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Purpose: Zygomatic implants are considered one of the last options for the rehabilitation of severe maxillary atrophy when standard implants cannot be placed. They offer several advantages but can also present complications. This study aimed to investigate the long-term clinical and radiographic outcomes of zygomatic implant placement., Materials and Methods: A retrospective chart review was conducted, and the inclusion criteria consisted of patients previously treated with zygomatic implants who had Class V or VI maxillary bone atrophy according to Cawood and Howell, and with a minimum follow-up period of 2 years after prosthetic loading. Outcome measures included implant and prosthesis survival rate, biological and biomechanical complications, and Lund-Mackay staging score before and after implant placement., Results: The study included 78 patients who received a total of 274 zygomatic implants. The mean follow-up period was 90.4 ± 26.0 months. Seventeen implant failures occurred, resulting in a survival rate of 93.8%, with a statistically significant negative correlation with smoking habits (P = 0.049), anchorage to the two zygomatic bone cortices (bicorticality) (P 0.001) and soft tissue complications (P 0.001). The prosthetic success rate was 92.3%. A statistically significant increase in maxillary sinus radiopacity was recorded when comparing the situation before and after surgery (P 0.001), and the intrasinus pathway had a statistically significant influence on that increase (P = 0.003)., Conclusions: Zygomatic implants utilised for rehabilitating patients with severe maxillary atrophy have shown favourable outcomes. Nonetheless, owing to potential complications, strict case selection is necessary, combined with regular recall visits and proper oral hygiene maintenance. Furthermore, this type of surgery necessitates specialised training and expertise on the part of the practitioner.

Purpose: To evaluate the effectiveness and accuracy of a proposed duplication technique in terms of one- and three-dimensional discrepancies between an original abutment and polyurethane duplicates obtained through a conventional workflow in single-implant rehabilitation., Materials and Methods: A titanium, shoulderless abutment was chosen for a single-implant cemented rehabilitation. The master cast was made using a plastic-based die system, and the implant portion was separated. The implant section was consecutively duplicated eight times using a manual technique with polyvinyl siloxane and unfilled polyurethane resin as impression and die materials. The duplicates were analyzed with a coordinate-measuring machine (SmartScope Flash 200, Optical Gaging Products): one- and three- dimensional discrepancies were determined for each duplicate on 20 analysis points (A to T) located on the abutment surface. Changes in the abutment radius were also calculated to estimate the effects on cement thicknesses., Results: One-dimensional discrepancies were -0.5 Å} 61.2 μm, -6.6 Å} 39.7 μm, and -19.4 Å} 47.8 μm on the X, Y, and Z axes, respectively; three-dimensional variation was -66.4 Å} 60.1 μm. Friedman test showed no significant difference between duplicates' one-dimensional variations on X (P = .059), Y (P = .156), or Z (P = .223) axes; a significant difference was found regarding three-dimensional changes (P < .001). Dunn test showed higher discrepancies on the X axis and on the abutment head. Mean variation of the abutment radius was -12.09 μm., Conclusions: The abutment duplication technique was shown to be an accurate and repeatable procedure for single cementable restorations.

