Immediate and early implant loading protocols: a literature review of clinical studies

Early load mandibular hybrid prosthesis using the Ohio State University acrylic frame requiring no final impression

BACKGROUND

Although immediate/early loading protocols for dental implants have presented encouraging outcomes, immediate loading procedures may cause discomfort to the patient and may increase the possibility of damage to the surgical site during the impression procedures. The aim of this study was to describe an alternative technique to fabricate a mandibular hybrid prosthesis in three or four days without making any final impression and to evaluate the outcomes of this technique.

METHODS

Seven patients aged 41 to 71 years (mean age, 58 +/- 11) were considered for this study. Each patient received five implants for the reconstruction of the edentulous mandible. These implants were placed in the anterior region of an edentulous mandible and restored with a final mandibular hybrid prosthesis in four days using the Ohio State University (OSU) acrylic frame requiring no final impression procedure. The patients were followed up to 19 months after implant placement.

RESULTS

No implants were lost, no technical complications were observed and only minor marginal bone loss was noted after an average 15 months.

CONCLUSIONS

This clinical study shows that the OSU acrylic frame, which can easily be customized and accommodates variability in arch form, may be an alternative method to restore any edentulous mandible with an early load mandibular hybrid prosthesis.

Immediate Implant Placement After Removal of a Failed Implant: A Clinical and Histological Case Report

The purpose of this study was to evaluate the clinical success of an implant placed immediately after the explantation of a fractured blade implant. A healthy 58-year-old male nonsmoker presented with a fractured blade implant that had been subjected to biomechanical overload. A new blade implant was placed immediately after the removal of the fractured one. The new implant was placed with a composite graft of collagen gel and corticocancellous porcine bone and covered with a bioabsorbable membrane. Radiographic evaluation at 6 months postoperation showed complete bone healing. No residual bone defect was observed or probed during the uncovering phase; moreover, no mobility, pain, suppuration, or presence of peri-implant radiolucency were observed at the second-stage surgery.

Le Fort I osteotomy with interpositional graft and immediate loading of delayed modified SLActive surface dental implants for rehabilitation of extremely atrophied maxilla: a case report

PURPOSE

To describe a successful clinical case of immediate prosthetic loading of modified sandblasting and acid-etching surface ITI dental implants inserted in a grafted maxilla after Le Fort I osteotomy.

MATERIALS AND METHODS

A 59-year-old man with a severely atrophied maxilla was treated with Le Fort I osteotomy and interpositional iliac bone graft. Thirteen weeks later, 7 modified sandblasted and acid-etched surface ITI dental implants were inserted with immediate application of a screw-fixed prosthetic acrylic device kept in functional loading for 3 months until a definitive fixed prosthesis was inserted.

RESULTS

After 20-month follow-up there has been no implant failure, with minimal bone loss and healthy peri-implant soft tissues; the patient is functionally and esthetically satisfied.

CONCLUSIONS

Immediate loading of implants placed after Le Fort I osteotomy and interpositional iliac bone grafting could be an applicable protocol to rehabilitate extremely atrophied edentulous maxillas.

CAD/CAM to fabricate ceramic implant abutments and crowns: a preliminary in vitro study

BACKGROUND

This study evaluated the feasibility of fabricating implant abutments and crowns from pre-sintered feldspathic porcelain blocks using the chair-side CAD/CAM, CEREC3D((R)) system.

METHODS

Thirty-two implant analogues were divided into two groups. In the control group, prefabricated machined anatomical titanium (Ti) abutments were screw-retained to the analogues. In the test group, machined feldspathic porcelain abutments were cemented on prefabricated machined Ti links and screw-retained to the implant analogues. These feldspathic porcelain abutments were fabricated out of pre-sintered feldspathic porcelain blocks as duplicates of the abutments in the control group using the CAD/CAM, CEREC3D system. Thirty-two feldspathic porcelain crowns, also fabricated out of pre-sintered ceramic blocks, were then cemented with resin cement on all the abutments in both groups. All samples were subsequently subjected to fracture strength testing under static load. An unpaired t-test was used to compare fracture load values between the two groups.

RESULTS

The test group using feldspathic porcelain abutments and crowns showed statistically significant higher mean fracture strength than the control group with the Ti abutments and feldspathic porcelain crowns.

