Roni Kolerman

Histomorphometric Analysis of Maxillary Sinus Augmentation Using an Alloplast Bone Substitute

PURPOSE To evaluate the regenerative potential of a fully synthesized homogenous hydroxyapatite:β-tricalcium phosphate 60:40 alloplast material in sinus lift procedures. MATERIALS AND METHODS Hydroxyapatite:β-tricalcium phosphate was used for sinus floor augmentation. After 9 months, 12 biopsies were taken from 12 patients. Routine histologic processing was performed and specimens were analyzed using a light microscope and a digital camera. RESULTS Histologic evaluation showed 26.4% newly formed bone, 27.3% residual graft material, and 46.3% bone marrow. The osteoconductive index was 33.5%. CONCLUSIONS Hydroxyapatite:β-tricalcium phosphate 60:40 alloplast material was found to be biocompatible and osteoconductive in maxillary sinus augmentation procedures.

3D Printing/Additive Manufacturing Single Titanium Dental Implants: A Prospective Multicenter Study with 3 Years of Follow-Up.

This prospective 3-year follow-up clinical study evaluated the survival and success rates of 3DP/AM titanium dental implants to support single implant-supported restorations. After 3 years of loading, clinical, radiographic, and prosthetic parameters were assessed; the implant survival and the implant-crown success were evaluated. Eighty-two patients (44 males, 38 females; age range 26–67 years) were enrolled in the present study. A total of 110 3DP/AM titanium dental implants (65 maxilla, 45 mandible) were installed: 75 in healed alveolar ridges and 35 in postextraction sockets. The prosthetic restorations included 110 single crowns (SCs). After 3 years of loading, six implants failed, for an overall implant survival rate of 94.5%; among the 104 surviving implant-supported restorations, 6 showed complications and were therefore considered unsuccessful, for an implant-crown success of 94.3%. The mean distance between the implant shoulder and the first visible bone-implant contact was 0.75 mm (±0.32) and 0.89 (±0.45) after 1 and 3 years of loading, respectively. 3DP/AM titanium dental implants seem to represent a successful clinical option for the rehabilitation of single-tooth gaps in both jaws, at least until 3-year period. Further, long-term clinical studies are needed to confirm the present results.

Accuracy of a laboratory-based computer implant guiding system

OBJECTIVE Computer-guided implant placement is a growing treatment modality in partially and totally edentulous patients, though data about the accuracy of some systems for computer-guided surgery is limited. The purpose of this study was to evaluate the accuracy of a laboratory computer-guided system. STUDY DESIGN A laboratory-based computer guiding system (M Guide; MIS technologies, Shlomi, Israel) was used to place implants in a fresh sheep mandible. A second computerized tomography (CT) scan was taken after placing the implants . The drill plan figures of the planned implants were positioned using assigned software (Med3D, Heidelberg, Germany) on the second CT scan to compare the implant position with the initial planning. Values representing the implant locations of the original drill plan were compared with that of the placed implants using SPSS software. RESULTS Six measurements (3 vertical, 3 horizontal) were made on each implant to assess the deviation from the initial implant planning. A repeated-measurement analysis of variance was performed comparing the location of measurement (center, abutment, apex) and type of deviation (vertical vs. horizontal). The vertical deviation (mean -0.168) was significantly smaller than the horizontal deviation (mean 1.148). CONCLUSION The laboratory computer-based guiding system may be a viable treatment concept for placing implants.

Combined Osteotome‐Induced Ridge Expansion and Guided Bone Regeneration Simultaneous with Implant Placement: A Biometric Study

