Immediate functional loading of implants placed with flapless surgery in the edentulous maxilla: 1-year follow-up of a single cohort study

PURPOSE: To evaluate success rates and complications of implants placed with a flapless technique and immediately loaded in fully edentulous maxillae. MATERIALS AND METHODS: Implants were placed in fully edentulous maxillae with a minimum insertion torque of 45 Ncm in underprepared sites to allow maximum stability at insertion using a flapless technique. Implants were immediately loaded. Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, and edema evaluation. Stability of individual implants was assessed both manually and with Osstell at baseline and after 12 months of loading. A single sample t test was used with a significance level of .05. RESULTS: Thirty-three consecutively treated edentulous patients received 202 implants in the maxilla. In 10 patients, 53 implants were immediately inserted in fresh extraction sockets. At implant insertion, a flap had to be elevated to control the direction of the drill in 5 patients. Three implants in 2 patients did not reach sufficient stability and were left to heal for 45 to 90 days. All restorations (21 fixed prostheses and 12 overdentures) were delivered the same day of the surgery. Twenty-six patients experienced no or slight postoperative pain; 7 experienced moderate to severe pain. No or slight edema was recorded for 19 patients and moderate to severe edema for 14 patients. Two implants failed in 2 patients but were successfully replaced the same day they were removed. No major complications occurred. Five patients experienced biologic complications, eg, peri-implantitis; 10 experienced prosthetic complications. No prosthesis failed; however, 1 patient was unsatisfied with his overdenture and requested a fixed alternative. There was a highly significant difference (P < .001) between the stability at implant insertion and after 12 months. CONCLUSION: Implants placed in the edentulous maxilla with a flapless procedure can be successfully loaded the same day of surgery.     

Outcome of oral implant treatment in partially edentulous jaws followed 20 years in clinical function

Background: Most long‐term follow‐up studies of implants in partially edentulous jaws present their outcomes as mean values of implant survival and follow‐up time, and few address the fate of the remaining teeth. Purpose: The aim of this study was to investigate the results of oral implant treatment in partially edentulous jaws after 20 years, and simultaneously to assess what happens to teeth present at the time of implant placement. Materials and Methods: Seventeen partially edentulous patients, of 27 originally treated individuals, were retrospectively reviewed after receiving implants from 1983 to 1985. The parameters studied were implant survival, prosthesis stability, marginal bone loss at teeth and implants, treatment complications, need for dental treatment, and patient’s satisfaction with the outcome. Results: The cumulative survival rate was 91%, when all 27 patients were assessed, that is, including the 10 dropouts. Of the 69 inserted and followed implants (Brånemark system®; Nobel Biocare AB, Göteborg, Sweden), six failed (8.7%) during the 20‐year period, four during the first decade, and the remaining two during the second. A majority (n=4) of the losses were due to implant fractures, two after 8 years, and two after 17 years. In all, 10 of the original fixed bridges being followed (n=24) remained in function during the entire investigation period, whereas 12 were exchanged for new constructions after an average of 7 years. The mean marginal bone loss at teeth was 0.7 mm, and at implants it was 1.0 mm. The major complication observed during the second decade was veneer material fractures, which occurred 14 times in six patients. Component loosening and abutment‐ and bridge‐locking screw fractures were the second most common problems seen, indicating material/component fatigue. Most patients were satisfied with their treatment and many mentioned that they did not think of the constructions as anything but a part of their own body. Conclusion: Over the decades, treatment of partially edentulous jaws with turned titanium implants seems to function well and to provide patients with good support for fixed short‐span bridge constructions.     