Objectives: Does the angulation of ultrashort implants influence the stability of the peri-implant bone? The present study aimed to evaluate the effectiveness of non-axial ultrashort implants after 2 to 9 years of follow-up in resorbed alveolar ridges., Materials and Methods: All partially edentulous patients with ultrashort implants (< 6 mm) used in the posterior region of an atrophic mandible or maxilla, to support partial dentures in conjunction with standard implants, were included in this study. Peri-implant bone loss, success and survival rates, crestal bone levels, crown-to-implant ratio and implant angulation were measured for each implant. Implants were divided into two groups: straight implants with angulation < 17° (control group) and tilted implants with angulation > 17° (test group). Statistical analysis was used to find any significant differences between the two study groups and to investigate significant linear correlations among all the variables (p = 0.05)., Results: A total of 42 ultrashort implants with a mean of 4 years of follow-up were included: 20 ultrashort axially loaded implants and 22 tilted implants. Mean crestal bone levels from baseline loading to maximum follow-up did not reveal statistical differences in regard to PBL; mean success and survival rates were 100% in all groups., Conclusions: PBL, success and survival rates of axial ultrashort implants and tilted ultrashort implants are comparable to those of conventional implants., Clinical Relevance: This retrospective study revealed that ultrashort implants, even when placed with an angulation > 17°, can safely be used to support partial fixed prostheses. Further prospective clinical studies with larger samples and prospective design are needed to confirm these findings., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: Up-to-date literature regarding long-term success of implant rehabilitations after microvascular reconstructions with free fibula flap (FFF) is still very scarce. This study aimed to evaluate clinical outcomes, especially related to oral hygiene conditions, of patients rehabilitated with this technique., Materials and Methods: A total of 25 patients who underwent maxillofacial reconstructive surgery with FFF were retrospectively evaluated for soft tissues conditions, oral hygiene habits, and implant survival and success, assessed with a mean follow-up of 6 (range 2-15) years after loading., Results: Fourteen patients received full-arch fixed prostheses and 11 removable bar-supported overdentures. At the follow-up evaluation, 52% of prostheses did not allow proper accessibility for oral hygiene. Overall prosthetic survival was 100%, and implant survival and success were respectively 93.6% and 72%. Prevalence of peri-implantitis was 29% at implant level and that at patient level 96%., Conclusions: Six-year clinical outcomes of this study reveal that poor oral hygiene practices and compliance by patients who underwent maxillofacial reconstruction with FFF are significantly associated with peri-implant disease., Clinical Relevance: Findings of the present study underline the need by clinicians for a careful assessment, in reference to a specific implant therapy, of patient's prosthetic accessibility for oral hygiene procedures., (© 2023. The Author(s).)

Background: Short and ultra-short implants implants supporting single crowns seem to demonstrate high percentages of survival and stable marginal bone levels at a mid-term follow-up. Nevertheless, insurgence of peri-implant complications still represents a critical issue, especially for patients with history of periodontitis., Purpose: The aim of this retrospective study was to evaluate implant survival, marginal bone loss and peri-implant complications in 333 short and ultra-short implants, placed in periodontally healthy patients and patients with a history of periodontitis., Materials and Methods: Implants were placed in the maxillary and mandibular posterior regions of 142 patients with (PP) and without (NPP) a history of periodontitis. Clinical and radiographic examinations were performed at 5-year recall appointments., Results: Implants respectively placed in PP and NPP were: 35.68% and 42.50% in 8.0 mm-length group, 33.33% and 36.67% in 6.0 mm-length group, and 30.99% and 20.83% in 5.0 mm-length group. Implant-based survival after 5 years of follow-up was 95.77% for PP and 96.67% for NPP (p = 0.77). Regarding crestal bone level variations, average crestal bone loss was statistically different (p = 0.04) among PP (0.74 mm) and NPP (0.61 mm). Implants presenting signs of mucositis were 6.86% in PP and 7.76% in NPP (p = 0.76). Setting the threshold for excessive bone loss at 1 mm after 60 months, peri-implantitis prevalence was 7.84% in PP and 2.59% in NPP (p = 0.08). Overall implant success was 92.16% and 97.41%, respectively, for PP and NPP., Conclusions: Under strict maintenance program, five-year outcomes suggest that short and ultra-short locking-taper implants can be successfully restored with single crowns in the posterior jaws both in PP and NPP., (© 2022 The Authors. Clinical Implant Dentistry and Related Research published by Wiley Periodicals LLC.)

