Guglielmo Zanotti

Application of the "All-on-Four" concept and guided surgery in a mandible treated with a free vascularized fibula flap.

Abstract In this article, we describe the first case in the literature in which 3D computer-assisted treatment planning and guided surgery enabled a patient affected by extreme paraphysiologic mandibular bone atrophy to be treated with a free vascularized fibula flap and, after a period of healing, the flapless installation of 4 immediately loaded dental implants. The computer-fabricated surgical guide allowed placement of the implants according to the “All-on-Four” concept in a proper spatial preplanned position and by tilting 1 implant, avoiding an area of bone discontinuity. Additionally, this technique allowed the production of a prefabricated temporary prosthesis, delivered after implant insertion, which could be immediately loaded. The use of a fibula flap makes it possible to create greater bone thickness while computer-assisted treatment planning and guided surgery provide several advantages over the traditional technique.

Computer-assisted surgery in the lower jaw: double surgical guide for immediately loaded implants in postextractive sites-technical notes and a case report.

Computer-assisted surgery is based on computerized tomography (CT) scan technology to plan the placement of dental implants and a computer-aided design/computer-aided manufacturing (CAD-CAM) technology to create a custom surgical template. It provides guidance for insertion implants after analysis of existing alveolar bone and planning of implant position, which can be immediately loaded, therefore achieving esthetic and functional results in a surgical stage. The absence of guidelines to treat dentulous areas is often due to a lack of computer-assisted surgery. The authors have attempted to use this surgical methodology to replace residual teeth with an immediate implantoprosthetic restoration. The aim of this case report is to show the possibility of treating a dentulous patient by applying a computer-assisted surgical protocol associated with the use of a double surgical template: one before extraction and a second one after extraction of selected teeth.

The use of computer-guided flapless dental implant surgery (NobelGuide) and immediate function to support a fixed full-arch prosthesis in fresh-frozen homologous patients with bone grafts.

Abstract The behavior of fresh-frozen homologous bone (FFB) when used in combination with computer-guided implant surgery has not been investigated yet, and there is a lack of clinical evidence in the literature. The purpose of this retrospective study is to evaluate the implant survival and related fixed full-arch prostheses at the 1- to 5-year follow-up when performed with immediate function using a flapless surgical procedure and computer-aided technology (NobelGuide; Nobel Biocare AB, Goteborg, Sweden) in patients previously treated with FFB grafts. Furthermore, the related values of torque and complications observed were analyzed and discussed. Clinical charts of patients with edentulous arches treated with FFB grafts and NobelGuide system with at least 1 year follow-up were reviewed retrospectively. A total of 65 patients met the criteria of inclusion, receiving a total of 342 implants and 77 full-arch prostheses, with a mean follow-up of 32.87 months (range, 1–5 years). Survival of implants and prostheses was high, reaching 96.5% and 95%, respectively. Factors significantly related to failure of the implants were smoking, position of the implant as last distal abutment, and fracture of basal maxillary bone. Prostheses survival was influenced by bruxism, failure of multiple implants, and torque level of implant equal to 0 at implant insertion. All implants and prostheses failures occurred in the first year. A higher torque level at implant insertion did not correspond to a lower risk of implant failure. Within the limitations of our retrospective study, this treatment modality was predictable with high survival rates and high insertion torque. However, a few implant and prosthetic failures were found, together with several complications.

A New Radiologic Protocol and a New Occlusal Radiographic Index for Computer-Guided Implant Surgery.

AbstractA minimum interarch space of 40 mm along the planned direction of the implant is physically mandatory to allow computer-guided implant placement with the NobelGuide technique. The aim of this paper was to describe a novel radiologic protocol and a new occlusal radiographic index that give the clinician the possibility of identifying patients with limited interarch space. Three patients undergoing NobelGuide treatment of the edentulous upper jaw were selected as candidates for this study. In the first patient, the radiographic occlusal index was built using an addition silicone material to occupy the space between the 2 arches forced into the maximum opening position. In the other 2 patients different silicone materials were used and 2 interpositional wedges were placed in between 2 silicone bites to ensure maximum mouth opening. In the first patient, the bite made with addition silicone alone resulted in distinct noise on computer tomography since the patient was not forced to achieve his maximum opening position. In the second patient the mandibular addition silicone was still quite visible, while in the third patient the condensation silicone was invisible and the quality of the image was excellent with the possibility of measuring maximum opening position and virtually predicting interference with the opposite arch. The new radiological occlusal index made with condensation silicone (Sandwich Index) proved to be effective in reproducing the maxillary forced maximum opening position during the initial planning phase, preventing errors in the inclusion or exclusion of patients suitable for NobelGuide treatment.