Immediate Occlusal Loading of NanoTite™ Tapered Implants: A Prospective 1‐Year Clinical and Radiographic Study

Background: During the last decade, high success rates have been reported for implants placed with immediate loading procedures, especially when bone quality and quantity provide good implant stability. In many of these studies, straight‐walled implants with moderately rough surfaces were employed. Tapered implants are becoming increasingly more popular due to standardized drilling protocols and reports of high initial primary stability. Purpose: The aim of the present prospective, single center clinical study was to evaluate surface topographical analysis and the clinical and radiographic outcomes of the NanoTite? (BIOMET 3i, Palm Beach Gardens, FL, USA) Tapered Implant when used for immediate loading of fixed prostheses and single‐tooth restorations. Materials and Methods: Forty‐two patients who needed implant treatment and met admission criteria agreed to participate in the study and were consecutively enrolled. Surgical implant placement requirements consisted of a final torque of a least 30 Ncm prior to final seating and an implant stability quotient above 55. A total of 139 NanoTite Tapered implants (112 maxillary and 27 mandibular) were placed by one investigator, and the majority of these implants (n = 77/55%) were placed in posterior regions, and in soft bone (n = 90/65%). A total of 57 prosthetic constructions were evaluated consisting of 20 single‐tooth restorations, 30 fixed partial dentures, and 7 complete, fixed maxillary restorations. Radiographs were taken at baseline and at 12 months of follow‐up. Results: Of the 139 study implants, one implant failure was declared. The overall cumulative survival rate at 1 year is 99.4%. Mean marginal bone resorption is 1.01 mm (SD 0.85) during the first year of function. Conclusion: Although limited to the short follow‐up, immediate loading of NanoTite Tapered implants seems to be a viable option in implant rehabilitation, when insertion torque of at least 30 Ncm is achieved. Further studies are needed to authenticate the finding of this study.     

Immediate function with fixed implant-supported maxillary dentures: a 12-month pilot study

STATEMENT OF PROBLEM: Immediate occlusal loading of dental implants in the edentulous mandible has proven to be an effective, reliable, and predictable procedure. There is little long-term data available on similar treatments in the edentulous maxilla. PURPOSE: The purpose of this study was to evaluate the 12-month implant survival after immediate loading of 4 to 6 implants with fixed screw-retained prostheses in edentulous maxillae. MATERIAL AND METHODS: Twenty-one patients, edentulous or with remaining teeth to be extracted in the maxilla, received 4 to 6 implants (n=111). The patients were restored with screw-retained fixed provisional prostheses supported by palladium-alloy frameworks within 24 hours after surgery. Insertion torques for implants were at least 40 Ncm. Implants, grouped as tapered or cylindrical screws, were placed in healed bone or extraction sockets. Implants were also classified as either vertical or off-angle. Definitive prostheses were placed after a mean healing time of 18 weeks. Radiographic examinations were made at the time of placement of provisional prostheses and 12 months later. Between-groups bone resorption was compared using 2-way ANOVA (alpha=.05). RESULTS: The mean follow-up time for all of the patients was 20 months (range, 13 to 28 months). The cumulative implant survival rate at the 12-month follow-up visits (after surgery) was 92.8%; the prostheses survival rate was 100%. No significant differences were found between the survival of tapered or cylindrical screw-type implants placed in postextraction sockets versus those in healed edentulous sites or between vertical and off-angle placed implants. Eight implants failed during the first 3 months, 5 of which were the most distal implants. The mean reduction in marginal bone height over the 12-month observation period was 0.84 mm (CI 95%; 0.68-0.99 mm). CONCLUSIONS: In this study with 12-month follow-up, 4 to 6 implants were sufficient to successfully support fixed implant screw-retained prostheses in the edentulous maxillae of 21 patients.     

