Definitive Abutments Placed at Implant Insertion and Never Removed: Is It an Effective Approach? A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

PURPOSE: To assess whether repeated abutment disconnections and reconnections have any impact on peri-implant bone resorption and soft tissue healing. MATERIALS AND METHODS: Electronic and manual searches were conducted for English-language articles published up to March 2017 that identified a relation between repeated disconnections of implant abutments (PA group) and prosthetic or implant failures, complications, marginal bone loss (MBL), soft tissue healing, and esthetic evaluation (pink esthetic score [PES]) after at least 1 year of function compared with implants receiving a final abutment at the time of implant placement (DA group). RESULTS: Fourteen articles (535 patients with 994 implants) were selected for qualitative analysis. Six of these were included in the meta-analysis. Five prostheses failed in the PA group and 1 failed in the DA group (P = .1047). Seven biologic complications occurred in the PA group and 6 occurred in the DA group (P = .8121). MBL was significantly less in the DA group (difference, 0.279 mm; P = .000). Greater buccal recession occurred in the PA group (difference, 0.198 mm; P = .0004). The PES evaluation showed no differences between groups (P = .289). CONCLUSIONS: Repeated abutment disconnections and reconnections considerably increased MBL and buccal recession. Further studies are needed to confirm these results.

Dental implants treatment outcomes in patient under active therapy with alendronate: 3-year follow-up results of a multicenter prospective observational study.

OBJECTIVE: To evaluate the 3-year clinical and radiographic data of fixed implant-supported dental prosthesis delivered to patients having taken alendronate 35-70 mg weekly for at least 3 years before implant placement. MATERIALS AND METHODS: Forty consecutive patients treated with oral bisphosphonates and requiring an implant-supported restoration were recruited in two private centers between January 2008 and December 2011. Implants were inserted through minimally invasive approach under antibacterial and antibiotic treatment, 6 months after alendronate administration stopping. After 4 months of submerged healing, implants underwent prosthetic loading. Hygiene maintenance and clinical assessments were scheduled every 4 months for 3 years. Outcome measures were the following: implant and prosthetic success, survival rates, any observed clinical complications, marginal bone remodeling, probing pocket depth and bleeding-on-probing. RESULTS: At the end of the study, eight patients dropped out. The final sample size resulted in 32 consecutive partially or fully edentulous patients (32 females; mean age 64.6 years) with 98 submerged implants. In only one patient, maxillary implant failed during healing period. No prosthesis failed during the entire follow-up, and no major complications were recorded. Implant and prostheses success resulted in an overall survival rate of 98, 98% and 100%, respectively. Three-year mean marginal bone loss was 1.35 ± 0.21 (CI 95% 1.24-1.38). Successful soft tissue parameters were found around all implants. CONCLUSIONS: Oral bisphosphonate therapy did not appear to significantly affect implant survival and success in case of accurate treatment time selection, minimally invasive surgical approach and constant follow-up. Further prospective studies involving larger sample sizes and longer durations of follow-up are required to confirm these results.

Open reduction and internal fixation of extracapsular mandibular condyle fractures: a long-term clinical and radiological follow-up of 25 patients.

BACKGROUND: During the last 2 decades, many studies on the treatment of mandibular condyle fracture have been published. The incidence of mandibular condyle fractures is variable, ranging from 17.5% to 52% of all mandibular fractures. This retrospective study evaluated the long-term clinical and radiological outcomes after surgical treatment of 25 patients with a total of 26 extracapsular condyle fractures. METHODS: We used 2 types of surgical approaches, the retromandibular retroparotid or preauricular approach. Three kinds of rigid internal fixation plates were used-single plate, double plate, and trapezoidal plate. The following post-operative clinical parameters were evaluated: dental occlusion, facial nerve functionality, skin scarring, and temporomandibular joint functionality. All patients underwent post-operative orthopanoramic radiography and computed tomography. The patients were also monitored for complications such as Frey's syndrome, infection, salivary fistula, plate fracture, and permanent paralysis of the facial nerve; the patient's satisfaction was also recorded. RESULTS: Of the 25 patients, 80% showed occlusion recovery, 88% had no facial nerve injury, and 88% presented good surgical skin scarring. The patients showed early complete recovery of temporomandibular joint functionality and 72% of them were found to be asymptomatic. The postoperative radiographs of all patients indicated good recovery of the anatomical condylar region, and 80% of them had no postoperative complications. The average degree of patient satisfaction was 8.32 out of 10. Our results confirm that the technique of open reduction and internal fixation in association with postoperative functional rehabilitation therapy should be considered for treating patients with extracapsular condylar fractures. CONCLUSION: The topic of condylar injury has generated more discussion and controversy than any other topic in the field of maxillofacial trauma. We confirm that open reduction and internal fixation is the treatment of choice for patients with neck and sub-condylar mandibular fractures.

