Stability of anterior open bite cases treated with upper and lower extrusion arches in adults: a follow-up study.

OBJECTIVES: To investigate the post-treatment stability of anterior open bite (AOB) cases treated with upper and lower extrusion arches in adults. MATERIALS AND METHODS: 23 patients with AOB were treated with extrusion arches and evaluated for dentoskeletal changes using lateral cephalometric radiographs before treatment (T0), after treatment (T1), and 12 months post-treatment (T2). Patients received bondable tongue spurs and vacuum-formed retainers as post-treatment retention/stability measures for 12 months. Post-treatment stability was further assessed qualitatively by the Photographic Openbite Severity Index. RESULTS: All the cases showed positive overlap between the anterior teeth at the end of orthodontic treatment, and 20 of 23 treated patients attended the recall visit after 12 months. A total of 85% of the cases maintained positive overlap at least 1 year post-treatment, 10% showed edge-to-edge bite, and only 5% showed no overbite. CONCLUSIONS: Treatment of AOB in adults with extrusion arches proved to be stable 1 year post-treatment. Changes in the overbite after 1 year of follow-up were not significant.

Effect of maxillary and mandibular extrusion arches on dentoskeletal changes in adults with anterior open bite: a quantitative analysis.

OBJECTIVE: To quantify dentoskeletal changes accompanying the use of extrusion arches during the treatment of anterior open bite (AOB) in adults. MATERIALS AND METHODS: A total of 23 adult patients with an AOB of -3.05 mm ± 1.27 mm were treated with upper and lower extrusion arches after the alignment phase. Lateral cephalograms were taken before placement of the extrusion arch, immediately after closure of the open bite (T2), and at the end of orthodontic treatment (T3). Data were statistically analyzed using repeated-measures analysis of variance and the Bonferroni post hoc test for pairwise comparisons (α = 0.05). RESULTS: Successful closure of AOB, with an overall change in overbite of 4.73 ± 1.93 mm, was achieved in an average of 3.8 months and remained stable at T3. Upper and lower incisors were significantly extruded by 2.05 mm ± 0.72 mm and 2.54 mm ± 1.63 mm, respectively, and significantly retroclined by 6.36° ± 1.63° and 8.45° ± 3.83°, respectively, with a resultant increase in the interincisal angle of 12.80° ± 2.09°. Statistically significant intrusion and mesial tipping (P < .001) of the maxillary and mandibular first molars were observed at T2. Dentoskeletal changes remained stable at T3, except for a significant reduction of the mesial tipping of the maxillary and mandibular first molars. CONCLUSIONS: The combined use of maxillary and mandibular extrusion arches resulted in significant favorable dentoskeletal changes that led to the successful closure of AOB during a short duration of treatment.

Periodontal changes following distraction osteogenesis in patients with cleft lip and palate: a clinical trial.

OBJECTIVES: To evaluate inflammatory mediator levels and periodontal changes following distraction osteogenesis (DO) in patients with cleft lip and palate (CLP) using mid-maxillary distraction (MMD). MATERIALS AND METHODS: A total of 20 healthy patients with CLP with Class III malocclusion were included. Segmental forward advancement of the anterior maxilla from the second premolars on both sides using DO was performed. A custom-made, tooth-borne distractor connecting buccal molar segments to the anterior maxilla was used for 7 days with 0.5-mm distraction for the first 2 days and then increased to 1 mm daily until overcorrection. Crevicular interleukin IL-1ß and tumor necrosis factor TNF-α levels were measured during distraction. Periodontal clinical parameters and indices were recorded at baseline and 3 and 6 months postoperatively. Soft tissue healing was evaluated histologically at 2 and 4 weeks after distraction. RESULTS: The periodontal parameters remained stable during the follow-up periods. Insignificant increases in the level of inflammatory cytokines compared with the control were observed. Histological findings revealed mild inflammatory and structural changes in the gingiva immediately after distraction, whereas regeneration was noticed after 4 weeks. CONCLUSIONS: MMD was an effective technique in treating patients with CLP, leading to new bone and soft tissue formation without significant detrimental effect on the periodontium of the adjacent teeth.

