Clinical, radiographic, and immunological evaluation of angulated screw-retained and cemented single-implant crowns in the esthetic region: A 1-year randomized controlled clinical trial.

BACKGROUND: Screw-retained implant crowns are considered more biologically compatible than cemented crowns due to the absence of excess cement. However, traditional screw-retained implant crowns are not viable when the access hole of the screw channel would need to be located in an esthetic area, which would compromise the esthetic outcome of the treatment. PURPOSE: To evaluate the clinical, radiographic, and immunological outcomes of angulated screw-retained and cemented single-implant crowns in the esthetic region. MATERIALS AND METHODS: The study was a single-center, open-label, randomized controlled clinical trial. Eligible patients were randomly placed in two groups: angulated screw-retained group (AG) and cemented group (CG). Implant survival rate, bleeding on probing rate (BOP%), probing depth (PD), modified plaque index (mPI), marginal bone loss (MBL), concentrations of pro-inflammatory cytokines (TNF-α, IL-6) in peri-implant crevicular fluid (PICF), mechanical complications, and pink esthetic score/white esthetic score (PES/WES) were evaluated. RESULTS: Fifty-six patients (AG: 29, CG: 27) attended the 1-year examination. The drop-out rate was 6.67%. No implant failure was found in both groups during the observation period. BOP% was significantly lower in the AG than that in the CG (mean, 21.84% ± 19.97% vs. 37.04% ± 26.28%, p = 0.018). The concentration of TNF-α in PICF was significantly higher in the AG than that in the CG (median, 13.54 vs. 4.62, p = 0.019). No significant difference of PD, mPI, MBL, IL-6, or mechanical complication rates was found between the two groups. Mean scores for PES/WES were 21.71 and 21.64 in the AG and CG, respectively. CONCLUSION: Based on the present results, both treatment options showed acceptable clinical outcomes in the short term. Angulated screw-retained crowns might benefit the peri-implant soft tissue. However, studies with long-term follow-up are needed to confirm whether the higher concentration of TNF-α will compromise the long-term outcomes of treatment.

Intra- and inter-observer agreements in detecting peri-implant bone defects between periapical radiography and cone beam computed tomography: A clinical study.

BACKGROUND/PURPOSE: Information regarding agreements between periapical radiograph (PA) and cone beam computed tomography (CBCT) in detecting peri-implant defect is still scarce. The aim of this clinical study was to compare agreements between PA and CBCT in detecting peri-implant bone defect. MATERIALS AND METHODS: This retrospective clinical study enrolled 32 patients with both PA and CBCT filmed right after implant placement. Four modalities were used for film reading: PA1 (original), PA2 (enhanced brightness/contrast), CBCT1 (selected axial and mesial-distal direction images) and CBCT2 (all data with software). 2 experienced and 2 inexperienced observers scored all films. Intra- and inter-observer agreements were estimated with Cohen's kappa coefficient. Categorized agreements were compared and differences among four modalities were calculated. RESULTS: Agreements of PA were better than CBCT when detecting peri-implant bone defects in inter-observer agreements (median kappa 0.471 vs. 0.192; p = 0.016). Moreover, agreements in experienced observers were better than inexperienced observers (median kappa 0.883 vs. 0.567; p < 0.001). There was significant difference among four modalities except for experienced observer 2 (p = 0.218). CONCLUSION: Agreements of PA are better than CBCT when detecting peri-implant bone defects, especially for inter-observer agreements. Experienced observers are more consistent in assessment than inexperienced ones.

Circ_0008542 in osteoblast exosomes promotes osteoclast-induced bone resorption through m6A methylation.

