The effects of using erbium, chromium-doped:yttrium-scandium-gallium-garnet laser on the surface modification, bacterial decontamination, and cell adhesion on zirconia discs: an in vitro study.

The use of zirconia for implants and abutments has become more prevalent in implant dentistry as an alternative to the commonly used titanium implants, and peri-implant disease can still affect them. The erbium, chromium-doped:yttrium-scandium-gallium-garnet (Er, Cr:YSGG) laser has emerged as a promising treatment modality. The purposes of this in vitro study were to (1) determine the effects of the laser on the surface roughness of zirconia discs; (2) determine the extent of removal of a single species biofilm, E. coli, on the zirconia discs after applying the laser; (3) determine the amount of cell adhesion and proliferation utilizing fibroblasts on zirconia discs after treatment with the laser. All treatments will be compared with the commonly used ultrasonic instrumentation and hand scalers. For the first aim, gross examination revealed noticeable surface damage on the discs when using ultrasonic and scalers but not for the laser group. For surface roughness, the mean roughness was Pa= 0.623±0.185 µm, 0.762±0.421 µm, 0.740±0.214 µm, and 0.724±0.168 µm for control discs, and discs treated with either the Er,Cr:YSGG laser, ultrasonic instrumentation, and hand scalers respectively. There was no statistical significance among the groups (p=0.628). For bacteria decontamination, there was a statistical significance among the groups (p< 0.0001). Statistical significance was seen between the control group and each of the three treatment groups, favoring the treatment groups (p< 0.0001). Statistical significance was seen when comparing ultrasonic instrumentation and hand scalers (p= 0.000) as well as when comparing the Er,Cr:YSGG laser to hand scalers (p= 0.007), favoring both the ultrasonic instrumentation and Er,Cr:YSGG laser. No significance between the Er,Cr:YSGG laser group and the ultrasonic instrumentation group was noted (p =0.374). When comparing the cell attachment following treatment in each of the three groups and also without treatment (control), there was a statistical significance among the groups (p<0.0001) in terms of total cell count, favoring the control and the laser groups. Further evaluations with SEM showed differences in cell morphology indicating more adherent cells on Er,Cr:YSGG laser-treated surfaces. In conclusion, gross examination of the discs show clear surface changes when using ultrasonic instrumentation and hand scalers compared to the Er,Cr:YSGG laser group. The Er,Cr:YSGG laser was able to effectively ablate bacteria from zirconia disc. Fibroblast attachment on the surfaces of the zirconia discs shows more adherence when treated with Er,Cr:YSGG laser.

Establishment of perpendicular protrusion of type I collagen on TiO2 nanotube surface as a priming site of peri-implant connective fibers.

Natural teeth are supported by connective tissue collagen fibers that insert perpendicularly in the tooth cementum. Perpendicular insertion plays an important role in the maintenance of the junction between the oral epithelium and the periodontal connective tissue. Most titanium dental implant surfaces have no micro or macro structure to support perpendicularly oriented collagen attachment. Without this tight biologic seal to resist bacterial invasion and epithelial downgrowth, progressive bone loss in peri-implantitis is seen around dental implants. The purpose of this study was to establish the perpendicularly oriented collagen attachment to titanium oxide nanotube (TNT), and to assess its binding stability. TNT was prepared on the titanium-surface by anodization. Scanning electron microscopy (SEM) showed a regularly aligned TNT with an average 67 nm-diameter when anodized at 30 V for 3 h. Subsequently, collagen type I (CoI) was electrophoretically fused to anodic TNT in native polyacrylamide gel system where negatively charged CoI-C term was perpendicularly navigated to TNT. SEM and atomic force microscopy (AFM) were used to analyze CoI on the TiO2 and TNT surface. Several tens of nanometers of CoI protrusion were recorded by AFM. These protrusions may be long enough to be priming sites for cell-secreted CoI. CoI laid parallel to the titanium surface when fused by a chemical linker. Binding resistance of CoI against drastic ultrasonication was measured by Fourier-transform infrared spectroscopy attenuated total reflection (FTIR-ATR). The electrophoretically fused CoI in the titanium nanotube (TNT-CoIEPF) showed the significantly greatest binding resistance than the other groups (P < 0.01, a 1-way ANOVA and Tukey HSD post hoc test). Furthermore, TNT-CoIEPF surface rejected epithelial cell stretching and epithelial sheet formation. Chemically linked horizontal CoI on titanium oxide (TiO2) facilitated epithelial cell stretching and sheet formation.

