Implant Reconstruction of the Bone- Grafted Maxilla: Review of the Literature and Presentation of 8 Cases

Prosthodontic criteria for maxillary immediate occlusal loading, surgical classifications of atrophic maxillae, and presentation of a new implant/anatomic classification system for immediate maxillary rehabilitation

PURPOSE

Immediate full-arch occlusal loading for patients with atrophic edentulous maxillae satisfies critical needs for this specific type of edentulous patient after placement of implants with high levels of primary implant stability. The needs include improved aesthetics, limited immediate improved function, and elimination of removable prostheses. Classification systems exist for edentulous maxillae but they do not include specifics regarding posterior implant placement. In conjunction with anterior implants, posterior implants improve Anterior/Posterior (A/P) spreads, decrease cantilevered segments (CLs), and likely will improve implant and prosthetic success rates. The purposes of this article include presenting a new classification system that outlines the different types of implants now available which will likely achieve the requisite primary stability for immediate fixed rehabilitation. This proposed classification system identifies a relationship between different implant options currently available and the remaining quantity of bone in the first and second maxillary molar zones.

MATERIALS AND METHODS

The available literature regarding current classification systems was reviewed. The benefits and limitations of each system were described. The parameters associated with Immediate Occlusal Loading (IOL) for full arch maxillary prostheses include: posterior cantilever lengths of full arch fixed prostheses; existing A/P spread considerations for full arch prostheses; and introduction of a new classification system for atrophic posterior maxillary edentulous ridges were identified.

RESULTS

Currently, there are no available classification systems that outline specific implant options for posterior maxillae which will likely achieve the minimum primary stability needed for immediate rehabilitation. A new classification system was proposed where the rationale was to show clinicians that when a certain amount of bone remains in the posterior maxilla, there are specific implants designed to maximize primary stability. High implant primary stability is required for rehabilitation with immediate fixed implant-supported provisional prostheses. The proposed classification system assists clinicians in understanding what implant geometry is available and can be expected to achieve the requisite primary stability for immediate occlusal loading based on the available bone in the posterior maxillary molar zone.

CONCLUSIONS

This article reviewed current classification systems for edentulous maxillary patients, as well as clinical parameters required for full arch, immediate occlusal loading.  It also presented a new classification system to assist clinicians in selecting appropriate implants and surgical techniques for immediate fixed rehabilitation of patients with atrophic maxillae.

Study of the radiofrequency-induced heating inside the human head with dental implants at 7 T

Conductive dental implants are commonly used in restorative therapy to replace missing teeth in patients. Ensuring the radiofrequency (RF) safety of these patients is crucial when performing 7 T magnetic resonance scans of their heads. This study aimed to investigate RF-induced heating inside the human head with dental implants at 7 T. Dental implants and their attachments were fabricated and integrated into an anatomical head model, creating different measurement configurations (MCs). Numerical simulations were conducted using a 7 T transmit coil loaded with the anatomical head model, both with and without dental implants. The maximum temperatures inside the head for various MCs were computed using the maximum permissible input powers (MPIPs) obtained without dental implants and compared with published limits. Additionally, the MPIPs with dental implants were calculated for scenarios where the temperature limits were exceeded. The maximum temperatures observed inside the head ranged from 38.4°C to 39.6°C. The MPIPs in the presence of dental implants were 81.9%-97.3% of the MPIPs in the absence of dental implants for scenarios that exceeded the regulatory limit. RF-induced heating effect of the dental implants was not significant. The safe scanning condition in terms of RF exposure was achievable for patients with dental implants. For patients with conductive dental implants of unknown configuration, it is recommended to reduce the input power by 18.1% of MPIP without dental implants to ensure RF safety.

The use of monophasic implants as an alternative of implant-prosthetic rehabilitation in the posterior maxilla with no sinus lift

BACKGROUND

Over the years, numerous studies and advanced technologies about dental implants have been evolved from the traditional two-stage procedure to immediate loading. Implants located in the posterior maxillary region allow to achieve an appropriate prosthetic support. The aim of this work was to solve the atrophied posterior maxilla, through monophasic implants with flapless technique and intraoral electro-welding.