Quantitative Evaluation of Palatal Lengthening After Cleft Palate Repair When a Buccal Flap Is Routinely Combined With Furlow's Z-Plasty.

INTRODUCTION: The use of a buccinator myomucosal flap in combination with Furlow's Z-plasty during primary and secondary palatal repairs has been proposed by many authors to overcome some of the limitations of Furlow's technique. However, there have been no studies that quantitatively measured the effective palatal lengthening when the buccal flap is added. PATIENTS AND METHODS: The buccal flap is routinely used during primary palate repair in order to fill the gap between the hard palate and reoriented palatal muscle sling. The soft palatal length was measured in the midline from the posterior edge of the hard palate to the base of the uvula. All patients were measured before starting the surgery and just after palatal closure in the standard position for cleft palate repair. RESULTS: Seventy-three patients with cleft palate who were candidates for primary repair were included. The mean age at the time of operation was 11.4 ± 3.5 months. The mean preoperative palatal length was 21.36 ± 3.529 mm, whereas the mean postoperative palatal length was 29.64 ± 4.171) mm. The mean palatal length change was 8.29 ± 2.514 mm (P < 0.000). CONCLUSIONS: The Combined use of a buccinator myomucosal flap with modified Furlow's Z-plasty in primary cleft palate repair has proven effective for palatal lengthening and achieved tensionless closure without the need for relaxing incision. It also provided a pliable soft tissue attachment of the palatal muscles to the hard palate allowing for better muscle function and mobility.

Transgenic Mice Overexpressing Human Alpha-1 Antitrypsin Exhibit Low Blood Pressure and Altered Epithelial Transport Mechanisms in the Inactive and Active Cycles.

Human alpha-1 antitrypsin (hAAT) is a versatile protease inhibitor, but little is known about its targets in the aldosterone-sensitive distal nephron and its role in electrolyte balance and blood pressure control. We analyzed urinary electrolytes, osmolality, and blood pressure from hAAT transgenic (hAAT-Tg) mice and C57B/6 wild-type control mice maintained on either a normal salt or high salt diet. Urinary sodium, potassium, and chloride concentrations as well as urinary osmolality were lower in hAAT-Tg mice maintained on a high salt diet during both the active and inactive cycles. hAAT-Tg mice showed a lower systolic blood pressure compared to C57B6 mice when maintained on a normal salt diet but this was not observed when they were maintained on a high salt diet. Cathepsin B protein activity was less in hAAT-Tg mice compared to wild-type controls. Protein expression of the alpha subunit of the sodium epithelial channel (ENaC) alpha was also reduced in the hAAT-Tg mice. Natriuretic peptide receptor C (NPRC) protein expression in membrane fractions of the kidney cortex was reduced while circulating levels of atrial natriuretic peptide (ANP) were greater in hAAT-Tg mice compared to wild-type controls. This study characterizes the electrolyte and blood pressure phenotype of hAAT-Tg mice during the inactive and active cycles and investigates the mechanism by which ENaC activation is inhibited in part by a mechanism involving decreased cathepsin B activity and increased ANP levels in the systemic circulation.

Multidisciplinary management of a fused maxillary incisor: Case report with 5-year follow-up.

Detailed treatment planning and execution are crucial if regenerative approaches are to be attempted to retain fused permanent teeth. Long-term follow-up is necessary to monitor the stability of the final outcome, both esthetically and functionally.

Limitation in Controlling the Morphology of Mammalian Vero Cells Induced by Cell Division on Asymmetric Tungsten-Silicon Oxide Nanocomposite.