A prospective clinical trial to assess the optical efficacy of pink neck implants and pink abutments on soft tissue esthetics.

OBJECTIVE: The purpose of this prospective, randomized, controlled, multicenter clinical study was to analyze the optical effects of an anodized pink colored implant shoulder/abutment system in the peri-implant mucosa of immediately placed dental implants. MATERIALS AND METHOD: Forty subjects with a restoratively hopeless tooth in the maxillary esthetic zone, were recruited and randomized to receive either a pink-neck implant, or a conventional gray implant. All patients received an immediate implant and immediate provisional and two identical CAD/CAM titanium abutments with different surface colors: pink and gray, and one zirconia all-ceramic crown. The color of the peri-implant mucosa was measured using a dental spectrophotometer and analyzed using CIELAB color system. RESULTS: The overall color difference between the peri-implant mucosa with a pink abutment and a gray abutment was ΔE = 4.22. Patients with gray implants presented a color change of ΔE = 3.86-4.17 with this abutment change, while patients with pink implants had a color change of ΔE = 3.84-4.69. The peri-implant mucosa with a pink abutment was significantly more red when compared with a gray abutment (P ≤ .01). CONCLUSIONS: When a pink abutment was used, there is a significant color change of the peri-implant mucosa that is above the detectable color threshold. CLINICAL SIGNIFICANCE: Esthetic outcomes are important for the success of implant treatment of maxillary anterior implants. The phenomenon of the gray color of a dental implant and abutment shining through the peri-implant mucosa has been documented in the literature. The objective of this study was to assess the optical effect of an anodized pink-neck implant and a pink abutment on the color of peri-implant mucosa. This study demonstrates that using pink-neck implant and a pink abutment would contribute positively to the overall esthetic outcome for an anterior implant.

The use of endothelial progenitor cells combined with barrier membrane for the reconstruction of peri-implant osseous defects: an animal experimental study.

BACKGROUND: The aim of this research was to study the efficacy of endothelial progenitor cells (EPC) with ß tri-calcium phosphate (ß-TCP) and barrier in the treatment of experimental peri-implantitis. METHODS: Thirty implants were placed in five American foxhounds. Following osseointegration, ligature-induced peri-implantitis was initiated. EPC were isolated from peripheral blood. Two months later, open flap debridement was performed and implants' surface was decontaminated with 24% EDTA. The sites were grafted with ß-TCP and collagen membrane (ß-TCP group) or ß-TCP loaded with EPC and covered with membrane (EPC group) or left un-grafted (OFD group). At 3 months, animals were killed and specimens sent for histomorphometric and micro-CT analysis. Bone height and %BIC served as primary and secondary outcomes. RESULTS: EPC group showed shorter distance to first BIC (3.29 ± 0.69 mm) compared to 4.2 ± 0.92 mm (ß-TCP) and 3.82 ± 0.73 mm (OFD). Mean histological BIC was 2-3 folds higher in the EPC group (17.65 ± 3.3%) compared with OFD (7.55 ± 2.24%, p = 0.01) and ß-TCP (5.68 ± 2.91%, p = 0.05). BIC greater than 25% was found only in the EPC group. The distance between the implant shoulder to 1st BIC was 2.51 ± 0.7 mm (lingual sites) compared to 3.64 ± 0.8 mm for buccal sites (p < 0.0001). CONCLUSION: ß-TCP loaded with EPC and covered with a membrane-enhanced bone formation around previously contaminated dental implants in an experimental peri-implantitis canine model.

