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Marco Lelli,1 Olivia Marchisio,2 Ismaela Foltran,1 Annamaria Genovesi,2 Giulia Montebugnoli,1 Massimo Marcaccio,1 Ugo Covani,2 Norberto Roveri11Alma Mater Studiorum, University of Bologna, Department of Chemistry, Bologna, Italy; 2University of Pisa, Istituto Stomatologico Tirreno, Lido di Camaiore, Lucca, ItalyAbstract: Titanium plates treated in vitro with a mouthwash containing amine fluoride (100 ppm F-) and another containing zinc-substituted carbonate–hydroxyapatite have been analyzed by scanning electron microscopy and atomic force microscopy to evaluate the modification of the surface roughness induced by treatment with these two different mouthwashes. The treatment with F--based mouthwash produces a roughness characterized by higher peaks and deeper valleys in the streaks on the titanium bracket surface compared with those observed in the reference polished titanium plates. This effect causes a mechanical weakness in the metallic dental implant causing bacterial growth and therefore promotes infection and prosthesis contamination. However, the in vitro treatment with a mouthwash containing zinc-substituted carbonate–hydroxyapatite reduced the surface roughness by filling the streaks with an apatitic phase. This treatment counteracts the surface oxidative process that can affect the mechanical behavior of the titanium dental implant, which inhibits the bacterial growth contaminating prostheses.Keywords: mouthwash, titanium brackets, corrosion, hydroxyapatite, aminic fluoride