CONCLUSIONS

This preliminary study showed that the chair-side CAD/CAM technology can be utilized to fabricate customized ceramic abutments with their associated ceramic crowns using pre-sintered feldspathic porcelain blocks.

Immediate Loading: Three Cases with up to 38 Months of Clinical Follow-up

Since the first report describing the placement of dental implants into fresh extraction sockets, there has been an increasing interest in this technique. The advantages of immediate implant placement have been reported to include a reduction in the number of surgical interventions, potentially decreased alveolar bone resorption after tooth loss, and shorter treatment time. Appropriate indications, good surgical technique, eand the use of a prosthetic protocol have resulted in success for immediate loading and immediate implantation. Adverse patient-related factors, such as systemic health, a smoking habit, poor oral hygiene, presence of a thin biotype, or an infection in the region of the extraction, are contraindications for this treatment. Patient satisfaction is very high, and some difficulties related to the implantation site in late implantations may be eliminated. This article reports on three cases of immediate loading with up to 30 months of clinical follow-up.

Should edentulous patients be constrained to removable complete dentures? The use of dental implants to improve the quality of life for edentulous patients

BACKGROUND

Nowadays, there is some speculation among dental educators that the need for complete dentures will significantly decrease in the future and that training in their provision should be removed from the dental curriculum.

OBJECTIVE

To sensitise the reader to the functional shortcomings of complete denture therapy in the edentulous patient and present restorative options including implants to improve edentulous quality of life in these patients.

METHODS

Information retrieval followed a systematic approach using PubMed. English articles published from 1964 to 2008, in which the masticatory performance of patients with implant-supported dentures was assessed by objective methods and compared with performance with conventional dentures, were included.

RESULTS

National epidemiological survey data suggested that the adult population in need of one or two complete dentures will increase from 35.4 million adults in 2000 to 37.9 million adults in 2020. Clinical studies have showed that the ratings of general satisfaction were significantly better in the patients treated with implant overdentures post-delivery compared with the complete denture users. In addition, the implant group gave significantly higher ratings on comfort, stability and ability to chew. Furthermore, patients who received mandibular implant overdentures had significantly fewer oral health-related quality of life problems than did the conventional group.

CONCLUSION

Implant-supported dentures including either complete overdentures or a hybrid prosthesis significantly improve the quality of life for edentulous patients compared with conventional removable complete dentures. Therefore, the contemporary dental practitioner should consider other options as well as conventional removable complete dentures to restore edentulous patients.

Immediate and early loading of Straumann implants with a chemically modified surface (SLActive) in the posterior mandible and maxilla: 1-year results from a prospective multicenter study

OBJECTIVE

Immediate and early loading of implants can simplify treatment and increase patient satisfaction. This 3-year randomized-controlled trial will therefore evaluate survival rates and bone-level changes with immediately and early loaded Straumann implants with the SLActive surface.

MATERIAL AND METHODS

Partially edentulous patients >or=18 years of age were enrolled. Patients received a temporary restoration (single crown or two to four unit fixed partial denture) out of occlusal contact either immediately (immediate loading) or 28-34 days later (early loading group), with permanent restorations placed 20-23 weeks after surgery. The primary endpoint was change in crestal bone level from baseline (implant placement) to 12 months; the secondary variables were implant survival and success rates.

RESULTS

A total of 383 implants (197 immediate and 186 early) were placed in 266 patients; 41.8% were placed in type III and IV bone. The mean patient age was 46.3+/-12.8 years. Four implants failed in the immediate loading group and six in the early loading group, giving implant survival rates of 98% and 97%, respectively (P=NS). There were no implant failures in type IV bone. The overall mean bone level change from baseline to 12 months was 0.77+/-0.93 mm (0.90+/-0.90 and 0.63+/-0.95 mm in the immediate and early groups, respectively; P<0.001). However, a significant difference in implantation depth between the two groups (P<0.0001) was found. After adjusting for this slight difference in initial surgical placement depth, time to loading no longer had a significant influence on bone-level change. Significant influence was found for: center (P<0.0001), implant length (P<0.05) and implant position (P<0.0001). Bone gain was observed in approximately 16% of implants.