Self-reported Oral Hygiene Habits in Smokers and Nonsmokers Diagnosed with Periodontal Disease.

PURPOSE: To determine whether smokers report having less adequate oral hygiene habits than nonsmokers. MATERIALS AND METHODS: Using a 24-item questionnaire addressing both smoking and oral hygiene habits, patients from three periodontal practices in Spain were evaluated. In order to assess the periodontal status of all patients, immediately following the survey, the patients were examined clinically and categorised according to the American Dental Association (ADA) classification for periodontal diseases. RESULTS: 762 patients with ADA type I gingivitis (4.1%), type II early periodontitis (31.2%), type III moderate periodontitis (39.2%) and type IV advanced periodontitis (25.5%) were surveyed. A total of 289 smokers (38.0%) and 402 (52.8%) nonsmokers participated in the study: 77 (10.1%) participants were identified as heavy smokers (>20 cigarettes/day), along with 122 (16.0%) moderate smokers (10-20 cigarettes/day) and 90 (11.8%) light smokers (<20 cigarettes/day). A greater proportion of nonsmokers brushed their teeth two (37.8%) or more (22.9%) times a day compared with moderate smokers (twice: 32.0%, more: 15.6%) and heavy smokers (twice: 32.5%, more: 15.6%), respectively (p < 0.05). Heavy smokers used dental floss statistically significantly less frequently (10.4%) than nonsmokers (21.6%) (p < 0.05). No statistically significant differences were found between smokers and nonsmokers regarding the use of mouthwashes (p > 0.05). CONCLUSIONS: This study revealed comparable oral hygiene habits in nonsmokers and light smokers. However, heavy smokers were found to have worse oral hygiene habits than nonsmokers.

Successful nonsurgical management of post-orthodontic gingival enlargement with intensive cause-related periodontal therapy.

Successful nonsurgical management of severe postorthodontic gingival enlargement and erythema in a 24-year-old male is presented. The patient received an intensive cause-related periodontal therapy, consisting of oral hygiene instruction, scaling and root planing, and weekly recall visits. At week five, complete resolution of the lesions was achieved. By targeting the primary etiologic factor, i.e., plaque, periodontal health was restored without needing surgical intervention. Reducing the bacterial load will give the biologic natural healing capacity of the body the opportunity to stabilize the periodontal condition and, thus, should be considered as the first line of intervention before a surgical approach is taken.

Efficacy of growth factor in promoting early osseointegration.

A preclinical study was conducted to evaluate the feasibility of 2 different topical formulations of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) to promote early osseointegration and enhanced bone-to-implant contact (BIC) for dental implants placed in an edentulous ridge. Six female beagle dogs were divided into 3 groups. The control group included 4 implants with no coating; test group A included 10 implants with commercially available rhPDGF-BB formulation coating; and second test group B included 10 implants with prototype viscous rhPDGF-BB coating. Three dogs were sacrificed at 3 weeks (12 implants) and the remaining 3 dogs at 6 weeks after implant placement (12 implants). The specimens were retrieved for histological evaluation, and revealed an uneventful healing of all implants without any sign of an inflammatory response at the different time intervals. Furthermore, the bone was in very close contact with the implants' surfaces with no evidence of intervening fibrous tissue layers. At 3 weeks, new bone formation between most implant threads on rhPDGF-BB coated implants was evident, whereas in the control group only a thin and sparse amount of new bone was noted. At 6 weeks, the commercially available rhPDGF-BB formulation coated implant group (Group A) showed more trabecular bone and higher BIC compared to the other 2 groups. Histologically, the results in this study showed that use of conventionally available rhPDGF-BB formulation as the implant surface treatment may accelerate the process of osseointegration and enhance BIC.

Risk indicators for gingival recession in the esthetic zone: A cross-sectional clinical, tomographic, and ultrasonographic study.