Background: Short and ultra-short implants represent a predictable treatment, in terms of implant survival, with patients presenting insufficient available bone volumes. Moreover, single crown restorations represent a gold standard in terms of oral hygiene., Purpose: The aim of this retrospective study was to evaluate implant survival, marginal bone loss, and peri-implant complications in 333 locking-taper short and ultra-short implants., Materials and Methods: Implants were placed in the maxillary and mandibular posterior regions of 142 patients. Clinical and radiographic examinations were performed at 5-year recall appointments., Results: All implants placed consisted of 8.0-, 6.0-, and 5.0-mm length, 38.14%, 34.53%, and 27.33%, respectively. Three hundred thirty-two implants (one early failure) were rehabilitated with single crowns in 141 patients. In 45.48% of the implants the crown-to-implant ratio was ≥2, with a mean value of 1.94. Overall implant-based survival after 5 years of follow-up was 96.10%: 96.85%, 95.65%, and 95.60% for 8.0-, 6.0-, and 5.0-mm length implants, respectively (p = 0.82). Overall patient-based survival was 91.55%. Regarding crestal bone level variations, average crestal bone loss and apical shift of the "first bone-to-implant contact point" position were 0.69 and 0.01 mm, respectively. Setting the threshold for excessive bone loss at 1 mm, during the time interval from loading to follow-up, 28 implants experienced loss of supporting bone greater than 1 mm: 19 of them (67.85%) were surgically treated with a codified surgical regenerative protocol. After 60 months, a peri-implantitis prevalence of 5.94% was reported, with an overall implant success of 94.06%: 95.93%, 92.73%, and 93.10% for 8.0-, 6.0-, and 5.0-mm length implants, respectively (p = 0.55)., Conclusion: Long-term outcomes suggest that short and ultra-short locking-taper implants can be successfully restored with single crowns in the posterior area of the maxilla and mandible., (© 2021 The Authors. Clinical Implant Dentistry and Related Research Published by Wiley Periodicals LLC.)

The introduction of computer-assisted and guided surgery has radically improved the possibility of using all available bone for implant support, reducing the need for extensive grafting procedures and allowing for better implant placement and restoration. Moreover, fresh frozen homologous bone (FFB) grafts have shown good osteoconductive properties and biocompatibility with results comparable to autologous bone patients. The purpose of this retrospective cohort study was to evaluate the survival and the success rate of implants and related fixed full arch prosthesis at the 5 to 8 years follow-up when performed with immediate function using a flapless surgical procedure and computer-aided technology (NobelGuide®, Nobel Biocare® AB, Goteborg, Sweden) in patients previously treated with FFB grafts; treated at the University of Verona with the NobelGuide® system from January 2007 to December 2012 with at least 5 years follow-up were reviewed. Survival implants and survival prosthesis' percentage reached 95% in a 5 to 8-year period. This study indicates that patients previously augmented with FFB graft for maxillary or mandibular bone atrophy can be safely treated with implant supported prosthesis based on the NobelGuide® protocol, with the aid of computer-generated guide., (Copyright 2020 Biolife Sas. www.biolifesas.org.)

The rehabilitation of maxillary bone atrophy represents one of the main challenges of modern oral implantology. The use of zygomatic implants in the prosthetic rehabilitation of the patient affected by severe maxillary bone atrophy is another therapeutic alternative, not exempt from complications. The present study included 19 patients with edentulous maxillae who were treated between 2013 to 2015 with at least two zygomatic implants at the Department of Maxillofacial Surgery, Verona, Italy. The purpose of this retrospective longitudinal study was to evaluate sinus complications and radiological, periodontal and prosthetic evaluations of zygomatic implants technique in severe atrophic. Implant-prosthetic rehabilitation of the upper jaw edentulous severely atrophic using zygomatic implants represents one safe and repeatable technique. In terms of implant survival from our study showed an implant CRS (common reporting standard) of 98.5% and a prosthetic CRS 100% with a mean follow-up period of 19.2 months (range). Both recorded data are superimposed on major reported studies in literature., (Copyright 2020 Biolife Sas. www.biolifesas.org.)

The purpose of this retrospective study was to determine survival and peri-implant marginal bone loss of short and ultra-short implants placed in the posterior mandible. A total of 98 patients received 201 locking-taper implants between January 2014 and January 2015. Implants were placed with a 2-stage approach and restored with single crowns. Clinical and radiographic examinations were performed at 3-year recall appointments. At that time, the proportion of implant survival by length, and variations of crestal bone levels (mean crestal bone loss and mean apical shift of the "first bone-to-implant contact point" position) were assessed. Significance level was set at 0.05. The total number of implants examined 36 months after loading included: 71 implants, 8.0 mm in length; 82 implants, 6.0 mm in length; and 48 implants, 5.0 mm in length. Five implants failed. The overall proportion of survival was 97.51%, with 98.59% for the 8.0-mm implants, 97.56% for the 6.0-mm implants, and 95.83% for the 5.0-mm implants. No statistically significant differences were found among the groups regarding implant survival (P = .73), mean crestal bone loss (P = .31), or mean apical shift of the "first bone-to-implant contact point" position (P = .36). Single-crown short and ultra-short implants may offer predictable outcomes in the atrophic posterior mandibular regions, though further investigations with longer follow-up evaluations are necessary to validate our results.