Purpose: Orthopedic surgeons use different types of screws for bone fixation. Whereas hard cortical bone requires a screw with a fine pitch, in softer cancellous bone a wider pitch might help prevent micromotion and eventually lead to greater implant stability. The aim of this study was to validate the assumption that fine-pitch implants are appropriate for cortical bone and wide-pitch implants are appropriate for cancellous bone. Materials and Methods: Wide-pitch and fine-pitch implants were inserted in both hard (D1 and D2) bone and soft (D3 and D4) bone, which was simulated by separate experimental blocks of cellular rigid polyurethane foam. A series of insertion sites in D1-D2 and D3-D4 experimental blocks were prepared using 1.5-mm and 2.5-mm drills. The final torque required to insert each implant was recorded. Results: Wide-pitch implants displayed greater insertion torque (20% more than the fine-pitch implants) in cancellous bone and were therefore more suitable than fine-pitch implants. Conclusion: It is more appropriate to use a fine pitch design for implants, in conjunction with a 2.5-mm osteotomy site, in dense cortical bone (D1 or D2), whereas it is recommended to choose a wide-pitch design for implants, in conjunction with a 1.5-mm osteotomy site, in softer bone (D3 or D4). Int J Oral Maxillofac Implants 2010;25:883-887. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the clinical success and bone healing of implants placed in fresh extraction sockets using a flapless procedure compared to those placed with flap elevation. Materials and Methods: Twenty teeth in 20 patients were selected for this study and were scheduled for tooth extraction and immediate implant placement. Ten implants were placed with flap elevation (control group), and 10 implants were placed without flap elevation (test group). All the sites selected showed a complete bone defect at the facial wall. All the implants included in this study were 2-stage implants placed at the level of palatal/lingual bone in augmented bone. Each surgical site was protected with a collagen membrane and, subsequently, a standardized radiograph was taken to evaluate the distance between the implant shoulder and the first bone-implant contact (DIB). Six months after placement, both control and test implants underwent a second-stage surgery and a clinical examination to determine the implant stability quotient, DIB, and the distance between implant shoulder and the crestal bone at the midbuccal aspect (DIC). Results: One implant failed in the test group. Only 1 implant (test group) showed bone growth over the implant neck at the re-entry procedure. Implant stability quotient (ISQ) and DIB did not show any significant differences between the control and test group; however, a higher DIC was found in the test sites compared to the control sites. Conclusion: Data from this study showed that immediate implants with and without a mucoperiosteal flap elevation can be successfully used even in the presence of bone defects requiring augmentation procedures. It was also noted that the bone regenerated reached a higher coronal level in the group with flap elevation than in the group without flap elevation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the clinical success of implants placed in fresh extraction sockets with simultaneous maxillary sinus floor elevation using the osteotome technique. Twelve patients were included. All the patients required the extraction of a maxillary premolar--close to the maxillary sinus--and were scheduled for immediate implant placement. One experimental implant was placed per patient, with an 18-month follow-up period. The graft materials used in both sinus augmentation and peri-implant bone defects were a mixture of collagen gel and corticocancellous porcine bone particles. All implants were allowed to heal for 6 months prior to prosthetic rehabilitation. One of the 12 experimental implants failed because of an abscess during early healing. No implants failed after definitive prosthetic rehabilitation. No significant bone loss was detected at the final follow-up visit. The mean bone height before sinus elevation and implant placement was 7.8 mm. Eighteen months after surgery, the mean bone height was 12 mm. When adequately performed, the surgical procedure described in the present study--immediate implant placement and simultaneous sinus floor elevation--appears to be unproblematic and predictable in terms of clinical success. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aims of this prospective clinical study were (1) to evaluate the clinical performance of Signum composite inlays over a 3-year period; (2) to investigate the clinical efficacy of composite inlays in premolars versus molars; and (3) to evaluate differences between 1- or 2-surface inlays and multisurface inlays. METHOD AND MATERIALS: One hundred thirteen composite inlays were placed in 30 patients by a clinician. All the inlays were made by the same laboratory technician using only one composite material (Signum, Heraeus Kulzer). All the restorations were bonded with a 3-step bonding system and a composite luting cement. The restorations were assessed after placement by a clinician who had not been involved with the placement of the restorations, in accordance with the modified US Public Health Service criteria. RESULTS: Three of the 113 experimental restorations had to be replaced; the total failure rate was 2.6% after 3 years. At baseline, 88.5% to 100% of the inlay restorations were rated as excellent (Alpha). Statistically significant (P < .05) differences were observed during the study for surface roughness, anatomic form at the margin, marginal integrity, and inlay integrity. The comparison of the clinical outcome of inlays in premolars versus molars and with 1 or 2 surfaces versus multisurfaces showed no significant differences, except for the parameters anatomic form at the margin and marginal integrity. CONCLUSION: Composite inlays demonstrated a very high success rate (97.4%) after 3 years. Neither the size of the restorations nor the tooth type significantly affected the clinical outcome of the restorations. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this study was to retrospectively evaluate the clinical performance of bonded indirect resin composite onlays for the treatment of painful, cracked teeth over a 6-year period. MATERIALS AND METHODS: Forty-three posterior teeth diagnosed as having a crack were selected in the restorative department of the University of Genoa. Inclusion criteria were sensitivity to biting and cold and a clinically visible crack. Direct composite buildup after removal of the existing restoration was performed before definitive cavity preparation. All composite onlay restorations were cemented with an adhesive technique using a 3-step total etch system and a dual-cure composite cement. Patients were interviewed and clinically examined at 1 week, 4 weeks, and every 6 months. RESULTS: The effectiveness of bonded onlay restorations was evaluated for a mean observation time of 4.78 years. At 1 week, 38 (88.37%) restored teeth were free of pain, 3 (6.98%) still had sensitivity to cold, and 2 (4.65%) still had sensitivity to cold and chewing. At 4 weeks, 40 (93.02%) teeth were free of pain, 2 (4.65%) still had sensitivity to cold and chewing, and 1 (2.32%) needed endodontic treatment. Two other teeth (4.65%) also needed endodontic treatment, the first after 2 months and the second after 5 months. During the evaluation period, 3 restorations (6.98%) failed, and upon clinical examination, 40 (93.02%) teeth were free of symptoms with a 6-year survival rate of 93.02% (life table analysis). CONCLUSIONS: Bonded indirect resin composite onlays can be successful in treating painful, cracked teeth. From the findings of this study, it appears that cuspal protection should be incorporated into the design of coronal restorations. [ABSTRACT FROM AUTHOR]