Immediate nonocclusal versus early loading of dental implants in partially edentulous patients: 1-year results from a multicenter, randomized controlled clinical trial

PURPOSE: To compare the efficacy of immediate nonocclusal loading (test group) versus early loading (control group) in partially edentulous patients. MATERIALS AND METHODS: Fifty-two patients in 5 Italian private practices were randomized to 1 of the treatments: 25 to the immediately loaded group and 27 to the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of > 30 Ncm, and splinted implants had to be inserted with a torque of > 20 Ncm. Implants in the immediately loaded group were provided with full acrylic resin nonoccluding temporary restorations within 48 hours after placement. After 2 months, full occluding provisional restorations were provided. Implants in the early loading group were not submerged and were loaded after 2 months. At 8 months, provisional restorations were replaced with definitive metal-ceramic prostheses. Outcome measures were prosthesis and implant failures as well as biologic and prosthetic complications recorded by nonblinded assessors. The Fisher exact test was used to compare the proportion of implant failures. RESULTS: Fifty-two implants were placed in the immediately loaded group and 52 in the early loaded group. No dropouts or complications occurred up to 14 months postinsertion. One single implant failed in the immediately loaded group 2 months after placement. There was no statistically difference for the tested outcome measures between the 2 procedures (P > .99). CONCLUSIONS: The results of this randomized controlled clinical trial with 25 patients rehabilitated with immediately restored nonocclusally loaded implant-supported prostheses compared to 27 patients restored 2 months following placement suggest that there are no major clinical differences in implant survival between these 2 protocols. No biologic or prosthetic complications occurred.     

A long-term follow-up study of non-submerged ITI implants in the treatment of totally edentulous jaws. Part I: Ten-year life table analysis of a prospective multicenter study with 1286 implants

In this prospective multicenter study, non-submerged ITI implants were followed in order to evaluate their long-term prognosis in fully edentulous jaws. A total of 1286 implants were inserted in 233 consecutive patients and, after a healing period of three to six months, the successfully integrated implants were restored with 163 overdentures and 95 fixed full-arch bridges. This prospective study not only calculated the 10-year cumulative survival and success rates for the 1286 implants by life table analysis, but also evaluated the actual survival and success rates for 498 implants after at least five years of functional loading. In addition, cumulative success rates were calculated for implant subgroups according to implant length and location. Additional analyses were performed to evaluate the estimated and actual survival and success rates of the implants in relation to various prosthetic rehabilitation techniques. The 10-year cumulative survival and success rates were 95.9% and 92.7%, respectively. The actual 5-year survival and success rates of the first 498 implants that were inserted were 97.7% and 95.0%, respectively. The analysis of implant subgroups showed slightly more favourable cumulative success rates for 12 mm long implants (93%), in comparison to 10 mm and 8 mm long implants (91.6% and 89.6%, respectively). The cumulative success rate for mandibular implants (approximately 94%) was also more favourable than that for maxillary implants (approximately 91%). Patients who were loaded with both maxillary and mandibular prostheses maintained success rates well above 90%; while only implants that were inserted to support maxillary overdentures that were retained by Dolder bars showed a success rate below 90%.     

Laser-welded titanium frameworks supported by implants in the partially edentulous mandible: a 10-year comparative follow-up study

Background: Comparative long‐term knowledge of different framework materials in the partially edentulous implant patient is not available. Purpose: To report and compare 10‐year data on free‐standing implant‐supported partial prostheses with laser‐welded titanium (test) and conventional gold alloy (control) frameworks. Materials and Methods: Altogether, 52 partially edentulous patients were consecutively provided with laser‐welded prostheses (n = 60) in the partially edentulous lower jaw (test group). A control group of 52 randomly selected patients with gold alloy castings (n = 60) was used for comparison. Clinical and radiographic 10‐year data were retrospectively collected and evaluated for both groups. Results: The overall 10‐year implant cumulative survival rate (CSR) was 93.0% (loaded implants, 96.4%), with a 10‐year implant CSR of 91.5 and 94.7% for test and control implants, respectively (p > .05). Out of a total of 22 lost implants, 17 implants (77.3%) were shorter than 10 mm. The overall 10‐year prosthesis CSR was 93.7%, with a corresponding 10‐year CSR of 88.4 and 100% for test and control groups, respectively (p < .05). Average 10‐year bone loss was 0.46 mm (SD 0.47) and 0.69 mm (SD 0.53) for the test and control groups (p < .001), respectively. Only 1% of the implants had >3 mm accumulated bone loss after 10 years. Altogether, 10 of the prostheses in both groups had implant component mechanical problems (8.3%). None of the frameworks or implants fractured, but more fractures of porcelain veneers were observed in the test group (p < .05). Conclusion: The protocol of implant treatment in the partially edentulous jaw functioned well during 10 years, although prosthodontic maintenance was required. However, laser‐welded titanium frameworks presented more problems as compared with gold alloy frameworks. More loaded implants were lost (p < .05), and higher incidence of porcelain chipping was noted in the test group (p < .05). However, bone loss was on an average lower for the test group during the 10 years of follow‐up (p < .001).     