Purpose: To evaluate the role of middle meatal antrostomy in preventing the onset of maxillary sinusitis after placement of zygomatic implants. We hypothesized that middle meatal antrostomy might reduce the incidence of this complication., Materials and Methods: A prospective longitudinal study was performed of patients who had undergone placement of 4 zygomatic implants and concurrent middle meatal antrostomy with an endoscopic approach at the maxillofacial surgery unit of Verona University. The radiological results of the maxillary sinuses were evaluated on computed tomography scans performed 12 months after surgery using the Lund-Mackay staging system. Clinical symptoms were evaluated both preoperatively and 12 months after surgery using the Sino-Nasal Outcome Test-20 (SNOT-20). Intraoperative violation of the Schneiderian membrane was also assessed. The outcomes from the present study were compared with historical controls., Results: The sample included 13 patients, 26 maxillary sinuses with negative radiologic findings of sinonasal pathologic features, and 52 zygomatic implants. A moderate increase was found in radiologic findings of sinonasal pathologic features postoperatively compared with preoperatively, with mucosal hypertrophy in 3 maxillary sinuses (11.5%). The incidence and severity of mucosal hypertrophy was significantly lower than the outcomes of the historical controls. The average preoperative SNOT-20 score was 13.45, and the postoperative SNOT-20 score was 1.18. The Schneiderian membrane was pierced in 13 sinuses in 9 patients., Conclusions: Shrinkage of the ostiomeatal complex seems to play a fundamental role in the onset of sinonasal pathologic features after zygomatic implant placement compared with implant-related causes. Although functional endoscopic sinus surgery is a supplementary surgical method in implant placement, it seems to provide statistically significant improvement in the health of the sinonasal system. Perforation of the Schneiderian membrane does not appear to correlate with the onset of sinus opacification and sinonasal symptoms., (Copyright © 2019. Published by Elsevier Inc.)

Background: The aim of this study was to evaluate radiological and histological characteristics of fresh-frozen homologous bone as grafting material for maxillary sinus floor augmentation. Radiological, histological and clinical evaluations were made., Methods: Twenty-three patients with a 2 mm to 6 mm alveolar ridge height in the posterior maxilla have been enrolled. Unilateral or bilateral sinus floor augmentations were performed with fresh frozen morcelized homologous bone. Together with implant placement, 7 months after surgery, a bone core was harvested for histological analysis. Radiological measurements were obtained by superimposition of CT scans carried out at the surgery time and six months later. A total of 93 implants were positioned., Results: A mean (±SD) increase in mineralized tissue height of 10.74±2.82 mm was noticed by comparing the CT scans. Histological analysis revealed the presence of newly formed bone in the grafted sites. The follow up period after the prosthetic load ranged from 8 to 31 months. One implant failure occurred., Conclusions: Fresh frozen homologous bone seems to have a good healing pattern and to be a successful and steady grafting material for the treatment of maxillary ridge atrophy. It might be considered a valid alternative to autologous bone in sinus floor augmentation procedures.

The atrophic posterior ridges are usually characterized by poor bone quality and quantity: this situation requires the use of bone regenerative techniques. Other alternative surgical approaches are investigated. Nowadays the use of tilted implants offers some advantages due to its feasibility. Today, bone grafting may be practical, but depends on many factors, such as the type of bone graft used (autogenous, alloplastic, or xenograft), host response, age of the patient, various complications associated with grafting procedures, infection, and, most importantly, the time spent while the grafted material matures and is taken up by the bone. So this case report describes the feasibility of an alternative surgical technique.