PURPOSE: The aim of the present clinical trial was to evaluate the 12-month success rate of titanium dental implants placed in the posterior mandible and immediately loaded with 3-unit fixed partial dentures. MATERIALS AND METHODS: Patients with missing mandibular premolars and molars were enrolled in this study. To be included in the study, the implants had to show good primary stability. Implant stability was measured with resonance frequency analysis using the Osstell device (Integration Diagnostics). Implants were included in the study when the stability quotient (ISQ) exceeded 62. Clinical measurements, such as width of keratinized tissue, ISQ, and radiographic assessment of peri-implant bone crest levels, were performed at baseline and at the 12-month follow-up. The comparison between the baseline and the 12-month visits was performed with the Student t test for paired data (statistically significant at a level of alpha = 0.05). RESULTS: Forty implants with a sandblasted, large grit, acid-etched (SLA) surface (Straumann) were placed in 20 patients. At 12 months, only 1 implant had been lost because of an acute infection. The remaining 39 implants were successful, resulting in a 1-year success rate of 97.5%. Neither peri-implant bone levels, measured radiographically, nor implant stability changed significantly from baseline to the 12-month follow-up (P > .05). DISCUSSION: The immediate functional loading of implants placed in this case series study resulted in a satisfactory success rate. CONCLUSION: The findings from this clinical study showed that the placement of SLA transmucosal implants in the mandibular area and their immediate loading with 3-unit fixed partial dentures may be a safe and successful procedure. [ABSTRACT FROM AUTHOR]

PURPOSE: Osteoblast attachment on titanium surfaces is necessary to achieve new bone formation and osseointegration. The purpose of this study was to examine osteoblast attachment on irradiated titanium disks. MATERIALS AND METHODS: Machined, hydroxyapatite (HA)-coated, sandblasted, and titanium plasma-sprayed (TPS) surfaces were irradiated with either a carbon dioxide (CO2) or an Er,Cr:YSGG laser. A control group of nonirradiated disks was also examined. Osteoblast cultures were cultivated on the titanium disks and examined with scanning electron microscopy. RESULTS: The findings demonstrated that osteoblasts could be grown on all of the surfaces. Pseudopodia and a spread of cells that demonstrated maturation were observed on the lased irradiated titanium disks. CONCLUSIONS: The data show that laser irradiation of titanium surfaces may promote osteoblast attachment and further bone formation. [ABSTRACT FROM AUTHOR]

PURPOSE: The aim of this study was to evaluate the rate of complications in maxillary sinus augmentation surgery and the impact of complications on subsequent implant treatment in a patient population with severe maxillary atrophy scheduled for treatment under general anesthesia. MATERIALS AND METHODS: The study population consisted of 70 patients (124 sinuses) with severe maxillary atrophy who underwent maxillary sinus augmentation. Sixteen patients were scheduled to have a unilateral procedure and 54 patients a bilateral procedure. Sinus augmentation was performed with autogenous bone alone in 93 sinuses; in 31 sinuses, a 1:1 mixture of autogenous bone and corticocancellous pig bone particles was used. Twenty-six of 124 procedures involved both sinus augmentation and autogenous block grafting for the treatment of severely atrophic maxillae. RESULTS: The most common intraoperative complication was the perforation of the sinus membrane, which was observed in 31 sinuses (25%). Seven (5.6%) sinuses in 7 patients exhibited suppuration of the maxillary sinus. Five of the 7 patients with sinus infection were smokers, showing a prevalence of complications significantly greater in smokers compared to nonsmokers. Moreover, the use of an onlay bone graft in conjunction with sinus augmentation appeared to significantly increase the rate of infective complications. Infections were treated by drainage and the administration of systemic antibiotics. Two clinical cases showing persistent signs of infection required an endoscopic inspection of the maxillary sinus. DISCUSSION AND CONCLUSION: In the present study sinus membrane perforation was not shown to be a significant factor in the rate of implant complications. However, the combination of smoking and onlay bone grafting could significantly increase the rate of postoperative infection following sinus grafting. [ABSTRACT FROM AUTHOR]

