Maxillary Sinus Floor Elevation and Simultaneous Implant Installation via Osseodensification Drills: A Retrospective Analysis of Bone Gain in 72 Patients Followed for 6 Months.

Background/Objectives: The aim of this retrospective study was to radiographically evaluate the endo-sinus bone gain (ESBG) following osseodensification procedures using CBCT and compare the results to more conventional sinus lifting techniques. Methods: A total of 72 patients underwent crestal sinus floor elevation procedures and were provided with 102 implants with a sand-blasted and acid-etched surface with microthreads (Medentika® Microcone Implants, Hugelsheim, Germany). Patients were divided into two groups; the osseodensification group (OD; n = 36) and the osseodensified augmentation group (ODA; n = 36). Results: The mean residual bone height (RBH) was 5.71 (1.77) and 4.30 (0.94) mm in the OD and ODA groups, respectively. An ESBG of 3.45 (1.18) and 5.74 (1.31) mm was observed in the OD and ODA groups, respectively, and as compared to the baseline RBH, the ESBG was statistically significant in both groups after 6 months (p < 0.001). Conclusions: Within the limits of this retrospective study, crestal sinus lifting with the osseodensification technique seems to be a fast, effective, and safe method. Longer follow-up studies with full intrasinus bone topography and structure analyses are needed to prove the success rate of endo-sinus bone gain.

Boron- and Boric Acid-Treated Titanium Implant Surfaces in Sheep Tibia: A Histologic, Histomorphometric and Mechanical Study.

The aim of this study was to compare the topographical, chemical and osseointegration characteristics of sandblasting and acid-etching (SLA) surfaces and dental implants treated by boron compounds. Titanium (Ti) disks (n = 20) were modified using boron (B) and boric acid (H3BO3) and then compared with the conventional SLA surface via surface topographic characterizations. Dental implants (3.5 mm in diameter and 8 mm in length) with the experimental surfaces (n = 96) were inserted into the tibias of six sheep, which were left to heal for 3 and 7 weeks. Histologic, histomorphometric (bone−implant contact (BIC%)) and mechanical tests (removal torque value (RTV)) were performed. The boron-coated surface (BC group) was smoother (Rz: 4.51 µm ± 0.13) than the SLA (5.86 µm ± 0.80) and the SLA-B (5.75 µm ± 0.64) groups (p = 0.033). After 3 weeks, the highest mean RTV was found in the SLA group (37 N/cm ± 2.87), and the difference compared with the BC group (30 N/cm ± 2.60) was statistically significant (p = 0.004). After 7 weeks, the mean RTV was >80 N/cm in all groups; the highest was measured in the H3BO3-treated (BS) group (89 N/cm ± 1.53) (p < 0.0001). No statistically significant differences were found in the BIC%s during both healing periods between the groups. H3BO3 seems to be a promising medium for dental implant osseointegration.

Prevalence and predictors of bruxism in two university clinic patient populations with dental implants: A cross-sectional analysis.

OBJECTIVE: To analyze the prevalence, predictors, and prosthetic complications of bruxing patients with dental implants in two tertiary clinics in Istanbul, Turkey. METHODS: Patients with at least one dental implant and with a fixed prosthesis were examined for the evidence of probable bruxism. Factors that could be related to bruxism were analyzed in relation to patient-specific variables. Technical and mechanical complications were investigated. RESULTS: A total of 1688 patients were analyzed. The overall rate of probable bruxism was 19.72%. Besides self-reported bruxism (p < 0.022), antidepressant use (p < 0.002), frequent headaches (p < 0.014), and observation of linea alba (p < 0.028) were the predictors for probable bruxism. Technical and mechanical complications were frequent in the probable bruxers (p < 0.05). CONCLUSION: Overall prevalence of bruxism was 19.72%, and bruxism was associated with general and gender-specific predictors.

Oxytocin-loaded sustained-release hydrogel graft provides accelerated bone formation: An experimental rat study.

