L'ipossia è una condizione patologica determinata da un ridotto apporto di ossigeno a livello tissutale. A partire dagli anni '60, Tomlinson e Gray hanno dimostrato la presenza di regioni di scarsa ossigenazione nel cancro del polmone e hanno osservato che questa caratteristica del microambiente tumorale è associata ad una maggiore resistenza alla radioterapia. La determinazione dell'ipossia nei tumori è pertanto della massima rilevanza clinica, in quanto l'aggressività del tumore, la deriva metastatica, il mancato controllo della neoplasia, l'aumento del rischio di recidiva e, in definitiva l'esito sfavorevole sono associati all'ipossia. Negli ultimi decenni, c'è stato un crescente interesse nello sviluppo di metodi per la valutazione dell'ossigenazione tumorale. Questi metodi possono essere invasivi, come il sensore polarografico di O2, o non invasivi, basati principalmente sulle tecniche di imaging. Le modalità di imaging sono senza dubbio le più interessanti perché garantiscono una visualizzazione onnicomprensiva del tessuto patologico e sono in grado di identificare il fenomeno anche in luoghi inaccessibili alle procedure invasive. Tra le modalità di imaging per la valutazione dell'ipossia, la tomografia ad emissione di positroni (PET) è una delle più studiate, in quanto offre: (a) ampio assortimento di radiofarmaci; (B) buona risoluzione intrinseca; (C) rappresentazione tridimensionale (3D); (D) (semi)quantificazione; (E) maggiore facilità per il paziente, e (f) riproducibilità dei dati. L'oggetto della tesi attuale è quello di studiare il ruolo dell'imaging molecolare alla PET nell'ipossia tumorale. Il testo è diviso in quattro sessioni distinte incentrate nel fornire in primis una panoramica sui radiofarmaci principali (Sessione-1), poi nella valutazione della correlazione tra l'espressione tissutale d'ipossia e l'imaging alla 18F-FDG PET/TC (Sessione-2). Le altre due sessioni analizzano l'impatto prognostico del tracciante per l'ipossia (64Cu-ATSM) nei tumori solidi (Sessione-3), seguito da una sofisticata analisi frattale di confronto fra le acquisizioni precoci e tardive alla 64Cu ATSM PET/TC nei tumori solidi (Sessione-4). / Hypoxia is a pathological condition caused by a reduced oxygen supply at the tissue level. Since the 60’s, Tomlinson and Gray have demonstrated the presence of regions of poor oxygenation in lung cancer, and noted that this characteristic of tumor microenvironment is associated to increased resistance to radiotherapy. The detection of hypoxia in tumors is therefore of utmost clinical relevance, because tumor aggressiveness, metastatic drift, failure to disease control, increased risk of recurrence and ultimately poor outcome are associated with hypoxia. In recent decades, there has been an increasing interest in developing methods for the assessment of tumor oxygenation. These methods can be invasive, such as the polarographic O2-sensor, or non-invasive, mainly based on imaging techniques. Imaging modalities are undoubtedly the most appealing techniques for this purpose, because they guarantee an all-encompassing visualization of the pathological tissue and can identify the phenomenon even at sites inaccessible to invasive procedures. Among the image-based modalities for hypoxia assessment, positron emission tomography (PET) is one of the most extensively investigated, because it offers: (a) broad assortment of radiopharmaceuticals; (b) good intrinsic resolution; (c) three-dimensional (3D) tumor representation; (d) (semi)quantification of the hypoxic burden; (e) patient friendliness, and (f) reproducibility. The object of the current thesis is to investigate the role of molecular imaging with PET in cancer hypoxia. The text is divided into four different sessions focused on giving at first an insight on principal radiopharmaceuticals applied for hypoxia imaging (Session-1), then concentrating on the correlation of tissue expression of hypoxia and imaging findings on 18F-FDG PET/CT (Session-2). The next two sessions will analyze the prognostic impact of the hypoxia-specific tracer (64Cu-ATSM) in solid tumors (Session-3), followed by a sophisticated ad hoc computer-aided fractal geometry based analysis of DICOM images for early and late acquisitions on 64Cu-ATSM PET/CT in solid tumors (Session-4).