METHODS

In this study were enrolled 120 patients between 20 and 68 years old (mean age of 34.2 years), where females predominate with 53.1% compared to 46.9% males. The patients were presented at the Oral Surgery Clinic of the Aldent University (Tirana, Albania), for a period 2009-2019. Briefly, 310 monophasic implants were placed, TRAMONTE type (Milan, Italy), to the posterior maxilla thus avoiding the sinus, with dense and wide threads, of different lengths and widths. The surgical technique was minimally invasive, flapless one. Data were expressed as mean + standard error (SEM) of all the radiographic outcomes obtained; and as statistical analysis was used the Student's t-test. P<0.5 and P<0.05, were considered significant.

RESULTS

A part of the patients were hypertensive and type 2 diabetic, then a negligible part were smokers, also a lack of oral hygiene was observed in 40% of cases. After 5 years of observation, it appeared that 95.9% of the implants were successful. Furthermore, the mesial and distal bone loss during the first three years was 0.1 mm, while after 5 years no continuation of bone loss was observed.

CONCLUSIONS

The application of monophasic implants must be performed according to approved protocols, considering the conditions of the posterior maxillary region, obtaining in this way a safe dental implantation.

UV-Mediated Photofunctionalization of Dental Implant: A Seven-Year Results of a Prospective Study

Our objective was to evaluate the seven-year results of photofunctionalized implants placed in regular, complex, and cancer-related cases. This study was a prospective, single-center study. Photofunctionalization was performed immediately prior to implantation with Ultraviolet (UV) light for 15 minutes. The success rate of each patient group and the influential factors on implant failure were analyzed. Seventy implants in 16 patients were included. Four implants were left submerged (sleep). The seven-year success rate of 30 implants in regular cases and 21 implants in complex cases was 100%. The success rate of 15 implants in cancer-related cases was 22.2%, in which implants were placed in resection or reconstructed sites with or without pre- or postoperative radiation history. Implant stability quotient (ISQ) values increased at second-stage surgery by 3.2 in regular cases and by 21.9 in complex cases, while it decreased by −3.5 in cancer cases. Multivariate analysis indicated that bone quality, location, and cancer resection significantly influenced implant failure. A very reliable seven-year success rate was obtained by UV-photofunctionalized implants in regular and complex cases, even with significant site-development procedures. However, the success rate in cancer cases was significantly and remarkably lower, suggesting remaining challenges of pathophysiologically compromised conditions, such as bone resection, segmental defect, and radiation.

Technical Strategy of Bone Graft Augmentation in the Anterior Maxilla

Bone graft augmentation in the anterior maxilla has a high successful rate. However, suture dehiscence and consequent bone graft exposure can compromise and fail this procedure. Therefore, this article presents a new strategy of closure technique to guarantee the bone graft augmentation. The sutures occur in muscular and mucous planes to avoid suture tension, thus decreasing complications of bone graft augmentation in the anterior maxilla.

Comparison between peri-implant bone level changes of implants placed during and 3 months after iliac bone grafting

OBJECTIVE

The aim of this study was to compare the peri-implant bone level changes of implants placed during and 3 months after bone grafting from the iliac crest.

STUDY DESIGN

A total of 103 implants were placed: 42 during the grafting and 61 at 3 months after the grafting procedure. All patients were grafted with iliac bone from the anterosuperior iliac crest. Bone resorption was evaluated with cone beam computed tomography in all patients at their last control visit. Periodontal health was assessed via the gingival and plaque indices and pocket depths around the dental implants.

RESULTS

Mean bone resorption values at the buccal, lingual, mesial, and distal sides of the implants were 1.08 mm, 0.36 mm, 0.30 mm, and 0.25 mm, respectively, in the delayed group, and 1.87 mm, 1.25 mm, 0.92 mm, and 1.23 mm, respectively, in the simultaneous group; the differences between the groups were significant. There were no significant between-group differences in the gingival or plaque indices or pocket depths. The mean follow-up period was 29 months.

CONCLUSIONS

For reconstructing atrophic jaws, bone grafting from the iliac crest and implant placement after 3 months is a reliable technique with a high success rate and less bone resorption.