Purpose To evaluate the long-term outcome of a single-step ridge expansion osteotome procedure and implant placement combined with guided bone regeneration in patients presenting narrow maxillary alveolar ridges. Materials and Methods During the period 1999 to 2010, 41 patients aged 19 to 77 years (18 males; 23 females) suffering from partial or full edentulism associated with horizontal resorption of the maxillary ridges (2.5–5 mm) were treated using the combined ridge expansion and guided bone-regeneration techniques to obtain an improved bony base for implant placement. Implant survival, bone width measurements, clinical and radiologic implant success, and clinical complications were recorded and analyzed. Results Achievement of primary stability of the implant was impossible at six sites; these were recorded as failures. In the remaining 35 patients, one hundred sixteen endosseous titanium implants were simultaneously placed. Follow-up time varied between 6 and 144 months (mean 52.4); of these, 36% were followed up for periods of time longer than 60 months. Implant diameter and lengths varied between 3.3 to 4.8 and 12 to 16 mm, respectively. In the 35 successful procedures (one hundred sixteen implants), the overall implant survival rate was 100%. An average gain in ridge width was 3.5 ± 0.93 (p < .0001) and an average enlargement of the buccal bone was 1.91 ± 0.6 (p < .0001). The mean vertical mesial bone loss was 1.81 mm ± 1.07 (ranging from 0.3 to 4.2 mm), and the mean vertical distal bone loss was 1.74 mm ± 1.12 (ranging from 0.4 to 4.5 mm). In eight patients (32%), at least one implant presented bone loss of ≥3 mm. Conclusions Within the limitations of this study, we suggest that the combined osteotome-induced ridge expansion and guided bone regeneration simultaneous with implant placement is a reliable procedure with reduced morbidity and may offer an alternative in suitable situations.PURPOSE To evaluate the long-term outcome of a single-step ridge expansion osteotome procedure and implant placement combined with guided bone regeneration in patients presenting narrow maxillary alveolar ridges. MATERIALS AND METHODS During the period 1999 to 2010, 41 patients aged 19 to 77 years (18 males; 23 females) suffering from partial or full edentulism associated with horizontal resorption of the maxillary ridges (2.5-5 mm) were treated using the combined ridge expansion and guided bone-regeneration techniques to obtain an improved bony base for implant placement. Implant survival, bone width measurements, clinical and radiologic implant success, and clinical complications were recorded and analyzed. RESULTS Achievement of primary stability of the implant was impossible at six sites; these were recorded as failures. In the remaining 35 patients, one hundred sixteen endosseous titanium implants were simultaneously placed. Follow-up time varied between 6 and 144 months (mean 52.4); of these, 36% were followed up for periods of time longer than 60 months. Implant diameter and lengths varied between 3.3 to 4.8 and 12 to 16 mm, respectively. In the 35 successful procedures (one hundred sixteen implants), the overall implant survival rate was 100%. An average gain in ridge width was 3.5 ± 0.93 (p < .0001) and an average enlargement of the buccal bone was 1.91 ± 0.6 (p < .0001). The mean vertical mesial bone loss was 1.81 mm ± 1.07 (ranging from 0.3 to 4.2 mm), and the mean vertical distal bone loss was 1.74 mm ± 1.12 (ranging from 0.4 to 4.5 mm). In eight patients (32%), at least one implant presented bone loss of ≥3 mm. CONCLUSIONS Within the limitations of this study, we suggest that the combined osteotome-induced ridge expansion and guided bone regeneration simultaneous with implant placement is a reliable procedure with reduced morbidity and may offer an alternative in suitable situations.

Evaluation of Volumetric Changes of Augmented Maxillary Sinus With Different Bone Grafting Biomaterials.

AbstractExtensive alveolar bone resorption because of pneumatized maxillary sinus is a common problem that limits dental implant placement. Maxillary sinus floor augmentation (MSFA) is an accepted treatment protocol that provides sufficient bone volume. The aim of this study was to evaluate the percentage of graft volume reduction following MSFA using cone beam computed tomography. In this retrospective study, cone beam computed tomography scans of MSFA were measured to evaluate the volume of the grafted sinus with deproteinized bovine bone (DBB), mineralized allograft (MA), or a mixture of MA and demineralized allograft as a composite. The volumetric changes in sinus augmentation between 2 weeks (T-I) and 6 months (T-II) after operation were analyzed. Thirty-nine patients were included in this study. The average percent volume reduction was 8.14 ± 3.76%, 19.38 ± 9.22%, and 24.66 ± 4.68% for DBB, MA, and composite graft, respectively. A significant graft volume reduction was found between T-I and T-II for all groups (P < 0.01). The DBB group showed the least volume reduction (P < 0.01). Biomaterials can influence the bone graft volume change before implant placement. Deproteinized bovine bone may offer greater volume stability during healing than mineralized and composite allografts.