Background: An increasing number of studies have established that circulating tumor cells (CTCs) are a heterogeneous population in which cells have different degrees of metastatic potential mainly due to epithelial-mesenchymal transition (EMT). This study aimed to assess the feasibility of circulating esophageal cancer cells identification, characterization and to evaluate their prognostic value in esophageal cancer Methods: In order to closely mimic CTC heterogeneity, MC10A and HMEL cell lines differently forced in EMT are used. Single cell analysis was conducted by DEPArray. We assigned a specific phenotypic tag to each potential CTC population: Epithelial-tag, Mesenchymal/stem-tag. We evaluated the basal cell phenotype and after EMT induction. Subsequently, the Grab all assay was performed on peripheral blood samples from patients with esophageal cancer. This feasibility study enrolled 11 patients (4 M1, 7 M0). Analyses were conducted on 3 peripheral blood samples (15/20 ml) per patients. Blood samples from non-metastatic patients were taken before and after primary neo-adjuvant therapy and after secondary treatment (surgery). Samples from metastatic patients were taken before and after first line therapy and after second line therapy. CTCs were identified and sorted singly by DEPArray system. Results: The assay was able to detect the phenotypic changes in cell lines mimicking CTC heterogeneity. Before therapy, CTCs were found in 3/4 metastatic patients. Of the 7 non-metastatic patients, 3 were positive for CTCs before therapy. Examining CTC status at different clinical time points, it was possible to suggest a correlation between the presence of CTCs and disease progression. Conclusions: Data showed that the assay is feasible, capable to analyze the phenotypic tags by DEPArray using a multiple staining without aspecific signals. Experiments carried out from both metastatic/non metastatic cancer patients showed the ability of the Grab-allassay to identify subpopulations of CTCs with different epithelial/stem/mesenchymal or hybrid phenotypes potentially related to disease progression.

Nowadays video-assisted lobectomy could be considered an appropriate treatment option for early stage lung cancer patients, as obtaining similar or even better early outcomes when compared to open standard lobectomy. This study was aimed at verifying the long-term impact (three months after surgery) of VATS-lobectomy technique on physical and mental status of patients undergoing lung resection for lung cancer and to compare the physical variation to the one registered after open approach. We enrolled patients treated by VATS-lobectomy at our institution since June 2012 to June 2015, comparing the preoperative physical evaluation (in terms of FEV1, DLCO and VO2max) and perceived quality of life (measured using the EORTC questionnaire) to the postoperative values. Moreover we performed a propensity score matching analysis to verify if the physical variation registered after VATS-lobectomy differed from that after open resection. We found a three months postoperative reduction of the physical indicators in comparison to the preoperative values (FEV1-variation: -8.3%, DLCO-variation: -12.4%, VO2max-variation: -6.6%). A similar negative trend was found for the psychological indicators, but the only parameter with a significative worsening was the perceived physical functioning (variation: -6.2%). The propensity score procedure yielded 83 well-matched open and VATS-lobectomy patients. The reductions in FEV1, DLCO and VO2max were similar in both groups (open patients’ reduction: FEV1 -10%, DLCO -11.9%, VO2max -5.5%; VATS patients’ reduction: FEV1 -7.2%, DLCO -10.6%, VO2max -6.9%), with a Cohen effect size < 0.2 for all the comparisons. In conclusion, VATS-lobectomy influences a reduction of the preoperative functional status three months after the operation, without affecting the postoperative perceived quality of life. Moreover VATS-lobectomy doesn’t offer any advantage in terms of FEV1, DLCO and exercise capacity recovery in comparison to the open approach.

La chirurgia guidata dalle immagini(IGS) è usata in numerosi settori della chirurgia. Un innovativo sistema di navigazione chiamato Implanav è stato sviluppato dall'Università di Bologna insieme alla ditta BresMedical per consentire al chirurgo di monitorare in tempo reale le strutture anatomiche, durante il posizionamento degli impianti in campo maxillo-facciale. L'obbiettivo dello studio è di valutare in vitro ed in vivo le potenzialità e la precisione di questo sistema. / Image-Guided Surgery (IGS) is used in a variety of medical procedures. An innovative system called ImplaNav has been developed by University of Bologna and BresMedical for oral and maxillofacial surgical navigation, in order to generate three-dimensional volumetric representations of the maxillofacial area, which allow surgeons to evaluate a patient's anatomy before surgery and assist in planning for the placement of implants in appropriate , ideal or preferred positions. The objective of this study is to evaluate the accuracy of the ImplaNavTM software and registration tools by presenting results obtained deploying the system in-vitro and in-vivo cases. The investigation focuses on how the surgical guidance, by way of visualization of a surgeon's instrument via optical tracking offered by the ImplaNavTM system, generates an immediate feedback on the possible misplacement or positioning of a dental implant.