A 5‐year prospective clinical study of Astra Tech dental implants supporting fixed bridges or overdentures in the edentulous mandible

In a 5‐year prospective clinical study, 1.55 endosseous implants were installed in the mandible anterior to the mental foramina in 33 edentulous patients (13 males and 20 females). Usually 6 implants were installed for fixed prostheses (FP). 13 patients with 77 implants, and 4 implants for overdentures (OD) with a Dolder bar, 20 patients with 78 implants. At the time of abutment connection 1 implant in 2 patients was found to be loose and removed. However, in both these patients overdentures were successfully placed on the remaining 3 implants. Narrow‐beam radiography was used for radiological evaluation. The mean (SD) total marginal bone loss in 5 years was 0.48 (0.38) mm (0.36 (0.22) mm in the FP group and 0.56 (0.45) mm in the OD group). Very few complications were reported during the 5 years, most of them being related to the superstructures. The overall cumulative implant survival rate was 98.7%(100% in the FP group and 97.4% in the OD group). The survival rate of the superstructures was 100%. The present study has demonstrated that Astra Tech implants offer reliable and predictable medium‐term support for fixed prostheses and overdentures in the edentulous mandible.     

Ten‐Year Retrospective Follow‐Up Study of the TiOblast™ Dental Implant

Purpose: Long‐term results in the clinical outcome of different implant systems, including high patient numbers and a long follow‐up time, are rare. This retrospective study evaluated the cumulative survival rate of a self‐tapping, cylindrical implant system with a conical implant‐abutment connection after 10 years of prosthetic loading. Materials and Methods: A total of 516 TiOblast? implants (Astra Tech AB, Mölndal, Sweden) were placed in 108 patients. The patients were treated in the Department of Oral and Maxillofacial Surgery, Johannes Gutenberg University, Mainz, Germany, between September 1994 and May 2005. The main indications for implantation were the treatment of edentulous mandibles (74%) and partial edentulism (15%). Twenty‐three implants were placed postradiation, and a further 64 implants were irradiated after insertion. In 153 implants, a bony augmentation was conducted prior to implantation. Results: The in situ rate was 89.7% after an average implantation time of 108 months. Eighty‐three patients with 403 implants were available for investigation. Seventeen patients with 76 implants have died since 1994. Absence of osseointegration (n = 22), peri‐implantitis (n = 18), fracture of the implants (n = 9), failing of primary stability (n = 2), and implants next to tumors (n = 2) were the reasons of explantation in 26 patients. Under analysis with different implant success‐assessment criteria, the success rate showed results from 76 to 89%. Conclusion: With respect to the critical patient selection including a high number of patients with minor and major augmentations, the 10‐year clinical use of the studied implant system showed acceptable results.     