CONCLUSIONS

The results demonstrated that Straumann implants with the SLActive surface are safe and predictable when used in immediate and early loading procedures. Even in poor-quality bone, survival rates were comparable with those from conventional or delayed loading. The mean bone-level change was not deemed to be clinically significant and compared well with the typical bone resorption observed in conventional implant loading.

Early loading of mandibular full-arch bridges screw retained after 1 week to four to five Monotype® implants: 3-year results from a prospective multicentre study

OBJECTIVES

This prospective multicentre study provides clinical experience up to 3 years to support a simplified treatment for mandibular edentulism within 1 week by using one-stage implant surgery and a screw-retained full-arch bridge.

METHODS

Two hundred and fifty ITI Monotype^® implants were installed in 62 patients out of 66 patients; 60 patients got four implants each and two got five implants. After 1 week, a final bridge was in function. Radiographs were taken as baseline for vertical bone loss up to 3 years post-loading for the whole cluster and specific effects of gender, centre, age, bone class, implant length over time were compiled. Clinical (mPI, SBI) and subjective parameters such as general oral hygiene and patient satisfaction were recorded and repeated at specified intervals up to 3 years.

RESULTS

Four patients were excluded at surgery and are not involved in the follow-ups. At 1 year, 61 patients (244 implants) were evaluable and all bridges were in function. After 3 years, 49 patients (194 implants) came to control. Eight patients died during the follow-up period. Three patients lost one implant each. The cumulative implant survival rate was 98.55% and the success rate for the prosthesis was 100%. As calculated from measurable radiographs, the mean bone level at baseline was 1.63±0.78 and at 1 and 3 years 2.50±0.60 and 2.56±0.74, respectively. Using the mixed model analysis and Friedman test, the time in situ, centre and bone class had significant effect on the bone resorption and to some small extent even, the implant length. Gender and age were unaffected. Oral hygiene and patient satisfaction of the treatment were improved.

CONCLUSIONS

The results indicate that one-part self-tapping sandblasted, large-grit, acid-etched (SLA) implants are suitable for loading within 1 week. In the whole period, the mean bone crestal resorption was <1 mm, which is in agreement with other similar studies.

The management of a completely edentulous patient using simultaneous maxillary and mandibular CAD/CAM-guided immediately loaded definitive implant-supported prostheses: a clinical report

Functional rehabilitation of a completely edentulous patient with removable prostheses is a clinical challenge. A patient with an edentulous maxilla and mandible received 6 endosseous implants in the maxilla and 5 implants in the mandible using CAD/CAM surgical templates. Definitive maxillary and mandibular implant-supported fixed complete dentures were connected immediately after implant placement using a CAD/CAM-guided implant surgical placement protocol.

Early loading of mandibular full-arch bridges screw retained after 1 week to four to five Monotype implants: 3-year results from a prospective multicentre study

OBJECTIVES

This prospective multicentre study provides clinical experience up to 3 years to support a simplified treatment for mandibular edentulism within 1 week by using one-stage implant surgery and a screw-retained full-arch bridge.

METHODS

Two hundred and fifty ITI Monotype implants were installed in 62 patients out of 66 patients; 60 patients got four implants each and two got five implants. After 1 week, a final bridge was in function. Radiographs were taken as baseline for vertical bone loss up to 3 years post-loading for the whole cluster and specific effects of gender, centre, age, bone class, implant length over time were compiled. Clinical (mPI, SBI) and subjective parameters such as general oral hygiene and patient satisfaction were recorded and repeated at specified intervals up to 3 years.

RESULTS

Four patients were excluded at surgery and are not involved in the follow-ups. At 1 year, 61 patients (244 implants) were evaluable and all bridges were in function. After 3 years, 49 patients (194 implants) came to control. Eight patients died during the follow-up period. Three patients lost one implant each. The cumulative implant survival rate was 98.55% and the success rate for the prosthesis was 100%. As calculated from measurable radiographs, the mean bone level at baseline was 1.63+/-0.78 and at 1 and 3 years 2.50+/-0.60 and 2.56+/-0.74, respectively. Using the mixed model analysis and Friedman test, the time in situ, centre and bone class had significant effect on the bone resorption and to some small extent even, the implant length. Gender and age were unaffected. Oral hygiene and patient satisfaction of the treatment were improved.