The aim of the present clinical study was to evaluate the placement of transmucosal implants into fresh extraction sockets and their immediate restoration with temporary crowns. A series of 22 cases with a 12-month follow-up is presented. Twenty-two patients (15 women and 7 men; mean age 39 years) who needed a single tooth replaced because of vertical or horizontal root fracture, caries, endodontic lesions, or periodontal disease were treated with immediate postextraction implant placement. The implant was then restored with a screw-retained prosthetic restoration within 24 hours. Radiographic assessments were made at baseline and 12 months after implant placement. Clinical parameters, such as plaque score, mucositis score, probing attachment level, mucosal margin position, variation of gingival level, and variation of papilla position, were also measured at baseline and after 12 months of follow-up. At 12 months, no implants had failed. Radiographic examination revealed mean bone resorption of 0.5 mm at 12 months compared to baseline. The mean variation of gingival level, compared to the neighboring teeth, was -0.75 mm. Probing attachment levels were 0.79, 0.45, and 0.54 mm at proximal, buccal, and lingual sites, respectively. The values for the mucosal margin position were 2.9, 2.2, and 2.4 mm at proximal, buccal, and lingual sites, respectively. Regarding variation of papilla position, according to Jemt's index, 27 papillae presented with a score of 2 (61%) and 17 with a score of 3 (39%). An examination of oral hygiene and peri-implant soft tissue conditions at the 12-month follow-up visit revealed an overall frequency of plaque-carrying implant surfaces of 13%. Furthermore, mucositis (score 2) was not observed at any of the peri-implant units. Primary implant stability did not significantly increase over time. The immediate restoration of dental implants placed into fresh extraction sockets was shown to be a safe and predictable procedure. The success rate and radiographic and clinical results were comparable to those obtained following the standard protocol. Within the limits of the present investigation, immediate restoration of single-tooth implants placed in fresh extraction sockets can be considered a valuable option to replace a missing tooth. However, long-term clinical trials are needed to confirm the present results. [ABSTRACT FROM AUTHOR]

PURPOSE: The aim of this prospective clinical study was to evaluate the survival rates at 12 months of transmucosal implants placed in the posterior mandible and immediately restored with single crowns. MATERIALS AND METHODS: Thirty ITI dental implants with sandblasted, acid-etched surfaces were placed in 30 patients missing at least 1 mandibular molar and immediately restored if acceptable primary stability was attained. Primary stability was measured with resonance frequency analysis (RFA) using the Osstell device, and only implants with a stability quotient greater than 62 were included in the study. RFA measurement and radiographic assessment were made at baseline and 6 months after implant placement. Plaque Index, Bleeding Index, probing depth, attachment level, and width of keratinized tissue were measured at the 12 month follow-up examination. RESULTS: At 12 months, only 1 implant had been lost; it was removed because of acute infection. Radiographic as well as clinical examination confirmed osseointegration of all implants, with a survival rate of 96.7%. DISCUSSION: Interestingly, implant stability as measured using RFA did not increase significantly from baseline to 12 months (P > .05). CONCLUSION: The present study showed that immediate restoration of transmucosal implants placed in the mandibular area with good primary stability can be a safe and successful procedure. However, larger, long-term clinical trials are needed to confirm the present results. [ABSTRACT FROM AUTHOR]

