Sinus Lift and Implant Insertion on 3D-Printed Polymeric Maxillary Models: Ex Vivo Training for In Vivo Surgical Procedures.

BACKGROUND AND OBJECTIVES: The aim of this study is to demonstrate the increased efficiency achieved by dental practitioners when carrying out an ex vivo training process on 3D-printed maxillaries before performing in vivo surgery. MATERIALS AND METHODS: This developed ex vivo procedure comprises the following phases: (i) scanning the area of interest for surgery; (ii) obtaining a 3D virtual model of this area using Cone Beam Computed Tomography (CBCT); (iii) obtaining a 3D-printed model (based on the virtual one), on which (iv) the dental practitioner simulates/rehearses ex vivo (most of) the surgery protocol; (v) assess with a new CBCT the 3D model after simulation. The technical steps of sinus augmentation and implant insertion could be performed on the corresponding 3D-printed hemi-maxillaries prior to the real in vivo surgery. Two study groups were considered, with forty patients divided as follows: Group 1 comprises twenty patients on which the developed simulation and rehearsal procedure was applied; Group 2 is a control one which comprises twenty patients on which similar surgery was performed without this procedure (considered in order to compare operative times without and with rehearsals). RESULTS: Following the ex vivo training/rehearsal, an optimal surgery protocol was developed for each considered case. The results of the surgery on patients were compared with the results obtained after rehearsals on 3D-printed models. The performed quantitative assessment proved that, using the proposed training procedure, the results of the in vivo surgery are not significantly different (p = 0.089) with regard to the ex vivo simulation for both the mezio-distal position of the implant and the distance from the ridge margin to sinus window. On the contrary, the operative time of Group 1 was reduced significantly (p = 0.001), with an average of 20% with regard to in vivo procedures performed without rehearsals (on the control Group 2). CONCLUSIONS: The study demonstrated that the use of 3D-printed models can be beneficial to dental surgeon practitioners, as well as to students who must be trained before performing clinical treatments.

Complementarity of Photo-Biomodulation, Surgical Treatment, and Antibiotherapy for Medication-Related Osteonecrosis of the Jaws (MRONJ).

Background and Objectives: Antiresorptive or anti-angiogenic agents may induce medication-related osteonecrosis of the jaws (MRONJ), which represents a challenge for clinicians. The aim of this study is to design and apply a composed and stage-approach therapy combining antibiotherapy, surgical treatment, and photo-biomodulation (PBM) for the prevention or treatment of MRONJ lesions. Materials and Methods: The proposed treatment protocol was carried out in the Department of Oral & Maxillofacial Surgery of the "Victor Babes" University of Medicine and Farmacy of Timisoara, in 2018-2020. A total of 241 patients who were previously exposed to antiresorptive or anti-angiogenic therapy, as well as patients already diagnosed with MRONJ at different stages of the disease were treated. A preventive protocol was applied for patients in an "at risk" stage. Patients in more advanced stages received a complex treatment. Results: The healing proved to be complete, with spontaneous bone coverage in all the n = 84 cases placed in an "at risk" stage. For the n = 49 patients belonging to stage 0, pain reductions and decreases of mucosal inflammations were also obtained in all cases. For the n = 108 patients proposed for surgery (i.e., in stages 1, 2, or 3 of MRONJ), a total healing rate of 91.66% was obtained after the first surgery, while considering the downscaling to stage 1 as a treatment "success", only one "failure" was reported. This brings the overall "success" rate to 96.68% for a complete healing, and to 99.59% when downscaling to stage 1 is included in the healing rate. Conclusions: Therefore, the clinical outcome of the present study indicates that patients with MRONJ in almost all stages of the disease can benefit from such a proposed association of methods, with superior clinical results compared to classical therapies.

Contribution of the cyto-histopathological diagnosis and ultrastructural parameters to the evaluation of maxillary cysts - a 10-year multidisciplinary approach.

Diagnostic and treatment plans in cystic jawbone tumors are often difficult to address. The etiopathogenic links involved in cell-matrix differentiation disorders are complex. Quantification of the inflammatory process in the evolution of cystic odontogenic lesions highlights a particular reactivity of the host, especially age-dependent and the endodontic-periodontal space interrelation, drawing attention to the difficulties of etiopathogenic, evolution, prognostic and treatment of these lesions. Difficulties in histopathological (HP) diagnosis are reported by the lack of morphofunctional integration of dental tissues, both topographically and evolutionarily, especially when odontogenic epithelial remains in the cystic wall, reactive bone condition, appearance and condition of the reactive epithelium are overlooked. In this study, we developed an interdisciplinary approach for the dynamics of tissue morphology found in the walls of maxillary cysts. Failure to recognize the tissues that form the cystic lesion leads to misinterpretations of pathology and to the wrong classification in the group of maxillary cysts. We analyzed by different techniques 564 biopsy fragments from maxillary cystic lesions, most of which are clinically classified as inflammatory or odontogenic ones. From our experience, we reevaluated the lesions with cystic changes and completed the diagnosis in 10-12% of cases. The most common maxillary cystic lesion encountered by us was the root cyst, an inflammatory dental cyst, which has been over diagnosed clinically, radiologically and histopathologically. Recognition and selection of embryonic remnants from odontogenesis is crucial for the HP diagnosis of maxillary cysts, allowing the clinician to monitor treatment or to develop evolutionary-prognostic perspectives of odontogenic cystic lesions.

Alveolus soft and bone tissue regeneration after laser biomodulation - a histological study.

Functional and esthetic recovery of the patient after tooth extraction is a concern in the nowadays-dental medicine. Immediate implant placement in fresh sockets in posterior sides of the jaws is difficult because of the high amount of bone loss and the disparity between the diameter of the alveolus and the implant. The objective is to evaluate the effect of laser biomodulation alveolar socket healing process of healthy patients. A number of 36 molars have been extracted due to advanced caries lesions from the same dental arch but on opposite sites. Laser irradiation was performed on one side after extraction; the other side was used as control. An Epic-X laser diode (Biolase) Indium-Gallium-Arsenide-Phosphorus (In-Ga-As-P) 940 nm was used in a continuous mode, 0.9 W, 36 J for 80 seconds, daily exposure, in the first seven days after extraction. Specimens of soft and hard tissue were surgically incised and removed by a 4.4 mm diameter trepan from the extraction sites, eight weeks after the surgical procedure. The specimens were prepared by use of two staining procedures: Hematoxylin-Eosin (HE) and Mallory's trichrome. The prepared slides were examined under Leica DM750 optical microscope, 5× and 10× magnification. Laser biomodulation therapy accelerates bone formation by increasing osteoblastic activity. The histological study demonstrates early new bone formation, the regeneration effects in fresh intact bony alveolus compared with the soft and bone regeneration level of non-treated fresh alveolus. Laser biomodulation therapy accelerates soft tissue regeneration and bone formation.