Radiological and Biological Assessment of Immediately Restored Anterior Maxillary Implants Combined with GBR and Free Connective Tissue Graft.

OBJECTIVES Radiologic and biologic assessment of immediately restored Implants combined with guided bone regeneration (GBR) and free connective tissue graft. METHODS 1-4 year retrospective study involving 34 patients treated with maxillary immediately restored anterior single-implants. Soft tissue dimensions, radiographic bone loss, and biological and prosthetic complications were assessed. RESULTS During the mean follow up period of 29 months the study group presented a mean mesial bone loss of 1.10 ± 0.39 mm (range: 0.5-2.4 mm), and mean distal bone loss of 1.19 ± 0.41 mm (range: 0.4-2.1 mm). Mean periimplant probing depth of 3.49 mm (SD ± 1.06) and 2.35 (SD ± 0.52) for the contralateral tooth (highly significant p < 0.001). Bleeding on probing was present in 29.4% of the examined implant supported crown sites and 10.4% of the contralateral teeth (p < 0.001). CONCLUSIONS Anterior maxillary single-tooth replacement, using GBR and connective tissue graft according to the concept of immediate implant placement, and non-functional restoration is an accepted treatment modality achieving favorable peri-implant soft tissue condition.Objectives Radiologic and biologic assessment of immediately restored Implants combined with guided bone regeneration (GBR) and free connective tissue graft. Methods 1–4 year retrospective study involving 34 patients treated with maxillary immediately restored anterior single-implants. Soft tissue dimensions, radiographic bone loss, and biological and prosthetic complications were assessed. Results During the mean follow up period of 29 months the study group presented a mean mesial bone loss of 1.10 ± 0.39 mm (range: 0.5–2.4 mm), and mean distal bone loss of 1.19 ± 0.41 mm (range: 0.4–2.1 mm). Mean periimplant probing depth of 3.49 mm (SD ± 1.06) and 2.35 (SD ± 0.52) for the contralateral tooth (highly significant p < 0.001). Bleeding on probing was present in 29.4% of the examined implant supported crown sites and 10.4% of the contralateral teeth (p < 0.001). Conclusions Anterior maxillary single-tooth replacement, using GBR and connective tissue graft according to the concept of immediate implant placement, and non-functional restoration is an accepted treatment modality achieving favorable peri-implant soft tissue condition.

The Use of Tilted Implant for Posterior Atrophic Maxilla

PURPOSE To retrospectively analyze the influence of implant inclination on marginal bone loss at freestanding implant-supported fixed partial prostheses (FPPs) over a medium-term period of functional loading. MATERIALS AND METHODS Twenty-nine partially edentulous patients with freestanding FPDs supported by two implants placed in a two-stage procedure comprised the study group. The anterior implant was placed axially, and the posterior tilted distally. Mesial or distal inclination of each implant was measured in relation to the vertical axis perpendicular to the occlusal plane. Average bone loss was compared between straight and tilted implants, smokers, and nonsmokers. RESULTS Mean angulation of the anterior axial-positioned implant was 3.45 degrees distally (range 0-8) and of the distal implants was 32.83 degrees distally (range 20-50 degrees). Average bone loss after 1, 3, and 5 years was 0.89 (SD = 0.73), 1.18 (SD = 0.74), and 1.50 (SD = 0.81), respectively, for axial implants, and 0.98 (SD = 0.69), 1.10 (SD = 0.60) and 1.50 (SD = 0.67) for tilted implants, with no significant correlation between implant angulation and bone loss. A significant correlation between implant angulation and annual bone loss was obtained for tilted implants only (r = 0.52, p = .004).Using Albrektsson criteria, the success rate was 89.6% (26 out of 29 implants) for straight and 93.1% (27 out of 29) for tilted implants. CONCLUSION The study demonstrates no effect of implant angulation on peri-implant bone loss in the posterior maxilla.

Reliability of retrievable cemented implant-supported prostheses.