La chirurgia della trachea è sempre stata una sfida per il chirurgo in considerazione delle notevoli difficoltà nel ripristinare la anatomia e la funzione dell’organo. Attualmente il trapianto di trachea umano rivascolarizzato non è stato ancora realizzato, principalmente a causa della mancanza di un peduncolo vascolare tracheale noto. Nel 2008 l’otorinolaringoiatra belga Paul Delaere ha descritto una tecnica di trapianto di trachea da cadavere mediante il confezionamento di un lembo composito. Il lembo antibrachiale utilizzato è una ottima alternativa, ma oggi sono più utilizzati i lembi perforanti rispetto ai lembi assiali, in base a una serie di vantaggi ben noti. La possibilità di utilizzare il lembo perforante anterolaterale di coscia al posto del lembo “cinese” come base per il trapianto composito sfrutta i vantaggi di questo tipo di lembo. Nello studio è stata valutata la fattibilità tecnica del lembo composito mediante una valutazione anatomica su cadavere. / Trachea surgery has always been a challenge for the surgeon in view of remarkable difficulty in restoring the anatomy and the function. Currently revascularized human trachea transplantation is not possible due to the lack of a single vascular pedicle. In 2008 Paul Delaere described a tracheal transplantation technique using a cadaveric donor. The chinese flap used by Delaere to harvest the compiste flap is a good alternative, but today perforator flaps represent a better choice. The possibility to use the anterolateral thigh perforator flap in place of the chinese flap was studied on cadavers in the present stduy.

Oggetto della tesi e' l'approfondimento su tecniche e metodiche di preservazione del polmone isolato per lo studio ecografico. E' discussa l'appropriatezza sull'uso degli ultrasuoni in corso di chirurgia mini invasiva polmonare, obiettivo di una ricerca sperimentale. Il razionale dello studio si fonda sull'indicazione all'exeresi chirurgica di noduli polmonari di diametro inferiore al centometro, ovvero di diametro superiore ma localizzati in aree centrali del polmone. Queste lesioni sono sempre piu' frequentente diagnosticate per mezzo di avanzate tecniche di imaging. L'atto chirurgico ha scopo terapeutico quando sia stata posta la diagnosi di neoplasia maligna, diagnostico-terapeutico quando non sia ancora ottenuta la tipizzazione istologica della lesione. La tecnica toracoscopica offre numerosi vantaggi rispetto alle tecniche chirurgiche tradizionali ma presenta il grave limite di non permettere la palpazione diretta del tessuto polmonare e la localizzazione della formazione tumorale quando essa non sia visibile macroscopicamente. Gli ultrasuoni sono stati utilizzati con successo per indirizzare la localizzazione del nodulo polmonare. Scopo dello studio sperimentale e' quello di confrontare tecniche diverse di preservazione del polmone isolato in un modello animale, comparando catatteristiche e prestazioni di sonde ecografiche differenti per tipologia. Del tutto recentemente, in ambito trapiantologico, sono state proposte tecniche di preservazione organica utili ai fini di uno studio anatomico sperimentale particolareggiato (EVLP) e moderna e' da considerarsi la concezione di mezzi tecnici specifici per la localizzazione di bersagli intrapolmonari. La tecnica clinica applicata allo studio del particolare ecografico, nel modello animale, ha reso comprensibile e meglio definito il ruolo delle sonde ecografiche nell'individuazione di forme tumorali suscettibili di exeresi definitiva. / The primary focus of this dissertation is research about techniques and methods of isolated lung tissue preservation for sonographic investigation. Doctoral thedis describes the use of ultrasound probes in an experimental model and its clinical application during minimally invasive pulmonary surgery. The rationale of the study is based on the indication to surgical procedure and when is clinically in the treatment of solitary pulmonary nodules (<1 cm or greater but more central in visible appearance). In the era of CT screening programs, these lesions are more frequently diagnosed with advanced imaging techniques. Surgical procedure is therapeutic when a diagnosis of malignancy is obtained, but also diagnostic if we must correct the technique to the histologic pattern or ascertain pathological growth of the lesion. Thoracoscopic techniques offers several advantages over traditional "open" procedures but shows clinical limits. These mininimally invasive approaches do not allow to direct handling of tumor when is not macroscopically visible. Ultrasound have been successfully used to guide localization of pulmonary nodules. The experimental study compare different techniques of lung tissue preservation in a porcine model, the proceed to analysis of diagnostic performances related to a panel of echographic probes. More recently, a number of different techniques, adopted in lung transplantation programs, has been considered as useful for experimental anatomical study (EVLP) and several instruments of scientific research has been comceived for intrapulmomary localization of neoplastic lesions. These clinical techniques were originally applied in an animal porcine model, studied for scientific purpose, and described in a personal review of cases. Results of surgical interesr were related to scientific Literature in order to identify the possible role of echographic probes on clinical context.