With an increasing aging society, China is the world's fastest growing markets for oral implants. Compared with traditional oral implants, immediate implants cause marginal bone resorption and increase the failure rate of osseointegration, but the mechanism is still unknown. Therefore, it is important to further study mechanisms of tension stimulus on osteoblasts and osteoclasts at the early stage of osseointegration to promote rapid osseointegration around oral implants. The results showed that exosomes containing circ_0008542 from MC3T3-E1 cells with prolonged tensile stimulation promoted osteoclast differentiation and bone resorption. Circ_0008542 upregulated Tnfrsf11a (RANK) gene expression by acting as a miR-185-5p sponge. Meanwhile, the circ_0008542 1916-1992 bp segment exhibited increased m6A methylation levels. Inhibiting the RNA methyltransferase METTL3 or overexpressing the RNA demethylase ALKBH5 reversed osteoclast differentiation and bone resorption induced by circ_0008542. Injection of circ_0008542 + ALKBH5 into the tail vein of mice reversed the same effects in vivo. Site-directed mutagenesis study demonstrated that 1956 bp on circ_0008542 is the m6A functional site with the abovementioned biological functions. In conclusion, the RNA methylase METTL3 acts on the m6A functional site of 1956 bp in circ_0008542, promoting competitive binding of miRNA-185-5p by circ_0008542, and leading to an increase in the target gene RANK and the initiation of osteoclast bone absorption. In contrast, the RNA demethylase ALKBH5 inhibits the binding of circ_0008542 with miRNA-185-5p to correct the bone resorption process. The potential value of this study provides methods to enhance the resistance of immediate implants through use of exosomes releasing ALKBH5.

Improved response of human gingival fibroblasts to titanium coated with micro-/nano-structured tantalum.

OBJECTIVES: This study aims to evaluate the ability of tantalum-coated titanium to improve human gingival fibroblasts' adhesion, viability, proliferation, migration performance, and the potential molecular mechanisms. MATERIALS AND METHODS: Titanium plates were divided into two groups: (1) no coating (Ti, control), (2) Tantalum-coated titanium (Ta-coated Ti). All samples were characterized by scanning electronic microscopy, surface roughness, and hydrophilicity. Fibroblasts' performance were analyzed by attached cell number at 1 h, 4 h, and 24 h, morphology at 1 h and 4 h, viability at 1 day, 3 days, 5 days, and 7 days, recovery after wounding at 6 h, 12 h, and 24 h. RT-PCR, western blot were applied to detect attachment-related genes' expression and protein synthesis at 4 h and 24 h. Student's t test was used for statistical analysis. RESULTS: Tantalum-coated titanium demonstrates a layer of homogeneously distributed nano-grains with mean diameter of 25.98 (± 14.75) nm. It was found that after tantalum deposition, human gingival fibroblasts (HGFs) adhesion, viability, proliferation, and migration were promoted in comparison to the control group. An upregulated level of Integrin ß1 and FAK signaling was also detected, which might be the underlying mechanism. CONCLUSION: In the present study, adhesion, viability, proliferation, migration of human gingival fibroblasts are promoted on tantalum-coated titanium, upregulated integrin ß1 and FAK might contribute to its superior performance, indicating tantalum coating can be applied in transmucosal part of dental implant. CLINICAL SIGNIFICANCE: Tantalum deposition on titanium surfaces can promote human gingival fibroblast adhesion, accordingly forming a well-organized soft tissue sealing and may contribute to a successful osseointegration.

Bovine-Derived Xenografts Immobilized With Cryopreserved Stem Cells From Human Adipose and Dental Pulp Tissues Promote Bone Regeneration: A Radiographic and Histological Study.

Adipose tissue-derived stem cells (ADSCs) and dental pulp stem cells (DPSCs) have become promising sources for bone tissue engineering. Our study aimed at evaluating bone regeneration potential of cryopreserved ADSCs and DPSCs combined with bovine-derived xenografts with 10% porcine collagen. In vitro studies revealed that although DPSCs had higher proliferative abilities, ADSCs exhibited greater mineral depositions and higher osteogenic-related gene expression, indicating better osteogenic differentiation potential of ADSCs. After applying cryopreserved ADSCs and DPSCs in a critical-sized calvarial defect model, both cryopreserved mesenchymal stem cells significantly improved bone volume density and new bone area at 2, 4, and 8 weeks. Furthermore, the combined treatment with ADSCs and xenografts was more efficient in enhancing bone repair processes compared to combined treatment with DPCSs at all-time points. We also evaluated the sequential early bone healing process both histologically and radiographically, confirming a high agreement between these two methods. Based on these results, we propose grafting of the tissue-engineered construct seeded with cryopreserved ADSCs as a useful strategy in accelerating bone healing processes.