Success rate of implants placed in autogenous bone blocks versus allogenic bone blocks: A systematic literature review

The aim of this study is to review and compare survival/success rate of dental implants inserted in autogenous and allogenic bone blocks (ALBs). A PubMed search was performed from January 1990 to June 2014 limited to English language and human studies. Studies that reported treatment outcome of implants inserted in augmented alveolar ridges with autogenous or ALBs were included. Primary search identified 470 studies. For autogenous bone block (ABB) 36 articles and for ALB 23 articles met the inclusion criteria. Evidence on implant survival/success rate of both techniques was limited to observational studies with relatively small sample sizes. Study design, treatment methods, follow-ups, defect location, and morphology varied among studies. The range of implant survival and success rates in ABB was from 73.8% to 100% and 72.8% to 100%, respectively. The corresponding numbers for ALB were 95.3-100% and 93.7-100%, respectively. A definite conclusion could not be reached. Future studies with long-term follow-ups are required to further elucidate this issue.

Odontogenic myxoma of the maxilla: surgical management and case report

BACKGROUND

Odontogenic myxoma is a benign odontogenic tumour of the jaw [1]. This tumour often presents as an asymptomatic expansile lesion without sensory nerve changes [2]. It is thought to arise from mesenchymal origin with cells of microscopic similarity to dental pulp and follicle [3]. Radiographically it presents most often as a multiloculated radiolucency [2]. It is a locally aggressive lesion which may require extensive treatment to prevent recurrence.

METHOD

The authors present the case of a 13-year-old boy with an extensive lesion in the maxilla.

CONCLUSION

We discuss various treatment approaches for management of this tumour.

Measurement of the zygomatic bone and pilot hole technique for safer insertion of zygomaticus implants

The zygomaticus implant was developed for patients with severe bone resorption of the posterior maxilla. These may eliminate or minimize the need for bone grafting. Although the zygomaticus implant has shown a remarkable success rate in this difficult-to-treat patient population, the method requires an advanced surgical technique and carries an increased risk of complications. There have been few anatomical studies on the zygomatic bone in relation to the insertion of zygomaticus implants. The height and thickness of the zygomatic bone for the insertion were measured in this study. The thickness at the 90° angle point, where the upper margin of the zygomatic arch and the temporal margin of the frontal process of the zygomatic bone intersect and where the apex of the implant penetrates, was found to be 1.8±0.4 mm; this gradually increased inferiorly and anteriorly. Thus, the penetration point of the apex of the zygomaticus implant should be located more inferoanterior to the 90° angle point, as the thickness in this region is thinner than the diameter of the implant. Based on the results of this study, a newer and safer insertion method for the zygomaticus implant using a drill guide is proposed.

Calvarial Autogenous Bone Graft for Maxillary Ridge and Sinus Reconstruction for Rehabilitation With Dental Implants

Autogenous bone grafting is the gold-standard technique for bone augmentation procedures prior to implant placement. If the amount of available intraoral donor bone is insufficient, it is necessary to harvest bone graft from extraoral sites, such as calvaria. Although this technique is well established, only a few case reports show the histological analysis of the grafted bone at the moment of implant placement. This article reports the case of a 48-year-old female patient with a critical atrophic maxillary ridge reconstructed using autogenous calvarial bone graft prior to implant placement, with clinical and histological evaluation. Bone was collected under general anesthesia from the parietal bone. The outer cortical originated the bone blocks, and the medullar bone layer between was collected to be used in the sinus augmentation procedure, together with 5 of the bone blocks triturated. Six months after bone augmentation, 8 implants were placed in the grafted area and 2 biopsies were retrieved (anterior and the posterior regions), allowing the visualization of the bone-remodeling process in the grafted areas. The patient had a stable recovery. Our results showed that although necrotic bone could still be seen in the outer layer of the grafted area, the interface between this necrotic bone and the already remodeled bone was consistent with biocompatibility. Two-year radiographic evaluation showed success of the grafts and the implants in supporting an esthetic and functionally stable prosthesis. Summarizing, calvarial bone grafts are a viable alternative for the attainment of adequate bone volume prior to implant placement.