La Valvola Aortica Bicuspide (BAV) rappresenta la più comune anomalia cardiaca congenita, con un’incidenza dello 0,5%-2% nella popolazione generale. Si caratterizza per la presenza di due cuspidi valvolari anziché tre e comprende diverse forme. La BAV è frequentemente associata agli aneurismi dell’aorta toracica (TAA). La dilatazione dell’aorta espone al rischio di sviluppare le complicanze aortiche acute. Materiali e metodi Sono stati reclutati 20 probandi consecutivi sottoposti a chirurgia della valvola aortica e dell'aorta ascendente presso l'Unità di Chirurgia Cardiaca di Policlinico S.Orsola-Malpighi di TAA associata a BAV. Sono stati esclusi individui con una condizione sindromica predisponente l’aneurisma aortico. Ciascun familiare maggiorenne di primo grado è stato arruolato nello studio. L’analisi di mutazioni dell’intero gene ACTA2 è stata eseguita con la tecnica del “bidirectional direct sequencing”. Nelle forme familiari, l’intera porzione codificante del genoma è stata eseguita usando l’exome sequencing. Risultati Dopo il sequenziamento di tutti i 20 esoni e giunzioni di splicing di ACTA2 nei 20 probandi, non è stata individuata alcuna mutazione. Settantasette familiari di primo grado sono stati arruolati. Sono state identificate cinque forme familiari. In una famiglia è stata trovata una mutazione del gene MYH11 non ritenuta patogenetica. Conclusioni La mancanza di mutazioni, sia nelle forme sporadiche sia in quelle familiari, ci suggerisce che questo gene non è coinvolto nello sviluppo della BAV e TAA e, l’associazione che è stata riportata deve essere considerata occasionale. L’architettura genetica della BAV verosimilmente dovrebbe consistere in svariate differenti varianti genetiche che interagiscono in maniera additiva nel determinare un aumento del rischio. / The bicuspid aortic valve (BAV) is the most common congenital cardiac abnormality, with an incidence of 0.5% -2% in the general population. BAV is characterized by the presence of two valve cusps rather than three, and includes various forms. BAV is frequently associated with thoracic aorta aneurysms (TAA).The pathological dilatation of the aorta exposes these patients at risk of acute aortic complications associated with aneurysms, including dissection or rupture. Materials and methods We recruited 20 consecutive probands who underwent surgery of the aortic valve and ascending aorta at the Cardiac Surgery Unit of Policlinico S.Orsola-Malpighi for TAA associated with BAV, and who had their first degree relatives available. Individuals with a syndromic condition predisposing to aortic aneurysm were excluded. Each first degree family member (age> 18 years old) was recruited. Mutational analysis of the entire ACTA2 gene by bidirectional direct sequencing of amplified genomic DNA fragment with intron-based was performed. In the familiar forms, the entire coding portion of the genoma was done using the exome sequencing. Results After sequencing all 20 exons and splice junctions of ACTA2 in our 20 probands, no mutation was detected.Seventy-seven first-degree familiar members were enrolled in our study.Five familiar cases are identified: 2 of these underwent surgery for BAV and one for BAV+TAA.In one family we found a mutation on MYH11 gene but it was considered not pathogenic. Conclusion The lack of ACTA2 mutations, both in sporadic and in familiar forms, suggests that this gene is not involved in the development of BAV and TAA and their association, which was reported, has to be considerate occasional. In conclusion, the genetic architecture of the BAV would likely consist of several genetic variants that interact in an additive in determining an increased risk of development of BAV and dilatation of the thoracic aorta.