Restoration of the lost bone volume is one of the most deliberate issues in dentistry. Sustained-release microspherical oxytocin hormone in a poloxamer hydrogel scaffold combined with a mixture of ß-tricalcium phosphate and hydroxyapatite (CP) may serve as a suitable bone graft. The aim of this study was to design and test a novel thermosensitive hydrogel graft incorporating oxytocin-loaded poly(d, l-lactide-co-glycolide) (PLGA) sustained-release microspheres and CP. Thermosensitive poloxamer hydrogel containing CP (HCP graft) was prepared as a base and combined with hollow microspheres (HCPM) and oxytocin-loaded microspheres (HCPOM). Eighty Wistar rats were used for testing the grafts and a control group in 8-mm-diameter critical-sized calvarial defects (CSD); (n = 20). Bone healing at the 4th and 8th weeks was evaluated by histological, histomorphometric, and radiological (micro-computed tomography [µCT]) analyses. The results were analyzed by two-way analysis of variance (P < .05). Oxytocin-loaded PLGA microspheres prepared by the solvent displacement method yielded a high encapsulation efficiency of 89.5% and a slow drug release. Incorporation of the microspheres into the hydrogel graft slowed the release rate down and the release completed within 32 days. HCPOM revealed the highest new bone formation (26.45% ± 6.65% and 30.76% ± 4.37% at the 4th and 8th weeks, respectively; P < .0001) while HCPM and HCP groups revealed a bone formation of around 10% (P > .05). µCT findings of HCPOM group showed the highest mean bone mineral density values (42.21 ± 5.14 and 46.94 ± 3.30 g/cm3 for the 4th and 8th weeks, respectively; P < .0027). The proposed oxytocin-loaded sustained-release PLGA microspheres containing thermosensitive hydrogel graft (HCPOM) provide an accelerated bone regeneration in the rat calvaria.

Accuracy of dental implant placement via dynamic navigation or the freehand method: A split-mouth randomized controlled clinical trial.

OBJECTIVES: The aim of this split-mouth randomized controlled clinical trial was to compare the deviations of planned and placed implants placed by the assistance of a micron tracker-based dynamic navigation device or freehand methods. MATERIAL AND METHODS: A thermoplastic fiducial marker was adapted on the anterior teeth, and cone-beam computerized tomography was used for imaging. A minimum of one implant was planned for each side of the posterior maxilla, and the dynamic navigation device or freehand method was randomly used for surgical insertion. Deviations were measured by matching the planning data with a final CBCT image. Linear deviations (mm) between the planned and placed implants were the primary outcome. The results were analysed by generalized linear mixed models (p < .05). (NCT03471208). RESULTS: A total of 92 implants were placed to 32 volunteers, and 86 implants were included in the final analysis. For the linear deviations, mean of differences (Δ) was 0.72mm (Standard deviation (SD): 0.26); (95% Confidence interval (CI): 0.39-1.02) in the shoulder of the implants (p < .001) and 0.69mm (SD: 0.36); (95% CI: 0.19-1.19) in the tip of the implants (p < .001). For the angular deviations, Δ was 5.33° (SD: 1.63); (95% CI: 7.17-3.48); (p < .001). CONCLUSIONS: The navigation technique can be used to transfer virtual implant planning to the patient's jaw with increased accuracy.

Thermal oxidation and hydrofluoric acid treatment on the sandblasted implant surface: A histologic histomorphometric and biomechanical study.

OBJECTIVES: This study aimed to analyze and compare the topographical, chemical, and osseointegration characteristics of a sandblasted acid-etched surface (SLA group), a sandblasted thermally oxidized surface (SO group), and a surface chemically modified by hydrofluoric (HF) acid (SOF group). MATERIALS AND METHODS: Following the preparation and characterization of the relevant surfaces, 90 implants (30 for each group) were placed on the pelvic bone of six sheep. Resonance frequency analysis (RFA), insertion (ITV), removal torque value (RTV), and histomorphometric analyses (BIC%) were performed after three and 8 weeks of healing. The results were analyzed by nonparametric tests (p < 0.05). RESULTS: The roughness value (Ra) in the SOF group was significantly lower than the SLA and the SO group (p = 0.136, p < 0.001, respectively). This resulted in a substantially inferior ITV 14.83 N/cm (SD: 4.04) than those achieved in the SLA and SO groups (19.50 (SD: 6.07) and 20.17 N/cm (SD: 8.95), respectively; p = 0.001). A statistically significant change in the RFA from the baseline (47.36 ISQ, SD: 6.93) to the 3rd week (62.56 ISQ, SD: 5.29) was observed in the SOF group only (p = 0.008). The highest postplacement RFA and RTV values were measured from the SLA group (61.11 ISQ, SD: 7.51 and 78.22 N/cm, SD: 28.73). The early-term (3rd week) BIC% was highest in the SO group (39.93%, SD: 16.14). After 8 weeks, the differences in BIC% values were statistically not significant. CONCLUSIONS: Adjunct HF acid application on the thermally oxidized surface did not provide an additional benefit compared to the sandblasted and acid-etched surface (SLA group).