The first option in the rehabilitation of the posterior atrophic maxilla is the sinus lift. The aim of this study is to highlight the characteristics that a sinus lift should have to maximize the subsequent implant survival rate. 33 systematic reviews regarding sinus lift procedures, implants success and survival rates were identified through scientific archives and analysed. The obtained results indicated that a heterogeneity of sinus lift procedures are described in the literature. The sinus lift should be performed through the apposition of particulate xenograft materials, in at least 4mm residual bone. Implants should have a rough surface and the patient should be non-smoker.

Objectives: To assess the clinical, microbiologic, and radiologic status of soft and hard tissues surrounding zygomatic implants., Study Design: Patients who had at least two zygomatic implants were eligible for the study. Their soft tissues were analyzed, and microbial samples were collected. Cone beam computed tomography (CBCT) and orthopantomography were used to measure bone levels. The patients were also asked to complete a Visual Analogue Scale (VAS) questionnaire assessing their satisfaction., Results: A total of 65 zygomatic implants placed in 20 patients were assessed. As one zygomatic implant was lost, the cumulative survival rate was 98.5%. All the prostheses were successful. Peri-implant soft tissues were generally in a healthy condition. The patients with a history of periodontitis had worse mean peri-implant clinical parameters and showed more bacterial colonization with respect to their nonperiodontal counterparts. The implant recipients had low levels of crestal and zygomatic bone loss and high VAS scores indicating their general satisfaction., Conclusions: Although zygomatic implants were confirmed to be a reliable treatment option, patients with a history of periodontitis were, nevertheless, found to have special needs, such as frequent dental hygiene sessions., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: Concerns have been expressed about the possibility of high insertion torque (IT) causing necrosis, impaired osseointegration, and crestal bone loss over time. The present study investigated the relationship between primary stability and implant success, including early and late maintenance of crestal bone levels., Materials and Methods: Implants were placed in patients at three study centers. Every effort was made to achieve the highest possible primary stability, which was measured with IT and implant stability quotient (ISQ). The IT and ISQ at insertion and reopening (3 to 4 months), as well as bone levels at several points in time, were recorded. The correlations between IT, ISQ, and immediate and 3-year crestal bone loss were investigated through linear regression analyses., Results: Average IT was 76.1 ± 20.8 Ncm, while the average ISQ score was 80.4 ± 8.4. The implant success rate at 36 months was 98.6%. The crestal bone loss around most implants (41.0%) ranged from 0.05 to 0.5 mm. None of the osseointegrated implants had crestal bone loss greater than 2.5 mm. The linear regression analysis showed no correlation among early or 3-year crestal bone loss and IT, ISQ at surgery, and ISQ at reopening., Conclusion: The implants studied avoided any negative effects deriving from the high IT values (≥ 50 Ncm) applied during 3 years of follow-up.

Purpose: The purpose of the present study was to analyze the relation between zygomatic implants and symptomatic and radiologic modifications of the maxillary sinuses., Materials and Methods: A retrospective cohort study of patients who underwent zygomatic implant rehabilitation at the Clinic of Dentistry and Maxillofacial Surgery of the University of Verona from January 2005 through May 2014 was designed. The primary predictor variable was time (pre- vs postoperative). Concerning outcome variables, radiologic findings of thickened mucosa or opacification of the maxillary sinuses were evaluated on computed tomograms using the Lund-Mackay Staging System. Clinical symptoms were evaluated using the Sino-Nasal Outcome Test-20 (SNOT-20). The parameters assessed underwent descriptive statistical analysis., Results: The sample was composed of 41 patients (mean age, 54 yr; 61% women). Preoperatively, 12% had sinus findings. Postoperatively, 46% had sinus findings (P = .0001 by McNemar paired test). Preoperatively, 12% had a SNOT-20 score higher than 11. Postoperatively, 15% had a SNOT-20 score higher than 11 (P = 1 by McNemar paired test)., Conclusions: In accordance with data in the literature data, placement of zygomatic implants does not seem to be associated with severe rhinosinusitis complications. However, in a considerable number of patients, asymptomatic radiologic alterations of the paranasal sinuses were observed. Therefore, it is important to plan assessments of the prosthetic and peri-implant components of the procedure and the postoperative homeostasis of the maxillary sinuses., (Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: The study shows how the influence of titanium surfaces on human mesenchymal stem cells differentiates toward osteocytes lineage and how, after growth, on machined titanium disk or etched titanium disk, changes, in gene expression for RUNX1, CTNNB1, SP7, and DLX5., Methods: Genes were analyzed by means of quantitative real-time polimerase chain reaction. Osseo genic lineage differentiation was also tested by means of the catenin-β1 immunofluorescence, induced osteoblasts, which represented the internal control., Results: The RUNX1 and SP7 expressions in the induced osteoblasts prove to be different, compared with cells cultured on metallic supports. Moreover, the levels of expression of the runt-related transcription factor 1 and the osterix appeared more down-regulated in cells that grew on a machined titanium surface. In the present experimental model, mRNA expression of DLX5 and CTNNB1 in human mesenchymal stem cells, cultured on each of the titanium surfaces, showed no differences, compared with osteoblast-induced cells. The immunofluorescence scores, for protein expression of beta-catenin in human mesenchymal stem cell treated cells, illustrates significantly improved results with the etched surface., Conclusions: Present results suggested that different titanium surfaces might induce some differences in terms of gene expression. The only gene analyzed, which proved significant differences between the 2 titanium supports, was SP7; however, the other 3 genes indicating the existence of differences between the 2 titanium groups.