CONCLUSIONS

The results indicate that one-part self-tapping sandblasted, large-grit, acid-etched (SLA) implants are suitable for loading within 1 week. In the whole period, the mean bone crestal resorption was <1 mm, which is in agreement with other similar studies.

The management of a severely resorbed edentulous maxilla using a bone graft and a CAD/CAM-guided immediately loaded definitive implant prosthesis: a clinical report

Functional reconstruction of an occlusion with severe residual ridge resorption is a clinical challenge. Removable prostheses are unsuccessful in situations with severe bone resorption. A patient with an edentulous maxilla received bone grafts from the anterior iliac crest to augment the maxillary alveolar residual ridges. The maxilla underwent bilateral sinus lift in the posterior area and onlay bone graft on the anterior maxilla using platelet-rich plasma. Eight endosseous implants were placed using a CAD/CAM surgical template approximately 6 months after the bone augmentation procedure. A prefabricated definitive implant-supported fixed complete denture was connected immediately after implant placement using a CAD/CAM-guided surgical implant placement protocol.

Immediate rehabilitation of the mandible with fixed full prosthesis supported by axial and tilted implants: interim results of a single cohort prospective study

PURPOSE

The aims of this prospective study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants for the rehabilitation of the mandible and to compare the outcome of axial versus tilted implants.

MATERIALS AND METHODS

Sixty-two patients (34 women and 28 men) were included in the study. Each patient received a full-arch fixed bridge supported by two axial implants and two distal tilted implants (All-on-Four, Nobel Biocare AB, Göteborg, Sweden). Loading was applied within 48 hours of surgery. Patients were scheduled for follow-up at 6, 12, 18, and 24 months, and annually up to 5 years. At each follow-up, plaque level and bleeding scores were assessed; moreover, patient's satisfaction for aesthetics and function was evaluated by a questionnaire. Radiographic evaluation of marginal bone level change was performed at 1 year.

RESULTS

The overall follow-up range was 6 to 43 months (mean 22.4 months). Forty-four patients were followed for a minimum of 1 year. No implant failures were recorded to date, leading to a cumulative implant survival and prosthesis success rate of 100%. Plaque level and bleeding scores showed progressive decrease over time, parallel to increase of satisfaction for both aesthetics and function. No significant difference in marginal bone loss was found between tilted and axial implants at 1-year evaluation.

CONCLUSION

The present preliminary data suggest that immediate loading associated with tilted implants could be considered a viable treatment modality for the mandible.

Influence of defect depth on resonance frequency analysis and insertion torque values for implants placed in fresh extraction sockets: a human cadaver study

BACKGROUND

Clinical studies show promising outcomes with implants inserted at the time of extraction. However, this often results in an initial bone defect at the marginal region which preferably should heal for an optimal function. Therefore, monitoring of these implants is vital.

PURPOSES

The aims of this study were to determine the initial stability of implants placed into fresh extraction sockets, and to explore the correlations between the peri-implant bone levels and implant stability parameters.

MATERIALS AND METHODS

Six human cadaver mandibles including all natural teeth were selected for this study. All natural teeth were gently extracted, and 84 implants were immediately placed into fresh extraction sockets with five different implant depths. The maximum insertion torque values were recorded, and primary implant stability measurements were performed by means of resonance frequency analysis (RFA). The vertical distance between implant/abutment junction and the first bone-implant contact was recorded using a periodontal probe.

RESULTS

It was found that the insertion torque and RFA were 28.9 +/- 7 Ncm and 65.6 +/- 9 implant stability quotient (ISQ), respectively, for 420 measurements from all 84 implants. Statistically significant correlation was found between insertion torque and ISQ values (r = 0.86; p < .001) for all implants. Both insertion torque and ISQ values dramatically decreased when the amount of peri-implant vertical bone defect increased.

CONCLUSION

The results of this study demonstrated a linear relationship between peri-implant vertical bone defect depth and RFA value. It is proposed that the RFA method is sensitive to detect changes of the marginal bone level and may be used to monitor healing of peri-implant bone defects.

Immediate functional loading of single-tooth TiO2 grit-blasted implant restoration. A controlled prospective study in a porcine model. Part II: Histology and histomorphometry

BACKGROUND

Evidently, there is a fast-moving shift from delayed to immediate implant loading. The hypothesis to be tested was that bone reactions adjacent to single TiO2-microthreaded implants exposed to immediate masticatory loading for 10 weeks after placement would modulate osseointegration.

