Stefano Benedicenti

Long-term survival of endodontically treated, maxillary anterior teeth restored with either tapered or parallel-sided glass-fiber posts and full-ceramic crown coverage

OBJECTIVES This retrospective study investigated the clinical effectiveness over up to 8 years of parallel-sided and of tapered glass-fiber posts, in combination with either hybrid composite or dual-cure composite resin core material, in endodontically treated, maxillary anterior teeth covered with full-ceramic crowns. METHODS The study population comprised 192 patients and 526 endodontically treated teeth, with various degrees of hard-tissue loss, restored by the post-and-core technique. Four groups were defined based on post shape and core build-up materials, and within each group post-and-core restorations were assigned randomly with respect to root morphology. Inclusion criteria were symptom-free endodontic therapy, root-canal treatment with a minimum apical seal of 4mm, application of rubber dam, need for post-and-core complex because of coronal tooth loss, and tooth with at least one residual coronal wall. Survival rate of the post-and-core restorations was determined using Kaplan-Meier statistical analysis. RESULTS The restorations were examined clinically and radiologically; mean observation period was 5.3 years. The overall survival rate of glass-fiber post-and-core restorations was 98.5%. The survival rate for parallel-sided posts was 98.6% and for tapered posts was 96.8%. Survival rates for core build-up materials were 100% for dual-cure composite and 96.8% for hybrid light-cure composite. CONCLUSIONS For both glass-fiber post designs and for both core build-up materials, clinical performance was satisfactory. Survival was higher for teeth retaining four and three coronal walls.

Intracellular ATP level increases in lymphocytes irradiated with infrared laser light of wavelength 904 nm.

OBJECTIVE Red and near-infrared laser irradiation is reported to have a range of biological effects on cultured cells and different tissues, leading to the hypothesis that laser light can affect energy metabolism. Increased adenosine triphosphate (ATP) synthesis has been reported in cultured cells and rat brain tissue after irradiation at 632.8 nm and 830 nm, respectively. This study investigated whether diode pulsed laser irradiation enhances ATP production in lymphocytes. MATERIALS AND METHODS Aliquots (500 microL) of an extract of cultured lymphocytes of the Molt-4 cell line were irradiated with diode laser light (lambda = 904 nm, pulsed mode, 6 kHz frequency) with an average emission power of 10 mW for 60 min. A Spectra Physics M404 power meter was used to measure light intensity. Controls were treated similarly but not irradiated. The amount of ATP was measured by the luciferin-luciferase bioluminescent assay. RESULTS The amount of ATP in irradiated cell cultures was 10.79 +/- 0.15 microg/L (SD; n = 10), and in non-irradiated cell cultures it was 8.81 +/- 0.13 microg/L (SD; n = 10). The average percentage increase of irradiated versus control cell cultures was about 22.4% +/- 0.56% SD (p < 0.001). CONCLUSION This significant increase is probably due to laser irradiation; it cannot be attributed to any thermal effect, as the temperature during irradiation was maintained at 37.0 degrees +/- 0.5 degrees C. Thus the therapeutic effects of the biostimulating power of this type of laser are identified and its indications may be expanded.

Miniscrew design and bone characteristics: an experimental study of primary stability.

INTRODUCTION The purpose of this study was to evaluate the correlations between bone characteristics, orthodontic miniscrew designs, and primary stability. METHODS Four different miniscrews were placed in pig ribs. The miniscrews were first scanned with a scanning electron microscope to obtain measurable images of their threads. Subsequently, the maximum insertion torque of the screws and the maximum load value in the pullout force tests were measured; furthermore, bone specimen characteristics were analyzed by using cone-beam computed tomography. For each bone sample, the insertion site cortical thickness as well as both cortical and marrow bone density were evaluated. The nonparametric Kendall rank correlation (tau) was used to evaluate the strength of the associations among the characteristics measured. The nonparametric Kruskall-Wallis test was used to evaluate the differences among the groups, and post-hoc comparisons were assessed by using the Nemenyi-Damico-Wolfe-Dunn test. RESULTS A significant dependence was found between pitch and maximum insertion torque (tau, -0.49). Positive correlations were also found between pullout force and maximum insertion torque (tau, 0.64), cortical thickness (tau, 0.36), and marrow bone density (tau, 0.35). CONCLUSIONS In this in-vitro experimental study, strong correlations were observed among miniscrew geometry, bone characteristics, and primary stability.