Combined effect of parathyroid hormone and strontium ranelate on bone healing in ovariectomized rats.

OBJECTIVE: Parathyroid hormone (PTH) enhances bone healing. Strontium ranelate (SR) is an antiresorptive agent that increases bone formation. Reports about combined effects of PTH and SR on local bone regeneration in osteoporotic subjects are limited. We aimed at investigating the efficacy of PTH and SR for promoting new bone formation in critical-sized defects of ovariectomized rats. MATERIALS AND METHODS: Parathyroid hormone- and/or SR-containing poloxamer implant tablets with/without chitosan microparticles were delivered locally to calvarial defects of 90 Wistar rats. Biopsies were analyzed histologically and histomorphometrically at 4 and 8 weeks of healing. RESULTS: Histomorphometry revealed that PTH alone promoted new bone formation at 4 weeks but the efficiency declined in 8 weeks. There was no positive effect of SR alone on bone formation at 4 or 8 weeks. Calvarial defects treated with PTH+SR combinations showed statistically significant greater new bone formation than either treatment alone at both time intervals. Tissue responses were modest and supported the good biocompatibility of the biomaterials used. CONCLUSION: Parathyroid hormone and SR combinations can be effective for calvarial bone regeneration of ovariectomized rats. PTH plus SR may have potential use as bone graft material in orthopedic and dental surgery to enhance bone healing and osseointegration.

Vascular endothelial growth factor and biphasic calcium phosphate in the endosseous healing of femoral defects: An experimental rat study.

BACKGROUND/PURPOSE: The presence of adequate bone volume is a critical factor in rehabilitative dentistry. Despite the use of many promising alloplasts, success in stimulating bone formation has been limited, mostly due to poor local biological response. Growth factors have been introduced to stimulate angiogenesis and new bone formation. This histologic and histomorphometric study aimed to evaluate the effect of vascular endothelial growth factor (VEGF) and a biphasic alloplastic graft material (BA) on the healing of endosseous defects in rats. MATERIALS AND METHODS: Twenty male Wistar rats were used. Two critical-sized bone defects were created in both the right and left femurs of each rat. Each defect was randomly assigned to be treated with VEGF, BA, or VEGF + BA, or to be left empty as a control. Half of the animals were sacrificed after 1 week, and the remaining half were sacrificed after 2 weeks. Inflammation, necrosis, and new bone areas were evaluated by means of histologic and histomorphometric analyses. RESULTS: Compared to the control group, defects treated with VEGF alone or in combination with BA showed higher rates of bone formation (33.10-46.60%) on Day 7. Additionally, VEGF significantly reduced inflammation and necrosis (P < 0.001). However, the differences were no longer discernable on Day 14. CONCLUSION: VEGF makes a significant contribution to angiogenesis and osteogenesis in the early stages of bone defect healing, and its combination with an osteoconductive grafting material (BA) may further enhance new bone formation.

The protective effects of different treatments on rat salivary glands after radiotherapy.

This study was aimed to evaluate the efficacy of treatment modalities for minimizing salivary gland damage caused by radiotherapy. Forty rats were divided into five groups. Group 1 had no irradiation or any treatment. Group 2 underwent only 15 Gy single dose radiotherapy. N-acetylcysteine, dexamethasone, hyperbaric oxygen treatment were given, respectively to the group 3, 4 and 5 for 5 days. 15 Gy single dose radiotherapy was applied to the group 3, 4 and 5 on the second day. Pyknosis, lysis, and vacuolization were examined in ductal cells and pyknosis, lysis, vacuolization, inflammation and collective duct damage in acinar cells. Dexamethasone and hyperbaric oxygen did not prove to have a positive effect on acinar and ductal cell. N-acetylcysteine-applied group had statistically significantly lower amount of damage. We determined that the decrease of ductal and acinar cell damage in parotid glands of N-acetylcysteine-applied rats was more distinct and statistically.