Long-term outcomes of osteotome sinus floor elevation without grafting in severely atrophic maxilla: A 10-year prospective study.

OBJECTIVE: The aim of the present study was to report 10-year results of osteotome sinus floor elevation (OSFE) without grafting severely atrophic maxilla (residual bone height ≤4 mm). MATERIALS AND METHODS: Patients undergoing OSFE without grafting and implant placement were included for 10-year examinations. Implant survival, complication-free survival, modified bleeding index (mBI), modified plaque index (mPI), pocket probing depth (PPD), peri-implant marginal bone loss (MBL), endo-sinus bone gain (ESBG) and mean cost of recurrence were evaluated. RESULTS: Overall, 23 patients with 35 implants attended 10-year examination. Cemented implant crowns or implant-supported fixed dental prostheses were delivered to the patients. Kaplan-Meier implant survival was 89.2% at implant level and 84.1% at patient level. Complication-free survival was 26.0% at patient level and 37.0% at implant level. The average complication-free survival time was 74.6 months (95% CI: 63.2-86.0 months) at implant level and 69.1 months (95% CI: 54.8-83.4 months) at patient level. The mBI, mPI, PPD, MBL and ESBG at 10-year follow-up were 0.91 ± 0.58, 0.48 ± 0.51, 2.94 ± 0.79 mm, 1.63 ± 0.83 mm and 2.72 ± 0.51 mm, respectively. The cost of managing recurrence was 43.6% of the initial cost of treatment. CONCLUSION: The results of the present study indicate that OSFE without grafting is a reliable treatment option in severely atrophic maxilla. Acceptable survival rate, stable MBL and ESBG could be achieved within 10 years. Low complication-free survival and high costs of recurrence management need to be considered.

Angulated screw-retained and cemented implant crowns following flapless immediate implant placement in the aesthetic region: A 1-year prospective cohort study.

PURPOSE: To compare the short-term clinical and radiographic outcomes of angulated screw-retained and cemented implant crowns following flapless immediate implant placement. MATERIALS AND METHODS: The study was designed as a prospective cohort study with 1-year follow-up. Eligible patients were divided into two groups according to restoration type: the angulated screw group (AG) and the cemented group (CG). Implant survival, marginal bone loss, mechanical complications, probing depth, bleeding on probing% and pink aesthetic score were evaluated. RESULTS: After 1 year of loading, the implant survival rate was 100% in both groups (AG, n = 23; CG, n = 20). A significantly lower bleeding on probing% was found in the AG than in the CG (11.6 ± 19.1% vs. 33.3 ± 33.8%, P = 0.04). No significant differences in marginal bone loss, probing depth and mechanical complication rates were found between the two groups (P = 0.53, 0.48, 0.41, respectively). The overall pink aesthetic score value was 8.96 ± 0.88 in the AG and 8.98 ± 0.62 in the CG at 1-year examination (P = 0.96). The percentage of excellent pink aesthetic scores (≥ 9) value increased from 48% at baseline to 83% at 1 year in the AG, and from 45% at baseline to 85% at 1 year in the CG. CONCLUSION: Based on the 1-year results, both treatment options provide high implant survival, a stable marginal bone level and excellent aesthetic outcomes in the short term. Angulated screw-retained crowns might benefit the long-term peri-implant conditions.

The responses of human gingival fibroblasts to magnesium-doped titanium.

The titanium (Ti) implant is widely used in implant dentistry; yet peri-implantitis has always been one of the most common and serious complications. Here, we demonstrated that magnesium-doping would be an effective way of enhancing the integration between implant surfaces and gingival tissues, which is critical to peri-implant health. The magnesium (2.76-6.35 at %) was immobilized onto the titanium substrate by a magnesium plasma immersion ion implantation (Mg-PIII) technique. Mg-PIII treatments did not alter surface topographies of the original titanium substrate but improved its hydrophilicity. The in vitro study including cell viability, adhesion, proliferation, migration, and real-time polymerase chain reaction assays disclosed improved adhesion, proliferation, migration, and extracellular matrix remodeling abilities of human gingival fibroblasts (HGFs) on the magnesium-doped titanium. The results of western blot suggested that the Mg-modified titanium induced the phosphorylation of AKT through the activation of PI3K. Our results revealed that magnesium-doping would potentially enhance soft tissue sealings by promoting cellular functions of HGFs in a dose-dependent manner, boding well for its applications on surfaces of implant necks in early peri-implant soft tissue integrations.