Minimally Invasive Treatment of Lateral Incisors with Guided One-Piece or Two-Piece Titanium-Made Narrow Diameter Implants: A Retrospective Comparative Study with Up to Two Years Follow-Up.

Restoring teeth with dental implants has become the gold standard in recent years, especially in the esthetic zone. However, limited amount of available bone as well as limited interdental space in the anterior zone may create problems for implant treatment. Narrow diameter implants (NDI) may be a treatment option to resolve the above-mentioned limitations and providing minimally invasive implant therapy without additional regenerative procedures. In this retrospective study, a comparison of clinical and radiographic outcomes between one-piece and two-piece titanium-made NDIs was done with the follow-up of two years after loading. Twenty-three NDI cases were analyzed, 11 in the one-piece implant group (group one) and 12 in the two-piece implant group (group two). The outcomes were implant and prosthetic failures, any complications occurred, peri-implant bone level changes, and as well as the Pink Esthetic score. No implant or prosthetic failures, as well as, no complications were reported at the two-year follow-up examination. At the same time the marginal bone loss was 0.23 ± 0.11 in the group one and 0.18 ± 0.12 in the group two. Difference was not statistically significant (p = 0.3339). The Pink Esthetic Score, recorded two years after definitive loading, was 12.6 ± 0.97 in the group one and 12.2 ± 0.92 in the group two, with no statistically significant difference between groups (p = 0.3554). With the limitations of the present study, including the small sample size and short follow-up, it is possible to conclude that either one and two-piece NDI can be successfully used to restore lateral incisors with comparable results within the two years of follow-up.

Comparison between Early Loaded Single Implants with Internal Conical Connection or Implants with Transmucosal Neck Design: A Non-Randomized Controlled Trial with 1-Year Clinical, Aesthetics, and Radiographic Evaluation.

To evaluate the implant and prosthetic of two implants with different surfaces and neck design. Enrolled patients received bone level, 12° conical connection implants (Nobel Parallel, Nobel Biocare; NOBEL group) with anodized surface (TiUnite) and roughness of 1.35 µm, or transmucosal implant system (Prama, Sweden and Martina; PRAMA group) with convergent collar, ZIrTi surface, and roughness 1.4-1.7 µm. Both implants were made of pure grade IV titanium, with similar diameter and length, chosen according to the dentistry department availability and patient's request. After early prosthesis delivery, patients were filled for at least one year. Outcome measures were: implant and prosthetic survival and success rates, physiological marginal bone remodeling, periodontal parameters and pink esthetic score (PES). Results: Fifteen patients were allocated and treated in each group. At the one-year follow-up, three patients dropped out, one in the NOBEL group and two in the PRAMA group. During the entire time of investigation, all implants survived and the prostheses were successful. No statistically significant differences were found in term of marginal bone loss, periodontal parameters, and aesthetics (p > 0.05). Conclusion: With the limitations of the present study, both implant systems showed successful clinical results. Finally, many other clinical and surgical variables may influenced marginal bone levels, implant survival, and periodontal parameters. More homogenous clinical trials with larger samples are needed to confirm these preliminary conclusions.

Five-Year Prospective Study on Implant Failure and Marginal Bone Remodeling Expected Using Bone Level Implants with Sandblasted/Acid-Etched Surface and Conical Connection.

OBJECTIVE: The purpose of the present prospective, case-series study was to report implant survival rate and marginal bone remodeling expected 5 years after loading using dental implants placed in daily practice. MATERIALS AND METHODS: This research was designed as an open-cohort, prospective, case-series evaluation. Any partially or completely edentulous patient, scheduled to receive at least one bone level implant, was considered eligible for this study. Primary outcome measurements were: implant and prosthetic cumulative survival rate and any complications experienced up to the 5-year follow-up. Secondary outcome measures were: thickness of gingival biotype, implant insertion torque, implant stability quotient, and marginal bone loss (MBL). RESULTS: Ninety consecutive patients (34 males and 56 females, aged between 24 and 81 years old [mean: 53.2 ± 15.4]) with 243 inserted implants were followed for at least 5 years after loading (mean: 65.4 ± 3.1 months; range from 60 to 72). At the 1-year follow-up, no drop-outs were recorded, but 17 patients (18.9%) with 18 restorations (12.6%) delivered on 34 implants (14%) were lost at the 5-year examination. At the 5-year follow-up examination, six implants lost osseointegration (97.5%). In the same period, four prostheses failed (97.2%). Five complications were reported in five different patients (prosthetic success rate was 96.5%, at patient level). Five years after loading, the mean MBL was 0.41 ± 0.30 mm. The difference from the 1-year data was 0.04 ± 0.19 mm. A statistically significant higher MBL was found for smokers, and patients with thin gingival biotype. The mean implant insertion torque was 42.9 ± 4.8 Ncm (range from 15 to 45 Ncm). Two-hundred and three implants (83.5%) were inserted with an insertion torque ≥35 and ≤45 Ncm. CONCLUSIONS: High implant survival and success rate could be expected with stable marginal bone remodeling up to 5 years after loading. Smoking and thin tissue biotype were the most important variabilities associated with higher MBL. Further research studies are needed to confirm these results.