STATEMENT OF PROBLEM One of the disadvantages of a cemented implant restoration is the potential difficulty of retrieving it. The restoration may be destroyed during removal. PURPOSE The purpose of this retrospective clinical study was to assess the long-term survival rates of cemented posterior metal ceramic implant-supported prostheses (ISPs) with a metal screw access hole. MATERIAL AND METHODS During a 12-year period, 274 cemented ISPs with an abutment screw access hole in the metal framework were assessed and served as the study group, and 119 conventional cemented ISPs (without access hole) served as the control group. Participants were followed every 6 months in the first year and once a year subsequently. Ceramic fracture, screw loosening, and refabrication were the prosthetic outcome parameters evaluated at the recall. The Pearson Chi square and Fisher exact test were used to compare the outcome parameters between the control and study groups. RESULTS A total of 1005 implants and 393 ISPs were evaluated. Ceramic fracture occurred in 6.6% of the ISPs (6.2% test and 7.6% control). Screw loosening occurred in 3.28% of the test group and 3.36% of the control group. Refabrication of ISPs was done in 2.79% of all restorations, (1.45% test and 6.72% control [P=.012]). CONCLUSIONS Within the limits of this study, preparing cemented ISPs with a screw access hole in the metal framework improves ISP survival rates over time and lowers the cost of maintenance without increasing the risk for porcelain fracture or screw loosening.

Comparison of Two Techniques for Lateral Ridge Augmentation in Mandible With Ramus Block Graft.

Abstract The purpose of this manuscript was to assess mandibular ramus block grafts used for augmentation of mandibular posterior segments, followed by subsequent implant placement. Twenty-four human subjects in need of lateral ridge mandibular augmentation were included in the current patient series. Inclusion criteria: recipient site had at least 10-mm residual height, but less than 4.3-mm bucco-lingual dimension. Autogenous bone blocks were harvested from the mandibular ramus. In the first group ramus block was used in association with platelet-rich fibrin and in the second in association with pericardium membrane. Implant surgery was performed 4 months after bone graft surgery when a total number of 44 implants were placed. Abutments were placed 4 months after implant surgery followed by final restoration. Ramus bone graft was successful in 100% patients for the first group and in 91.67% patients for the second group. Measurement on cone beam computed tomography revealed an average of 5.35 mm of lateral ridge augmentation for group 1 and 5.099 mm for group 2, achieved 4 months after surgery. All implants placed received fixed prosthetic restorations and are in use. Ramus block grafts can be used to allow optimal implant placement, with favor long-term success. Lateral ridge augmentation using mandibular ramus bone graft in association with platelet-rich fibrin is a more predictable and successful technique.

Comparison between mineralized cancellous bone allograft and an alloplast material for sinus augmentation: A split mouth histomorphometric study

BACKGROUND Several grafting materials have been used in sinus augmentation procedures including autogenous bone, demineralized freeze-dried bone, hydroxyapatite, β-tricalcium phosphate, anorganic deproteinized bovine bone, and combination of these and others. Yet, the issue of the optimal graft material for sinus floor augmentation is controversial. PURPOSE This prospective, randomized split-mouth study was undertaken to histomorphometrically compare a biphasic calcium phosphate (BCP) alloplastic bone substitute and a human bone mineral allograft (freeze-dried bone allograft, FDBA) in patients undergoing bilateral maxillary lateral sinus floor augmentation. MATERIAL AND METHODS Apico-coronal core biopsies were harvested at 9 months from 26 bilateral sites in 13 treated patients. Specimens were processed for histological and histomorphometrical analyses. RESULTS Newly formed bone (NB) was evident in all specimens with values of 27.5% and 24.0% at the FDBA and BCP sites, respectively (P = .331). The residual graft particle values were 12.5% and 25.4% (P = .001), and the connective tissue values were 60.0% and 50.6%, respectively. The osteoconductive value was 52.6% for the FDBA and 26.7% for the alloplast (P = .001). The values for the measured residual graft particles, connective tissue, and osteoconductivity, but not for NB, showed highly significant differences between the two groups. All sections in the alloplast material showed evidence of a light chronic inflammatory infiltrate, mainly comprising lymphocytes and multinucleated giant cells. CONCLUSIONS Both graft materials are suitable for sinus floor augmentation, with the allograft material being more osteoconductive.