Longitudinal Microbiome Changes in Supragingival Biofilm Transcriptomes Induced by Orthodontics.

INTRODUCTION: Common oral diseases are known to be associated with dysbiotic shifts in the supragingival microbiome, yet most oral microbiome associations with clinical end points emanate from cross-sectional studies. Orthodontic treatment is an elective procedure that can be exploited to prospectively examine clinically relevant longitudinal changes in the composition and function of the supragingival microbiome. METHODS: A longitudinal cohort study was conducted among 24 adolescent orthodontic patients who underwent saliva and plaque sampling and clinical examinations at time points: before fixed appliance bonding and at 1, 6, and 12 wk thereafter. Clinical indices included bleeding on probing (BOP), mean gingival index (GI), probing depths (PDs), and plaque index (PI). To study the biologically (i.e., transcriptionally) active microbial communities, RNA was extracted from plaque and saliva for RNA sequencing and microbiome bioinformatics analysis. Longitudinal changes in microbiome beta diversity were examined using PERMANOVA tests, and the relative abundance of microbial taxa was measured using Kruskal-Wallis tests, Wilcoxon rank-sum tests, and negative binomial and zero-inflated mixed models. RESULTS: Clinical measures of oral health deteriorated over time-the proportion of sites with GI and PI ≥1 increased by over 70% between prebonding and 12 wk postbonding while the proportion of sites with PD ≥4 mm increased 2.5-fold. Streptococcus sanguinis, a health-associated species that antagonizes cariogenic pathogens, showed a lasting decrease in relative abundance during orthodontic treatment. Contrarily, caries- and periodontal disease-associated taxa, including Selenomonas sputigena, Leptotrichia wadei, and Lachnoanaerobaculum saburreum, increased in abundance after bonding. Relative abundances of Stomatobaculum longum and Mogibacterium diversum in prebonding saliva predicted elevated BOP 12 wk postbonding, whereas Neisseria subflava was associated with lower BOP. CONCLUSIONS: This study offers insights into longitudinal community and species-specific changes in the supragingival microbiome transcriptome during fixed orthodontic treatment, advancing our understanding of microbial dysbioses and identifying targets of future health-promoting clinical investigations. KNOWLEDGE TRANSFER STATEMENT: Bonding braces was associated with subsequent changes in the oral microbiome characterized by increases in disease-associated species, decreases in health-associated species, and worsened clinical measures of oral health.

Porcine bladder extracellular matrix for closure of a large defect in a burn contracture release.

Porcine bladder extracellular matrix (PBEM) is an innovative wound healing alternative to traditional wound closure and reconstruction. By stimulating blood vessel formation and chemotaxis of progenitor cells to the site of injury, it promotes a unique healing environment favouring regeneration of native tissue over scar formation. This is the first clinical report describing the novel use of PBEM scaffold material to close a large defect resulting from a burn contracture release. The benefits of this method are the improved functional and cosmetic result. PBEM-moderated tissue regeneration may serve a valuable role in burn reconstruction.

Short-term surgical missions: joining hands with local providers to ensure sustainability.

Short-term surgical missions may appear to fill a void in surgical capacity in the developing world, but may inadvertently also disrupt well-established local healthcare systems. The surgical providers of an East African hospital developed suggestions for improving these missions so that they can benefit visitors, local providers and patients alike.

The acute retinal necrosis syndrome. Part 2: Histopathology and etiology.

The acute retinal necrosis syndrome is manifested by diffuse uveitis, vitritis, retinal vasculitis, and acute necrotizing retinitis (see Part 1). We studied the histopathology and electron microscopic findings of an eye enucleated from a 67-year-old man with typical acute retinal necrosis. Histology showed profound acute necrosis of the retina, retinal arteritis, and eosinophilic intranuclear inclusions in retinal cells. Electron microscopy demonstrated a herpes group virus in all layers of affected retina. The implications of these findings for antiviral and other treatments are discussed.

Ocular motility complications following intranasal surgery.

The ocular motility problem of two patients following intranasal surgery is examined. The patients were studied by eye movement records and ultrasonography. Surgery in both cases revealed a defect of the medial orbital wall with scar tissue incarcerated in the defect.

Two-dimensional monochromatic x-ray imaging of laserproduced plasmas.

A slitted crystal spectrograph has been used to produce two-dimensional, spatially resolved, monochromatic images of laser-irradiated targets. The technique is described, and examples are presented for comparison with corresponding pinhole photographs. Resolution along and transverse to the dispersion are determined by the crystal rocking angle and geometry of the spectrograph, respectively. One important application of this technique would be to radiograph hot, compressed targets, since the slitted spectrograph behaves as a filtered rectangular pinhole.

The long-term effects of iridectomy for primary acute angle-closure glaucoma.

Forty-nine eyes were treated with iridectomy for primary acute angle-closure glaucoma. Forty asymptomatic, normotensive fellow eyes were similarly treated. The duration of follow-up after surgery was 52.3 +/- 3.6 months. Thirty-seven (76%) of the eyes with acute attacks were cured by iridectomy alone and required no medical therapy. Twelve eyes (24%) developed increased intraocular pressure following iridectomy, but only one eye (2%) required filtering surgery. Eighty-eight percent of the asymptomatic, normotensive fellow eyes required no subsequent therapy, and none developed visual field defects. Visual acuity was unchanged in 22 of 49 (45%) of the acutely involved eyes and decreased more than six lines in 11 (22%) eyes. In the 40 fellow eyes, visual acuity was unchanged in 63% and decreased more than six lines in only one (2%) eye.

Cyclocryotherapy in neovascular glaucoma.

To determine the long-term effects of cyclocryotherapy, we conducted a follow-up with a mean of 24.9 +/- 13.9 months in 50 eyes of 46 patients with neovascular glaucoma. On final examination, intraocular pressure in 16 (32%) of the eyes was greater than 26 mm Hg and in 17 (34%), less than or equal to 25 mm Hg; 17 (34%) developed phthisis bulbi. Enucleation was performed in three of the eyes. Anterior segment necrosis occurred immediately postoperatively in four eyes. Twenty-four of 41 eyes (58.5%) with vision lost light perception during our study. All patients were comfortable except the three who required enucleation.