Accuracy of surgical templates with and without metallic sleeves in case of partial arch restorations: A systematic review.

INTRODUCTION: The aim of the present systematic review was to evaluate whether there were any differences in the three-dimensional accuracy and the implant survival rate of implants placed using computer-assisted planning and surgical templates with or without metallic sleeves. SOURCES: This systematic review was written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered to the PROSPERO (International prospective register of systematic reviews) database. STUDY SELECTION: PICOS (population, intervention, control, outcomes, and studies) question was assessed, too. Search strategy encompassed the online (MedLine) literature from 1990 up to December 2020 published in English, and evaluating the accuracy of surgical templates with and without metallic sleeves in partial or complete patients. Only in vivo, randomized controlled trial and observational studies were included. Quality assessment of selected full text articles was performed according to the CONSORT (CONsolidated Standards of Reporting Trials) and STROBE (Strengthening the Reporting of Observational studies in Epidemiology) statement guidelines, respectively. For data analysis, the three-dimensional accuracy and the overall implant survival rate was calculated and compared between implants placed using surgical templates with or without metallic sleeves. DATA: A total of 12 articles fulfilled the inclusion/exclusion criteria. Data from 264 patients with 614 implants were subjected to quality assessment (templates with metallic sleeves: 279 implants and 136 patients; templates without metallic sleeves: 335 implants and 128 patients). In all the three deviation parameters (angular, vertical, and horizontal), the differences in average accuracy were noticed (angular 2.33° ± 2.01° versus 3.09° ± 1.65°, vertical: 0.62 ± 0.36 [mm] versus 0.95 ± 0.42 [mm]; and horizontal: 0.62 ± 0.41 [mm] and 1.11 ± 0.57 [mm]. No differences was found regarding overall implant survival rate (0.4891). CONCLUSIONS: With the limitations of the present study, the surgical templates without metallic sleeves demonstrated high level of accuracy in all the three-dimensional measurements, when used to rehabilitate partially edentulous patients. Further randomized controlled trials, reporting according to the CONSORT guidelines are needed to confirm that the differences in accuracy depended on the type of used templates.

Role of New Hydrophilic Surfaces on Early Success Rate and Implant Stability: 1-Year Post-loading Results of a Multicenter, Split-Mouth, Randomized Controlled Trial.

OBJECTIVE: To compare early implant failure and implant stability of one-stage Hiossen ET III implants with its new hydrophilic (NH) surface, compared with Hiossen ET III implants with the sandblasted and acid-etched (SA) surface at 1-year follow-up. MATERIALS AND METHODS: This study was designed as a split-mouth, multicenter randomized controlled trial aimed to compare SA surface implants (SA group) and NH surface, (NH group). Outcomes were implant and prosthetic survival rates, complications, the insertion torque at implant placement, and implant stability quotient (ISQ) values. RESULTS: Twenty-nine patients (mean age 59.9 ± 11.3 years) were treated and followed up to 1 year after loading. No patient dropped out. Fifty-eight implants (29 SA group and 29 NH group) were placed. No implants or prostheses failed and no complications were experienced during follow-up. The mean insertion torque was 40.5 ± 3.23 (38.17-41.83) Ncm in the SA group and 40.48 ± 3.49 (38.02-41.98) Ncm in the NH group (p = 0.981). There was a statistically significant difference at the second week (T2) with higher values in the NH group (p = 0.041). Similar results were found in the maxilla (p = 0.045), but not in the mandible (p = 0.362). A positive correlation was found between initial insertion torque and ISQ with higher value in the NH group (0.73 vs. 0.66). CONCLUSIONS: NH implants are a viable alternative to SA surface, as they seem to avoid the ISQ drop during the bone remodeling phase.

Histological and Histomorphometric Evaluation of Post-Extractive Sites Filled with a New Bone Substitute with or without Autologous Plate Concentrates: One-Year Randomized Controlled Trial.