PURPOSE: The purposes of the present study were to evaluate implants placed immediately after tooth extraction without incision or primary flap closure and to observe the peri-implant soft tissue healing. MATERIALS AND METHODS: Fifteen patients (9 men and 6 women) aged 31 to 54 years were included in this study. Each patient had a tooth that required extraction, and each had at least 4 mm of bone beyond the root apex. Teeth with multiple roots were excluded from this study. After tooth extraction, the implants were immediately placed without incision or flap elevation. Implant sites showing bone fenestrations, bone dehiscences, or peri-implant bone defects exceeding 2 mm were excluded from this study. In these cases, a standard guided bone regeneration procedure with a surgical flap elevation was used. The second-stage surgical procedure was performed 6 months after the first procedure. The following clinical parameters were evaluated at the time of implant placement and at second-stage surgery: levels of mesial and distal papillae, width of keratinized mucosa, position of mucogingival junction relating to the surrounding tissues, and peri-implant radiolucency and marginal bone loss, which were evaluated radiographically. RESULTS: The postsurgical healing period was uneventful for all patients. Soft tissue closure over the implant sites was achieved in 1 to 3 weeks after surgery at all sites. At second-stage surgery, no peri-implant bone defects were observed or detected by probing around all the experimental implants. The soft tissue anatomy was considered clinically acceptable in all patients. DISCUSSION AND CONCLUSION: Successful osseointegration and complete bone healing were observed for all patients. The soft tissue healing and morphology were satisfactory; additional mucogingival surgery was not required before definitive prosthetic rehabilitation. [ABSTRACT FROM AUTHOR]

The placement of an implant immediately after tooth extraction may have the following advantages: reduction in morbidity, treatment time, and treatment costs; preservation of the residual ridge width and height; optimal esthetic result; and easier definition of implant position. The aim of the present study was the presentation of a human clinical and histologic report involving a nonsubmerged implant placed in a mandibular postextraction site and removed because of persistent pain. At low-power magnification, it was possible to see that newly formed bone with wide osteocyte lacunae was present around the implant. A 1.5-mm sulcular epithelium was visible on one side of the implant, with a 0.5-mm epithelial attachment. The thickness of the supracrestal connective tissue was 3.2 mm. This connective tissue was dense, had few cells, was well vascularized, and showed no evidence of an inflammatory infiltrate. Under polarized light, it was possible to observe that the connective fibers were arranged perpendicular to the implant surface and that these fibers became parallel near the implant. These results show that human immediate postextraction implants can have a high percentage of bone-implant contact. [ABSTRACT FROM AUTHOR]

Objectives: The present randomized double-blind clinical trial aimed to compare the efficacy in reducing dentin hypersensitivity of a dentifrice formulation containing nano-hydroxyapatite with a fluoride dentifrice and a placebo. Methods and materials: One hundred and five subjects were recruited to participate in the study. A computer-generated random table with blocking to one of the three study treatments was used in order to have 35 subjects per group: (1) nano-hydroxyapatite 2% gel toothpaste fluoride free; (2) fluoride gel toothpaste; (3) placebo. Groups 1, 2, and 3 were instructed to treat their teeth for 10 min twice a day with the provided toothpaste gel. The participant's dentin hypersensitivity was evaluated at baseline and after 2 and 4 weeks using airblast and tactile tests. In addition, a subjective evaluation using a visual analogue scale was used. Results: Significant lower values of cold air sensitivity and tactile sensitivity ( p < 0.05) were found for the test group at 2 weeks and 4 weeks. In addition, statistically significant ( p < 0.05) lower values of sensitivity were reported for group 1 compared to those for groups 2 and 3 at 2 and 4 weeks, respectively. The VAS scores were significantly lower ( p < 0.05) in the test group at 2 and 4 weeks compared to those at baseline and in the control groups. Conclusion: The application of nano-hydroxyapatite in gel toothpaste fluoride free is an effective desensitizing agent providing relief from symptoms after 2 and 4 weeks. [ABSTRACT FROM AUTHOR]