Immediately restored one-piece single-tooth implants with reduced diameter: one-year results of a multi-center study

Objectives: The aim of the present multi‐center study was to evaluate the treatment outcome of immediately restored one‐piece single‐tooth implants with a diameter of 3 mm after 1 year. Material and methods: A total of 57 one‐piece implants (NobelDirect^® 3.0) were inserted in 47 patients (26 females, 21 males) with a mean age of 31 years (range: 17–76 years) at five different centers. The implants replaced maxillary lateral incisors and mandibular incisors. The implants were placed either in conjunction with tooth extraction or in healed sites, and all implants were immediately restored with a provisional resin crown. If needed, the abutment part of the implant was prepared before crown cementation. The permanent crown was placed after 1.9–14.5 months. Radiographs were taken at implant insertion as well as after 6 and 12 months to evaluate the peri‐implant marginal bone level and bone loss. Moreover, plaque, bleeding on probing and complications were assessed. Results: A total of 44 patients (23 females, 21 males) with 54 implants were available for the 1‐year follow‐up. One implant was lost, thus the 1‐year implant survival was 98%. A statistically significant mean marginal bone loss was observed between baseline and 6 months (1.1 mm, range: ?0.7 to 4.4 mm; n=49) and between baseline and 12 months (1.6 mm, range: ?0.8 to 4.6 mm; n=50). A total of 18% of the implants were characterized by a bone loss of more than 3 mm. No bleeding on probing was observed around 83% of the implants. Plaque was registered at 15% of the implants. The most common complications were related to the provisional crown, i.e. fracture (n=3) and loss of retention (n=3). Conclusions: A high 1‐year implant survival was observed in the present study. However, the excessive peri‐implant marginal bone loss around several implants indicates that this implant should be used with caution until further studies have been conducted. To cite this article:
Zembi? A, Johannesen LH, Schou S, Malo P, Reichert T, Farella M, Hämmerle CHF. Immediately restored one‐piece single‐tooth implants with reduced diameter: one‐year results of a multi‐center study.
Clin. Oral Impl. Res. 23 , 2012; 49–54.
doi: 10.1111/j.1600‐0501.2011.02174.x     

Prospective study with a 2‐year follow‐up on immediate implant loading in the edentulous mandible with a definitive restoration using intra‐oral welding

Objectives: The aim of this prospective study was to evaluate the concept of intra‐oral welding as a suitable technique for the fabrication of a restoration for edentulous mandibles on the same day as surgery using tapered connection implants. Material and methods: Each of 20 patients had an edentulous mandible and received four inter‐foraminal, tapered connection implants. All implants were immediately loaded with a fixed restoration supported by an intra‐orally welded titanium framework. Final abutments were connected to the implants and then a titanium bar was welded to them using an intra‐oral welding unit. This framework was used as a support for the final restoration, which was fitted on the same day as implant placement. Mean marginal bone loss and radiographically detectable alteration of the welded framework were assessed using periapical radiographs immediately after surgery, and at 6‐, 12‐ and 24‐month follow‐up examinations. Results: Seven males and 13 females, with an average age of 56.5 years (SD=15.1; n=20), were consecutively treated with 80 immediately loaded implants. No fracture or radiographically detectable alteration of the welded frameworks was evident. All implants osseointegrated and a 100% implant survival rate was achieved at the 24‐month follow‐up. The accumulated mean marginal bone growth was 0.21 mm (SD 0.25, n=80). The average pocket probing depth was 1.38 mm (SD 0.41). Conclusions: The intra‐oral welding technique applied to the delivery of a final restoration of the edentulous mandible over immediately restored tapered connection implants seems to have no adverse effect on marginal bone loss and implant survival. To cite this article:
Degidi M, Nardi D, Piattelli A. Prospective study with a 2‐year follow‐up on immediate implant loading in the edentulous mandible with a definitive restoration using intra‐oral welding.
Clin. Oral Impl. Res. 21 , 2010; 379–385.
doi: 10.1111/j.1600‐0501.2009.01865.x     

Five-year results from a randomized, controlled trial on early and delayed loading of implants supporting full-arch prosthesis in the edentulous maxilla

