Nadim Oliva

Accurate patient-specific modeling and finite element analysis are fundamental for achieving reliable results that can support pre-surgical planning, device design and biomechanical evaluation in oral surgery. This study presents a workflow for image-based patient-specific modeling applied to a guided bone regeneration clinical case. The workflow starts with image-based properties modeling, including bone density calibration, clinical image segmentation, and micro-mechanical bone modeling. Then, a custom device was designed, and a material was selected and its material properties were obtained through mechanical characterization. Lastly, a patient-specific finite element model was created with appropriate boundary conditions to evaluate the biomechanical behavior of the device and the bone state at interfaces with the device and screws. The work highlights the importance of bone density calibration and the modeling of anisotropic and nonhomogeneous bone properties in FEM to accurately evaluate the bone state after a guided bone regeneration surgery. This study has established a methodology for creating patient-specific models based on clinical imaging data in the context of oral surgery. This approach facilitates the biomechanical assessment of 3D-printed devices, as well as the interactions at the interfaces between device and bone, and screws and bone.

Immediate implant placement (IIP) has shown predictable outcomes when specific requirements are met. The aim of the present study was to radiographically evaluate the dimensions of mandibular incisors and the alveolar bone to further determine the feasibility of IIP in this area. A total of 404 intact mandibular incisor CBCT images from 101 patients (42 males, 59 females; mean age 49 ± 16.84 years) were analyzed. The mesiodistal tooth width and the distance between the incisal edge (IE), cementoenamel junction (CEJ), facial bone crest (BC), root apex (RA), and fenestration point (F) were registered, together with the alveolar bone width at 1 and 3 mm below BC. Finally, the angular discrepancy between the dental and the alveolar bone long axis (BLA) was recorded as the tooth torque (TT). The CEJ to BC distance was 3.23 ± 1.67 mm. The RA to F mean distance was 15.02 ± 3.97 mm. The mean alveolar bone buccolingual widths at 1 and 3 mm below the facial BC were 7.12 ± 0.82 and 6.32 ± 0.71 mm in the lateral and central incisors, respectively (P 0.001). The buccolingual width was less than 6 mm in more than 33% of the central incisors, but only in 3% of the lateral incisors, displaying increased alveolar width. The average was 165.66 ± 7.47 degrees. The results presented in this study point toward the need for careful consideration of the requirements for anterior mandibular IIP for success and predictability purposes.

Objective The primary objective of this review is to compare autogenous soft tissue grafts (connective tissue graft – CTG and free gingival graft—FGG) with different type of matrices (acellular dermal matrix—ADM, xenograft collagen matrix—XCM, volume-stable collagen matrix—VCMX) used to increase peri-implant soft tissues. Materials and methods A search on electronic databases was performed to identify randomized and non-randomized controlled trials (RCTs and CCTs, respectively) with either parallel or split-mouth design, and treating ≥ 10 patients. A network meta-analysis (NMA) was used to compare different matrices. Soft tissue thickness dimensional changes and keratinized width (KMW) changes were the primary outcome measures. The secondary outcomes were to evaluate: a) PROMs; b) volumetric changes; c) surgical operating time; and d) different periodontal measurements. Results A total of 23 studies were included in the qualitative analysis, and 16 studies (11 RCTs and 5 CCTs) in the quantitative analysis. A total of N = 573 sites were evaluated for NMA. CTG resulted the best material for increasing peri-implant soft tissue thickness, at 180 and 360 days after surgery. The use of an ADM showed good results for buccal thickness increase, primarily in the first three months after surgery. Vestibuloplasty + FGG resulted in the most effective technique for peri-implant KMW augmentation, after 180 days. Conclusions While CTG demonstrated better performance in all the comparison and FGG showed to be the best graft to increase keratinized mucosa up to 90 days, ADM and VCMX may be used to increase soft tissue horizontal thickness with lower patients’ morbidity. Limitations The limits of this NMA are the following: a) limited number of included studies; b) high heterogeneity among them (number of patients, treatment sites, surgical techniques, outcome measures, and follow-ups). Clinical Relevance Many studies compared the efficacy of autogenous and non-autogenous grafts in terms of gingival thickness, volume, and keratinized width increase. However, there is still not clear overall evidence on this topic. This NMA helps clinicians to choose the right material in different peri-implant soft tissue procedures. Recommendations for future studies are mandatory.

