Diffusion of light through quartz fiber-reinforced epoxy resin double taper posts.

PURPOSE: The aim of this study was to evaluate the progression of the light through a series of translucent posts available on the market (D.T. Light-post, R.T.D.). MATERIALS & METHODS: nine D.T. Light-posts (DTLPs) were analyzed, 3 for each available measure. Each post was trans-illuminated both in vertical trans-ilumination (VTI) and oblique trans-illumination (OTI), via a light curing unit (LCU) (V.I.P., Bisco), in complete darkness conditions, and the resulting image of the post, was digitally acquired with a 1:1 ratio. The images were then analyzed using digital image analysis software (Image Pro plus 4.1, Media Cybernetics) previously performing the light intensity calibration, of the LCU, by means a radiometer (Curing Radiometer model 100, Demetron Corp.). The evaluation of the progression of the light through the posts was conducted for each post along its longitudinal axis. RESULTS: no significant differences concerning VTI vs OTI for DTLP n.1 (p = 0.341) and DTLP n. 3 (p = 0.115), while for DTLP n.2 a significant difference was observed (p = 0.041); Conclusion: The results demonstrate that the greater the section of the post, the greater its ability to transmit light at a distance; also the vertical Trans-illumination of the post is to be preferred to the oblique one.

Upper full arch rehabilitation with sinus by-pass with tilted implants via tapered-threaded expanders in low density bone: a clinical trial.

PURPOSE: In the present paper the use of tapered-screw bone expanders (TSBEs) is proposed, in combination with the placement of tilted implants, in close proximity to the anterior sinus wall, solving the problem of the reduced height of the alveolar bone in the sub-antral area. The Authors present a case series of full-arch rehabilitations performed with this procedure named: Tilted Implant Expansion Osteotomy (TIEO). MATERIALS AND METHODS: 12 patients (5 males and 7 females, average age 58.5 ± 8.1 years) with totally or partially edentulous maxilla were enrolled in this study. For each patient 4 implants were placed, the anterior implants in the area of lateral incisors or canines while, the posterior implants, immediately in front of the maxillary sinus, with an inclined position. Adopting the aforesaid procedure, 48 cylindrical two-piece implants were placed, 24 of which were placed in tilted position, in order to by-pass the maxillary sinus. After a healing period of 6 months, the second stage surgery was performed. The cases were finalized by means of a hybrid metal-acrylic prosthesis. The post finalization follow-up was at 12 months. RESULTS: Survival rate was 100% since none fixtures were lost. At the one-year follow up the clinical and radiological appearance of the soft and hard tissues was optimal and no pathological signs were recorded. CONCLUSION: TIEO is a promising surgical procedure for full-arch rehabilitation of maxillary edentulous sites and represents a therapeutic alternative to sinus lift techniques.

The use of various biomaterials in computer-guided crestal sinus lift procedures. A report on two case studies with volume comparison.

PURPOSE: In the context of the transcrestal maxillary sinus lift a wide variety of biomaterials have been used to fill the subantral space over the years. In this study, two types of biomaterials were used in order to fill the maxillary sinus: a nano-crystallized hydroxyapatite in an aqueous solution and a micronized heterologous bone in a collagen matrix. MATERIALS AND METHODS: The surgical procedures were designed and carried out using computer-guided surgery. The filling volume obtained was measured with a comparative software program. RESULTS: A ≥ 6 millimeter augmentation of osseous volume was obtained. This result is comparable to those obtained in lifts where conventional techniques were applied. The technique used was very precise and the difference between the projected and clinical outcome of the implant position had an average of less than 0.3 millimeters. CONCLUSIONS: This technique allows for the surgery to be performed in a way which is both minimally traumatic and invasive, and represents a viable alternative to those surgical techniques for crestal sinus lift currently in use.

Efficacy of a new implant-abutment connection to minimize microbial contamination: an in vitro study.

PURPOSE: The aim of the present study is to evaluate the effectiveness of Ditron implants abutment connection (IAC) to sealing the gap between two pieces. MATERIALS AND METHODS: To identify the efficacy of a new IAC, the passage of genetically modified bacteria across IAC was evaluated. A total of five Ditron Implants were used. All implants were immerged in a bacterial culture for forty-eight hours and then bacteria amount was measured inside and outside IAC with Real-time PCR. Bacterial quantification was performed by Real-Time Polymerase Chain Reaction using the absolute quantification with the standard curve method. RESULTS: In all the tested implants, bacteria were found in the inner side, with a median percentage of 1.35%. The analysis revealed that, in untreated implants, bacteria grew (internally and externally). Moreover, the difference between outer and inner bacteria concentration was statistically significant at each time point. CONCLUSIONS: Ditron Implant IAC (MPI, Ditron Dental, Israel) is efficacy in reducing bacterial leakage.

Endoscopic retrieval of a dental Implant into the maxillary sinus: a case report.