Objectives: The overall aim was to compare the clinical outcomes of early and delayed implant loading in the totally edentulous maxilla during 5 years of function. Materials and methods: Twenty‐four patients with edentulous maxillae were randomized in two groups and subjected to early (test, n=16) or delayed (control, n=8) loading. A total of 142 implants were placed and 139 implants (Straumann AG) were loaded with full‐arch bridges and followed for 5 years. Results: All patients received and maintained a fixed bridge throughout the study period. Five (5.3%) test implants in three patients and two (4.3%) control implants in two patients were lost during the 5 years (NS). There were no differences in implant stability as measured with resonance frequency analysis at 5 years. More bone loss occurred at test than at control implants, ?0.8 mm (SD 1.2) vs. ?0.3 mm (SD 1.1), respectively. However, test implants showed a more coronal marginal bone level than control implants after 5 years, 2.9 mm (SD 1.1) vs. 3.7 mm (SD 1.2) from the implant shoulder, respectively. No control implants and four (4.4%) test implants in three (18.8%) patients showed >3 mm bone loss after 5 years. Two of the latter implants in one patient also showed increased probing depths, bleeding at probing and plaque accumulation. Tooth fracture was the most common prosthetic complication. The use of lingual gold onlay effectively reduced the number of resin‐related complications as opposed to a resilient mouth guard. Conclusions: The present randomized controlled trial showed no important differences between early and delayed loading of implants in the edentulous maxilla after 5 years of function. A favourable long‐term marginal bone response to the sandblasted large‐grit acid‐etched (SLA) surface was observed. Technical complications were mainly resin‐related which could be avoided by the use of a lingual gold onlay. It is concluded that early loading of SLA‐surface implants for support of full‐arch bridges represents a viable therapy for the totally edentulous maxilla.     

Early loading of implants with fixed dental prostheses in edentulous mandibles: 4.5‐year clinical results from a prospective study

Aim: The purpose of this study was to evaluate the survival and success of early‐loaded implants placed in the intraforaminal area of the edentulous mandible, and the survival of the implant‐supported fixed dental prostheses (FDP). Material and methods: Thirty‐seven patients (18.9% male, mean age 64.5 years) with edentulous lower jaws were treated with implant‐supported FDPs in the mandible. One hundred and eighty‐five screw‐type implants were placed in the intraforaminal area of the symphysis (five implants per patient). Immediately after implant placement, a framework was fabricated and the FDP was manufactured on the framework. Within 2 weeks, the implants were rigidly connected and loaded with the implant‐retained FDP. Results: During the 1–8‐year observation period (mean 4.5 years), a total of 32 implant‐retained complications occurred. Nineteen implants were lost in 10 patients, resulting in a cumulative survival of 89.7%. Nine implants in five patients did not osseointegrate. Although these implants were not removed, because stability within the connective tissue was acceptable and inflammation was absent, they were recorded as unsuccessful. Consequently, the cumulative success declined to 84.9%. Four implants in three patients had clinical signs of periimplantitis (2.2% of all implants). Denture‐related complications included one complete failure, when one FDP had to be removed after the last of five implants had been replaced. Furthermore, 10 fractures of the framework occurred in six patients, three FDPs had to be adapted or modified, and the facing of the FDP had to be repaired 16 times in 11 patients. Conclusion: Although one‐stage early‐loaded implants functioned well for most patients with edentulous mandibles, immediate loading is associated with a larger number of implant‐related complications than in other studies investigating delayed loading. Because of the substantial prosthetic complications and aftercare, this procedure cannot be generally recommended. To cite this article:
Schwarz S, Gabbert O, Hassel A J, Schmitter M, Séché C, Rammelsberg P. Early loading of implants with fixed dental prostheses in edentulous mandibles: 4.5‐year clinical results from a prospective study.
Clin. Oral Impl. Res. 21 , 2010; 284–289.
doi: 10.1111/j.1600‐0501.2009.01843.x     

Prospective Evaluation of 2,549 Morse Taper Connection Implants: 1‐ to 6‐Year Data