Ta-Coated Titanium Surface With Superior Bacteriostasis And Osseointegration.

BACKGROUND: Although tantalum (Ta)-based coatings have been proven to have good antibacterial activity, the underlying mechanism and in vivo biological performance remain unclear, which are essential for the clinical application of Ta-coated biomaterials as dental implants. PURPOSE: The main objective of this study is to investigate the antibacterial activity of Ta-modified titanium (Ti) implants against peri-implantitis-related microbes and the potential molecular mechanisms. METHODS: Fusobacterium nucleatum and Porphyromonas gingivalis were selected to evaluate the antibacterial activity and potential antibacterial mechanism of Ta modification. The in vivo biocompatibility of Ta-modified implants was also evaluated. RESULTS: The results showed that Ta-modified surface performed excellent antimicrobial activity against Fusobacterium nucleatum and Porphyromonas gingivalis. Micro galvanic might be formed between the incorporated Ta and the Ti base, which could consume the protons and result in decreased ATP synthesis and increased ROS generation. The gene expression of bacterial virulence factors associated with cellular attachment, invasion and viability as the target of ROS was downregulated. Importantly, in vivo biological studies showed that Ta modification significantly promoted the osseointegration of implants by stimulating the expression of bone-forming proteins. CONCLUSION: This study may provide some insights into clinical applications of Ta-coated Ti implants, especially in possibly infected situations.

[Effect of photodynamic therapy on interleukin in gingival crevicular fluid from patients receiving oral implantation].

PURPOSE: Photodynamic therapy (PDT) has been applied in treatment of peri-implantitis for its antimicrobial effects. The aim of the study was to evaluate the effects of a Denfotex PAD Light System's photodynamic therapy on prevention of peri-implantitis. METHODS: Twenty patients with implants in molar area were treated with photoactivated disinfection right after completion of suprastructures. The irradiation time was 30 seconds for mesial, distal, buccal and lingual/palatal sites respectively at a power output of 100mW. Gingival crevicular fluid (GCF) samples from these patients were obtained before photodynamic treatment, 2 weeks and 3 months after treatment. GCF was collected using paper points, and enzyme-linked immunosorbent assay (ELISA) was performed to determine the cytokine (IL-1ß, ΤΝF-α, IL-6 and ΙL-17) levels. The data were analyzed with SPSS 23.0 software package. RESULTS: ELISA showed IL-1ß and ΤΝF-α levels of all patients were decreased 2 weeks and 3 months after treatment. Reduction of IL-1ß, ΤΝF-α, IL-6 and IL-17 from 2 weeks to 3 months and from baseline to 3 months all showed a significant difference (P＜0.05). CONCLUSIONS: Denfotex PAD light system is effective in reducing peri-implant inflammatory mediators and can work as an effective treatment to prevent peri-implantitis.

Short versus longer implants with osteotome sinus floor elevation for moderately atrophic posterior maxillae: A 1-year randomized clinical trial.

PURPOSE: To compare the clinical, radiographic outcomes and patient satisfaction of short-6-mm implants and longer implants combined with osteotome sinus floor elevation (OSFE). MATERIALS AND METHODS: Two hundred and twenty-five patients with 225 implants were included and randomly assigned into three groups (each group: 75 implants) using randomizing table method: group 6 mm (6 mm implants alone), group 8 mm + O (8 mm implants + OSFE) and group 10 mm + O (10 mm implants + OSFE). Outcomes measures were as follows: implant survival, complication, resonance frequency analysis measurement, surgical time, bleeding on probing (BOP), pocket probing depth (PPD), modified plaque index (mPI), marginal bone loss (MBL) and patient satisfaction. RESULTS: The dropout rate was 3.6% at 1 year. Implant survival rates were 96%, 100% and 100% in group 6 mm, group 8 mm + O and group 10 mm + O, respectively. In group 6 mm, the survival rates of implants with diameter of 4.1 mm were 90% (27/30), while the survival rates of implants with diameter of 4.8 mm were 100% (42/42). The surgical time (min) in group 6 mm was significantly shorter than those in group 8 mm + O and group 10 mm + O (13.6 ± 2.2, 19.4 ± 3.7 and 18.3 ± 4.3, respectively, p = 0.03). No significant differences in ISQ values, BOP, PPD, mPI and MBL were found among three groups. Significant higher value of intra-operative discomfort was found in group 6 mm (p = 0.02). CONCLUSION: All treatment options provided acceptable clinical and radiographic results up to 1 year after loading. The current 1-year results must be confirmed by longer follow-ups of at least 5 years.