Prosthetic improvement of pronounced buccally positioned zygomatic implants: a clinical report

This report presents a prosthetic technique for the improvement of surgically positioned, buccally placed zygomatic implants with the use of custom abutments for improved retention screw position and an esthetic implant reconstruction. The patient presented four zygomatic implants with pronounced buccal inclination. The anterior implants were inclined toward the location where the anterior artificial teeth should be placed during rehabilitation. As the manufacturer does not provide angulated abutments, we attempted the waxing and overcasting of a prosthetic abutment, repositioning the access holes of the prosthetic screws to a more palatal position. This clinical report demonstrates that abutment customization could be an interesting way to relocate the access holes of the prosthetic screws in cases of zygomatic implants with pronounced buccal inclination.

Rehabilitation of a patient with gunshot injury through the iliac graft and implant-retained restorations with a 3-year follow-up: a brief clinical study

Trauma is one of the most common causes of teeth loss. Assault with a gunshot and bullet shot is life threatening, and for patients who survive the injury, it results in hard and soft tissue loss in the tissues and organs crossed by the bullet. The tissue loss results in the loss of structure and function. Rehabilitation of these patients to function and aesthetics requires surgical and prosthodontic procedures over time. This report is of a 24-year-old male patient who had a bullet injury resulting in hard and soft tissue deficiency. The ridge deficiency was augmented with iliac bone graft, and 3 months later, implants were placed. Five months later, hybrid prosthesis was delivered. At 3-year follow-up visit, the hybrid prosthesis was replaced with porcelain fused to a metal bridge. The bone levels on all the implants were stable.

Vector-controlled alveolar distraction osteogenesis using an implant-fixed provisional prosthesis: a case report

This is a case report of anterosuperior alveolar distraction using an implant-fixed provisional prosthesis. Osteotomy and placement of a distraction device were performed in a healthy 69-year-old woman. To avoid lingual inclination during the distraction period, the device's rod was buried in the labial side of a provisional prosthesis supported by posterior implants. The mandibular bone was obliquely distracted by 0.3 mm every 2 days. Implant insertion was performed, and a good prognosis was anticipated. Inclination is thought to be caused by soft tissue on the lingual side. Many reports propose methods to avoid inclination, but these methods require established support from the teeth and cannot be adapted for an edentulous case. The method reported here is useful for distraction osteogenesis because it can be adapted for edentulous cases.

Clinical recommendation for treatment planning of sinus augmentation procedures by using presurgical CAT scan images: a preliminary report

PURPOSE

To propose a clinical recommendation based on anatomy of maxillary sinus before sinus augmentation procedure using presurgical computerized axial tomography (CAT) scan images.

MATERIALS AND METHODS

CAT scan images were randomly selected from previous completed implant cases. Proposed area for the lateral window osteotomy was outlined on the panorex image of the CAT scan. Sagittal section on the CAT scan that was in the center of the outlined window was selected for sinus measurement analysis. On CAT scan, 2 lines were drawn to measure the dimensions of sinus. One line measured the horizontal width and the other line measured the vertical height.

RESULTS

Based on the measurement data, a classification of the maxillary sinus anatomy was proposed. Narrow sinus cavity indicates favorable type anatomy in terms of bone regeneration healing and wide sinus cavity as less favorable anatomy for patient treatment planning.

CONCLUSION

A narrow sinus and greater exposure to the blood supply should require shorter healing times after grafting. Conversely, wider sinus cavities and less exposure to the blood supply would require a longer healing time before implant placement.

Flabby ridge correction using an auxiliary technique with connective tissue graft

A common finding in patients with edentulous maxilla and partially dentate mandible is mainly the presence of flabbiness in the anterior edentulous alveolar ridge that can compromise the retention and stability of a denture. Thus, this case report presents the correction of a flabby ridge, using an auxiliary technique combining surgical excision and autogenous connective tissue grafting. The technique improved the quality of the osteomucosal support of the alveolar ridge and increased the vestibule deepness, whose result increased the success rate of the new conventional total prosthesis.

Retrospective analysis of survival rates and marginal bone loss on short implants in the mandible

OBJECTIVES

Short implants have become an interesting alternative to bone augmentation in dental implantology. Design of shorter implants and longer surveillance times are a current research issue. The goal of this study was to show the survival rates of short implants below 9 mm in the partly edentulous mandibular premolar and molar regions with fixed prosthetics. Marginal vertical and 2D bone loss was evaluated additionally. Different implant designs are orientationally evaluated.