Aim: Objective of this study was to assess the influence of the subcrestal placement level of short implants with a locking-taper connection design on crestal bone levels and soft tissues health., Methods: A clinical retrospective case-control study was conducted between May 2013 and September 2013. The sample was composed of patients who had received at least one 5-to-8-mm-long, plateau-design implant with a locking-taper connection system (Bicon LLC, Boston, MA, USA) in posterior areas of maxilla and mandible, in the period between January 2009 and Dicember 2011. A radiographic evaluation of the degree of subcrestal positioning(t0) was conducted to identify two implant groups: Group 1 was composed of implants placed less than 2 mm under the crestal bone; Group 2 was composed of implants placed 2 mm or more under the crest. The primary outcome variables were the crestal bone levels and the peri-implant bone loss between prosthetic loading and last control visit (t1àt2). Clinical parameters including the keratinized gingival (KG) width, modified bleeding index (mBI), modified plaque index (mPI), and probing depth (PD) were assessed at the follow-up visit. T tests were conducted to identify statistically significant differences between implants groups. Linear regression models were developed to test the dependence of the study variables by the degree of subcrestal surgical implant placement. Significance level was set at P<0.05., Results: One hundred and thirty-seven implants were followed for an average period of 31 months. At the surgery, the implants were placed, on average, 2.04 mm (mesial) and 1.86 mm (distal) subcrestally. Eighty implants were placed less than 2 mm under the crest (average 1.28 mm), while fifty-seven implants were placed more than 2 mm under the crestal bone (average 2.97 mm). At the prosthetic loading (t1), the average crestal bone level was 1.11 mm, 0.79 mm in Shallow group and 1.86 mm in Deep group, with statistically significant differences between implant groups (P<0.05). At the follow-up visit (t2) the mean crestal bone levels were respectively 0.51 mm and 1.35 mm, with statistically significant differences between implant groups (P<0.05). The average peri-implant bone loss between prosthetic loading and control visit (t1àt2) was 0.04 mm in the Group 1 and 0.33 mm in Group 2. The average keratinized mucosa width was 2.16 mm, the average mBI was 0.24 , the average mPI was 0.17 and the average PD was 2.34 mm. Significant difference between groups was observed regarding to keratinized gingival width (Group 1: 1.97 mm; Group 2: 2.41 mm; P<0.05) but not for the other clinical parameters. Linear regression models confirmed the dependence of crestal bone levels by the degree of subcrestal placement (P<0.05)., Conclusion: After two years of observation, the implant of this study have shown minimal peri-implant bone resorption. The greater subcrestal implant placement has resulted in a higher level of the peri-implant bone crest, both after the osseointegration period and after the loading period. Both the study implants groups have shown good health of peri-implant soft tissues.