Evaluation of the autogenous bone block transfer for dental implant placement: Symphysal or ramus harvesting?

BACKGROUND: The absence of sufficient bone volume is the most relevant problem in implant dentistry. Grafting from exogenous sources may provide a limited gain but exhibits poor performance in large bone defects. Autogenous bone block transfer (ABBT) from the mandibular symphysis and ramus has been used with varying rates of success. The aim of this study was to compare the efficacy of symphysal and ramus ABBT for the restoration of lost horizontal alveolar bone volume in the anterior maxilla. Implants placed in the augmented areas were also evaluated. METHODS: The maxillary alveolar bone deficits of 32 patients were treated by similar-sized autogenous bone blocks (7 × 7 × 4 mm) harvested from the symphysis or ramus area. After 4 to 5 months of healing, implants were inserted. At the end of the osseointegration period, the implants were restored by fixed prostheses. Baseline bone thickness was determined by Cone beam computed tomography and was compared to post-op and one-year post-loading bone thickness values where the implants were inserted. Any complications or consequences were noted. The success and survival of the 45 implants were evaluated. The results were analyzed using the Student t-test and Fisher's exact test (p < 0.05). RESULTS: Post-op complications were frequent in both groups. Baseline bone thickness values were similar at the beginning of the study (p = 0.71) and exhibited a significant increase after the ABBT surgery (6.29 (SD 0.86) and 6.01 (SD 0.92) mm in the symphysis and ramus groups, respectively). The amount of bone thickness gain was 4.34 mm (SD: 0.92) and 4.36 mm (SD: 1.01) in the symphysis and ramus groups, respectively. After one year, the mean surface resorption was 0.6 mm (SD: 0.78) and 0.80 mm (SD: 0.56) for the symphysis and ramus groups, respectively (p = 0.089). The success and survival rates of the implants were 94.11 and 96.42 %, respectively. No graft failures were observed. CONCLUSIONS: Both symphysal and ramus ABBT procedures were successful for the restoration of a horizontal bone defect in the anterior maxilla. Ramus harvesting may be advisable due to fewer complications. Implants placed in the grafted regions exhibited a high success and survival rate within the one-year follow-up period.

Bisphosphonate-related osteonecrosis of the jaw and dental implants.

Bisphosphonate (BP) is one of the possible riskfactors in the osteonecrosis of the jaw (ON J). Surgical interventions during or after the course of treatment by using BPs may expose the patient under this risk. Animal studies, human studies, case reports, and systematic reviews are used to show the relationship between the use of bisphosphonates and dental implants. In this review data about bisphosphonaterelated osteonecrosis of the jaw (BRON J): incidence, prevention and treatment modalities for the patients who are scheduled for dental implant treatment plan and who have been already treated by dental implants will be investigated. Various views for the relationship between dental implants and bisphosphonates will be analyzed depending on the multifactors: duration, route of uptake, dosage of the drug and patient's other medications that affect the effects of bisphosphonate. All patients treated with this drug must be informed about the risk of implant loss or possibility of osteonecrosis.

Full Mouth Oral Rehabilitation by Maxillary Implant Supported Hybrid Denture Employing a Fiber Reinforced Material Instead of Conventional PMMA.

Many people have life-long problems with their dentures, such as difficulties with speaking and eating, loose denture, and sore mouth syndrome. The evolution of dental implant supported prosthesis gives these patients normal healthy life for their functional and esthetic advantages. This case report presents the fabrication of maxillary implant supported hybrid prosthesis by using Nanofilled Composite (NFC) material in teeth construction to rehabilitate a complete denture wearer patient.

A randomized clinical trial of an adjunct diode laser application for the nonsurgical treatment of peri-implantitis.