A study on the prevalence of dental anxiety, pain perception, and their interrelationship in Chinese patients with oral implant surgery.

BACKGROUND: Accumulating evidence has revealed that dental anxiety (DA) is associated with pain and patient satisfaction related to dental procedures. However, relevant reports are limited and inconsistent in oral implant patients. PURPOSE: The purpose of this study was to investigate the prevalence of dental anxiety, pain perception, and analyze their interrelationship in Chinese patients with oral implant surgery. MATERIALS AND METHODS: A cross-sectional study was performed according to the strengthening the reporting of observational studies in epidemiology (STROBE) guideline. Consecutive patients who received oral implant surgeries during February-March of 2018 in Shanghai Ninth People's Hospital were recruited. The modified dental anxiety scale and visual analog scale were used to evaluate the level of the patient's DA and pain perception. Multivariate logistic regression was applied to analyze the influence of DA on pain perception of patients during oral implant surgery. RESULTS: The prevalences of moderate and high preoperative DA were 66.6% and 11.9% in Chinese patients with oral implant surgery, respectively. Seven points eight percent of patients experienced pain perception during surgery. The result of multiple logistic regression showed that there was no significant influence of moderate preoperative DA (OR = 2.0, 95%CI: 0.5-8.2) on pain perception. However, a significant influence of high preoperative DA (OR = 6.4, 95%CI: 1.3-30.8) was found on pain perception of patients with oral implant surgery. Significant influences of moderate perioperative DA (OR = 5.0, 95%CI: 1.1-22.9) and high perioperative DA (OR = 8.7, 95%CI: 1.1-69.9) were also found on pain perception of patients during oral implant surgery. CONCLUSIONS: The results of the study indicated that DA was very common in Chinese patients with oral implant surgery. DA may increase pain perception of patients during oral implant surgery.

A novel semiautomatic segmentation protocol to evaluate guided bone regeneration outcomes: A pilot randomized, controlled clinical trial.

OBJECTIVES: The aims of this study were to (a) present a novel morphological contour interpolation (MCI) algorithm based method to evaluate grafted bone alterations following guided bone regeneration (GBR), (b) compare clinical and radiological outcomes of GBR with two different collagen membranes. MATERIALS AND METHODS: The data were retrieved from an ongoing randomized controlled trial. Patients were randomly allocated into two groups: (a) control group (CG): Bio-Gide (b) test group (TG): bovine dermis-derived collagen membrane. Cone beam computed tomography examinations were performed 1 week (T0) and 6 months after surgery (T1). PES/WES at T1, grafted bone volume and density changes from T0 to T1 were recorded. RESULTS: Thirty-six patients (16/20 in test/control group, respectively) were enrolled in the present study. Excellent inter-observer reliability (ICC ≥ 0.97) was revealed for repeated measurements using this method. Significant volumetric reduction of grafted bone were found in both groups (test group: from 0.60 to 0.39 cm3 , p < 0.01; control group: from 0.54 to 0.31 cm3 , p < 0.01). Mean bone density (gray-scale values) significantly increased from 305.12 to 456.69 in CG (p < 0.01). In TG, it slightly increased from 304.75 to 393.27 (p = 0.25). The mean PES/WES values were 13.84 (6.62/7.22) and 13.90 (6.70/7.20) for TG and CG, respectively. As for inter-group comparison, no significant differences of grafted bone volume change, density change and PES/WES were found between two groups. CONCLUSION: Within the limitations of this study, the novel MCI-based method is a reproducible tool to segment and visualize changes of grafted bone in 3D. Furthermore, both collagen membranes could be used as a barrier membrane for GBR in humans.