BACKGROUND: To evaluate the risk indicators associated with midfacial gingival recessions (GR) in the natural dentition esthetic regions. METHODS: Cone-beam computed tomography (CBCT) results of thirty-seven subjects presenting with 268 eligible teeth were included in the cross-sectional study. Clinical measurements included presence/absence of midfacial GR; the depth of the midfacial, mesial, and distal gingival recession; the recession type (RT); keratinized tissue width (KT); and attached gingiva width (AG). Questionnaires were utilized to capture patient-reported esthetics and dental hypersensitivity for each study tooth. Buccal bone dehiscence (cBBD) and buccal bone thickness (cBBT) were measured on the CBCT scans. High-frequency ultrasonography was performed to assess gingival thickness (GT) and buccal bone dehiscence (uBBD). Intraoral optical scanning was obtained to quantify the buccolingual position of each study site (3D profile analysis). Multilevel logistic regression analyses with generalized estimation equations were performed to assess the factors associated with the conditions of interest. RESULTS: The presence of midfacial GR was significantly associated with the history of periodontal treatment for pocket reduction (OR 7.99, p = 0.006), KT (OR 0.62, p < 0.001), cBBD (OR 2.30, p = 0.015), GT 1.5 mm from the gingival margin (OR 0.18, p = 0.04) and 3D profile 1 mm from the gingival margin (OR 1.04, p = 0.001). The depth of midfacial GR was significantly correlated to previous history of periodontal treatment (OR 0.96, p = 0.001), KT (OR -0.18, p < 0.001), presence of bone fenestration (OR 0.24, p = 0.044), and cBBD (OR 0.43, p < 0.001). The depth of midfacial GR was also the only factor associated with patient-reported esthetics (OR -3.38, p = 0.022), while KT (OR 0.77, p = 0.018) and AG (OR 0.82, p = 0.047) were significantly correlated with patient-reported dental hypersensitivity. CONCLUSIONS: Several risk indicators of midfacial and interproximal GR in the esthetic region were identified. The use of imaging technologies allowed for detection of parameters associated with the conditions of interest, and, therefore, their incorporation in future clinical studies is advocated. Ultrasonography could be preferred over CBCT for a noninvasive assessment of periodontal phenotype.

Spatial mapping of mobile genetic elements and their bacterial hosts in complex microbiomes.

The exchange of mobile genetic elements (MGEs) facilitates the spread of functional traits including antimicrobial resistance within bacterial communities. Tools to spatially map MGEs and identify their bacterial hosts in complex microbial communities are currently lacking, limiting our understanding of this process. Here we combined single-molecule DNA fluorescence in situ hybridization (FISH) with multiplexed ribosomal RNA-FISH to enable simultaneous visualization of both MGEs and bacterial taxa. We spatially mapped bacteriophage and antimicrobial resistance (AMR) plasmids and identified their host taxa in human oral biofilms. This revealed distinct clusters of AMR plasmids and prophage, coinciding with densely packed regions of host bacteria. Our data suggest spatial heterogeneity in bacterial taxa results in heterogeneous MGE distribution within the community, with MGE clusters resulting from horizontal gene transfer hotspots or expansion of MGE-carrying strains. Our approach can help advance the study of AMR and phage ecology in biofilms.

Antiviral CD4+ memory T cells are IL-15 dependent.

Survival and intermittent proliferation of memory CD4(+) and CD8(+) T cells appear to be controlled by different homeostatic mechanisms. In particular, contact with interleukin (IL)-15 has a decisive influence on memory CD8(+) cells, but not memory CD4(+) cells. Past studies of memory CD4(+) cells have relied heavily on the use of naturally occurring memory phenotype (MP) cells as a surrogate for antigen (Ag)-specific memory cells. However, we show here that MP CD4(+) cells contain a prominent subset of rapidly proliferating major histocompatibility complex (MHC) II-dependent cells. In contrast, Ag-specific memory CD4 cells have a slow turnover rate and are MHC II independent. In irradiated hosts, these latter cells ignore IL-15 and expand in response to the elevated levels of IL-7 in the lymphopenic hosts. In contrast, in normal nonlymphopenic hosts where IL-7 levels are low, memory CD4 cells are heavily dependent on IL-15. Significantly, memory CD4(+) responsiveness to endogenous IL-15 reflects marked competition from other cells, especially CD8(+) and natural killer cells, and increases considerably after removal of these cells. Therefore, under normal physiological conditions, homeostasis of CD8(+) and CD4(+) memory cells is quite similar and involves IL-15 and IL-7.