The purpose of the present study was to evaluate the histological and histomorphometric characteristics of post-extraction sites grafted with decellularized bovine compact bone from bovine femur, mixed and unmixed with leukocyte- and platelet-rich fibrin after four months of healing. This study was designed as a randomized controlled trial of parallel groups. Patients in need of a single, implant-supported restoration to replace a hopeless tooth were recruited for tooth extraction and implant placement four months after socket preservation procedure. After tooth extraction, patients were randomly allocated to receive decellularized bovine compact bone from bovine femur, mixed and unmixed with leukocyte- and platelet-rich fibrin. After four months of healing, tapered implants were inserted with an insertion torque between 35 and 45 Ncm. Two months later, implants were loaded with screw-retained definitive crowns. Outcome measures were implant (ISR) and prosthesis (PSR) survival rates, complications, histological and histomorphometric analyses, radiographic marginal bone-level changes, and patients' satisfaction. Clinical data were collected up to one year after tooth extraction and socket preservation procedures. Thirty patients were consecutively enrolled in the trial (15 in each group). Unfortunately, due to the COVID-19 pandemic, bone samples were collected only in 19 patients. Two implants failed before definitive prosthesis delivery (ISR 93.3%). No prosthesis failed (PSR 100%). Three complications were experienced in the control group. The mean bone percentage was 40.64 ± 18.76 in the test group and 33.40 ± 22.38 in the control group. The difference was not statistically significant (p = 0.4846). The mean soft tissue percentage was 32.55 ± 19.45 in the test group and 55.23 ± 17.64 in the control group. The difference was statistically significant (p = 0.0235). The mean residual graft was 24.59 ± 18.39 in the test group and 11.37 ± 12.12 in the control group. The difference was not statistically significant (p = 0.0992). Mean marginal bone loss, as well as patient satisfaction, showed no differences between groups. With the limitations of the present study, socket preservation with L-PRF mixed with decellularized bovine compact bone demonstrated favorable results, comparing with decellularized bovine compact bone from bovine femur alone. Further studies with larger sample size and longer follow-up are needed to confirm these preliminary results.

1-Year Evaluation of OT Bridge Abutments for Immediately Loaded Maxillary Fixed Restorations: A Multicenter Study.

OBJECTIVE: Preliminary data on survival and success rates of immediately loaded, maxillary, screw-retained, implant-supported, fixed restorations delivered on narrow and low-profile OT Equator abutments (OT Bridge, Rhein'83) were evaluated. MATERIALS AND METHODS: This retrospective study evaluated data collected from patients rehabilitated with OT Bridge prosthetic concept between November 2017 and February 2019 in six different centers. Outcome measures were implant and prosthetic survival rates, biological and technical complications, marginal bone loss (MBL), oral health impact profile (OHIP), bleeding on probing, and plaque index. RESULTS: A total of 76 implants were inserted in 14 patients. Patients were followed for a mean period of 15.8 months (range = 12-24). All the patients receive OT Equator (Rhein'83) as intermediate abutments. One year after loading, one implant failed (1.3%). None of the prosthesis failed. One prosthetic complication was experienced in one patient. Three out of 76 implants were connected to the prosthetic framework using only the Seeger system, without screw. Difference in OHIP values was statistically significant (71.9 ± 8.5; p = 0.000). One year after loading, MBL was 0.21 ± 0.11 mm and p-value was 0.000. One year after loading, 8.7% of the examined implant sites present positive bleeding on probing, while 6.4% of the implant sites presented plaque. CONCLUSION: The OT Equator abutments (Rhein'83) showed successful results when used to support maxillary fixed dental prosthesis delivered on four to six implants. High implant and prosthetic survival rates, very low complications, high patient satisfaction, and good biological parameters, including only 0.2 mm of bone remodeling were experienced one year after function. Further studies are needed to confirm these preliminary results.

Coronavirus Disease 2019 Coexistence in the Daily Practice.

The purpose of the present narrative review was to evaluate and discuss the actual available information regarding coronavirus disease 2019 and dental practice, and to share recommendations with the intent to help dentists in providing a safe and healthful workplace during pandemic. A step-by-step workflow is presented including prevention and measures to reduce risk for cross infections before, during, and after the dental treatments. Individualization of different risk-level zones and the establishment of a team-based chain control is also presented. The present manuscript may offer deeper knowledge and discussion regarding recommended procedures aimed to reduce risk for dental health care workers contamination and cross infections. Within these, infection prevention in dental settings, respect of general rules, containment measures, proper use of the personal protective equipments (PPE), and well-organized chain control of all the staff, with definition of risk zones and specific responsibility could be an adjunctive but important step to control the spread of the disease.

Platform switching versus regular platform single implants: 5-year post-loading results from a randomised controlled trial.