OBJECTIVE: In this radiographic and microbiologic split-mouth clinical trial, efficacy of a diode laser as an adjunct to conventional scaling in the nonsurgical treatment of peri-implantitis was investigated. BACKGROUND DATA: Eradication of pathogenic bacteria and infected sulcular epithelium presents a significant challenge in the nonsurgical treatment of peri-implantitis. MATERIALS AND METHODS: Ten patients (mean age, 55.1 years; SD, 11.4) with 48 two piece, rough-surface implants and diagnosed with peri-implantitis were recruited (NCT02362854). In addition to conventional scaling and debridement (control group), crevicular sulci and the corresponding surfaces of 24 random implants were lased by a diode laser running at 1.0 W power at the pulsed mode (λ, 810 nm; energy density, 3 J/cm(2); time, 1 min; power density, 400 mW/cm2; energy, 1.5 J; and spot diameter, 1 mm); (laser group). Healing was assessed via periodontal indexes (baseline and after 1 and 6 months after the intervention), microbiologic specimens (baseline and after 1 month), and radiographs (baseline and after 6 months). RESULTS: Baseline mean pocket depths (4.71, SD, 0.67; and 4.38, SD 0.42 mm) and marginal bone loss (2.71, SD 0.11; and 2.88, SD 0.18 mm) were similar (p = 0.09 and p = 0.12) between the control and laser groups, respectively. After 6 months, the laser group revealed higher marginal bone loss (2.79, SD 0.48) than the control groups (2.63, SD 0.53) (p < 0.0001). However, in both groups, the microbiota of the implants was found unchanged after 1 month. CONCLUSIONS: In this clinical trial, adjunct use of diode laser did not yield any additional positive influence on the peri-implant healing compared with conventional scaling alone.

Effects of complete dentures on respiratory performance: spirometric evaluation.

OBJECTIVES: There is a lack of data regarding whether edentulous subjects should remove dentures during spirometric measurements or not. The purpose of this study is to determine influences of complete dentures on spirometric parameters in edentulous subjects. MATERIALS AND METHODS: A total of 46 complete denture wearers were included in this study. Respiratory functions of the subjects were evaluated by spirometric tests that were performed in four different oral conditions: without dentures (WOD), with dentures, lower denture only and upper denture only. Forced vital capacity (FVC), peak expiratory flow, forced expiratory volume in 1 s and forced expiratory flow between 25% and 75% were evaluated. The data were analyzed with Friedman, Wilcoxon and paired-samples t tests (α = 0.05). RESULTS: Significant differences were found between spirometric parameters in different oral conditions (p < 0.05). In all spirometric parameters, the most important significant differences were found between conditions WOD, FVC and with lower dentures (FVC), and WOD (forced expiratory volume in 1 s) and with upper dentures (forced expiratory volume in 1 s) (p < 0.001). CONCLUSION: It was observed that complete dentures may unfavourably affect spirometric values of edentulous subjects. However, current findings need to be confirmed with advanced respiratory function tests.

Implant positioning errors in freehand and computer-aided placement methods: a single-blind clinical comparative study.

PURPOSE: Simultaneous insertion of multiple implants may exhibit suboptimal positions, especially in edentulous jaws considered for a fixed restoration. The aim of this study was to compare the incidence of and confounding factors in implant positioning errors related to the use of freehand and computer-aided treatment methods. MATERIALS AND METHODS: A total of 353 implants were placed in 54 patients with at least one edentulous jaw using freehand and computer-aided methods involving 16 mucosa- and 12 bone-supported single- and multiple-type stereolithographic surgical guides. At the stage of prosthesis delivery, a blinded examiner evaluated seven positioning error criteria. Results were analyzed by chi-square test and logistic regression. RESULTS: Interproximal emergence (OR = 2.82, P < .0001), insufficient interimplant distance (OR = 1.42, P < .0001), and improper parallelism (OR = 1.24, P = .001) errors were significantly higher in implants placed by the freehand method. The highest probability of positioning error (88%) was associated with the use of the freehand method, whereas the lowest (6%) was associated with single-type, mucosa-supported guides with other significant confounding factors. CONCLUSION: Utilizing computer-aided methods may alleviate the occurrence of implant positioning errors that are frequently associated with the freehand method. The use of software planning with enhanced viewing capabilities and single-type, mucosa-supported stereolithographic surgical guides in suitable patients minimizes errors.

Computer-assisted flapless implant placement reduces the incidence of surgery-related bacteremia.