Extensive keratinized tissue augmentation during implant rehabilitation after Le Fort I osteotomy: using a new porcine collagen membrane (Mucoderm).

AbstractThe aim of this study was to test a new collagen matrix (Mucoderm) positioned during oral implant abutment connection. A patient previously treated with Le Fort I for bone augmentation and 8 implants showing minimal amount of keratinized tissue was selected for an extensive keratinized tissue augmentation and deepening of the oral vestibule by apically positioning a split palatal flap and palatal grafting with Mucoderm.Clinical data at 9 and 14 days and 1 and 2 months showed resorption of the collagen graft, augmentation of the keratinized tissue around the implants, and deepening of the vestibule, with minimal morbidity and reduced surgical treatment time. However, some vestibular keratinized tissue contraction was evident. The new collagen matrix may be a promising material as a substitute for an autologous gingival/connective tissue graft.Despite the preliminary results of this innovative article, before drawing any general conclusion, the benefit of the procedure should be further evaluated by prospective clinical trials.

La scelta del colore in odontoiatria

Riassunto Obiettivi La corretta scelta del colore puo essere operata con il metodo tradizionale, basato sull’uso di scale colore, oppure utilizzando le recenti tecnologie di colorimetria, spettrofotometria digitale ed RGB (Red Green Blue Technology). Obiettivo del lavoro e confrontare l’uso di scale colore tradizionali e spettrofotometri al fine di valutare la loro efficacia. Materiali e metodi E stata effettuata una revisione della letteratura utilizzando specifiche parole chiave e criteri di selezione per la scelta del colore in odontoiatria restaurativa. I risultati ottenuti sono stati poi analizzati. Risultati e discussione Nei vari lavori esaminati la scala guida cromatica riveste ancora un ruolo fondamentale come riferimento visivo, essendo utile sia all’inizio del trattamento sia per il controllo finale del risultato. Conclusioni Nei limiti della letteratura esaminata, la percezione del colore e la valutazione finale della qualita del prodotto si basano, sia per l’operatore sia per il paziente, sulla valutazione visiva. Benche quest’ultima sia ancora il gold standard, puo essere utile associarvi la tecnologia spettrofotometrica digitale per coadiuvare la scelta del colore piu corretta.

Strengths and Limitations of the Evidence-Based Movement Aimed to Improve Clinical Outcomes in Dentistry and Oral Surgery

Evidence-based medicine (EBM) is a scientific movement that originated from the idea of the English epidemiologist Archie Cochrane in 1970. However, only in the 90s, the “EBM” first appeared in the medical literature. The main purpose of EBM was to base clinical decision on evidence produced by clinical research rather than on the authority of expert clinicians. This purpose was pursued by integrating the rigorousness and validity of scientific method with the clinical observation of biological events. To formulate clinical recommendations on a particular clinical problem, exhaustive reviews of the current literature are performed, and relevant scientific papers are scored according to the quality of clinical research. For this purpose, the methodology employed (study design, generalizability of results, follow-up, and power of study) is evaluated according to standardized criteria: the best evidence comes from systematic reviews of clinical trials. Also in the field of dentistry, evidence-based (EB) movement was born in order to seek the “best available research evidence.” But evidence is not measurable in the same way in different medical disciplines: in particular, while drug effect is rather independent from clinician’s characteristics, the effectiveness of surgical procedures is strictly related to surgeon’s expertise, which is rather difficult to quantify. The research problems of dentistry have a lot in common with other surgical fields where at the moment the best quality of clinical outcomes originates from an integration of EBM and data from consensus conferences. A recently developed new approach to combine clinical evidence with experts’ opinion is the GRADE system, where GRADE stands for “Grades of Recommendation, Assessment, Development and Evaluation.”