An intense form of homeostatic proliferation of naive CD8+ cells driven by IL-2.

In conditions of T lymphopenia, interleukin (IL) 7 levels rise and, via T cell receptor for antigen-self-major histocompatibility complex (MHC) interaction, induce residual naive T cells to proliferate. This pattern of lymphopenia-induced "homeostatic" proliferation is typically quite slow and causes a gradual increase in total T cell numbers and differentiation into cells with features of memory cells. In contrast, we describe a novel form of homeostatic proliferation that occurs when naive T cells encounter raised levels of IL-2 and IL-15 in vivo. In this situation, CD8(+) T cells undergo massive expansion and rapid differentiation into effector cells, thus closely resembling the T cell response to foreign antigens. However, the responses induced by IL-2/IL-15 are not seen in MHC-deficient hosts, implying that the responses are driven by self-ligands. Hence, homeostatic proliferation of naive T cells can be either slow or fast, with the quality of the response to self being dictated by the particular cytokine (IL-7 vs. IL-2/IL-15) concerned. The relevance of the data to the gradual transition of naive T cells into memory-phenotype (MP) cells with age is discussed.

A prospective, randomized controlled preclinical trial to evaluate different formulations of biphasic calcium phosphate in combination with a hydroxyapatite collagen membrane to reconstruct deficient alveolar ridges.

Many patients and clinicians would prefer a synthetic particulate bone replacement graft, but most available alloplastic biomaterials have limited osteogenic potential. An alloplast with increased regenerative capacity would be advantageous for the treatment of localized alveolar ridge defects. This prospective, randomized controlled preclinical trial utilized 6 female foxhounds to analyze the osteogenic impact of different formulations of biphasic calcium phosphate (BCP) in combination with an hydroxyapatite-collagen membrane and their ability to reconstruct deficient alveolar ridges for future implant placement. The grafted sites were allowed to heal 3 months, and then trephine biopsies were obtained to perform light microscopic and histomorphometric analyses. All treated sites healed well with no early membrane exposure or adverse soft tissue responses during the healing period. The grafted sites exhibited greater radiopacity than the surrounding native bone with BCP particles seen as radiopaque granules. The graft particles appeared to be well-integrated and no areas of loose particles were observed. Histologic evaluation demonstrated BCP particles embedded in woven bone with dense connective tissue/marrow space. New bone growth was observed around the graft particles as well as within the structure of the graft particulate. There was intimate contact between the graft particles and newly formed bone, and graft particles were bridged by the newly formed bone in all biopsies from the tested groups. The present study results support the potential of these BCP graft particulates to stimulate new bone formation. Clinical studies are recommended to confirm these preclinical findings.

The clinical and histologic outcome of dental implant in large ridge defect regenerated with alloplast: a randomized controlled preclinical trial.

A basic tenet of successful osseointegration is that the implant resides in a sufficient quality and quantity of bone to ensure bone contact and thus stabilization. A prospective, randomized controlled preclinical trial was conducted to evaluate the bone-to-implant contact (BIC) when placing implants in bone regenerated by 3 different combinations of biphasic calcium phosphate (BCP). Dental implants were placed into the regenerated ridges of 6 female foxhounds; the ridges were reconstructed with different formulations of BCP in combination with an hydroxyapatite collagen membrane. They were retrieved after 3 months to perform light microscopic and histomorphometric analyses. Implants in each group appeared to be stable and osseointegrated. Light microscopic evaluation revealed tight contacts between the implant threads with the surrounding bone for all 4 groups. The mean BIC ranged from 64.7% to 73.7%. This preclinical trial provided clinical and histologic evidence to support the efficacy of all 3 formulations of BCP to treat large alveolar ridge defects to receive osseointegrated dental implants.