OBJECTIVE: Bacteremia--the access of bacterium to the bloodstream--may yield life-threatening complications. The aim of this study was to compare the incidence, duration, and type of bacterium leading to bacteremia with relation to conventional and computer-assisted flapless implant surgery. MATERIAL AND METHODS: A total of 377 implants were placed in 68 edentulous jaws using the conventional (conventional group) or a computer-assisted stereolithographic (SLA) template-guided surgery technique (flapless group). Bacteremia was monitored from pre- and postoperative blood samples. RESULTS: The duration of the surgical intervention was significantly shorter in the flapless group (p = 0.3510). Baseline samples were sterile. Following the 15th minute after the placement of the last implant, bacteria were present in 62 and 12 % of the patients in the conventional and flapless groups, respectively (p < 0.0001; relative risk: 3.05). The differences in the incidence of the bacteremia detected at the baseline and 15 min after the last implant placement were statistically significant in the conventional group (p = 0.0001). However, no such statistical significance was present in the flapless group. Staphylocccus epidermidis, Bifidobacterium spp., Streptococcus viridans, Corynebacterium spp., and Streptococcus sanguinis were the isolated bacterium. CONCLUSIONS: Irrespective of the utilized technique, bacteremia may occur upon the placement of four to eight implants to an edentulous jaw. The probability of bacteremia for the patients operated with the conventional technique is, however, 3.05 greater than those operated with the flapless technique. CLINICAL RELEVANCE: Flapless implant placement reduces the incidence of surgery-related bacteremia and, therefore, may be beneficial to patients at risk.

Conventional multi-slice computed tomography (CT) and cone-beam CT (CBCT) for computer-aided implant placement. Part II: reliability of mucosa-supported stereolithographic guides.

PURPOSE: Deviations of implants that were placed by conventional computed tomography (CT)- or cone beam CT (CBCT)-derived mucosa-supported stereolithographic (SLA) surgical guides were analyzed in this study. MATERIALS AND METHODS: Eleven patients were randomly scanned by a multi-slice CT (CT group) or a CBCT scanner (CBCT group). A total of 108 implants were planned on the software and placed using SLA guides. A new CT or CBCT scan was obtained and merged with the planning data to identify the deviations between the planned and placed implants. Results were analyzed by Mann-Whitney U test and multiple regressions (p < .05). RESULTS: Mean angular and linear deviations in the CT group were 3.30° (SD 0.36), and 0.75 (SD 0.32) and 0.80 mm (SD 0.35) at the implant shoulder and tip, respectively. In the CBCT group, mean angular and linear deviations were 3.47° (SD 0.37), and 0.81 (SD 0.32) and 0.87 mm (SD 0.32) at the implant shoulder and tip, respectively. No statistically significant differences were detected between the CT and CBCT groups (p = .169 and p = .551, p = .113 for angular and linear deviations, respectively). CONCLUSIONS: Implant placement via CT- or CBCT-derived mucosa-supported SLA guides yielded similar deviation values. Results should be confirmed on alternative CBCT scanners.

Conventional multi-slice computed tomography (CT) and cone-beam CT (CBCT) for computer-assisted implant placement. Part I: relationship of radiographic gray density and implant stability.

PURPOSE: The relationship of conventional multi-slice computed tomography (CT)- and cone beam CT (CBCT)-based gray density values and the primary stability parameters of implants that were placed by stereolithographic surgical guides were analyzed in this study. MATERIALS AND METHODS: Eighteen edentulous jaws were randomly scanned by a CT (CT group) or a CBCT scanner (CBCT group) and radiographic gray density was measured from the planned implants. A total of 108 implants were placed, and primary stability parameters were measured by insertion torque value (ITV) and resonance frequency analysis (RFA). Radiographic and subjective bone quality classification (BQC) was also classified. Results were analyzed by correlation tests and multiple regressions (p < .05). RESULTS: CBCT-based gray density values (765 ± 97.32 voxel value) outside the implants were significantly higher than those of CT-based values (668.4 ± 110 Hounsfield unit, p < .001). Significant relations were found among the gray density values outside the implants, ITV (adjusted r(2) = 0.6142, p = .001 and adjusted r(2) = 0.5166, p = .0021), and RFA (adjusted r(2) = 0.5642, p = .0017 and adjusted r(2) = 0.5423, p = .0031 for CT and CBCT groups, respectively). Data from radiographic and subjective BQC were also in agreement. CONCLUSIONS: Similar to the gray density values of CT, that of CBCT could also be predictive for the subjective BQC and primary implant stability. Results should be confirmed on different CBCT scanners.