OBIETTIVO : Quantificare le CECs/ml nei pazienti affetti da ischemia critica (IC) degli arti inferiori, eventuali correlazioni tra i fattori di rischio, lo stadio clinico con l’ aumento delle CECs. Valutare i cambiamenti strutturali (calcificazione ed infiltratto infiammatorio) e l’ angiogenesi (numero di capillari /sezione) della parete arteriosa. MATERIALI E METODI: Da Maggio 2006 ad Aprile 2008 in modo prospettico abbiamo arruolato paziente affetti da IC da sottoporre ad intervento chirurgico. In un data base abbiamo raccolto : caratteristiche demografiche, fattori di rischio, stadiazione dell'IC secondo Leriche-Fontaine (L-F), il tipo di intervento chirurgico. Per ogni paziente abbiamo effettuato un prelievo ematico di 2 ml per la quantificazione immunomagnetica delle CECs e prelievo di parete arteriosa. RISULTATI: In modo consecutivo abbiamo arruolato 33 pazienti (75.8% maschi) con età media di 71 aa (range 34-91aa), affetti da arteriopatia ostruttiva cronica periferica al IV stadio di L-F nel 84.8%, da cardiopatia ischemica cronica nel 60.6%, da ipertensione arteriosa nel 72.7% e da diabete mellito di II tipo nel 66.6%. Il valore medio di CECs/ml è risultato significativamente più elevato (p= 0.001) nei soggetti affetti da IC (CECs/ml =531.24 range 107- 3330) rispetto ai casi controllo (CECs/ml = 125.8 range 19-346 ). Le CECs/ml nei pazienti diabetici sono maggiori rispetto alle CECs/ml nei pazienti non diabetici ( 726.7 /ml vs 325.5/ml ), p< 0.05 I pazienti diabetici hanno presentato maggior incidenza di lesioni arteriose complesse rispetto ai non diabetici (66% vs 47%) e minor densità capillare (65% vs 87%). Conclusioni : Le CECs sono un marker sierologico attendibile di danno vascolare parietale, la loro quantità è maggiore nei pazienti diabetici e ipertesi. La minor capacità angiogenetica della parete arteriosa in presenza di maggior calcificazioni ed infiltrato infiammatorio nei diabetici, dimostra un danno istopatologico di parete maggiore . / OBJECTIVE: To quantify the number of circulating endothelial mature cells (EMC) in patients with critical limb ischemia (CI), and if correlations exit with risk factors, clinical stage and the number of cEMC. Evaluate the vascular structure changes (calcification and inflammatory infiltrate) and angiogenesis (number of capillary/arterial slice) of arterial wall. METHODS: Between 2006, may, and 2008, april, we’ve enrolled in a prospective study patients with CI scheduled for surgery. Demographic data, risk factors, clinical stage according to Leriche-Fontaine, type of surgery have been collected and stored in a database. For every patient 2 ml of blood have been sampled for immunomagnetic quantification of cEMC, so as a sample of the arterial wall. RESULTS: Thirtythree patients (25 males, 75,8%), aged 34-91, average 71years old, with CI underwent surgical revascularization have been enrolled. Twentyeight patients (84.8%) had a IV stage PAOD, chronic heart ischemia (60.6%), hypertension (72.7%) and diabetes mellitus type II (66.6%). The average concentration of cEMC/ml is significant higher (p=0.001) in patients with CI (cEMC=531.24, range 107-3330) than in control cases (cEMC =125.8, range 19-346). Also patients with diabetes type II have a higher concentration of cEMC than the non-diabetic patients (726.7/mm vs 325.5/ml vs.), with a p<0.05. Arterial wall of pts. with diabetes , compared with control group, revealed a higher incidence of complex arterial lesions (66% vs. 47%) and a lower capillary density (65% vs. 87%). CONCLUSION: cEMC are a reliable marker of vascular wall damage. Their concentration is higher in patients with diabetes, hypertensive disease. In patients with diabetes type 2 we’ve found a minor angiogenic capability with more calcifications and inflammatory infiltrate, showing a more serious damage

The aim of this PhD thesis " Simulation Guided Navigation in cranio- maxillo- facial surgery : a new approach to Improve intraoperative three-dimensional accuracy and reproducibility during surgery ." was at the center of its attention the various applications of a method introduced by our School in 2010 and has as its theme the increase of interest of reproducibility of surgical programs through methods that in whole or in part are using intraoperative navigation. It was introduced in Orthognathic Surgery Validation a new method for the interventions carried out according to the method Simulation Guided Navigation in facial deformities ; was then analyzed the method of three-dimensional control of the osteotomies through the use of templates and cutting of plates using the method precontoured CAD -CAM and laser sintering . It was finally proceeded to introduce the method of piezonavigated surgery in the various branches of maxillofacial surgery . These studies have been subjected to validation processes and the results are presented . / Obiettivo di questa tesi di Dottorato “Simulation Guided Navigation in cranio-maxillo-facial surgery: a new approach to improve intraoperative three-dimensional accuracy and reproducibility during surgery.” ha avuto al centro delle proprie attenzioni le varie applicazioni di una metodica introdotta dalla ns. Scuola nel 2010 e che ha come tema di interesse l’aumento delle riproducibilità dei programmi chirurgici mediante metodiche che in toto o in parte utilizzano il navigatore intraoperatorio. Si è introdotto in Chirurgia Ortognatica un nuovo Metodo di Validazione per gli interventi effettuati secondo la metodica Simulation Guided Navigation nelle malformazioni facciali ; si è poi analizzata la metodica di controllo tridimensionale delle osteotomie mediante l’utilizzo delle dime di taglio e delle placche premodellate mediante metodica CAD-CAM e sinterizzazione laser. Si è infine proceduto ad introdurre la metodica di chirurgia piezonavigata alle varie branche di chirurgia maxillo-facciale. Tali studi sono stati sottoposti a processi di validazione ed i risultati vengono presentati.

