Finding Better Ways to Perform Graftless Full Rehabilitation of a Compromised Maxilla: New Platform-Switched Zygomatic Implants Placed Extra-Sinus Improve Prosthetic Restoration-A Preliminary Study of 25 Cases and 85 Implants.

Standard treatment for full rehabilitation of compromised maxillae with regular implants includes sinus elevation grafting, a minimum of two to three surgeries, and a minimum treatment time of 9 to 15 months. Zygomatic implants are a viable alternative. However, prosthetic restorations have been compromised due to abutments emerging on the palate. The purpose of this study was to find ways that abutments will emerge on the ridge (occlusal surface). The presented results show it can be done if zygomatic implants are placed in the sinus wall (extra-sinus) and use an internal, conical connection with platform-switching and 45-degree abutments. Thus, marginal tissue prognosis and primary stability may also be improved by adding coronal threads to an implant design. These improvements, if confirmed in longer follow-ups and further studies, may encourage more graftless rehabilitations of severely compromised maxillae, reducing the number of surgeries and overall treatment time.

Evaluation of circulating CD34+ stem cells in peripheral venous blood in patients with varying degrees of periodontal disease.

INTRODUCTION: Periodontal disease presents a challenge for modern medicine, and research on the use of stem cells as a treatment is currently underway. MATERIAL AND METHODS: The study included 45 patients who were given a thorough physical examination. Additionally, an evaluation of their medical history of the disease, degree of progression of periodontal disease, and the level of CRP in the blood was carried out. Patients were divided into 4 groups: 4 patients were in the first group with no periodontal disease, 8 patients in the second group with a moderate level, 20 patients in the third group with an advanced level, and 13 patients in the fourth group were toothless. For each group, the use of stem cells as a treatment of antibody-labeled CD34+ stem cells, lymphocytes, and leukocytes was conducted. RESULTS: A statistically significant positive correlation was observed in CD34+ stem cells in proportion to lymphocytes in the moderate (0.80), in the advanced (0.75), and in the toothless groups (0.70). The ratio of CD34+ stem cells to leukocytes was statistically significant in the toothless group (0.92) and in the advanced group (0.91). A statistically significant increase was noted in the level of CRP in the previously mentioned groups of patients, and the highest concentration of CD34+ stem cells in the advanced group. CONCLUSIONS: The highest concentration of CD34+ cells was observed in the group of patients with advanced periodontal disease.

Analysis of IL-1ß, CXCL8, and TNF-α levels in the crevicular fluid of patients with periodontitis or healthy implants.

BACKGROUND: Our study aimed to assess the level of IL-1ß, CXCL8, and TNF-α in peri-implant sulcular fluid (PISF) collected from patients with no clinical symptoms of mucositis or peri-implantitis and compare them with cytokine concentration in gingival crevicular fluid (GCF) acquired from patients with healthy periodontium and those with varying severity of periodontitis. METHODS: A total of 189 subjects were included in the study, and GCF/PISF samples were checked for IL-1ß, CXCL8, and TNF-α levels using an ELISA test. RESULTS: The IL-1ß level in PISF in patients with implants was significantly lower than in GCF in patients with mild, moderate, or severe periodontitis. The CXCL8 level in PISF was considerably lower than in patients with moderate periodontitis. The TNF-α level in PISF in patients with implants was markedly higher compared to subjects with healthy periodontium or patients with mild periodontitis. CONCLUSION: Analysis of cytokine levels may help describe the pathogenesis and early diagnosis of peri-implantitis and prevision in high-risk patients.

Archaea Occurrence in the Subgingival Biofilm in Patients with Peri-implantitis and Periodontitis.

This study aimed to determine the prevalence and diversity of archaea and select bacteria in the subgingival biofilm of patients with peri-implantitis in comparison to patients with unaffected implants and patients with periodontitis. Samples of subgingival biofilm from oral sites were collected for DNA extraction (n = 139). A 16S rRNA gene-based polymerase chain reaction assay was used to determine the presence of archaea and select bacteria. Seven samples were selected for direct sequencing. Archaea were detected in 10% of samples from peri-implantitis sites, but not in samples from the unaffected dental implant. Archaea were present in 53% and 64% of samples from mild and moderate/advanced periodontitis sites, respectively. The main representative of the Archaea domain found in biofilm from periodontitis and peri-implantitis sites was Methanobrevibacter oralis. The present results revealed that archaea are present in diseased but not healthy implants. It was also found that archaea were more abundant in periodontitis than in peri-implantitis sites. Hence, the potential role of archaea in peri-implantitis and periodontitis should be taken into consideration.

Platform switch hybrid zygoma implants improve prosthetics and marginal bone protection after extra-sinus placement.

