Mechanical pull-out test of a new hybrid fixture-abutment connection: an in vitro study

Implant abutment connection was described among the main causes of peri-implant bone resorption. The aim of this in vitro study was to test the coupling capacity, the surface modification of a new hybrid connection and the influence of repeated connection activations caused during the main clinical and laboratory phases. A total of 40 implant-abutment screw retained systems with 10 degrees-conical and internal hexagon connection were tested. The connection was screwed, fixed to the universal test machine, removed the screw and a pull-out test was performed. Test was repeated five times in succession. Also Scanning Electron Microscopy (SEM) was used to detect microscopically surface modification. Analysis of variance and Tukey tests were used for the statistical analysis. Pull-out test reveals a mean value of 131.35 +/- 16.52 Newton Centimeter (N center dot cm). For each single activation, results from first to fifth were: 113.9 +/- 13.02, 126.1 +/- 12.81, 138.11 +/- 15.15, 138.8 +/- 11.90 and 140 +/- 12.99 N center dot cm. A statistically significant difference between the measurements and an increase in the removal force was shown. The collected data supports the use of this new type of connection, resulting in a very strong interface between implant and abutment. Also, repeated activation of connection can promote a better coupling of the implant-abutment interface

MANDIBLE BROWN TUMOR CAUSED BY PRIMARY HYPERPARATHYROIDISM

Brown tumor is a uni or multi-focal bone lesion, which represents the terminal stage of the hyperparathyroidism-dependent bone pathology. It often appears as an expansive osteolytic lesion of the bone, commonly in the mandible, ribs, pelvis and femur. A 56 year-old male patient presented with an asymptomatic unilocular radiolucent lesion of the right mandible without teeth. The lesion had a diameter of about 3 cm, had sharply delimited margins and was surrounded by an osteosclerotic rim. Under local anesthesia, the lesion was extracted surgically. The microscopic diagnosis was brown tumor of the mandible. The following report describes a patient with secondary hyperparathyroidism who developed a brown tumor of the mandible, discuss the differential diagnosis, and review the literatur

The Effects of High Insertion Torque Versus Low Insertion Torque on Marginal Bone Resorption and Implant Failure Rates: A Systematic Review With Meta-Analyses

OBJECTIVES: The aim was to analyze the data about the effects on marginal bone resorption and implant failure rates between implants inserted with high or low insertion torque values. MATERIALS AND METHODS: A systematic literature search until July 2015 was conducted. Data were summarized qualitatively in descriptive tables and quantitatively by performing random effects meta-analyses of effect sizes (ESs) for bone resorption and bone-to-implant contact (BIC) and relative risks (RRs) for implant failures. Risk of bias assessments were performed using the Cochrane tool for human studies and the SYRCLE's tool for animal studies. RESULTS: Four studies in humans and 6 quasirandomized animal studies were included. A total of 591 implants were evaluated qualitatively: 348 installed with high insertion torque (>25 Ncm, up to 176 Ncm) and 243 implants inserted with low torque values (<30-35 Ncm). No significant differences were detected for bone resorption (ES, 0.13; 95% confidence interval [CI], -0.12 to 0.38 in human studies; ES predictive interval from 35.03 to 34.50 in animal studies), implant failure (RR, 0.39; 95% CI, 0.01-20.77 in human studies; RR, 2.05; 95% CI, 0.19-21.71 in animal studies), or BIC (ES predictive interval from -3.84 to 5.13 in animal studies). CONCLUSION: The current review indicated that there is no significant difference in marginal bone resorption and implant failure rate between implants inserted with high or low insertion torque values