Patients affected by severe maxillary atrophy and skeletal malocclusion have been widely treated by simultaneous orthognathic surgical procedures, interpositional bone insertion and immediate or delayed implant placement. Although several authors have described that the "quad" technique using 4 zygomatic fixtures as an effective way to fully rehabilitate the severe atrophic maxilla, there are still no experiences relative to the use of zygomatic fixtures associated to maxillary osteotomies in case of large skeletal discrepancy. The aim of this study is to report a 1-step surgical rehabilitation of severe atrophic maxilla by means of Le Fort I osteotomy for maxillary forward repositioning and simultaneous insertion of 4 zygomatic implants with immediate prosthetic loading.

Objectives: The aim of this prospective study was to determine how the crown-implant ratio (C/I ratio) influences crestal bone loss and implant success rates after a 3-year follow-up, using implants with a sintered porous surface (SPS)., Materials and Methods: On the basis of preestablished inclusion and exclusion criteria, 151 of a cohort of 160 patients with single or partial edentulism were selected as eligible for the study. The 151 patients were treated consecutively from 2005 to 2007 using 280 SPS implants, which were restored with a single crown or a partial fixed denture. The data collection included both clinical and anatomical C/I ratios; other implant prosthetic factors were also recorded. Implants were divided into three groups according to the C/I ratio. Clinical and radiographic examinations were scheduled over a 36-month follow-up of functional loading according to a well-established protocol generally applied to determine implant success rates and crestal bone levels. Statistical analysis was used to determine any significant differences or correlations (P = 0.05)., Results: A total of 259 SPS implants in 136 patients were followed up for 36 months. According to the success criteria, the overall implant-based success rate was 98.1%, and the mean peri-implant bone loss (PBL) was 0.48 ± 0.29 mm. Statistical analysis revealed significant correlation between implant success rate and C/I ratio (P < 0.05) and between PBL and C/I ratio (P < 0.05). The critical threshold value of the anatomical and clinical C/I ratio for avoiding excessive bone loss or implant failure was 3.10 and 3.40., Conclusion: This prospective cohort study revealed that SPS implants offer a predictable solution for implant prosthetic rehabilitation in patients with edentulism characterized by different alveolar bone atrophy. From the biomechanical point of view, the C/I ratio would appear to be the main parameter capable of influencing implant success and crestal bone loss. Consequently, it is important not to exceed the threshold values in order to avoid excessive stress at the bone-implant interface capable of resulting in excessive crestal bone loss or implant failure., (© 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.)

The behavior of fresh-frozen homologous bone (FFB) when used in combination with computer-guided implant surgery has not been investigated yet, and there is a lack of clinical evidence in the literature. The purpose of this retrospective study is to evaluate the implant survival and related fixed full-arch prostheses at the 1- to 5-year follow-up when performed with immediate function using a flapless surgical procedure and computer-aided technology (NobelGuide; Nobel Biocare AB, Goteborg, Sweden) in patients previously treated with FFB grafts. Furthermore, the related values of torque and complications observed were analyzed and discussed. Clinical charts of patients with edentulous arches treated with FFB grafts and NobelGuide system with at least 1 year follow-up were reviewed retrospectively.A total of 65 patients met the criteria of inclusion, receiving a total of 342 implants and 77 full-arch prostheses, with a mean follow-up of 32.87 months (range, 1-5 years). Survival of implants and prostheses was high, reaching 96.5% and 95%, respectively. Factors significantly related to failure of the implants were smoking, position of the implant as last distal abutment, and fracture of basal maxillary bone. Prostheses survival was influenced by bruxism, failure of multiple implants, and torque level of implant equal to 0 at implant insertion. All implants and prostheses failures occurred in the first year. A higher torque level at implant insertion did not correspond to a lower risk of implant failure.Within the limitations of our retrospective study, this treatment modality was predictable with high survival rates and high insertion torque. However, a few implant and prosthetic failures were found, together with several complications.

This clinical report describes the successful implant-supported prosthetic rehabilitation of a patient who underwent subtotal bilateral maxillectomy for an oral squamous cell carcinoma with a consequent wide defect interesting the whole hard palate and most of the soft palate, causing a large opening that directly connects the oral cavity to the nasal fossa bilaterally. The innovative aspect of this case is represented by the realization of an obturator prosthesis supported by just 3 zygoma implants.The maxillary bone had been largely excised by radical surgery. Despite the resection had a complete oncological success and the patient was free of disease after 24 months' follow-up, the patient experienced severe speech and deglutition deficit due to the iatrogenic large oro-antral communication. Three zygoma implants have been positioned, 2 through the right maxillary bone and, owing the wide lack of bone, just 1 on the left side. No mucogingival surgery was necessary around the zygoma implants. The obturator prosthesis was stabilized by the 3 implants and the patient's oral function as well as quality of life widely improved.The results show that zygoma implants could represent a viable surgical option to obtain a satisfactory oral function rehabilitation even in case of extensive maxillary defect.