MATERIAL AND METHODS

A total of 247 dental implants with fixed prosthetics (crowns and bridges) in the premolar and molar region of the mandible were evaluated; 47 implants were 9 mm or shorter. Patient data were evaluated to acquire implant survival rates, implant diameter, gender and age. Panoramic X-rays were analysed for marginal bone loss.

RESULTS

Average surveillance time was 1327 days. Cumulative survival rate (CSR) of short implants was 98% (1 implants lost) compared to 94% in the longer implants group without significance. Thirty-five of the short implants were Astratech (0 losses) and 12 were Camlog Screw Line Promote Plus (1 loss). Early vertical and two-dimensional marginal bone loss was not significantly different in short and regular length implant group with an average of 0.6 mm and 0.7 mm(2) in short implants over the observation period.

CONCLUSIONS

Within the limitations of this study, we conclude that short implants with a length of 9 mm or less have equal survival rates compared with longer implants over the observation period of 1-3 years.

Zygomatic implant placement with flapless computer-guided surgery: a proposed clinical protocol

PURPOSE

The aim of the present report is to describe a procedure for zygomatic implant placement using image-guided implant surgery. This is an innovative technique and includes a new clinical approach to provide the direction to guide drilling.

MATERIALS AND METHODS

The ethical committee of the University of Genoa approved the study. All patients had clinical indications of severe maxillary atrophy (Class 4 Cadwood-Howell). A total of 25 implants were placed, of which 17 were in the premaxilla, 7 in the zygomatic area, and 1 in the pterygoid bone. The treatment was performed in 2 phases. The first phase included cone-beam acquisition to exclude sinus disease and evaluate the anatomy of the residual premaxillary bone in 3 dimensions. The success of osseointegration achieved by the primary implants (PIs) was confirmed after temporary loading and before proceeding with the second phase, in which all patients were scheduled for zygomatic implants. A total of 3 or 4 regular platform MK III implants (17 in all) were placed in the premaxilla using conventional implant surgery. A model within the analogs of the PIs was prepared (master model), taking a conventional impression. Next, a radiologic template was prepared on the same master model and stabilized on the PIs, using dedicated prosthetic components. The guide was screwed onto the PIs during computed tomography acquisition to determine a fixed and repeatable position of the guide. In the second phase, after routine planning, a mucosa-supported stereolithographic SurgiGuide with sleeves for the zygomatic implants and the corresponding stereolithographic model, including the mucosa, were received from the manufacturers. The guide was repositioned on the master model to replace the sleeves for the PIs in the same position. With an original customized surgical kit, including an innovative intrasinus device, we next simulated surgery on the stereolithographic model to determine and control the direction of the osteotomies and the final depth of drilling. The SurgiGuide was anchored onto the PIs before the zygomatic osteotomy, after which flapless surgery was performed to place the zygomatic implants according to the plan.

RESULTS

Two PIs in the premaxillary area failed (and were replaced before the zygomatic step). No zygomatic implants failed. The follow-up examinations at 4 to 39 months showed good esthetic, phonetic, and functional results.

CONCLUSIONS

The results of the proposed surgical procedure appear to be encouraging. Although it is difficult to achieve the correct driven angle of osteotomies for zygomatic implants, in all patients we achieved correct zygomatic positioning, in agreement with previous planning. Additional research and randomized clinical trials are needed to assess the predictability of the procedure.

Analysis of osteoblastic gene expression in the early human mesenchymal cell response to a chemically modified implant surface: an in vitro study

OBJECTIVES

The effect of a chemical modification of the SLA surface (SLActive surface) on human bone marrow-derived mesenchymal cells (hMSCs) on; (1) adhesion, (2) proliferation and (3) early transcriptional control of osteogenic differentiation was investigated. We are based on the hypothesis that expression patterns of genes responsible for osteogenesis might be dependent on the characteristics of the implant surface.

MATERIAL AND METHODS

hMSCs were allowed to grow on smooth (SMO-control), SLA and SLActive implant surfaces (chemically modified). Cell attachment and proliferation were assessed at 3 and 24 h using a MTT dye reduction assay. At 24 h of culture, DNA microarray analysis examined alterations in early gene expression using a human osteogenesis gene array, including 109 cDNAs in quadruplicates of major regulatory genes for osteogenesis.