A TECHNIQUE FOR AN ACCELERATED RIGID SPLINTING OF MULTIPLE IMPLANTS FOR IMMEDIATE LOADING

Different protocols have been developed in case of immediate loading for a full arch replacement. Several reports show that a syncrystallization - welded framework exhibits a more precise fit than a one-piece casting. The intra-olral syncrystallization welding technology can not only create a passive-fitting implant prosthesis, but also pre-fabricate implant components, including titanium bars and attachments, and can be syncrysallization-assembled directly on the master cast. This article describes a technique developed to fabricate an immediately loaded prosthesis using syncrysallization a new component for welding a passive-fitting implant prosthesis.The aim of this article was to describe a technique developed for an accelerated rigid splinting of multiple implants for same-day immediate loading with metal-reinforced provisional restorations using a technique of welding temporary implant abutments with a prefabricated titanium connection tab directly performed in the oral cavity. Between June 2009 and July 2011, immediate loading of threaded implants with a metal- reinforced acrylic resin provisional restoration at stage 1 surgery was evaluated in 22 consecutive patients. A total of 232 implants were placed in selected edentulous patients using the syncrystallization technique. All of the 232 rigidly temporized immediately loaded implants were osseointegrated. An implant success rate of 100% was achieved over a period of 6 months postplacement. No fracture or luting cement failure of the provisional restoration occurred during the observation time. The technique allows for a highly accurate, passively fitting prosthesis in only 6 hours with excellent patient satisfaction

A COSMETIC TECHNIQUE CALLED LIP REPOSITIONING IN PATIENT OF EXCESSIVE GINGIVAL DISPLAY

Excessive gingival display can be managed by a variety of treatment modalities, depending on the specific diagnosis. A 29-year old woman was referred to the Unit of Oral Surgery of the University of Chieti-Pescara by her dentist for a consultation regarding a gummy smile. A partial-thickness dissection was made. The epithelium and connective tissue was excised. Tissue tags were removed. The mucosal flap was advanced and sutured at the mucogingival junction using 5-0 polypropylene sutures and 4.0 chromic gut sutures. No periodontal dressing was placed. Postoperative instructions included recommendations for limited facial movements, no brushing around the surgical site for 14 days, and placing ice packs over the upper lip. This treatment modality was effective, producing esthetically acceptable smiles in these patients. This case report demonstrates the successful management of excessive gingival display with a lip-repositioning procedur

SURFACE ANALYSIS OF FAILED ORAL TITANIUM IMPLANTS AFTER IRRADIATED WITH ErCR:YSGG 2780 LASER

Peri-implantitis may occur because of biologic or mechanical factors. They can be treated by a variety of methods. Aim of the present study was to evaluate implant surface of failed oral titanium implants after irradiated with ErCR:YSGG 2780 laser. This study comprised 45 implants removed for peri-implantitis reasons. The implants were divided into two groups: group I (Control): 22 non-irradiated implants, group II (Test): 23 irradiated implants. Immediately after extraction, the second group’s implants were irradiated with an ErCR:YSGG 2780 laser (Waterlase MD Turbo-Biolase). Control and test implants were processed with SEM analysis. At higher magnification in the coronal portion no bacteria were found on test implant surface. At low magnification, there was a variation in the number of fields of deposit among the non-irradiated implants and different portions on the same implants. At higher magnification, deposits were identified as connective tissue in apical portion and bacteria or others, in coronal portion of control implants. In conclusion, ErCR:YSGG 2780 laser is recommended to be used in implant surface detoxification without any surface alteration, using the experimental conditions

CLINICAL, RADIOGRAPHIC, AND HISTOPATHOLOGICAL EVALUATE OF AMELOBLASTOMAS TREATED CONSERVATIVELY AND CURETTAGE WITH ULTRASONIC SURGERY