Head and Neck Hemangiomas in Pediatric Patients Treated with Endolesional 980-nm Diode Laser

PURPOSE In pediatric patients with hemangiomas, vascular malformations, or lymphovenous malformations, therapeutic decisions frequently pose a challenge to surgeons, dermatologists, radiologists, and pathologists. We analyze the value of an interdisciplinary approach, and treatment of hemangiomas with an endolesional 980-nm diode laser. PATIENTS AND METHODS Between 2000 and 2008 we provided interdisciplinary consultation for patients with hemangiomas, lymphangiomas, and vascular anomalies. We treated 250 patients with a 980-nm diode laser. In patients with hemangiomas and venous malformations, clinical diagnosis was confirmed by color Doppler flow imaging and magnetic resonance imaging; angiography was employed for patients with arteriovenous malformations. All patients were either treated by laser surgery or treated conservatively depending on lesion size and behavior. RESULTS Two hundred fifty pediatric patients were treated; these included 160 patients with hemangiomas, 50 with vascular malformations, and 40 with lymphatic malformation. The treatment results were analyzed by evaluating the decrease in lesion size and the lesions complete clinical disappearance. All patients had resolution except 38 for whom there was a reduction in lesion size that required a new session. CONCLUSIONS The interdisciplinary approach increases diagnostic accuracy, and subsequently improves individual treatment for pediatric patients with hemangioma, lymphangioma, and vascular anomalies. The diode laser was found to be useful in the treatment of lesions in pediatric patients in terms of aesthetic results and resolution.

Mandibular condylar hyperplasia: clinical, histopathological, and treatment considerations.

Abstract Condylar hyperplasia is a rare disorder characterized by an increased volume of the condyle, ramus, and mandibular body leading to facial asymmetry. We present three cases of condylar hyperplasia: two women and one man, age range 27 to 34. Clinically, all three patients showed a deviation of the mandible to the opposite side and a protruded position of the chin, hypertrophy of the lower border of the mandible, combined with an elongation of the mandibular ramus, open-bite on the deformed side, and cross-bite on the opposite side. In all three cases, scintigraphy showed an increased uptake. Radiography and CT scanning confirmed the clinical diagnosis and patients were subjected to surgery, comprising high condylectomy on the affected side with access in the pre-tragus area. The surgical piece sent to the Institute of Pathological Anatomy for histological examination revealed a nonuniform picture, in terms of both the depth of cartilage islands and the thickness of the fibrous layer covering the joint surface. Common to all three cases, however, was the apparent evolution of fibrous tissue to cartilage, and of this to compact bone tissue. At two-four years, all cases have maintained a good occlusal response. The asymmetric deformity of the mandible resulting from the rare condition of hemimandibular hyperplasia is presented and the clinical, histopathological and therapeutic aspects discussed.

Treatment of hemangioma of the head and neck with diode laser and forced dehydration with induced photocoagulation.

OBJECTIVE The aim of this study was to investigate the efficacy of treating oral hemangiomas using forced dehydration with induced photocoagulation (FDIP) via diode laser. METHODS One-hundred sixty patients were treated between 1999 and 2006 (76 men, 46%; 84 women, 54%). In 136 cases we used FDIP to treat hemangioma, and in 24 cases complete surgical excision was performed. One-hundred thirty-four lesions had a surface area <2 x 2 cm2, whereas only two had large lesions measuring 2.5 x 2 cm2. RESULTS In 136 patients with hemangiomas treated with FDIP, 134 cases (98.53%) showed complete remission, one case (0.735%) did not show complete remission, and one case (0.735%) displayed tumor growth. There were no adverse effects and all patients were carefully followed-up until complete healing was documented, along with any complications. CONCLUSIONS Our findings suggest that FDIP is a useful and effective treatment for benign oral vascular lesions. FDIP treatment of these oral lesions is clinically significant because it provides effective management, avoids recurrence, and shortens healing time. We believe that the use of this method by medical and dental specialists should be supported.

Block Allograft Technique versus Standard Guided Bone Regeneration: A Randomized Clinical Trial

PURPOSE The aim of this randomized clinical trial was to compare the potential of deproteinized bovine bone added to autologous bone or corticocancellous allograft block with or without the addition of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) to regenerate mandibular atrophic ridges. MATERIALS AND METHODS TRIAL DESIGN parallel, allocation ratio of 1:1 using a split-mouth model. Eligibility criteria for patients: adult patients; bilateral atrophic edentulous areas in the posterior area of the mandible; a preoperatory cone beam computed tomography scan; and absence of systemic diseases affecting the bone metabolism. Bone graft intervention for control group consisted of bone chips collected with a scraper mixed with deproteinized bovine bone covered with a resorbable membrane. Bone graft intervention for test group consisted of a corticocancellous allograft block, shaped before surgery, and protected with a collagen membrane. In addition, both groups received rhPDGF-BB or a saline solution as control. As primary outcome quantity, bone variation after a 1-year healing period was considered. A p-value of.05 was considered statistically significant. RESULTS Sixteen patients were enrolled in this trial. A total of 50 implants and 32 bone grafts were placed. All patients concluded the study (no dropouts). Change at 1 year in bone volume was not significantly different between the two groups (p-value = .25). Effect of treatment in terms of change in bone volume at 1 year was not significant (p-value = .89) when saline solution was used while was at limit of significance when rhPDGF-BB was used (p-value = .052). After 1 year, all the implants were successfully integrated. CONCLUSIONS The block allograft and the standard regenerative procedure showed similar results in terms of regenerated bone volume after 1 year of functional loading. The rhPDGF-BB positively influenced soft-tissue healing.