Proximal Contact Alterations Between Implant-Supported Restorations and Adjacent Natural Teeth in the Posterior Region: A 1-Year Preliminary Study.

PURPOSE: The aim of this study was to evaluate the proximal contact alterations between implant-supported restorations and adjacent natural teeth with the passage of time. In addition, potential factors influencing proximal contact loss were also evaluated. MATERIALS AND METHODS: Patients in need of implant-supported restorations in the posterior region were included. Proximal contact was divided into the following three groups: tight (group T), appropriate (group A), and open (group O). It was judged by dental floss (OralB, Essentialfloss) at restoration insertion and 1-year follow-up. In addition, patients' age, sex, implant sites, restoration type, retention type, and parafunction were recorded. RESULTS: At 1-year follow-up, 74 patients with 144 proximal contacts were included. After 1-year follow-up, the proximal contact loss rate was 24.3%, and 45.1% of proximal contacts did not show any alterations. The proximal contact loss rates in group T at baseline were significantly lower than those in group A at baseline (12.9% and 32.9%, respectively; P = .03). The proximal contact loss rates in the mandible were significantly higher than those in the maxilla (37.2% and 9.1%, respectively; P < .01). Other variables did not show a significant effect on proximal contact loss. CONCLUSION: Based on the current evidence, the proximal contact loss between implant-supported restorations and the adjacent teeth was frequent in the short term. It is helpful to reduce the proximal contact loss rate in the short term by making the proximal contact slightly tense at restoration insertion. Evaluation of proximal contact should be monitored carefully, especially in the mandible.

Endo-sinus bone formation after transalveolar sinus floor elevation without grafting with simultaneous implant placement: Histological and histomorphometric assessment in a dog model.

AIM: To evaluate endo-sinus new bone formation and implant osseointegration after transalveolar sinus floor elevation (TSFE) and simultaneous implant placement without any grafting materials and to investigate the influence of implant surface modification on bone healing process under this circumstance. MATERIALS AND METHODS: Transalveolar sinus floor elevation and simultaneous implant placement were conducted bilaterally on 12 Labrador dogs. No grafting materials were used during surgery. Implants with two different surfaces (SLA and SLActive) were placed in a split-mouth design. The animals were sacrificed 4, 8 and 24 weeks after surgery for histological and histomorphometric assessments. Bone-to-implant contact (BIC%), alveolar bone height (ABH) and the percentages of mineralized bone (MB%) in the area of interest were analysed. The probing depth (PD) and bleeding on probing (BOP) were also assessed to describe peri-implant health conditions. RESULTS: Sprouts of new bone in direct contact with implant surface were seen in the elevated area at every time point. Newly formed woven bone under sinus membrane was visible. SLActive implants exhibited favourable results compared with SLA implants regarding ABH at 4 weeks and BIC% at 4 and 8 weeks. Sites with BOP positive could be observed in both groups at any time point. No newly formed bone can be found on the implant apex with either SLA or SLActive surfaces at any time point. CONCLUSIONS: Spontaneous new bone formation from the parent bone walls could be observed after TFE without any grafting materials. No clear evidence of bone formation from the Schneiderian membrane could be found. Even though there were trends for quicker bone response of SLActive implants, this study failed to show the absolute advantage of SLActive in achieving endo-sinus bone formation.

The effect of photodynamic therapy on pathogenic bacteria around peri-implant sulcus and in the cavity between abutment and implant after healing phase: A prospective clinical study.