RESULTS

Initial attachment and proliferation were found to be significantly reduced. Nineteen genes were significantly upregulated when hMSCs were cultured on the SLA surfaces and 27 genes were significantly upregulated when hMSCs were cultured on the SLActive surfaces. Upregulated genes control cell differentiation, signal transduction, cell cycle regulation, angiogenesis, cell adhesion and extracellular matrix and bone formation.

DISCUSSION

Chemical modification decreases further cell attachment and proliferation and upregulates early osteoblastic differentiation genes. Hence, a microenvironment is created around chemically modified implants that may enhance osseointegration.

Dental implants placed into alveolar clefts reconstructed with tongue flaps and bone grafts

OBJECTIVE

The aim of this study was to describe a case series using surgical and prosthodontic modifications of tongue flaps necessary to adapt them for use in the reconstruction of large cleft deformities refractory to customary measures using dental implants and to study their outcomes in patients with complex cleft lip and palate deformities.

STUDY DESIGN

Five patients were treated with iliac crest bone grafts and covered by anteriorly based tongue flaps divided at either 3 or 4 weeks after surgery. The patients were followed clinically and radiographically for 3-12 years after placement of their dental implants to monitor implant survival and success.

RESULTS

One of the 5 patients suffered a partial tongue flap detachment, graft dehiscence, and recurrence of an oronasal fistula, which was successfully treated by shifting the tongue flap tissue from its new location in the palate. A total of 18 dental implants were placed into bone-grafted tissue covered by the tongue flaps. There was 1 implant failure. There were no cases of periimplantitis or bone loss in the 17 surviving implants.

CONCLUSIONS

Tongue flaps are rarely used clinical entities with a very narrow range of indications. Tongue flaps are useful in the preprosthetic reconstruction of select cases with large residual oronasal fistulae with soft tissue deficits due to scarring from previously failed surgery. Tongue flaps are extremely stressful procedures for patients to endure. Patient selection is of the utmost importance.

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.

Applications of microscale technologies for regenerative dentistry

While widespread advances in tissue engineering have occurred over the past decade, many challenges remain in the context of tissue engineering and regeneration of the tooth. For example, although tooth development is the result of repeated temporal and spatial interactions between cells of ectoderm and mesoderm origin, most current tooth engineering systems cannot recreate such developmental processes. In this regard, microscale approaches that spatially pattern and support the development of different cell types in close proximity can be used to regulate the cellular microenvironment and, as such, are promising approaches for tooth development. Microscale technologies also present alternatives to conventional tissue engineering approaches in terms of scaffolds and the ability to direct stem cells. Furthermore, microscale techniques can be used to miniaturize many in vitro techniques and to facilitate high-throughput experimentation. In this review, we discuss the emerging microscale technologies for the in vitro evaluation of dental cells, dental tissue engineering, and tooth regeneration.

Retrospective study of standard-diameter implants inserted into allografts

PURPOSE

In the last decade, several investigators reported that standard-diameter implants (SDIs) achieved excellent results. However, no report is available regarding SDIs inserted into fresh-frozen bone (FFB). We conducted a retrospective study on a series of SDIs (diameter, 3.75 mm) inserted into homologous FFB to evaluate their clinical outcome.

MATERIALS AND METHODS

The SDIs inserted with FFB were analyzed. Several variables were investigated regarding patients, anatomic sites, implants, and prosthetic restoration. Implant failure and peri-implant bone resorption were considered predictors of clinical outcome. A Kaplan-Meier algorithm and Cox regression were performed to detect those variables statistically associated with clinical outcomes.

RESULTS

One hundred thirty-three SDIs were inserted in 41 patients. Implant length ranged from 10 to 15 mm. Implants were inserted to replace 6 incisors, 13 cuspids, 60 premolars, and 54 molars. The mean follow-up was 23 months. Only 1 of 133 implants was lost (ie, survival rate=99.2%), and no differences were detected among study variables. On the contrary, crestal bone resorption correlates with type of prosthetic restoration, with a better outcome for removable dentures.

CONCLUSION

The SDIs had high survival and success rates, similar to those reported in previous studies of 2-stage procedures in nongrafted bone. The SDIs inserted into FFB are reliable, although a greater marginal bone loss is to be expected if fixed prosthetic restorations are used.