Dental fusion is defined as an abnormality in tooth shape caused by developmental tooth disturbances that produce an intimate union of dental tissues. This case report discusses treatment of a mandibular impacted "double" third molar in a 21-year-old patient that could have been related to either gemination or tooth fusion. Radiological examination allowed for careful analysis of the tooth's shape and root development, relation to the inferior alveolar nerve, and 3-dimensional position. After evaluation of therapeutic options and risks, and with the patient's consent, the authors opted to extract the tooth in question. Such favorable conditions as the incomplete development of the roots and the relatively young age of the patient, combined with the use of an antibiotic and antiseptic prophylaxis as well as a standard surgical approach, enabled a successful result to be achieved with no related complications.

The autotransplantation of a third molar represents an alternative treatment solution for filling an edentulous space that may exist because of traumatic avulsion, agenesis, large carious processes, or other reasons, particularly in young patients. Autotransplantation can offer many benefits, including maintenance of a normally functioning periodontium, preservation of pulp vitality, and completion of root formation. This case report describes a successful autotransplantation of an open-apex maxillary third molar germ to replace a hopeless mandibular first molar in a growing patient. After 24 months of follow-up, the donor tooth showed physiological mobility, absence of infection and ankylosis, positive pulp vitality, and fully formed periodontal integration. Radiographic examination confirmed a remarkable radicular edification.

OBJECTIVES Cysts are composed of an inner epithelial portion containing a liquid secretion and of an outer connective wall. In 2017, the last World Health Organization (WHO) classification of odontogenic and maxillofacial bone tumors was published. Odontogenic and non-odontogenic cysts were classified in two main groups: odontogenic cysts of inflammatory origin; odontogenic and non-odontogenic developmental cysts. In particular, nasopalatine duct cyst (NDC) is included among non-odontogenic developmental cysts and it is the most common cyst in this group. This article describes a case report of NDC treated at the authors' department concerning the most up to date clinical and epidemiological features. MATERIALS AND METHODS During April 2019, a 45 years patient was surgically treated for a nasopalatine duct cyst (NDC) of 2.3 cm. Clinical exam showed a palatal swelling elastic in consistency. Nevertheless, the patient was asymptomatic. All the four superior incisors were assessed through dental pulp test and the response was positive. Diagnostic hypothesis of nasopalatine duct cyst was formulated after having analyzed carefully both the first-level (orthopantomography) and the second-level (cone beam computed tomography) radiological exams. Then, surgical removal of the cyst was planned and these following steps were performed: local infiltration anesthesia, intrasulcular incision, full-thickness flap, mucoperiosteum detachment, access to the surgical site with straight handpiece and carbide bur, removal of the cyst and alveolar curettage. In conclusion, a primary healing was achieved performing simple interrupted stitches using a 4/0 polyglycolic acid suture. The patient was discharged after having provided him post-operative instructions and pharmacological therapy. In particular, antiseptic mouth rinse and anti-inflammatory drugs were prescribed. The sample was sent to anatomy pathology department to confirm the diagnosis. Clinical and radiological follow-up were at 1, 3, 6 and 12 months. RESULTS Histopathological examination confirmed the diagnosis of NDC. Macroscopically, the biopsy specimen appeared as a thin grey lesion. With a maximum dimension (diameter) of 2.3 cm. From the microscopic point of view, the examinated sample was characterized by a paucistratified architecture formed by cubic cells, some with "terminal plate" structure. Clinical and radiographic follow-up showed an increasing and full regeneration of both soft and hard tissues. Neither intra-operatory nor post-operatory complications were detected. CONCLUSIONS Surgical removal of NDC is the gold standard treatment. The literature reported a recurrence rate that ranged from 0% to 11%. It can't be made NDC diagnosis without histopathological examination. CLINICAL SIGNIFICANCE Although nasopalatine duct cyst is characterized by a low incidence, it is one of the most common developmental cysts. Therefore, the knowledge of diagnostic features and gold standard treatment allows clinicians to treat it correctly.