MATERIALS AND METHODS

Cylindrical- and tapered-designed implants (Astra Tech AB, Mölndal, Sweden) replaced first and third mandibular premolars respectively in 12 pigs. The animals were allocated into two groups based on soft and hard diet feeding. Each animal received, at random positions, four different masticatory loading conditions: implant with either (1) a cover screw only, (2) a healing abutment, (3) an implant with a crown without occlusal contact, or (4) an implant with a crown in contact with the antagonistic teeth.

RESULTS

Histomorphometry showed that there were no statistically significant differences in bone-implant contact (BIC), bone mass inside/outside of the threads and soft tissue ingrowth ratio for all the implants at 10 weeks after placement irrespective of masticatory loading condition. Bone loss showed a trend of progressive increase for implants with a healing abutment toward implants with occlusal contact.

CONCLUSIONS

The results of this study rejected the hypothesis and could be explained by the fact that grit-blasted acid-etched implants were already placed in dense bone.

Immediate implant loading: current status from available literature

The introduction of osseointegrated implants in dentistry represents a turning point in dental clinical practice. Thanks to their multiple therapeutic possibilities and the high predictability of success, implant therapy is now regarded as an extremely reliable approach to replace missing teeth. The concept of immediate implant loading has recently become popular due to less trauma, reduced overall treatment time, decreased patient's anxiety and discomfort, high patient acceptance and better function and esthetics. Nonetheless, research and understanding in this area are confuse and sometimes contradictory. Hence, it is the purpose of this review to provide rational for immediate implant loading, summarize current available literature, and analyze factors that influencing this newly introduced treatment method. Results from this review indicated that immediate implant loading achieved similar high success rate as that noted in the conventional approach (delayed protocols). However, a careful case selection, proper treatment plan, meticulous surgery and proper design of prosthesis are essential for optimal outcomes when this approach is adopted.

Immediate Loading of Two Implants Supporting a Ball Attachment-Retained Mandibular Overdenture: A Prospective Clinical Study

BACKGROUND

A prospective clinical study was conducted to evaluate clinically and radiographically the performance of two implants immediately loaded supporting a ball attachment-retained mandibular overdenture.

MATERIALS AND METHODS

Seventeen completely edentulous patients were included in the study. Each patient received two implants inserted after a minimal flap reflection and no vestibular extension in order to reduce the postoperative swelling and facilitate immediate prosthesis connection. After implant placement, a mandibular complete denture was connected to the implants using ball attachments of appropriate height according to the depth of the peri-implant tissue. Patients were asked not to remove the denture for 1 week. No limitations to chewing function were given. At implant placement, the maximum value of insertion torque was recorded. Patients were examined at 1, 2, 4, 12, and 52 weeks postsurgery. At postoperative visit, occlusion was checked and the need for any prosthesis maintenance was recorded. The radiographic bone level (RBL) change was measured on periapical radiographs at baseline and 12 months after loading.

RESULTS

After 12 months of loading, no implant failure was reported and the survival rate was 100%. Average RBL change was 0.7 mm +/- 0.5 mm. Of the 17 cases, two had major prosthetic complications and five patients required minor extra maintenance appointments.

CONCLUSIONS

The immediate loading of two implants by means of ball attachment-retained mandibular complete denture may be a predictable treatment option. This clinical approach offers increased stability and comfort, while keeping a high implant success rate.

CAD/CAM-guided implant surgery and fabrication of an immediately loaded prosthesis for a partially edentulous patient

The treatment planning, placement, and restoration of dental implants for the partially edentulous patient can be challenging. Anatomical limitations can make implant location difficult to determine. The use of CT scans and surgical planning software to produce a CAD/CAM surgical template, as well as the use of a flapless surgical technique, can make implant placement more predictable, safer, and easier for patients. The article describes a computer-guided surgical technique for the partially edentulous patient, with a restoration fabricated prior to implant placement, for immediate loading.

Dental Implants for Immediate Fixed Restoration of Partially Edentulous Patients: A 1-Year Prospective Pilot Clinical Trial in Periodontally Susceptible Patients

BACKGROUND

The aim of this study was to evaluate the survival of dental implants in periodontally susceptible patients using immediate loading/restoration (ILR) protocols and the factors that modulate this response.