PURPOSE: To compare the clinical and radiographic outcomes of platform switching (PS) and regular platform (RP) implants. MATERIALS AND METHODS: This study was designed as a randomised controlled split-mouth trial. Eighteen patients, with bilaterally missing single premolars or molars to be restored with implant-supported single crowns, were consecutively enrolled. Implant sites were randomly assigned to be treated according to the PS concept (PS group), or with matching implant-abutment diameters (RP group). A total of 36 implants were placed in healed bone, with an insertion torque between 35 and 45 Ncm, according to a one-stage protocol. All the implants were loaded with a screw-retained provisional crown 3 months after implant insertion. Definitive screw-retained single crowns were delivered 2 months later. Outcome measures were implant and prosthetic survival rates, biological and prosthetic complications, marginal bone level (MBL) changes, pocket probing depth (PPD) and bleeding on probing (BOP). Clinical data were collected at implant placement (baseline), implant loading (3 months later) and at 9, 36 and 60 months after loading. RESULTS: One patient dropped out after 4 years of follow-up. No implant failed and no prosthetic complications were recorded during the study period. One patient experienced mucosal inflammation with positive BOP (RP group) after 3 months and three patients had bilateral peri-implant mucosal inflammation with positive BOP at 6, 24 and 36 months, respectively. No other biological complications were recorded up to 60 months of follow-up. There were no statistically significant differences between groups for complications (3/18 versus 4/18; P = 1.0). Nine months after loading the mean MBL was 0.93 ± 0.26 mm (95% CI 0.81 to 1.05) for RP implants and 0.84 ± 0.23 mm (95% CI 0.73 to 0.95) for PS implants. No statistically significant difference was observed between the groups (P = 0.18). Thirty-six months after loading, the mean MBL was 1.09 ± 0.31 mm (95% CI 0.95 to 1.24) in the RP group and 1.06 ± 0.24 mm (95% CI 0.94 to 1.17) in the PS group, with no statistically significant difference between groups (P = 0.70). Sixty months after loading the mean MBL was 1.24 ± 0.39 mm (95% CI 1.05 to 1.43) in the RP group and 1.20 ± 0.21 mm (95% CI 1.01 to 1.39) in the PS group, with no statistically significant difference between the groups (P = 0.85). The mean PPD was 2.58 ± 0.58 mm (95% CI 2.32 to 2.84) in the RP group and 2.40 ± 0.72 mm (95% CI 2.21 to 2.59) in the PS group at 60 months follow-up, with no statistically significant difference between the groups (P = 0.49). The mean BOP was 0.90 ± 0.88 (95% CI 0.58 to 1.22) in the RP group and 0.93 ± 0.97 (95% CI 0.51 to 1.35) in the PS group at 60 months of follow-up, with no statistically significant difference between the groups (P = 0.85). CONCLUSIONS: Implants restored according to the PS concept and matching implant-abutment diameters showed comparable clinical and radiographic results up to 5 years after loading.

Errors in Implant Positioning Due to Lack of Planning: A Clinical Case Report of New Prosthetic Materials and Solutions.

The achievement of the optimal implant position is a critical consideration in implant surgery, as it can facilitate the ideal prosthesis design and allow adequate oral hygiene maintenance. The switch from bone-driven to prosthetic-driven implant placement, through a comprehensive diagnosis and adequate treatment plan, is a prerequisite for long-term successful implant-based therapy. The aim of the present case report is to describe a step-by-step prosthetic retreatment of a patient with primary treatment failure due to incorrect dental implant placement. Although dental implants achieve high survival rates, the success of implant prosthetic therapy significantly relies on an appropriate implant position. Malpositioned implants can cause damage to vital structures, like nerves or vessels. Moreover, improper implant positioning can result in esthetic, biological, and technical complications and can, in extreme situations, render the desired prosthetic rehabilitation impossible to achieve.

Customized 3D-Printed Titanium Mesh Developed to Regenerate a Complex Bone Defect in the Aesthetic Zone: A Case Report Approached with a Fully Digital Workflow.

Alveolar-ridge augmentation, anterior aesthetics, and digital technologies are probably the most popular topics in the dental-implant field. The aim of this report is to present a clinical case of severe atrophy of the anterior maxilla in a younger female patient, treated with a titanium membrane customized with computer-aided design/computer-aided manufacturing (CAD/CAM), simultaneous guided implant placement, and a fully digital workflow. A young female patient with a history of maxillary trauma was treated and followed-up for 1 year after implant placement. A narrow implant was inserted in a prosthetically driven position with the aid of computer-guided surgery. In the same surgical section, a customized implantable titanium mesh was applied. The scaffold was designed according to the contralateral maxillary outline in order to recreate a favorable maxillary bone volume. Finally, highly aesthetic, CAD/CAM, metal-free restorations were delivered using novel digital technologies.

Feasibility of Using a Prosthetic-Based Impression Template to Improve the Trueness and Precision of a Complete Arch Digital Impression on Four and Six Implants: An In Vitro Study.