The long-term success of periodontal regeneration: a 10-year follow-up case report.

OBJECTIVE: The predictability and long-term success of periodontal regeneration begins with oral hygiene education, disease management, and an individually tailored periodontal maintenance protocol. The treatment outcomes could be enhanced when biologics and bone grafts are combined. The aim of this report was to describe the outcome of two complex infrabony defects in the same patient treated with recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and freeze-dried bone allograft (FDBA) over 10 years. CASE PRESENTATION: Two complex infrabony defects were treated following guided tissue regeneration principles and procedures. Full-thickness flaps were raised to allow visualization of the defects. The areas were debrided, and exposed root surfaces were planed. FDBA and rhPDGF-BB were combined to fill both defects. A collagen membrane was used over the bone graft in one case. The flaps were reapproximated to achieve primary closure. The patient was seen for regular periodontal maintenance visits and clinical and radiographic follow-ups over 10 years. Throughout the examination periods, the probing depths improved without bleeding on probing, and there was radiographic evidence of bone regeneration. CONCLUSION: The growth factor-infused bone graft was successfully utilized for periodontal regeneration in complex bony defects.

The management of an oral pyogenic granuloma around osseointegrated dental implants.

INTRODUCTION: Oral pyogenic granulomas (PGs) presenting in association with dental implants are uncommon occurrences. While tooth-associated PGs are well-documented in the literature, there are only seven case reports with biopsy-confirmed diagnoses of PG related to dental implants. This case report details the treatment of an intraoral PG related to dental implants that had been osseointegrated and asymptomatic for 10 years. CASE PRESENTATION: A 39-year-old female presented with a hyperplastic erythematous mass that encompassed the dental implants in the position of the maxillary central incisors. Surgical exploration of the site revealed nonintegrated, particulate bone material distributed throughout the peri-implant tissues approximating the granuloma. Treatment involved surgical excision of the lesion, elimination of all nonintegrated bone material, and implant surface debridement. Laser therapy was later used to manage a recurrence. Histology of the biopsied tissue confirmed the diagnosis of PG and described the presence of multiple exogenous, refractile, particulate materials in the specimen. CONCLUSION: The combination of surgical excision, implant debridement, and conservative laser therapy resulted in the elimination of a dental implant-related PG and successful soft tissue management. The localized presence of nonintegrated particulate bone material surrounding the granuloma appears to have functioned as a chronic irritant to the peri-implant soft tissues over time and is likely, along with oral bacteria, the primary etiological agents. KEY POINTS: Why is this case new information? There is a paucity of reports describing the management of dental implant-related pyogenic granulomas especially in the esthetic region. The present case demonstrates that particulate bone materials used in guided bone regeneration have the capacity to behave as a low-grade irritant to the gingival tissues. It also demonstrates the successful elimination of the tissues and management of the peri-implant soft tissues for an esthetic result. What are the keys to successful management of this case? The key to successful management of this case was adequate removal of the exogenous irritant, proper implant surface debridement, and decontamination and adequate gingivoplasty to remove all residual hyperplastic granulomatous tissues. Additionally, patient education and appropriate oral hygiene instructions were important to proper healing and maintenance of the area. What are the primary limitations to success in this case? The ambiguity of the clinical boundaries of PGs makes it challenging to guarantee complete excision beyond the base of the lesion, leading to recurrence.

Gas Plasma Treatment Improves Titanium Dental Implant Osseointegration-A Preclinical In Vivo Experimental Study.