Treatment of ameloblastomas is controversial. On one hand there is a school advocating major segmental or bloc resection for ameloblastoma with a reqruitment of 1-1.5 cm of clinically and radiographically normal bone and uninvolved margins. 9 On the other hand, there is a school advocating more conservative surgical management by enuclation with adjacent bone curettage The aim of this study was to evaluate the clinical, radiographic, and histopathological findings and of one case of ameloblastomas over 50 years treated conservatively with enucleation and curettage with ultasonic surgery. A 50-year old woman was referred to the Department of Oral Surgery of the University of Chieti-Pescara complaining of swelling at the left posterior mandible. CT examination shwovs intense destruction of bone trabeculae was observed from the midline ascending to the mandibular body, mandibular ramus and angle at the right side. We made a gingival crevicular incision with vertical releasing incisions to create a trapezoid-shaped flap. After mobilization of the full-thickness vestibular mucoperiostal flap, vestibular ostectomy was done with a ultrasonic surgery device (NSK Variosurgery Dentalica, Milano, Italy), the lesion was exposed and it was enucleated through this access. After enucleation of the lesion a curettage is performed by ultrasonic surgery the walls of the bone cavity. The histopathological diagnosis is follicular ameloblastoma. After 12 and 24 months after surgery the radiography exhibited a new bone formation was evident. Subsequent check-ups have been performed for 12 and 24 months to date, there have been no signs of recurrence. Each case is unique and has to be considered in the clinical context and the relationship of the lesion to surrounding tissues, histological type and recurrences rate. In conclusion ultrasonic surgery device facility the remove of lesion and bone healing

SKIN LESIONS INDUCED FROM THE RADIOSURGICAL UNIT AND VOLTAIC ARC DERMOABRASION: A RABBIT MODEL

The aim of this study was a histological evaluation of skin lesions induced from the radiosurgical unit and voltaic arc dermoabrasion: a rabbit model. Materials and methods: eight New Zealand male rabbits with a weight average 3.9 Kg, participated in this study. Dorsal part of each rabbit was shaven and divided in two equal parts of 5 cm. Voltaic arc dermoabrasion ( Plexer, GMV s.r.l. Grottaferrata, Italy) in one side and radiosurgical unit (Laser elettronica Milano 1,75 MH) on the other were used to remove the keratinized layer. In each area were performed 10 sites of abrasion for a total of 20 sites per rabbit. The animals were sacrificed in groups of two at days: 0, 7, 14 and 21 with a Tanax overdose. The treated skin was removed using a scalpel and a block section containing the subcutaneous layer was effectuated. There were obtained 20 biopsies from each block section, 10 performed with el- bras and 10 with radiosurgical unit for a total of 40 biopsies per study time. Results: the present results demonstrated the possibility on containing the thermal damage of the lesions adjacent tissues using dermoabrasion. There were no observations of thermal damage on the underlying dermal tissue. Absent necrotic layer on the healing process was shown but an inflammatory infiltrate was present. The reduced thermal damage on the subcutaneous tissue is probably due to the current passage absence on the tissues. This is necessary to close the electric circuit between the active electrode and the neutral one in which the patient is part when using the radiosurgical unit. The arc voltaic dermoabrasion technique in comparison with the electroscalpel demonstrated the capability to contain the damage within the parenchym

A Human Clinical, Histological, Histomorphometrical, and Radiographical Study on Biphasic HA-Beta-TCP 30/70 in Maxillary Sinus Augmentation

Background: By mixing hydroxyapatite (HA) and tricalcium phosphate (TCP), biphasic calcium phosphate ceramics can be obtained, and by varying their ratio it is possible to tailor the characteristics of the biomaterial. Purpose: The aim of the present human study was to evaluate the histological and radiographical aspects of bone formation in maxillary sinus augmentation using a 30/70 HA-beta-TCP with a reticular structure. Materials and Methods: A total of 12 patients, undergoing two-stage sinus augmentation procedure using HA-beta-TCP at a ratio of 30/70, were included in the present study. After a 6-month healing period, during implant insertion, radiographical analysis was performed, and then the bone core biopsies were harvested and processed for histology. Results: At radiographic evaluation, the bone gain was on average 6.85±0.60mm. HA-beta-TCP 30/70 appeared to be lined by newly formed bone, with no gaps at the interface. The histomorphometric analysis revealed 26±2% of residual grafted biomaterial, 29±3% of newly formed bone, and 45±2% of marrow spaces. Conclusions: The present results indicate histologically the high biocompatibility and osteoconductivity of HA-beta-TCP 30/70, and clinically its successful use for sinus augmentation procedures