PURPOSE: In this article the Authors show a safe and predictable technique to remove displaced implants from the maxillary sinus. MATERIALS AND METHODS: A 49-year-old female was referred, to this centre by a general dentist, for the retrieval of the ectopic dental implant. After a preliminary clinical and radiological evaluation of the case the surgical procedure was performed. A loco-regional anesthesia was carried out and then the Maxillary Sinus Retrieval Device (MSRD), proposed in this study, was inserted in the canine fossa, via a circular antrostomy 5,5mm wide, previous execution of a mucoperiosteal flap. The MSRD is a trocar, modified with a funnel-shaped cannula in order to allow the easy access of both an endoscope and a suction cannula or, in alternative, a straight forceps. The implant was easily found end retrieved thanks to the endoscopic control. The postoperative was uneventful and no nasal bleeding was reported by the patient. CONCLUSION: The Authors recommend the use of the MSRD in order to minimize the biological sacrifice consequent to the implant retrieval in the maxillary sinus.

Full arch rehabilitation in severe maxillary atrophy with palatal approach implant placement: a case report.

PURPOSE: The edentulous severely atrophic maxilla, as consequence of alveolar bone resorption and pneumatisation of the maxillary sinus, represents a serious limitation to the implant rehabilitation. Implants insertion via palatal approach (PA), in combination with relatively minimally invasive techniques aimed at increasing bone volume without the use of autologous bone harvesting is a valid alternative among the options for the rehabilitation of the upper jaw. CLINICAL CASE: In a 70-year-old female, with a severe maxillary atrophy, 6 spiral taper implants were placed with the PA, combined with the bilateral transcrestal elevation of both the sinus floors and nasal cavities; a further GBR, with resorbable pericardium membrane covering a termoplastic allograft associated to a xenograft, was performed. The second stage was performed after 6 months. Implant prosthetic functionalization was carried out in 4 months by placing the removable prosthesis in direct contact with the healing cup screws. After that period the case was finalized with a hybrid prosthesis. Clinical and radiographic follow-ups were carried out at 6 months and at one year after prosthetic finalization, during which no pathological signs were recorded. CONCLUSIONS: The PA implant insertion described by the Authors, combined with bone augmentation procedures, performed in the same stage, may represent a valid and reliable solution to rehabilitate maxillary edentulous patients.

Endoscopic management of the schneiderian membrane perforation during transcrestal sinus augmentation: a case report.

PURPOSE: In this article the Authors describe a procedure aimed to restore under endoscopic control, the continuity, of the Schneiderian membrane (SM) incidentally teared during a sinus lift with transcrestal approach. MATERIALS E METHODS: In a 44-year-old male, due to aforementioned complication, the SM was gently detached via transcrestal approach, with a customized small ball burnisher, in order to facilitate the placement of a collagen sponge, to close the communication with the sinus, followed by the subsequent insertion of a graft material. All the procedure was endoscopically controlled and, considering the successful grafted area elevation, was simultaneously followed by implant placement. After 6 months the second stage was performed always under endoscopic control. RESULTS: The endoscopic view of the grafted area showed a dome-shaped elevation sited on the top of the implant, the SM was apparently normal with no signs of inflammation, the antrum was empty and normally functioning. Periapical X-rays were performed: immediately after the surgery; at both 14 days and 6 months post-operative; at 6 months post prosthetic finalization. The volume of the grafted area progressively decreased over the time while its radiopacity, on the contrary, gradually increased, as expected after graft integration and remodelling. The implant was submitted to no functional load for 4 months by means of a temporary screwable acrylic crown inserted on a peek abutment and then finalized with a cementable metal-ceramic crown on a preformed titanium abutment. CONCLUSION: The Authors recommend the use of endoscope to repair the SM incidentally teared during transcrestal sinus lift.

Guided bone regeneration via a preformed titanium foil: clinical, histological and histomorphometric outcome of a case series.

PURPOSE: The aim of this paper was to evaluate the histological and histomorphometric outcome of Preformed Titanium Foil (PTF) to perform Guided Bone Regeneration (GBR) in posterior mandibular atrophies. MATERIALS AND METHODS: 10 subjects (1 male; 9 females; mean age 58±11.37 years), with distal mandibular atrophies were selected to perform GBR by means of PTF, using a moldable allograft paste as graft material. The devices, made of a 0,2 mm thick pure titanium foil, were pre-shaped using stereolithographic models obtained from CT-scan of the patients' recipient site. In the second stage, performed at 6.7±2.33 months, 18 cylindrical two-piece implants were placed and the devices removed, at the same time bone biopsies were harvested. At 4 months, the implants were exposed and submitted to progressive prosthetic load for a span of 4 months. The cases were finalized by means of metal-ceramic cementable restorations. The post finalization follow-up was at 12 months. RESULTS: Survival rate (i.e. SVR) was 100% since none fixtures were lost. At the one-year follow up the clinical appearance of the soft tissues was optimal and not pathological signs on probing were recorded. The success rate (i.e. SCR) was 88.2% and the average peri-implant bone reabsorption was 1.17±0.41 mm. The average rate of graft contraction was 19.4±10.55%. The mean percentage occupied by mineralized bone was 48.03±5.93%, while the bone marrow and graft material were 36.1±2.81% and 15.87±4.87 %, respectively. CONCLUSION: The results suggest good potentialities of the method for GBR in distal mandibular atrophies, allowing to maximize the outcome and simplifying the surgical phase.