Thread shape factor: evaluation of three different orthodontic miniscrews stability

The thread shape factor (TSF) to evaluate the relationships between geometrical characteristics and mechanical properties of the temporary anchorage devices (TADs) has recently been introduced. This in vitro experimental study evaluated in 30 different tests with three TADs: ORTHOImplant (1.8 mm diameter and 10 mm length; 3M Unitek), Tomas (1.6 mm diameter and 10 mm length; Dentaurum), and Orthoeasy (1.7 mm diameter and 10 mm length; Forestadent). Scanning electron microscopy images were acquired for each TAD to measure the TSF; afterwards, the maximum insertion torque (MIT) was evaluated and thereafter pull-out tests on two differently designed organic bone analogs were carried out using a testing machine with a crosshead speed of 2 mm/minute being applied. One-way analysis of variance with group as factor was performed. Post hoc multiple comparisons Bonferroni test was used. Rank-transformed data were used when asymmetry of data was shown. To assess correlation between characteristics, load, and MIT, Spearmans rank correlation coefficient was used. A P-value of 0.05 was considered statistically significant. Significant direct correlations were found between TSF and depth and both load and MIT. Particularly, a correlation of 0.90 (P < 0.001) was found between depth and MIT for 2.2 mm cortical thickness. The authors conclude that MIT and maximum load values of pull-out test are statistically related to depth of the thread of the screw and to TSF.

Decontamination of Root Canals with the Gallium-Aluminum-Arsenide Laser: An in Vitro Study

OBJECTIVES In this in vitro study, we investigated the bactericidal effects on root canals of 810-nm diode laser irradiation, alone or combined with sodium hypochlorite and citric acid irrigation. MATERIALS AND METHODS One hundred sixteen single-rooted human teeth extracted for periodontal reasons were randomly divided into four experimental groups. The canal of each tooth was prepared with a conventional step-back technique and a pure culture of vancomycin-resistant Enterococcus faecalis grown in brain heart infusion broth was used to contaminate the root canal. The specimens were incubated at 37 degrees C for 15 d in a test tube filled with agar, adding fresh bacterial suspension every 48 h, and sent them for microbiological analysis and bacterial count. Subsequently they were divided into four groups: in group A, 29 teeth were irrigated with 2 mL of 10% citric acid solution; in group B, 29 teeth were irrigated with 2 mL 5.25% sodium hypochlorite (NaOCl) solution; in group C, 29 teeth were irradiated with 810-nm laser energy via a 200-microm optic fiber at 2.5 W power in pulsed mode (10 msec on and 10 msec off) for 5 sec; and in group D, 29 teeth were irrigated with NaOCl, irradiated with the laser, then irrigated with citric acid, and irradiated with the laser, followed again by NaOCl irrigation and laser irradiation. All the samples were again sent for microbiological analysis and bacterial count. RESULTS Group A had a bactericidal effect of 0.041 log mean CFU, that of group B was 3.381 log mean CFU, and that of group C was 1.459 log mean CFU, whereas group D showed the best results, with a bactericidal effect of 7.178 log mean CFU. CONCLUSIONS The use of NaOCl, citric acid, and diode laser energy together have a synergistic effect, increasing treatment efficacy and leading to significantly better decontamination of the root canal.

Clinical and Aesthetic Outcome with Post-Extractive Implants with or without Soft Tissue Augmentation: A 2-Year Randomized Clinical Trial.

BACKGROUND The aesthetic outcome of an implant-supported restoration is first of all dependent on the soft tissue volume. Because the labial bone plate resorbs in every direction after tooth extraction, even when an implant is placed immediately, most patients end up with compromised aesthetics. MATERIALS AND METHODS In this parallel-designed, randomized clinical trial, participants were randomly assigned to the test group (immediate load post-extractive implant treated with subepithelial connective tissue graft placed using the tunnel technique in the labial area) and control group (immediate load post-extractive implant treated without raising a flap) with an allocation ratio of 1:1. Both groups received deproteinized bovine bone mineral. Patients were observed at baseline, crown insertion, 1-year follow-up, and 2-year follow-up. Clinical, radiological and aesthetic parameters were recorded to assess primary treatment outcomes. A random permuted block system was blindly generated ensuring uniformity of the patient allocation during the trial by randomly distributing three participants to the test and three participants to the control group every six treated patients. RESULTS At the 2-year examination, all 47 implants were successfully integrated, demonstrating stability and healthy peri-implant soft tissues as documented by standard clinical parameters. The results showed a soft tissue remodeling of -10% in thickness and -18% in highness in the non-grafted group, whereas in the grafted group there was a gain of 35% in thickness and a slight reduction of -11% in highness. Test group reported an increase of aesthetic result (mean pink aesthetic score [PES] 8) compared with control group (mean PES 6.65). CONCLUSIONS This prospective study demonstrates the effectiveness of placing a soft tissue graft at the time of immediate implant placement in the aesthetic zone. At the 2-year follow-up, test group revealed a better aesthetic outcomes and stable facial soft tissues compared with control group.