Engineered nanomaterials are often used in tissue engineering applications to influence and manipulate the behavior of cells. Recently, a number of tungsten-silicon oxide nanocomposite devices containing equal width (symmetric) tungsten and silicon oxide parallel line comb structures were developed and used by our group. The devices induced over 90% of seeded cells (Vero) to align within ±20° of the axes of 10 µm wide tungsten lines. Furthermore, a mathematical model was successfully developed to predict this alignment behavior and forecast the minimum width of isolated tungsten lines required to induce such behavior. However, the mechanism by which the widths of the symmetrical tungsten and silicon oxide lines induce the alignment behavior is still unknown. Furthermore, the model was never tested on more complex asymmetrical structures. Herewith, experiments were conducted with mammalian cells on complex asymmetrical structures with unequal tungsten and silicon oxide line widths. Results showed that the model could be extended to more complex pattern structures. In addition, cell morphology on the patterned structures reset during cell division because of mitotic rounding, which reduced the population of cells that elongated and aligned on the tungsten lines. Ultimately, we concluded that it was impossible to achieve a 100% alignment with cells having unsynchronized cell cycles because cell rounding during mitosis took precedence over cell alignment; in other words, internal chemical cues had a stronger role in cell morphology than external cues.

Nanoscale-Textured Tantalum Surfaces for Mammalian Cell Alignment.

Tantalum is one of the most important biomaterials used for surgical implant devices. However, little knowledge exists about how nanoscale-textured tantalum surfaces affect cell morphology. Mammalian (Vero) cell morphology on tantalum-coated comb structures was studied using high-resolution scanning electron microscopy and fluorescence microscopy. These structures contained parallel lines and trenches with equal widths in the range of 0.18 to 100 µm. Results showed that as much as 77% of adherent cell nuclei oriented within 10° of the line axes when deposited on comb structures with widths smaller than 10 µm. However, less than 20% of cells exhibited the same alignment performance on blanket tantalum films or structures with line widths larger than 50 µm. Two types of line-width-dependent cell morphology were observed. When line widths were smaller than 0.5 µm, nanometer-scale pseudopodia bridged across trench gaps without contacting the bottom surfaces. In contrast, pseudopodia structures covered the entire trench sidewalls and the trench bottom surfaces of comb structures with line-widths larger than 0.5 µm. Furthermore, results showed that when a single cell simultaneously adhered to multiple surface structures, the portion of the cell contacting each surface reflected the type of morphology observed for cells individually contacting the surfaces.

Pattern-Dependent Mammalian Cell (Vero) Morphology on Tantalum/Silicon Oxide 3D Nanocomposites.

The primary goal of this work was to investigate the resulting morphology of a mammalian cell deposited on three-dimensional nanocomposites constructed of tantalum and silicon oxide. Vero cells were used as a model. The nanocomposite materials contained comb structures with equal-width trenches and lines. High-resolution scanning electron microscopy and fluorescence microscopy were used to image the alignment and elongation of cells. Cells were sensitive to the trench widths, and their observed behavior could be separated into three different regimes corresponding to different spreading mechanism. Cells on fine structures (trench widths of 0.21 to 0.5 µm) formed bridges across trench openings. On larger trenches (from 1 to 10 µm), cells formed a conformal layer matching the surface topographical features. When the trenches were larger than 10 µm, the majority of cells spread like those on blanket tantalum films; however, a significant proportion adhered to the trench sidewalls or bottom corner junctions. Pseudopodia extending from the bulk of the cell were readily observed in this work and a minimum effective diameter of ~50 nm was determined for stable adhesion to a tantalum surface. This sized structure is consistent with the ability of pseudopodia to accommodate ~4⁻6 integrin molecules.

What's Happening on the Other Side? Revealing Nano-Meter Scale Features of Mammalian Cells on Engineered Textured Tantalum Surfaces.

Advanced engineered surfaces can be used to direct cell behavior. These behaviors are typically characterized using either optical, atomic force, confocal, or electron microscopy; however, most microscopic techniques are generally restricted to observing what's happening on the "top" side or even the interior of the cell. Our group has focused on engineered surfaces typically reserved for microelectronics as potential surfaces to control cell behavior. These devices allow the exploration of novel substrates including titanium, tungsten, and tantalum intermixed with silicon oxide. Furthermore, these devices allow the exploration of the intricate patterning of surface materials and surface geometries i.e., trenches. Here we present two important advancements in our research: (1) the ability to split a fixed cell through the nucleus using an inexpensive three-point bend micro-cleaving technique and image 3D nanometer scale cellular components using high-resolution scanning electron microscopy; and (2) the observation of nanometer projections from the underbelly of a cell as it sits on top of patterned trenches on our devices. This application of a 3-point cleaving technique to visualize the underbelly of the cell is allowing a new understanding of how cells descend into surface cavities and is providing a new insight on cell migration mechanisms.