METHODS

Systemically healthy patients who were treated previously for chronic periodontitis and who required implant therapy were recruited. Following data collection, "surgical templates" and provisional fixed restorations were fabricated. Transgingival implants were inserted, and surgical measurements were performed. After abutment connection, the crown/bridge was relined and cemented. Patients were monitored for 12 months, at which time final measurements were performed.

RESULTS

Twenty patients (49 implants) completed this study; five implants failed and were removed (90% survival rate). All implants were removed during the first 6 months. At 12 months, the mean implants' probing depth was 2.87 +/- 0.9 mm. The mean electronic mobility testing device value (-1.3 +/- 0.7) was slightly higher than at baseline (-3.53 +/- 10.7). Radiographic bone loss ranged between -1.24 and 2.77 mm (mean +/- SD: 0.91 +/- 0.2 mm). All of the implants (16) that were inserted in the premolar region were successful, whereas three of nine implants in the molar region and two of 24 implants in the canine/incisor region failed (P = 0.0278). Survival in the immediately loaded group (83%) was slightly lower than in the immediately restored group (96%); however, these differences did not reach statistical significance. None of the other variables (smoking, arch, stability, implant length and diameter, and bone width) affected the outcome of this procedure.

CONCLUSIONS

ILR protocols are predictable alternatives in periodontally susceptible patients. Results in the molar regions suggested that careful consideration should be given to implants placed in these sites. Long-term success in these patients has not been addressed.

Immediate/early function with tapered implants supporting maxillary and mandibular posterior fixed partial dentures: Preliminary results of a prospective multicenter study

STATEMENT OF PROBLEM

While immediate loading in the interforaminal area of the mandible is a documented procedure, there are limited scientific data for immediate/early loading in premolar and molar areas where less bone density is often found and functional loading is high.

PURPOSE

The purpose of this study was to evaluate if there is a difference between immediate and early loading in premolar and molar areas of the mandible and maxilla and compare data to historic data.

MATERIAL AND METHODS

Fifty-one patients received 120 tapered implants in premolar and molar areas of the mandible and maxilla, for a total of 54 short-span (2 to 4 units) fixed partial dentures. Patients with noncontrolled diseases, periodontal pathology, bruxism, and heavy smokers (more than 10 cigarettes a day) were excluded. Patients were divided into 2 groups, with placement of provisional fixed partial prostheses occurring within 24 hours (n=33) or 6 weeks (n=21) after implant surgery. The provisional prostheses had narrow, flat occlusal surfaces to reduce lateral contacts. Surgery was performed with flap elevation, a surgical guide was used, and sites with bone with lower density were underprepared. Implant insertion torque values were between 35 and 45 Ncm. After 6 months, definitive metal-ceramic prostheses were placed. Patients were monitored clinically and radiographically for marginal bone remodeling at baseline, and 3, 6, and 12 months after loading. All patients were followed for 1 year. Data were analyzed with descriptive statistics.

RESULTS

No implant failure occurred. Mean marginal bone resorption (SD) was 1.24 (0.88) mm for the immediate loading group and 1.19 (1.01) mm for the early loading group after 1 year.

CONCLUSIONS

The preliminary results demonstrate that if accurate surgical and prosthetic protocols are followed, immediate and early function are predictable and safe approaches even in premolar and molar areas with low bone density.

Clinical performance and radiographic evaluation of a novel single-piece implant in a private practice over a mean of seventeen months

STATEMENT OF PROBLEM

A novel 1-piece implant is designed to provide for stable soft tissue, immediate function, and immediate placement in fresh extraction sockets. The purported advantages include less discomfort for the patient, shorter procedure time, and a reduced number of visits as compared to conventional procedures. Clinical documentation is needed to determine whether these advantages can be realized.

PURPOSE

The aim of this study was to evaluate the clinical performance and early bone remodeling of the novel 1-piece implant in 1 private general practice. The research hypothesis was that it is possible to achieve similar clinical results using a 1-piece implant instead of the conventional 2-piece implant system with a simpler and more patient-pleasing protocol.