Background: The aim of this study is to evaluate the implant survival, the implant–crown success, and the prosthetic complications of 2,549 Morse taper interference–fit connection implants. Methods: A total of 2,549 Morse taper connection implants were inserted in 893 patients from January 2003 until December 2008. At each annual recall, clinical, radiographic, and prosthetic parameters were assessed. The implant–crown success criteria included the absence of pain, suppuration, and clinical mobility; an average distance between the implant shoulder and the first visible bone contact <2 mm from initial surgery; and the absence of prosthetic complications at the implant–abutment interface. Prosthetic restorations were fixed partial prostheses (462 units); fixed full‐arch prostheses (60 units); single crowns (531 units); and overdentures (93 units). Results: The cumulative implant survival rate was 98.23% (97.25% maxilla, 99.05% mandible). The implant–crown success was 92.49%. A few prosthetic complications at implant–abutment interface were reported (0.37%). After 6 years, distance between the implant shoulder and the first visible bone contact was 1.10 mm (± 0.30 mm). Conclusion: The use of Morse taper connection implants represents a successful procedure for the rehabilitation of partially and completely edentulous arches.     

Maxillary Overdentures Supported by Anteriorly or Posteriorly Placed Implants Opposed by a Natural Dentition in the Mandible: A 1‐Year Prospective Case Series Study

Background: For maxillary overdenture therapy, treatment guidelines are missing. There is a need for longitudinal studies. Purpose: The purpose of this 1‐year prospective case series study was to assess the treatment outcome of maxillary overdentures supported by six dental implants opposed by natural antagonistic teeth in the mandible. Materials and Methods: Fifty patients were treated with a maxillary overdenture supported by six dental implants, either placed in the anterior region (n = 25 patients) or in the posterior region (n = 25 patients). Items of evaluation were the following: survival of implants, condition of hard and soft peri‐implant tissues, and patients' satisfaction. Results: One‐year implant survival rate was 98% in the anterior group and 99.3% in the posterior group. Mean radiographic bone loss in the anterior and posterior groups after 1 year of loading was 0.22 and 0.50 mm, respectively. Mean scores for plaque, calculus, gingiva, bleeding, and pocket probing depth were low, and patients' satisfaction was high, with no differences between the groups. Conclusion: Six dental implants placed in either the anterior region or the posterior region of the edentulous maxilla, connected with a bar, and opposed by antagonistic teeth in the mandible supply a proper base for the support of an overdenture.     

无牙颌患者种植修复的体会

目的：探讨无牙颌种植覆盖义齿、种植固定义齿修复的临床疗效。方法：对34例单颌、全颌无牙颌患进行了种植修复。单颌无牙颌26例中10例进行了杆卡修复,5例球帽修复,2例磁性固位体修复,9例种植固定修复。全颌无牙颌8例中3例种植固定修复,3例杆卡修复,2例球帽修复。结果：经6～60个月的临床观察,256枚种植体中,除3枚种植体形成纤维愈合(1．17％)外,其余253枚种植体均形成了良好的骨性结合(98．83％),种植义齿功能较好,收到了满意的临床效果。结论：对于无牙颁的患,通过精心的设计、精巧的外科手术及合理的种植修复类型的选择,完成的种植修复体能有效地恢复咀嚼功能,并能使种植体长期稳固于口腔内行使功能。     

In-patient comparison of immediately loaded and non-loaded implants within 6 months