PURPOSE: The aim of our studdy is clinical evaluation of Platform switch hybrid zygoma implants. MATERIALS AND METHODS: 117 zygomatic implants were followed up during this time. They included 55 Brånemark System zygoma implants, 38 Noris implants, and 24 novel iRES hybrid implants with platform switch. RESULTS: Bone quality and quantity are the prerequisite for successful implant treatment. Zygomatic implants are intended for patients with severely resorbed maxilla that cannot accommodate conventional implants without prior extensive bone grafting. Such regenerative procedures, like sinus lifts, prolong implant rehabilitation to several months (12-18). Furthermore, extensive grafts are less predictable showing varying degrees of graft resorption. Zygoma implants enable full, often immediate, reconstruction of the upper dental arch without the need for sinus lift treatment. The original zygoma protocol runs the implants through the sinus, requires general anesthesia, and positions the prosthetic platform of the implants on the palate, which makes prosthesis cumbersome. It also induces risk for post-op sinusitis. Extra-sinus approach with novel zygoma hybrid implants bypasses sinuses and positions the implant prosthetic platform on the crest allowing for same good prosthetics as on conventional dental implants. Furthermore, crestal threads and a platform-switch, of the novel zygoma design, increase implant anchorage and minimize marginal bone loss. The study presents evolution of zygoma implant rehabilitation protocol and zygoma implant design in our clinical practice over 15 years (2004-2019). CONCLUSION: Extra-sinus zygomatic implant placement lowers the risk of post-op sinusitis and makes procedure possible to be done in local anesthesia.

Extra-Sinus Zygomatic Implants to Avoid Chronic Sinusitis and Prosthetic Arch Malposition: 12 Years of Experience.

This report retrospectively at the 12-year follow-up results of the treatment and rehabilitation of edentulous maxillae, applying extra-sinus zygomatic implants alone or in combination with intra-sinus zygomatic implants. We recruited 22 patients with 35 zygomatic Brånemark system implants; 24 implants in the standard Brånemark protocol through the sinus and 11 extra-sinus implants outside the sinus. Additionally, 147 regular implants were placed. The minimum follow-up period was 50 months to a maximum of 152 months. The zygoma survival rate after 12 years was 97.15%. Chronic sinusitis occurred in 11.42% of patients. We lost 1 (2.85%) zygomatic implant placed through the sinus and none of those in the extra-sinus position. The survival rate of the regular implants was 93.87%. Chronic sinusitis occurred in 4 patients (11.42%) who received zygomatic implants using standard protocol through the sinus. None of the extra-sinus zygoma patients developed sinusitis. Peri-implantitis was detected with only 3 zygomatic implants. In the original P-I Brånemark zygoma protocol the implants were passing through the sinus, which resulted in chronic sinusitis in some patients and malposition of the prosthetic platform toward the palate. These complications can be avoided by the extra-sinus placement of zygoma implants as demonstrated in this study.

Evaluation of Metalloproteinase-8 Levels in Crevicular Fluid of Patients with Healthy Implants or Periodontitis.

Evaluation of periodontal and peri-implant tissue condition is mainly based on clinical examination and imaging diagnostics. Some data imply that Metalloproteinase-8 (MMP-8) level examination in peri-implant sulcular fluid (PISF) might be useful for evaluating the condition of peri-implant tissues and monitoring a development of peri-implant inflammation, including both mucositis and peri-implantitis. Hence, in this study, we decided to evaluate the level of MMP-8 in PISF obtained from patients without clinical symptoms of mucositis or peri-implantitis and compare it with MMP-8 level in gingival crevicular fluid (GCF) obtained from patients with healthy periodontium and those with varying severity of periodontitis. A total of 189 subjects were included in the study, and GCF/PISF samples were analysed for MMP-8 level by ELISA test. We documented that MMP-8 level in PISF obtained from patients without symptoms of mucositis or peri-implantitis was significantly higher not only than in GCF of periodontally healthy patients but also, which seems to be very interesting, than in GCF of patients with varying degrees of periodontal inflammation, consistent with earlier studies. Our observation might imply that monitoring of MMP-8 level in PISF could help to diagnose mucositis/peri-implantitis in an early stage, prior to clinical manifestations, which may allow for quick start of appropriate therapy.

The -5 A/G single-nucleotide polymorphism in the core promoter region of MT2A and its effect on allele-specific gene expression and Cd, Zn and Cu levels in laryngeal cancer.

Metallothioneins (MTs) are low molecular weight, cysteine-rich heavy metal-binding proteins which participate in the mechanisms of Zn homeostasis, and protect against toxic metals. MTs contain metal-thiolate cluster groups and suppress metal toxicity by binding to them. The aim of this study was to determine the -5 A/G (rs28366003) single-nucleotide polymorphism (SNP) in the core promoter region of the MT2A gene and to investigate its effect on allele-specific gene expression and Cd, Zn and Cu content in squamous cell laryngeal cancer (SCC) and non-cancerous laryngeal mucosa (NCM) as a control. The MT2A promoter region -5 A/G SNP was determined by restriction fragment length polymorphism using 323 SCC and 116 NCM. MT2A gene analysis was performed by quantitative real-time PCR. The frequency of A allele carriage was 94.2% and 91.8% in SCC and NCM, respectively, while G allele carriage was detected in 5.8% and 8.2% of SCC and NCM samples, respectively. As a result, a significant association was identified between the -5 A/G SNP in the MT2A gene with mRNA expression in both groups. Metal levels were analyzed by flame atomic absorption spectrometry. The significant differences were identified between A/A and both the A/G and G/G genotypes, with regard to the concentration of the contaminating metal. The Spearman rank correlation results showed that the MT2A expression and Cd, Zn, Cu levels were negatively correlated. Results obtained in this study suggest that -5 A/G SNP in MT2A gene may have an effect on allele-specific gene expression and accumulation of metal levels in laryngeal cancer.