MATERIAL AND METHODS

Ninety-two implants, restoring both single teeth and partially edentulous situations, in 58 consecutively treated patients (35 women and 23 men, between the ages of 21 and 78), were included. Retrospective data on implant position, implant size, bone quality, and baseline radiographs was obtained from patient records, and 46 patients attended an additional prospective follow-up visit at 12 months or longer. Data were analyzed with descriptive statistics.

RESULTS

No implant failure occurred. After a mean of 17 months the average bone level was positioned at the first thread, which is in accordance with observations for other implants. In general, healthy soft tissue and favorable esthetic outcomes were observed.

CONCLUSIONS

The favorable implant survival rate and stable bone level together with the esthetic and soft tissue outcomes indicate that this novel 1-piece implant is a viable treatment option. The data support the hypothesis that it is possible to achieve similar clinical results using a 1-piece implant system instead of a 2-piece implant system with a simpler and more patient-pleasing clinical protocol.

Prospective multicenter study of marginal bone level and soft tissue health of a one-piece implant after two years

STATEMENT OF PROBLEM

A novel 1-piece implant purported to provide for stable tissue support, immediate function, and immediate placement in extraction sockets has been developed. Stabilization of the marginal bone level over time requires documentation.

PURPOSE

The aim of this study was to evaluate marginal bone level differences and soft tissue health between the 1- and 2-year follow-up of a 1-piece implant design.

MATERIAL AND METHODS

Eighty-two implants, restoring both single teeth and multiple edentulous situations, in 56 consecutively treated patients, were included. Marginal bone level was evaluated on radiographs made at implant insertion, 6-month follow-up, and annually thereafter. At 3-, 6-month, and 1-year follow-ups, presence of plaque and the soft tissue response were evaluated using plaque and bleeding on probing indexes. The papilla index was used to determine papilla size at implant insertion with the provisional restoration in place and at the insertion of the definitive restoration. The change over time in marginal bone level was analyzed with a 1-way analysis of variance (ANOVA) paired design with time as main effect (1 to 2 years) and subjects as block effect (alpha=.05).

RESULTS

One implant failure occurred, resulting in a 98.8% cumulative survival rate (CSR) for the follow-up time of 2 years. The mean (SD) change in bone level between years 1 and 2 was 0.08 mm (1.19) (95% CI-0.30 to 0.46) (P=.68), demonstrating a stable marginal bone level. Normal implant mucosa was noted for approximately 90% of the sites at the 1-year follow-up. The mean (SD) papilla score at placement was 1.3 (0.66) and increased to 1.7 (0.67) at insertion of the definitive prosthesis.

CONCLUSIONS

The stable marginal bone level and soft tissue health observed indicate that the 1-piece implant tested has the ability to preserve both hard and soft tissue. Based on the high implant survival rate and favorable tissue response, the 1-piece implant can be recommended for clinical use.

Immediately Restored, Single-Tapered Implants in the Anterior Maxilla: Prosthodontic and Aesthetic Outcomes After 1 Year

BACKGROUND

Conventional implant protocols advocate a two-stage technique with a load-free, submerged healing period. Recent studies suggest that immediate restoration of single implants may be a viable treatment option.

PURPOSE

The purpose of this study was to evaluate prosthodontic and aesthetic peri-implant mucosal outcomes of immediately restored, Southern single-tapered implants in the anterior maxilla after 1 year.

MATERIALS AND METHODS

Participants (mean age: 43.25 years; range: 23-71 years) satisfying specified inclusion criteria were randomly allocated to conventional two-stage restoration (control group; n=14) and immediate restoration groups (test group; n =14) in a randomized controlled clinical trial. Tapered, roughened-surface Southern implants were placed using a standardized technique, and implant level bone impressions were made. Provisional screw-retained crowns, out of occlusion, were placed at second-stage surgery after 26 weeks for the conventional restoration group, and within 4 hours of implant placement for the immediate restoration group. Both groups had definitive screw-retained metal-ceramic crowns placed in occlusion 8 weeks later. Peri-implant mucosal response and papilla index were recorded 4 weeks after definitive crown placement to allow for mucosal maturation and at 1 year. Prosthodontic and aesthetic outcomes were assessed using established criteria.

RESULTS

There were no significant differences within, or between, the control and test groups for age, gender, bone quality or quantity, implant stability measurements at surgery, or implant length. There were no significant differences in the implant success rate as determined by radiographic bone loss and stability tests after 1 year. There were no significant differences in prosthodontic maintenance, peri-implant mucosal response, and papilla index between the two groups over 1 year.