Abstract: According to the Brånemark protocol, a stress‐free healing period is one of the most emphasised requirements for implant integration. Recent studies have encouraged a progressive shortening of the healing period and immediate loading has been proposed for the edentulous mandible. This prospective study evaluated the clinical outcomes of 14 immediately loaded FRIALIT‐2^® implants compared with 28 non‐loaded controls in an in‐patient study. The results were based on clinical stability and on changes of bone level from implant placement to abutment connection 6 months after insertion. In the course of our investigation, seven patients with edentulous mandibles have been treated with 43 implants following an immediate‐loading protocol. Six FRIALIT‐2^® implants were placed in the interforaminal region located at positions 34, 33, 32, 42, 43, 44. Bone level in relation to implant margin was measured and recorded. In order to obtain an in‐patient comparison of immediately loaded and non‐loaded implants, the ones at 33 and 43 were chosen to be immediately loaded by a Dolder‐bar retained overdenture. The implants in position 32, 34, 42 and 44 were covered and left to heal. After a healing period of 6 months, second stage surgery was carried out. The clinical criteria to be checked at this point were survival, Periotest values and marginal bone level at the loaded and non‐loaded implants. The mean Periotest value was ?2.7 for the loaded and ?5.6 for the non‐loaded implants. The Mann–Whitney U‐test showed that the difference was highly significant (P < 0.001). The mean bone level changes at prosthetic delivery were 0.9 mm resorption for the loaded implants and 0.33 mm for non‐loaded implants. The difference was highly significant (P < 0.001). No implant failures were observed up to the prosthetic restoration 6 months post insertion. The results of this investigation allowed for direct comparison of implant survival and clinical results between immediately loaded implants and standard implants. Clinical bone changes at the 6‐month evaluation demonstrated significantly higher crestal resorption around loaded implants. This fact was confirmed by higher median Periotest values (?3 vs. ?6) of immediately loaded implants. According to the outcome of this study, immediate loading of two interforaminal implants with a Dolder‐bar resulted in an intimate bone apposition comparable with implants with submerged healing. Nevertheless, the coronal bone level as well as clinical stability (PTV) were significantly lower in the case of the immediately loaded implants. Future studies will be necessary to evaluate marginal bone resorption, Periotest values and clinical success rates of mandibular immediately loaded implants in the long‐term.     

Immediate loading of 190 endosseous dental implants: a prospective observational study of 40 patient treatments with up to 2-year data

PURPOSE: The present study was undertaken to determine the feasibility of using primary stability as a predictor of implant success in patients whose implants were immediately loaded. MATERIALS AND METHODS: The study included 40 patients, in whom a total of 190 implants were placed, 102 in maxillary sites and 88 in mandibular sites. All were loaded within 72 hours of placement. Sixteen patients were completely edentulous in the mandible and/or the maxilla. The remaining 24, who were partially edentulous, received fixed partial dentures or single-implant restorations. All of the definitive implant restorations were screw retained. The criterion for loading was clinical judgment of primary stability, verified by a "screw test." Impressions were made after implant placement to facilitate the fabrication of a laboratory-made heat-processed provisional restoration from acrylic resin. Following a 4-month period for osseointegration and soft tissue healing, definitive fixed prostheses were fabricated. RESULTS: There were no surgical complications. After 1 to 2 years, all 190 implants had survived and were considered 100% successful, as determined by independent testing of mobility and radiographic evidence of osseointegration. In 4 patients, fracture of the provisional restoration occurred during the healing period. DISCUSSION: Clinical research has shown that immediate loading is a viable treatment modality. The favorable success rate reported in this study for rough-surfaced implants suggests that adherence to a protocol, an important parameter of which is primary stability above 32 Ncm, can lead to osseointegration. CONCLUSION: The results of this limited investigation suggest that patients who are partially or completely edentulous may be immediately restored with implants and fixed provisional restorations, provided that the dental implants are adequately stable immediately after their surgical placement. This alternative therapeutic approach did not appear to affect the up-to-2-year survival of the implants in this patient population.     

部分牙缺失种植即刻功能负荷的临床探讨

目的:对部分牙缺失种植即刻功能负荷进行临床探讨。方法:将NobelBiocare种植体植入颌骨内,种植体植入扭力必须达到35Ncm以上。选择永久基台接在种植体上,用一定的扭力拧紧基台,基台水平印模,按常规制作和即刻戴上临时塑料修复体。6周后再印模,制作和戴上烤瓷修复体。结果:36例65枚种植体中,下颌22例41枚种植体,上颌14例24枚种植体,修复后成功率为98.5%。结论:部分牙缺失种植即刻功能负荷初步临床结果是满意的,其长期效果有待进一步的观察。