Recent technological advancements led to the development of various plasma-based technologies for post-packaging modifications. The purpose of the present preclinical in vivo study was to assess the safety and efficacy of a novel chairside nonthermal gas plasma treatment for enhancing osseointegration of titanium implants. Six male mixed foxhounds underwent extraction of mandibular premolars and first molars, and the sockets healed for 42 days. Canine mandibles were randomized to receive either plasma-treated (test) or non-plasma-treated (control) dental implants. A total of 36 implants were placed in six animals, and they were sacrificed at 2 weeks (two animals), 4 weeks (two animals), and 6 weeks (two animals) after the implant surgery. When the radiographic analysis was performed, the changes in bone level were not statistically significant between the two groups at 2 weeks and 4 weeks. The difference became significant at 6 weeks (p = 0.016), indicating more bone loss from baseline to 6 weeks for the control group. The bone-to-implant contact (BIC) appeared to be higher for the test groups at all time points, and the BIC was significantly higher for the test group at 4 weeks (p = 0.046). In conclusion, this study underscored the potential of nonthermal plasma treatment in enhancing implant osseointegration.

The Guided Bone Regeneration of a Large, Non-Contained, Perforated Maxillary Anterior Perforation Defect: A Case Report.

The reconstruction of alveolar ridge defects can be challenging, especially when the lesion is large, non-contained, and located in the esthetic region. The present report describes the guided bone regeneration (GBR) procedure and prosthetic rehabilitation of a severe perforation defect in the anterior maxilla. Clinical and radiographic evaluation of the lesion indicated an endodontic-periodontal origin, and biopsy results confirmed the absence of malignancy. GBR was performed with the use of cortical mineralized freeze-dried bone allograft (FDBA) combined with recombinant human platelet derived growth factor BB (rhPDGF-BB) and a resorbable collagen membrane without the use of tenting or fixation screws. At six months post-GBR, cone beam computed tomography (CBCT) revealed adequate bone fill for the placement of 4.1 x 10 mm or 4.1 x 12 mm dental implants. The implant surgery was fully guided with a two-stage approach. After a ten-month of healing phase, the implants were loaded with a screw-retained porcelain bridge. The staged GBR approach using a combination of FDBA, rhPDGF-BB, and a resorbable membrane without the use of tenting or fixation screws resulted in significant bone fill, successful implant placement, and a functional and esthetic implant-supported prosthesis.

A Prospective Clinical Assessment of BioHorizons Tissue-Level Implants.

This investigation was designed to evaluate crestal bone stability and soft tissue maintenance to Laser-Lok tapered tissue-level implants. Twelve patients presenting with an edentulous site adequate for the placement of two implants were recruited from four dental offices (2 to 4 patients per office). Each patient received two Laser-Lok tissue-level implants placed with a 3-mm interimplant distance according to a surgical stent. The implants were placed so that the Laser-Lok zone sat at the junction between hard and soft tissues. A total of 24 implants were placed, and all achieved satisfactory crestal bone stability and soft tissue maintenance 1 year after receiving the final prosthetic restoration.

Human histologic evaluation of the use of the dental putty for bone formation in the maxillary sinus: case series.

A proof-of-principle study was conducted to assess the safety and efficacy of dental putty as an alternative sinus augmentation biomaterial. Six healthy patients requiring a total of 10 sinus augmentations received sinus augmentations. All patients volunteered and signed an informed consent based on the Helsinki declaration of 1975, as revised in 2000. The sinus augmentation was performed under local anesthesia with a mucoperiosteal flap elevated to expose the buccal wall of the maxillary sinus. The space was then filled with the dental putty in several increments, and the window was covered with an absorbable collagen membrane. Biopsies were harvested from all 10 treated sinuses using a 3-mm trephine bur at the time of implant placement at either 6 or at 9 months after sinus augmentation. All patients completed the study without complications, except for 1 patient who reported fistulas at 1 and 2 months after the surgery. Clinical reentry revealed that regenerated bone on the osteotomy site was soft and immature. The ground sections of the biopsied cores revealed minimum amounts of trabeculation surrounded by an abundant array of irregular-shaped residual alloplastic particles embedded in loose connective tissue. The present study's findings revealed inadequate bone formation, although the material appears to be bioinert as there is no elicitation of inflammatory response.