CONCLUSIONS

Tapered, roughened-surface implants immediately restored with single provisional crowns at surgery and definitive crowns 8 weeks later were as prosthodontically and aesthetically successful as conventionally restored two-stage implants during the first year of service. Restoring single implants immediately with screw-retained crowns is an efficient procedure, but the short-term outcome is by no means superior to a conventional two-stage approach.

Influence of forces on peri-implant bone

Occlusal forces affect an oral implant and the surrounding bone. According to bone physiology theories, bones carrying mechanical loads adapt their strength to the load applied on it by bone modeling/remodeling. This also applies to bone surrounding an oral implant. The response to an increased mechanical stress below a certain threshold will be a strengthening of the bone by increasing the bone density or apposition of bone. On the other hand, fatigue micro-damage resulting in bone resorption may be the result of mechanical stress beyond this threshold. In the present paper literature dealing with the relationship between forces on oral implants and the surrounding bone is reviewed. Randomized controlled as well as prospective cohorts studies were not found. Although the results are conflicting, animal experimental studies have shown that occlusal load might result in marginal bone loss around oral implants or complete loss of osseointegration. In clinical studies an association between the loading conditions and marginal bone loss around oral implants or complete loss of osseointegration has been stated, but a causative relationship has not been shown.

Indications for immediate loading of implants and implant success

It was the aim of this review to compare the survival and success rates of immediately loaded dental implants with those of conventionally loaded dental implants, based on prospective controlled studies and prospective studies without controls. Studies on immediate loading were identified in the current literature by electronic and hand searches. Only clinical data on root-form or cylindrical threaded oral implants were included. For immediate loading of oral implants in the edentulous and partially dentate, mandible and maxilla controlled studies could be found. All of these studies were based on limited patient numbers. Therefore, definitive conclusions could not be drawn concerning survival and success rates of immediately loaded implants compared with conventionally loaded implants. The compilation of the current literature shows that prospective controlled studies as well as prospective studies without controls using several different approaches to immediate loading have demonstrated high implant survival and success rates. However, more high-level evidence-based studies are needed to demonstrate the relative merits of immediate loading compared with conventional loading in all potential applications.

A systematic review of marginal soft tissue at implants subjected to immediate loading or immediate restoration

OBJECTIVES

The objective of this systematic review was to critically evaluate marginal soft-tissue aspects at implants subjected to immediate loading or immediate restoration.

METHODS

An electronic Medline search from 1966 up to August 2005 was conducted to identify prospective and retrospective studies on immediate implant loading. The search strategy was complemented by hand searching in peer-reviewed journals. Studies reporting on soft-tissue aspects at implants subjected to immediate loading or immediate restoration and with a follow-up time of at least 1 year were included. Assessment of identified studies and data extraction was performed independently by two reviewers. An attempt was made to isolate and categorize studies with similar protocols in order to identify trends and relevant factors. Variables that were considered included marginal and interproximal soft-tissue stability, marginal plaque accumulation, probing depth, bleeding on probing, peri-implant mucositis and peri-implantitis.

RESULTS

From an initial yield of 581 titles, 240 articles were selected for text analysis, finally resulting in 17 studies that met the inclusion criteria. Six studies on immediate implant loading or restoration were controlled studies, whereas the remainder was prospective case series. Seven studies reported on a 1-year data, and the longest follow-up within the included studies was 4 years. The total number of patients treated within the 17 studies was 432 including a total 706 implants studied. Overall, the articles reported on many different procedures and follow-up times, time points and evaluated soft-tissue parameters varied considerably between the different articles.

CONCLUSION

Within the limits of the evaluated data it can be cautiously concluded that once immediately loaded or restored implants integrate successfully, they appear to show a soft-tissue reaction with regard to periodontal as well as morphologic aspects comparable with those of conventionally loaded implants. However, follow-up periods are generally short, number of patients and/or implants per study are few, and most studies present only limited data on peri-implant soft-tissue evaluation. More accurate long-term studies with a stronger study design (i.e., RCT) reporting more detailed on treatment and follow-up protocols are required to allow for proper comparisons and conclusions.