Stability, marginal bone loss and survival of standard and modified sand-blasted, acid-etched implants in bilateral edentulous spaces: a prospective 15-month evaluation.

OBJECTIVES: Chemical modification of the already proven sand-blasted and acid-etched (SLA) implant had increased its surface wettability and consequent early-term osseointegration characteristics. The aim of this clinical trial was to compare the stability changes, success, survival, peri-implant parameters and marginal bone loss (MBL) of the early-loaded standard (SLA) and modified sand-blasted, acid-etched (modSLA) implants. MATERIAL AND METHODS: A total of 96 SLA and modSLA implants were placed in a bi-lateral, cross-arch position to the jaws of 22 patients. Resonance frequency analysis (RFA) was used to measure the implant stability in the surgery and following healing after 1, 3 and 6 weeks. At the stage of loading, a panoramic X-ray was obtained and RFA measurement was repeated for all implants. Implants were restored by metal-ceramic crowns and followed for 1 year to determine the success, survival rate, peri-implant parameters and MBL. Results were compared by one- and two-way ANOVA, log-rank test and generalized linear mixed models (P < 0.05). RESULTS: One modSLA implant was lost after 3 weeks following the surgery yielding to a 100 and 97.91% success rate for SLA and modSLA implants, respectively (P = 0.323). At the loading stage, modSLA implants showed significantly lower MBL (0.18 ± 0.05 mm) than SLA implants (0.22 ± 0.06 mm; P = 0.002). In the loading stage, RFA value of the modSLA implants (60.42 ± 6.82) was significantly higher than the both implant types in the surgical stage (55.46 ± 8.29 and 56.68 ± 8.19), and following 1 (56.08 ± 7.01 and 55.60 ± 9.07) and 3 weeks of healing (55.94 ± 5.95 and 55.40 ± 6.50 for SLA and modSLA implants, respectively). CONCLUSIONS: modSLA implants demonstrated a better stability and a reduced MBL at the loading stage. Both SLA and modSLA implants demonstrated a favorable success and survival at the end of 15-month follow-up.

Osseointegration and stability of a modified sand-blasted acid-etched implant: an experimental pilot study in sheep.

OBJECTIVE: The aim of this pilot study was to compare the early-term osseointegration characteristics of standard (SLA) and modified sand-blasted and acid-etched (modSLA) implants in an experimental animal model. MATERIAL AND METHODS: A total of 30 SLA and modSLA implants were placed to the tibiae of three sheep and the insertion torque value (ITV) and resonance frequency analysis (RFA) measurements were performed. RFA measurement was repeated on 3 and 6 weeks healed implants after which the animals were sacrificed for histomorphometric analysis. Bone-to-implant contact was assessed on the non-decalcified sections. Six weeks healed implants were also subjected to the reverse torque test (RTT). Results were analyzed by the Friedman test, Kruskal-Wallis test and Spearman rank correlation test. RESULTS: All implants reached to a strong primary stability with a mean 36.13 ± 2.47 and 35.47 ± 2.85 N/cm ITV. In the surgical stage, RFA values for SLA and modSLA implants were found to be 72.27 ± 3.17 and 71.6 ± 2.87, respectively. After 3 weeks of healing, mean BIC% (80.64 ± 13.89%) and RFA value (76.8 ± 1.14) of modSLA implants were significantly higher (P=0.0002) than that of SLA implants (64.39 ± 21.2 BIC% and 74.2 ± 4.76 RFA). However, no statistically significant difference between SLA and modSLA implants was recorded after 6 weeks of healing. Both implants revealed similar results in the RTT test (115.2 ± 4.14 and 117 ± 4.47 N/cm for SLA and modSLA implants, respectively). No correlation was found between RFA and BIC%. CONCLUSION: Within the limits of this pilot study, it can be concluded that modSLA implants achieve a higher bone contact and stability at earlier time points when compared with SLA implants.