BACKGROUND: Intraoral scanners (IOSs) in implantology represent a viable approach for single teeth or partial arches. However, when used for complete edentulous arches or long-span edentulous areas, it has been demonstrated that there is a need for improvement of IOS-related techniques. Therefore, the aim of this in vitro study was to assess the trueness and precision of a complete arch digital impression on four and six implants taken with or without a customized, prosthetic-based impression template. MATERIALS AND METHODS: Two experimental models were prepared, representative of a complete edentulous mandible restored with four and six implants with built-in scan abutments. Models were scanned with (test group, TG) or without (control group, CG) the prosthetic-based impression template. Eight scans were taken for each model. The time needed to take impressions, error, trueness, and precision were evaluated. A statistical analysis was performed. RESULTS: In the case of four implants, the time needed for the impression was 128.7 ± 55.3 s in the TG and 81.0 ± 23.5 s in the CG (p = 0.0416). With six scan abutments, the time was 197.5 ± 26.8 and 110.6 ± 25.2 s in the TG and CG, respectively (p = 0.0000). In the TG, no errors were experienced, while in the CG, 13 impressions were retaken due to incorrect stitching processes. In the four-implant impression, the mean angle deviation was 0.252 ± 0.068° (95% CI 0.021-0.115°) in the CG and 0.134 ± 0.053° (95% CI 0.016-0.090°) in the TG. The difference was statistically significant (p = 0.002). In the six-implant impression, the mean angle deviation was 0.373 ± 0.117° (95% CI 0.036-0.198°) in the CG and 0.100 ± 0.029° (95% CI 0.009-0.049°) in the TG (p = 0.000). In the TG, there were no statistically significant differences in the mean angle deviation within the group (p > 0.05), but there were in the CG. A colorimetric analysis showed higher deviations from the original model for the six-implant impression without a prosthetic template. CONCLUSIONS: Although all of the impressions exhibited deviation from the original model in the range of clinical acceptability, the prosthetic-based impression template significantly improved the trueness and precision of complete edentulous arches rehabilitated with four or six implants, making the complete arch digital impression more predictable.

Horizontal ridge augmentation using GBR with a native collagen membrane and 1:1 ratio of particulate xenograft and autologous bone: A 3-year after final loading prospective clinical study.

BACKGROUND: Cawood-Howell class IV atrophies, also known as "knife-edge" ridges, represent a serious horizontal defect, making the placement of regular implants challenging. AIM: To clinically and radiographically evaluate bone regeneration of severe horizontal bone defects with 3 years of follow-up. MATERIALS AND METHODS: This study was designed as a single cohort, prospective clinical trial. Patients having horizontal bone width of 4 mm or less in the posterior mandible or maxilla were treated with resorbable collagen membranes and a 1:1 mixture of anorganic bovine bone (ABB) and autogenous bone. Implants were inserted and loaded 7 months later. Outcomes were implant and prosthetic survival rates, any biological and prosthetic complications, horizontal and volumetric bone dimensional changes measured on cone beam computer tomography (CBCT), peri-implant marginal bone level (MBL) changes measured on periapical radiographs, plaque index (PI), and bleeding on probing (BOP). RESULTS: Eighteen patients received 55 implants. No patient dropped-out. No implant and prosthetic failures and no complications were recorded. Super imposition of pre and 7-month postoperative CBCT scans revealed an average horizontal bone gain of 5.03 ± 2.15 mm (95% CI: 4.13-5.92 mm). After 3 years, mean MBL was 1.15 ± 0.28 mm (95% CI 0.84-1.22 mm). The PI was 11.6%, and BOP was 5.2%. CONCLUSION: Within the limitations of the present study, high implant survival rate and high average bone augmentation seem to validate the use of collagen resorbable membranes with a 1:1 mixture of particulate ABB and autogenous bone for the reconstruction of Cawood-Howell class IV alveolar ridge atrophies.

Accuracy of newly developed sleeve-designed templates for insertion of dental implants: A prospective multicenters clinical trial.

BACKGROUND: The insertion of dental implants by means of computer-assisted template-based surgery is an established method. PURPOSE: To investigate the accuracy of a newly developed sleeve-designed template and to evaluate differences between maxillary and mandibular implants as well as anterior versus posterior area. MATERIALS AND METHODS: Any partially edentulous patients requiring at least one implant to be planned on three-dimensional cone beam computed tomography scan, according to a computer-assisted template-based protocol, were consecutively enrolled at two centers. Any potential implant position was considered eligible for the present trial. Outcome measures were: implant failure, complications, and accuracy. RESULTS: A total of 39 patients with 119 implants were evaluated. No patients dropped out during the study period (mean follow-up 12.4 ± 7.1 months). Three implants failed at centre two, whereas, one complication was experienced at centre one (limited access in posterior area). Differences were not statistically significant (P > .05). The mean deviations were 0.53 ± 0.46 mm (range 0.05-3.38 mm; 95% CI 0.32-0.48 mm) in the horizontal plan (mesio-distal); 0.42 ± 0.37 mm (range 0.0-1.53 mm; 95% CI 0.26-0.40 mm) in the vertical plan (apico-coronal); and 1.43 ± 1.98° (range 0.03-11.8°; 95% CI 0.31-1.01°) in angle. Differences between centers were compared using the nonparametric Mann-Whitney U test (P > .05). More accurate results were found for anterior implants in both horizontal plan and angle. CONCLUSION: This study showed good precision in all the parameters measured. The results were thus in a range equal to or better than the mean precision found in numerous clinical trials described in the literature. Posterior implants were less accurate because of the use of open sleeves template.