OBJECTIVES: To compare levels of pathogens from peri-implant sulcus versus abutment screw cavities after photodynamic therapy. MATERIAL AND METHODS: Twenty patients were included. Photodynamic therapy (PDT) was applied both in sulcus and cavities after sampling following suprastructures loading, and repeated after 2 weeks. Two samples each containing four paper points were collected for each implant at baseline, 2 weeks, 3 months: (i) peri-implant sulcus and (ii) abutment screw cavities. Seventy-five percent ethanol was applied in another 20 patients as the control group in the same way. qPCR was used to quantify periodontal pathogens: Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus mutans. RESULTS: PDT showed a better bacterial reduction than ethanol. P. g. and F. n. were most frequently detected, while less for S. m. P. gingivalis' proportion from both sites was significantly higher than the other two bacteria (P < 0.05), except for 2 weeks' peri-implant sulcus sample. Bacteria counts from abutment screw cavities were always less than those from peri-implant sulcus and was significantly lower for total bacteria at 3 months (P < 0.05). Total bacterial from abutment screw cavities significantly reduced at 3 months compared to baseline (P < 0.05). CONCLUSIONS: PDT appears to be effective in bacterial reduction compared to ethanol and can reduce P. gingivalis with short time intervals, as well as decreasing total bacteria counts within abutment screw cavities in the long run, suggesting PDT an effective way sterilizing inner surface of oral implant suprastrutures. Lasers Surg. Med. 50:433-439, 2018. © 2018 Wiley Periodicals, Inc.

Long-term outcomes of narrow diameter implants in posterior jaws: A retrospective study with at least 8-year follow-up.

OBJECTIVE: The aim of this study was to evaluate the long-term survival, complications, peri-implant conditions, marginal bone loss, and patient satisfaction of fixed dental prostheses supported by narrow diameter implants (NDIs) in the posterior jaws. MATERIALS AND METHODS: This study was designed as a retrospective cohort study with a mean follow-up time of 10.1 years (SD: 2.5 years). Patients receiving NDIs in posterior jaw were reviewed. Implant survival, hardware complication, modified plaque index (mPI), peri-implant probing depth (PPD), percentage of bleeding on probing (BOP%), marginal bone loss (MBL), and patient satisfaction were evaluated. Log-rank test and t test were used to detect the influence of implant location and restoration type. RESULTS: Sixty-seven patients with 98 NDIs (Premolar site: 81, Molar site: 17, Single crowns: 33, Splinted restorations: 65) were included. The overall implant survival rates were 96.9% at implant level and 97.0% at patient level. Veneer chipping was the most common hardware complication. The veneer chipping rates were 19.4% at patient level and 18.4% at implant level. All patients showed acceptable oral hygiene. Thus, the average MBL was 1.19 mm at implant level and 1.15 mm at patient level. Eight implants (8.5%) and six patients (9.2%) were diagnosed with peri-implantitis. Fifty-eight patients (89.2%) were satisfied with the esthetics of the restorations, while 55 patients (84.6%) were satisfied with the function of the restorations. CONCLUSION: Narrow diameter implants could be a predictable treatment option in the long term. High survival rates, high patient satisfaction, acceptable complication rates and marginal bone loss could be achieved. Further long-term studies are needed to evaluate the predictability of NDIs in molar sites.

Clinical Investigation and Patient Satisfaction of Short Implants Versus Longer Implants with Osteotome Sinus Floor Elevation in Atrophic Posterior Maxillae: A Pilot Randomized Trial.

PURPOSE: The aim of the study was to evaluate the clinical parameters and patient satisfaction of the treatments with short implants compared to longer implants with osteotome sinus floor elevation (OSFE) in atrophic posterior maxillae. MATERIALS AND METHOD: The patient data were retrieved from an ongoing randomized controlled trial (NCT02350075). Patients were randomly allocated into three groups: (group1: short-6 mm implant, group 2: short-8-mm implant with OSFE, group 3: standard-10 mm implant with OSFE). Early implant failure, complications, implant stability quotient (ISQ) and patient satisfaction by means of visual analogue scale (VAS) were evaluated. ANOVA analysis was performed for the data comparison. RESULTS: Fifty-six patients were enrolled in the present study. No implant loss was found by the end of the restoration placement. No significant difference of ISQ values was found among three groups at the time of implant surgery and impression taking (p = .67 and.54, respectively). VAS values regarding intraoperative vibratory sense in group 1 were significantly higher than those in group 3 (p = .01). CONCLUSION: All three treatments were safe in atrophic posterior maxilla (6 mm ≤ residual bone height < 8 mm). Patients were satisfied with all three treatments, while the malleting during the osteotome procedure could make patients feel uncomfortable.