Implant-supported prostheses are a predictable treatment of totally edentulous patients. Progresses in implantology allowed realizing prostheses that are supported by immediately loading implants. Implants can be inserted in the healed site as fresh extraction sites, without differences about long-term results. Using computer-assisted surgery, it is possible to insert implants in a predetermined position and to create a prostheses, which can be immediately fixed on the implants. Patients have major comfort and an immediate aesthetic and functional result. The use of computer-assisted surgery in fresh extraction sites is a procedure that has not been evaluated because of technical difficulties: teeth extraction eliminates references for surgical guides. The absence of guidelines to treat dentulous areas is often likely caused by lack of computer-assisted surgery: we attempted to use this procedure to replace residual teeth with an immediate implant prosthetic rehabilitation. The aim of this clinical report was to show the possibility to apply computer-assisted surgery in dentulous patient using a double surgical template: one before extraction and the other after extraction of selected teeth.

This report documents a case of bisphosphonate-related osteonecrosis of the jaw (BRONJ) after dental implant placement in an osteoporotic patient treated with alendronate for 6 years. A 63-year-old patient underwent rehabilitation of the posterior mandible with 2 dental implants in 2006 while taking alendronate to treat osteoporosis. The surgical procedure was uneventful. Both implants integrated well, and in November 2006 the patient wore a fixed partial prosthesis. Alendronate was never discontinued. In June 2008 a painful cheek swelling of the left mandible developed, associated with gingival bleeding. Since then, the patient underwent several courses of antibiotics, without relief of symptoms. In June 2009 the patient was referred to our department. An area of infected and exposed necrotic bone in the left mandible enclosed 1 dental implant. A panoramic radiograph and computed tomography scan showed an increased bone marrow density with peri-implant bone sequestration. The technetium Tc 99m scintigraphy-labeled granulocytes were positive for active bone infection. Bone exposure persisted for 8 weeks, and diagnosis of oral nitrogen-containing bisphosphonate (N-BP)-related osteonecrosis was made. On the basis of a review of the literature, this is the 10th case of BRONJ after implant placement in patients taking oral N-BPs. Despite the low risk of BRONJ occurrence after implant surgery in oral N-BP users, the fate of dental implants in these patients remains uncertain. Therefore patients at risk must be given a full explanation of the potential risks of implant failure and BRONJ development. Because the potential role of infection is still debated, great attention should be paid to the long-term oral hygiene of implant-prosthetic restorations., (Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Recently, many authors have investigated the results of immediately loaded implants in fresh extraction sites, reporting favorable success rates, but only a few studies have included a long-term follow-up in the maxilla with analysis of clinical and radiographic data. The aim of this study was to evaluate the predictability of the immediate loading protocol with fast bone regeneration (FBR)-coated implants placed in postextractive sites in the maxilla, considering the success rate after at least 5 years of follow-up. Moreover, the clinical and radiographic results are evaluated in terms of soft tissue conditions and crestal bone loss values. One hundred fifty-eight implants were inserted following dental extraction in 70 consecutively operated patients. Each implant was immediately prosthesized. The data were collected before surgical planning, at the time of insertion, and after 3 and 5 years of occlusal loading. Specific success criteria were used to assess the success rate of immediately loaded postextraction implants. Clinical and radiographic examinations were used to determine long-term results. After a 5-year follow-up, 2 implants were lost, with a cumulative success rate of 98.7%. The radiographic and clinical data revealed well-maintained hard and soft tissues, with acceptable long-term results. The use of immediately loaded FBR-coated implants in fresh extraction sockets is shown to be a predictable technique if implants are inserted in selected cases and positioned with great care, following thorough preoperative analysis.