Manipulating mammalian cell morphologies using chemical-mechanical polished integrated circuit chips.

Tungsten chemical-mechanical polished integrated circuits were used to study the alignment and immobilization of mammalian (Vero) cells. These devices consist of blanket silicon oxide thin films embedded with micro- and nano-meter scale tungsten metal line structures on the surface. The final surfaces are extremely flat and smooth across the entire substrate, with a roughness in the order of nanometers. Vero cells were deposited on the surface and allowed to adhere. Microscopy examinations revealed that cells have a strong preference to adhere to tungsten over silicon oxide surfaces with up to 99% of cells adhering to the tungsten portion of the surface. Cells self-aligned and elongated into long threads to maximize contact with isolated tungsten lines as thin as 180 nm. The orientation of the Vero cells showed sensitivity to the tungsten line geometric parameters, such as line width and spacing. Up to 93% of cells on 10 µm wide comb structures were aligned within ± 20° of the metal line axis. In contrast, only ~22% of cells incubated on 0.18 µm comb patterned tungsten lines were oriented within the same angular interval. This phenomenon is explained using a simple model describing cellular geometry as a function of pattern width and spacing, which showed that cells will rearrange their morphology to maximize their contact to the embedded tungsten. Finally, it was discovered that the materials could be reused after cleaning the surfaces, while maintaining cell alignment capability.

Incidence and characteristics of stroke during 90-day follow-up in patients stabilized after an acute coronary syndrome.

BACKGROUND: Stroke is a rare but serious event that complicates the course of patients with acute coronary syndromes (ACS). The type, outcome, and risk factors of stroke occurring in stabilized patients with ACS have not been previously reported. METHODS: We evaluated stroke incidence, subtypes, and outcomes, in addition to demographics and clinical risk characteristics associated with stroke among patients enrolled in the Sibrafiban versus Aspirin to Yield Maximum Protection from Ischemic Heart Events Post-acute Coronary Syndromes (SYMPHONY) and 2nd SYMPHONY trials. RESULTS: Of 15,904 stabilized patients with ACS, 113 (0.71%) had a stroke over a median follow-up of 90 days. The majority of strokes occurred within 30 days of presentation, and the time course for stroke occurrence paralleled that of myocardial (re)infarction. Most strokes were ischemic (78%), and 52% resulted in moderate or severe disability or death. Patients with stroke were older and more often had hypertension, diabetes, peripheral vascular disease, and atrial fibrillation. Among patients with stroke who had cardiac catheterization, percutaneous coronary intervention, or coronary artery bypass grafting, stroke occurred predominantly after the procedure. No difference in occurrence or type of stroke was observed in the assigned treatment groups. In multivariable modeling age, heart failure, prior stroke, left bundle branch block, and systolic blood pressure predicted the occurrence of stroke. CONCLUSIONS: In patients stabilized after presenting with a spectrum of ACS and treated with sibrafiban and/or aspirin, stroke occurred in fewer than 1% within 90 days but carried a significant mortality and morbidity risk.

Nonocclusion and spontaneous recanalization rates in acute ischemic stroke: a review of cerebral angiography studies.

BACKGROUND: Spontaneous recanalization is an understudied phenomenon in stroke. It is often overestimated by nonocclusion rates. The heterogeneity of the causes and manifestations of stroke and of the studies assessing vascular patency has created difficulties in assigning accurate rates of its incidence. METHODS: Systematic review of published articles about cerebral angiography in stroke. RESULTS: Lack of anticipated occlusions (nonocclusion rates) was noted in 28% of patients in suspected vessels 6 hours after stroke onset, whereas documented occlusions were noted in 17% of patients who underwent spontaneous lysis at 6 to 8 hours. At 3 to 4 days, the nonocclusion rate was 50% of studied vessels. CONCLUSIONS: In the first 6 to 8 hours from stroke onset, spontaneous recanalization occurs in approximately 17% of patients, whereas nonocclusion exists in about 28% of patients and up to 50% by 4 days after stroke.