Do the New Hydrophilic Surface Have Any Influence on Early Success Rate and Implant Stability during Osseointegration Period? Four-Month Preliminary Results from a Split-Mouth, Randomized Controlled Trial.

OBJECTIVE: The objective of this study is to compare the implant stability of Hiossen ET III implants with its new hydrophilic (NH) surface and Hiossen ET III implants with the sandblasted and acid-etched (SA) surface. MATERIALS AND METHODS: Patients required at least two teeth to be rehabilitated with a fixed, implant-supported restoration, consecutively enrolled. Patients randomly received SA surface implants (SA group) or SA implants with a newly developed bioabsorbable apatite nanocoating (NH group). Outcome measures were implant and prosthetic survival rate, complications, insertion torque, and implant stability quotient (ISQ) measured at implant placement and every week up to 8 weeks after implant placement. Comparison between groups was made by unpaired t-test, while the comparison between each follow-up will be made by paired t-tests to detect any change during the follow-up. Complications and failures were compared using Fisher's exact test. RESULTS: A total of 14 patients were treated with 28 implants (14 SA and 14 NH). No implant and prosthesis failed 4 months after implant placement. No complications were experienced. At the 2nd week after implants placement, two implants in the SA group showed discontinuous measurements versus none in the NH group (p = 0.4815). Implants unscrewed during ISQ measurements and were rescrewed. Data recording stopped for 6 weeks. Both implants osseointegrated without any further complication. The NH implants did not show physiological ISQ decrease between 2nd and 4th week after implant placement, showing a more even pattern of ISQ values compared with SA implants (77.1 ± 4.6 vs. 72.9 ± 11.5; difference: 4.2 ± 12.1; p = 0.258). High ISQ values were found in both groups at each time point. CONCLUSIONS: NH implants are a viable alternative to SA surface, as they seem to avoid the ISQ drop during the remodeling phase.

Accuracy of computer-assisted template-based implant placement using conventional impression and scan model or intraoral digital impression: A randomised controlled trial with 1 year of follow-up.

PURPOSE: To compare accuracy and complications of computer-assisted template-based implant placement using conventional impression and scan of a physical stone cast or intraoral scanning to rehabilitate partially edentulous patients. MATERIALS AND METHODS: Any partially edentulous patients with at least five residual teeth, requiring at least one implant to be planned on three-dimensional (3D) cone beam computed tomography (CBCT) scan according to a computer-assisted template-based protocol were enrolled. Patients were randomised according to a parallel-group design into two arms: intraoral digital impression (fully digital group) or conventional impression and scan model (conventional group). Implants were placed flapless or with a minimally invasive flap, and conventionally loaded after 5 months. Outcome measures were implant and prosthetic success, complications, accuracy and peri-implant marginal bone loss. Three deviation parameters (angular, horizontal and vertical) were defined to evaluate the discrepancy between the planned and placed implant positions. Results were compared using a mixed-model repeated-measures analysis of variance (α = 0.05). RESULTS: Twenty patients (11 females and 9 males; mean age 44.6 years old) were randomised to the fully digital group (10 patients with 28 implants) or conventional group (10 patients with 29 implants). No patients dropped out. No implant or prosthesis failed up to 1 year after loading. One implant in the fully digital group was placed freehand due to limited inter-arch space. No biological or mechanical complications were experienced during follow-up. Difference between groups were not statistically significant (P = 0.999). The mean error in angle was 2.25 ± 1.41 degrees (range 0.30 to 5.00 degrees; 95% CI: 1.38 to 3.12 degrees) in the fully digital group and 2.10 ± 1.18 degrees (range 0.30 to 5.80 degrees; 95% CI: 1.37 to 2.83 degrees) in the conventional group. The difference was not statistically significant (-0.15 ± 1.63 degrees; range -3.20 to 2.90 degrees; 95% CI: -0.87 to 0.57 degrees; P = 0.668); in the horizontal plane (mesio-distal), the mean error was 0.52 ± 0.30 mm (range 0.10 to 1.10 mm; 95% CI: 0.33 to 0.70 mm) in the fully digital group and 0.44 ± 0.26 mm (range 0.10 to 0.90 mm; 95% CI: 0.27 to 0.60 mm) in the conventional group. The difference was not statistically significant (-0.08 ± 0.38 degrees; range -1.0 to 0.60 degrees; 95% CI: -0.32 to 0.16 degrees; P = 0.279); in the vertical plane (apico-coronal), the mean error was 0.58 ± 0.44 mm (range 0.00 to 1.60 mm; 95% CI: 0.31 to 0.85) in the fully digital group and 0.46 ± 0.34 mm (range 0.00 to 1.20 mm; 95% CI: 0.25 to 0.67) in the conventional group. The difference was not statistically significant (-0.12 ± 0.59 degrees; range -1.20 to 1.00 degrees; 95% CI: -0.49 to 0.24 degrees; P = 0.250). One year after loading, the mean marginal bone loss was 0.14 ± 0.12 mm (range -0.10 to 0.40 mm; 95% CI: 0.07 to 0.21 mm) in the fully digital group and 0.18 ± 0.13 mm (range -0.10 to 0.60 mm; 95% CI: 0.09 to 0.26 mm). The difference was not statistically significant (-0.04 ± 0.19 mm; range -0.50 to 0.30 mm; 95% CI: -0.16 to 0.08 mm; P = 0.294). CONCLUSIONS: With the limitations of the present trial, implant rehabilitations planned using intraoral digital impressions showed similar results compared to conventional impression and scan model. Digital impression may be a viable option for the rehabilitation of partial edentulous patients when computer-guided template-assisted implant placement is used.

