby optimizing the surgical procedure.
In the present patient, the morse cone implant was used, because differently from the other systems, the abutment is connected to the implant by means of an internal connection without a retainer screw, providing a guarantee as regards possible failures of prosthetic components becoming loosened and/or fracturing, guaranteeing long-term stability.
Bearing in mind the clinical history and evolution of the patient, the authors concluded that the model of treatment adopted in this situation was satisfactory, and when well indicated, single-stage surgery, with extraction, implant, and temporary dental prosthesis placement in the same session, may lead to significant results, particularly meeting the esthetic-functional demands of patients.