Development and evaluation of real-time quantitative PCR assays for detection of Phellinus noxius causing brown root rot disease.

Brown root rot disease (BRRD) is a highly destructive tree disease. Early diagnosis of BRRD has been challenging because the first symptoms and signs are often observed after extensive tissue colonization. Existing molecular detection methods, all based on the internal transcribed spacer (ITS) region, were developed without testing against global Phellinus noxius isolates, other wood decay fungi, or host plant tissues. This study developed SYBR Green real-time quantitative PCR (qPCR) assays for P. noxius. The primer pair Pn_ITS_F/Pn_ITS_R targets the ITS, and the primer pair Pn_NLR_F/Pn_NLR_R targets a P. noxius-unique group of homologous genes identified through a comparative genomics analysis. The homologous genes belong to the nucleotide-binding-oligomerization-domain-like receptor (NLR) superfamily. The new primer pairs and a previous primer pair G1F/G1R were optimized for qPCR conditions and tested for specificity using 61 global P. noxius isolates, five other Phellinus species, and 22 non-Phellinus wood decay fungal species. While all three primer pairs could detect as little as 100 fg (about 2.99 copies) of P. noxius genomic DNA, G1F/G1R had the highest specificity and Pn_NLR_F/Pn_NLR_R had the highest efficiency. To avoid false positives, the cutoff Cq values were determined as 34 for G1F/G1R, 29 for Pn_ITS_F/Pn_ITS_R, and 32 for Pn_NLR_F/Pn_NLR_R. We further validated these qPCR assays using Ficus benjamina seedlings artificially inoculated with P. noxius, six tree species naturally infected by P. noxius, rhizosphere soil, and bulk soil. The newly developed qPCR assays provide sensitive detection and quantification of P. noxius, which is useful for long-term monitoring of BRRD status.

Can Male Patient's Age Affect the Cortical Bone Thickness of Jawbone for Dental Implant Placement? A Cohort Study.

Dental implants are among the most common treatments for missing teeth. The thickness of the crestal cortical bone at the potential dental implant site is a critical factor affecting the success rate of dental implant surgery. However, previous studies have predominantly focused on female patients, who are at a high risk of osteoporosis, for the discussion of bone quality and quantity at the dental implant site. This study aimed to investigate the effect of male patients' age on the crestal cortical bone of the jaw at the dental implant site by using dental cone-beam computed tomography (CBCT). This study performed dental CBCT on 84 male patients of various ages to obtain tomograms of 288 dental implant sites at the jawbone (41 sites in the anterior maxilla, 95 in the posterior maxilla, 59 in the anterior mandible, and 93 in the posterior mandible) for measuring the cortical bone thickness. A one-way analysis of variance and Scheffe's test were performed on the measurement results to compare the cortical bone thickness at implant sites in the four jaw areas. The correlation between male patient age and cortical bone thickness at the dental implant site was determined. The four jaw areas in order of the cortical bone thickness were as follows: posterior mandible (1.07 ± 0.44 mm), anterior mandible (0.99 ± 0.30 mm), anterior maxilla (0.82 ± 0.32 mm), and posterior maxilla (0.71 ± 0.27 mm). Apart from dental implant sites in the anterior and posterior mandibles, no significant correlation was observed between male patients' age and the cortical bone thickness at the dental implant site.

Association between Age of Menopause and Thickness of Crestal Cortical Bone at Dental Implant Site: A Cross-Sectional Observational Study.

Satisfactory host bone quality and quantity promote greater primary stability and better osseointegration, leading to a high success rate in the use of dental implants. However, the increase in life expectancy as a result of medical advancements has led to an aging population, suggesting that osteoporosis may become a problem in clinical dental implant surgery. Notably, relative to the general population, bone insufficiency is more common in women with post-menopausal osteoporosis. The objective of this study was to compare the thickness of the crestal cortical bone at prospective dental implant sites between menopausal and non-menopausal women. Prospective dental implant sites in the jawbone were evaluated in two groups of women: a younger group (<50 years old), with 149 sites in 48 women, and an older group (>50 years old) with 191 sites, in 37 women. The thickness of the crestal cortical bone at the dental implant site was measured based on each patient's dental cone-beam computed tomography images. For both groups, one-way analysis of variance and Tukey's post-test were used to assess the correlation between cortical bone thickness and the presence of implants in the four jawbone regions. Student's t-test was further used to compare differences between the older and younger groups. From the retrospective study results, for both groups, thickness of the crestal cortical bone was the highest in the posterior mandible, followed by anterior mandible, anterior maxilla, and posterior maxilla. Compared with the younger group, the older group had a lower mean thickness of the crestal cortical bone. Among the four regions, however, only in the posterior maxilla was the crestal cortical bone significantly thinner in the older group than in the younger group.

Variations in crestal cortical bone thickness at dental implant sites in different regions of the jawbone.

BACKGROUND: Dental implants have become reliable and predictable tools for treating missing teeth. The survival rate of dental implants is markedly influenced by the host bone quality and quantity of the jawbone. A better host bone provides higher initial stability of the dental implant, resulting in better osseointegration and a higher success rate. Host bone quality and quantity are determined by the crestal cortical bone thickness and inner cancellous bone density. OBJECTIVE: The purpose of this study was to determine the crestal cortical bone thickness at dental implant sites in different regions of the jawbone through the use of dental cone-beam computed tomographic (CBCT) images. MATERIALS AND METHODS: A total of 661 dental implant sites (81 in the anterior mandible, 122 in the anterior maxilla, 224 in the posterior mandible, and 234 in the posterior maxilla) were obtained from the jawbones of 173 humans. The data were subjected to statistical analysis to determine any correlation between crestal cortical bone thicknesses and jawbone regions using one-way analysis of variance with Tukey's post-test. RESULTS: The crestal cortical bone thicknesses at dental implant sites in the four regions decreased in the following order: posterior mandible (1.07 ± 0.47 mm, mean ± SD) >anterior mandible (0.99 ± 0.36 mm) >anterior maxilla (0.82 ± 0.30 mm) >posterior maxilla (0.75 ± 0.35 mm). CONCLUSION: The dental CBCT data demonstrate that crestal cortical bone thickness varies markedly between dental implant sites in the four regions of the jawbone.

In vitro antibacterial activity and cytocompatibility of bismuth doped micro-arc oxidized titanium.

Chemical manipulations of the implant surface produce a bactericidal feature to prevent infections around dental implants. Despite the successful use of bismuth against mucosal and dermis infections, the antibacterial effect of bismuth in the oral cavity remains under investigation. The aim of this study was to evaluate the antibacterial activities of bismuth compounds against Actinobacillus actinomycetemcomitans, Staphylococcus mutans, and methicillin-resistant Staphylococcus aureus (MRSA), and to investigate the antimicrobial effects of bismuth doped micro-arc oxidation (MAO) titanium via an agar diffusion test. Cell viability, alkaline phosphatase activity, and mineralization level of MG63 osteoblast-like cells seeded on the coatings were evaluated at 1, 7, and 14 days. The results demonstrate that bismuth nitrate possess superior antibacterial activity when compared with bismuth acetate, bismuth subgallate, and silver nitrate. The bismuth doped MAO coating (contained 6.2 atomic percentage bismuth) had good biological affinities to the MG63 cells and showed a higher antibacterial efficacy against Actinobacillus actinomycetemcomitans and MRSA, where the reduction rates of colony numbers is higher than that of the control group by 1.5 and 1.9 times, respectively. These in vitro evaluations demonstrate that titanium implants with bismuth on the surface may be useful for better infection control.