Survival of Implants Using the Osteotome Technique With or Without Grafting in the Posterior Maxilla: A Systematic Review.

PURPOSE: The aim of this review was to systematically appraise survival rates of implants placed using the osteotome technique with and without grafting in the published literature. MATERIALS AND METHODS: An electronic search was conducted to identify prospective and retrospective studies on osteotome sinus floor elevation published between January 1, 2000 and October 30, 2015. Studies were included that (1) involved use of the osteotome technique with or without grafting; (2) provided data regarding the implant survival rates, residual bone height (RBH), and grafting materials; and (3) reported mean follow-up of at least 1 year after functional loading and included a minimum of 10 patients. The mean weighted cumulative implant survival rates were used to compare the two treatment strategies-grafted or nongrafted. The influence of RBH and implant length on weighted cumulative implant survival was also evaluated. RESULTS: After search and evaluation of the literature according to the inclusion criteria, 34 studies involving 1,977 patients and 3,119 implants were included. Eighty-four out of 102 implant failures documented in the studies occurred within 1 year of functional loading. Statistically significant differences in the cumulative survival rates were found in the graft and nongraft groups (95.89% and 97.30%, respectively; P = .05). In the nongraft group, no statistically significant difference in the cumulative survival rate was found when implants were placed at RBH < 5 mm or ≥ 5 mm (95.04% and 97.63%, respectively; P = .12). In the graft group, however, a statistically significant difference was found when implants were placed at RBH < 5 mm or ≥ 5 mm (92.19% and 97.59%, respectively; P < .01). Significantly lower weighted mean cumulative implant survival rates were found in the shorter (< 8 mm) implant group than in the longer (≥ 8 mm) implant group (83.33% and 96.28%, respectively; P < .01). CONCLUSION: The cumulative survival rates were significantly higher in the nongraft group than in the graft group. Early failures (< 1 year functional loading) accounted for the vast majority of the implant failures. The cumulative survival rates in the graft group were significantly lower when the RBH was < 5 mm, while the cumulative survival rates in the nongraft group demonstrated no statistically significant difference based on RBH. Shorter (< 8 mm) implants demonstrated significantly lower cumulative survival rates than longer implants.

Long-Term Outcomes of Early Loading of Straumann Implant-Supported Fixed Segmented Bridgeworks in Edentulous Maxillae: A 10-Year Prospective Study.

BACKGROUND: There have been few studies investigating the long-term outcome of early-loaded implants with segmented bridgeworks on fully edentulous maxillae. PURPOSE: To evaluate the long-term predictability of early-loaded Straumann implant-supported fixed segmented bridgeworks in edentulous maxillae. MATERIAL AND METHODS: Ninety-one implants were placed in 12 patients with edentulous maxillae. After a healing period of 6 weeks, the abutments were tightened followed by cementing of fixed full-arch prostheses. The patients were recalled after 1, 3, 5, and 10 years of loading for clinical evaluation. Implant success rate, peri-implant soft tissue condition, technical complications, marginal bone loss and patients' satisfaction was assessed. RESULTS: Eleven of the 12 patients attended the 10-year follow-up. Two implants were lost. The implant success rate was 97.6% at implant level and 81.8% at patient level. The mean marginal bone loss was found to be 0.41 ± 0.55mm, 0.53 ± 0.43mm, 0.68 ± 0.76 mm and 1.01 ± 0.85 mm at the 1, 3, 5, and 10-year follow-up respectively. None of the 11 patients showed a modified plaque index (mPLI) or modified bleeding index (mBI) of 3. Only one patient was found to have pocket probing depth (PPD) exceeding 3 mm. Peri-implantitis was found around one of the implants in a patient after 4 years of loading. The success rate of prostheses was 55.3% at prosthesis level and 27.3% at patient level. The most common technical complication of the prostheses was chipping of the ceramic veneer. Damaged veneers were observed in five patients. Other complications were loss of retention and abutment loosening. CONCLUSION: Early loading of Straumann SLA implants for support of full-arch segmented bridgeworks represents a viable therapy for the fully edentulous maxillae in the long term. High success rate of implants, acceptable peri-implant soft tissue condition and excellent patient satisfaction can be achieved, while technical complications of prostheses are common.