PURPOSE: The aim of this randomized clinical trial is to compare 2 different approaches for Guided Bone Regeneneration (GBR) in posterior region of atrophic mandibles regarding: I) the amount of vertical bone regeneration, II) the type and frequencies of surgical and healing complications, III) the implants primary stability and the osseointegration rate. MATERIAL AND METHODS: Forty partially edentulous patients with atrophic posterior mandible, who require a three-dimensional bone regeneration and an implant-prosthetic rehabilitation, were treated according the following protocol. Patients were randomly divided into two study group: 20 patients were treated with non-resorbable d-PTFE titanium-reinforced membranes (group A); and 20 patients with titanium mesh covered by cross-linked collagen membranes (group B). All patients received two or more double variable thread tapered implants and a mixture of autogenous bone and bone allograft according to one-stage GBR approach. In each group were evaluated the amount of vertical bone regeneration and the insertion torque value (IT) and implant stability quotient (ISQ) of all implants. In addition, all complications were analyzed, distinguishing between “surgical” and “healing” complications. RESULTS: The vertical bone regeneration was 4.3 ± 1.2 mm in the group A and 4.2 ± 1.1 in the group B. 99% of implants showed an optimal primary stability with insertion torque values > 35 Ncm and ISQ values > 60. All implants achieved a successful osseointegration. In the group A, surgical and healing complication rates were 5.0% and 15.9% respectively, In the group B, complication rates were 15.0% and 21.1% respectively. CONCLUSIONS: The preliminary results of this RCT suggested that both GBR approaches are predictability and effectiveness for the restoration of atrophic posterior mandible. Double variable thread tapered implants permitted to achieve an adequate primary stability in order to perform an one-stage GBR approach. / PURPOSE: The aim of this randomized clinical trial is to compare 2 different approaches for Guided Bone Regeneneration (GBR) in posterior region of atrophic mandibles regarding: I) the amount of vertical bone regeneration, II) the type and frequencies of surgical and healing complications, III) the implants primary stability and the osseointegration rate. MATERIAL AND METHODS: Forty partially edentulous patients with atrophic posterior mandible, who require a three-dimensional bone regeneration and an implant-prosthetic rehabilitation, were treated according the following protocol. Patients were randomly divided into two study group: 20 patients were treated with non-resorbable d-PTFE titanium-reinforced membranes (group A); and 20 patients with titanium mesh covered by cross-linked collagen membranes (group B). All patients received two or more double variable thread tapered implants and a mixture of autogenous bone and bone allograft according to one-stage GBR approach. In each group were evaluated the amount of vertical bone regeneration and the insertion torque value (IT) and implant stability quotient (ISQ) of all implants. In addition, all complications were analyzed, distinguishing between “surgical” and “healing” complications. RESULTS: The vertical bone regeneration was 4.3 ± 1.2 mm in the group A and 4.2 ± 1.1 in the group B. 99% of implants showed an optimal primary stability with insertion torque values > 35 Ncm and ISQ values > 60. All implants achieved a successful osseointegration. In the group A, surgical and healing complication rates were 5.0% and 15.9% respectively, In the group B, complication rates were 15.0% and 21.1% respectively. CONCLUSIONS: The preliminary results of this RCT suggested that both GBR approaches are predictability and effectiveness for the restoration of atrophic posterior mandible. Double variable thread tapered implants permitted to achieve an adequate primary stability in order to perform an one-stage GBR approach.