Sinus augmentation grafting with anorganic bovine bone versus 50% autologous bone mixed with 50% anorganic bovine bone: 5 years after loading results from a randomised controlled trial.

PURPOSE: To compare the outcomes of implants inserted in maxillary sinuses augmented with 100% anorganic bovine bone (ABB) grafts versus mixed with 50% ABB and 50% autologous bone graft using a lateral window approach. MATERIALS AND METHODS: This study was designed as a randomised controlled trial of parallel groups. Patients in need of an implant-supported prosthesis in maxillary posterior areas, with a residual alveolar bone height ranging between 0 and 4 mm, were recruited for lateral sinus grafting and implant placement. Patients were randomly allocated to receive two different graft materials according to a parallel group design: group A was grafted with 50% ABB and 50% autogenous bone; group B was grafted with 100% ABB. After 7 months, tapered implants were inserted with an insertion torque between 20 and 45 Ncm. Three months later implants were loaded with screw-retained temporary crowns. Definitive crowns were delivered after 3 months. Outcome measures were implant and prosthesis survival rates, complications, radiographic marginal bone-level changes, probing pocket depths (PPDs) and bleeding on probing (BOP). Clinical data were collected at definitive prosthesis delivery, and 1, 2 and 5 years after definitive loading. RESULTS: Thirty-two consecutive patients were treated with 32 sinus elevation procedures (16 group A, 16 group B). A total of 46 implants were inserted. One patient (with two implants) dropped out in group A, and two patients (with three implants) dropped out in group B. No implant/crown failed by the end of the study. Three complications (one sinus membrane perforation and two chipping of the ceramic) were observed in three patients in group A, versus none in group B (relative risk was 0.81; 95% CI 0.64-1.03; P = 0.225). At the 2-year follow-up, the mean marginal bone loss was 1.18 ± 0.50 mm (95% CI 0.95-1.45 mm) in group A and 1.28 ± 0.48 mm (95% CI 0.97-1.43 mm) in group B, with no statistically significant differences between the two groups (difference 0.11 ± 0.22 mm; 95% CI -0.06-0.16 mm; P = 0.586). At the 5-year follow-up, the mean marginal bone loss was 1.37 ± 0.48 mm (95% CI 1.13-1.86 mm) in group A and 1.42 ± 0.48 mm (95% CI 1.17-1.90 mm) in group B (difference 0.15 ± 0.08 mm; 95% CI 0.10-0.22 mm; P = 0.426). At the 2-year follow-up, the mean PPD value was 2.70 ± 0.39 mm for group A and 2.54 ± 0.66 mm for group B, with no statistically significant difference between groups (difference 0.17 ± 0.39 mm; 95% CI 0.06-0.32 mm; P = 0.456). At the 5-year follow-up, the mean PPD value was 3.20 ± 0.44 mm for group A and 3.32 ± 0.49 mm for group B (difference 0.12 ± 0.43 mm; 95% CI 0.02-0.22 mm; P = 0.672). At the 2-year follow-up, the mean BOP value was 1.21 ± 0.79 for group A and 1.28 ± 0.68 for group B (difference 0.06 ± 0.49; 95% CI -0.23-0.25; P = 0.297), and at the 5-year follow-up, the mean BOP value was 1.77 ± 0.62 for group A and 1.91 ± 0.48 for group B (difference: 0.14 ± 0.51; 95% CI -0.05-0.33; P = 0.492). CONCLUSIONS: Within the limitations of this study, the present data confirm similar clinical outcomes of implants inserted in sinuses grafted with ABB versus implants inserted in sinuses grafted with mixed 50% ABB and 50% autologous bone.