Monitoring orthodontic tooth movement in rats after piezocision by bone scintigraphy.

AIM: Piezocision, corticocision of mineralized tissue by ultrasound showed promising results in accelerating tooth movement induced by orthodontic appliances although the biologic effects of this procedure are not well-understood so far. The aim of this study was to investigate the impact of piezocision on bone remodeling in rats by bone SPECT imaging. MATERIAL AND METHODS: Ten male Wistar rats underwent surgical placement of orthodontic appliances on each side of the maxilla followed by piezocision on one side only. Each rat underwent 99mTc-MDP bone SPECT/CT imaging before surgery (T0), and 2 (T1) and 4 weeks (T2) after surgery. Bone uptake is expressed as median [IQR] min-max in percentage of the injected activity per ml computed from the 10 voxels with the highest uptake (%IAmax10/ml). RESULTS: Pooled data regardless of the piezocision showed a significant increase in bone uptake from T0 (3.2 [2.8-3.9] 2.6-4.9) to T1 (4.4 [3.8-4.6] 3.4-4.8; p = 0.001). Thereafter, the uptake decreased to T2 (3.8 [3.1-4.4] 2.8-4.8; p = 0.116). No significant differences in bone uptake were found between the maxilla sides without and with piezocision: T1: without (4.3 [3.8-4.5] 3.4-4.8) vs. with (4.5 [3.7-4.6] 3.5-4.7; p=0.285), T2: without (4.0 [3.1-4.5] 2.8-4.8) vs. with (3.7 [3.0-4.4] 2.8-4.8; p=0.062). CONCLUSION: 99mTc-MDP bone SPECT imaging in rats was able to reproduce changes in bone uptake in the maxilla after placement of orthodontic appliances inducing measurable tooth movement. An additional effect of piezocision on bone remodeling in terms of bone uptake was not detectable which is probably due to the pronounced and significant effects induced by the orthodontic appliances per se, which may mask the potential effects of additional piezocision.

Impact of piezocision on orthodontic tooth movement.

OBJECTIVE: This study investigated the impact of a single piezocision in the maxillary alveolar process on the speed of tooth movement. The null hypothesis was that the speed of tooth movement will be equal with and without piezocision. METHODS: All maxillary molars on one side were moved against the combined incisors in 10 ten-week-old male Wistar rats. Under general anesthesia, a force of 25 cN was applied on either side using a Sentalloy closed coil spring. After placing the orthodontic appliance, vertical corticision was performed using a piezotome under local anesthesia, 2 mm mesial from the mesial root of the first molar on a randomly selected side; the other side served as the control. At the beginning of the treatment, and 2 and 4 weeks later, skull micro-computed tomography was performed. After image reconstruction, the distance between the mesial root of the first molar and the incisive canal, and the length of the mesial root of the first maxillary molar were measured. Moreover, the root resorption score was determined as described by Lu et al. RESULTS: Significantly higher speed of tooth movement was observed on the corticision side; thus, the null hypothesis was rejected. The loss of root length and root resorption score were significantly more pronounced after piezocision than before. A strong correlation was observed between the speed of tooth movement and root resorption on the surgical side, but the control side only showed a weak correlation. CONCLUSIONS: Piezocision accelerates orthodontic tooth movement and causes increased root resorption.

From A to Z(OOR): The Clinical Spectrum of Acute Zonal Occult Outer Retinopathy.

Acute idiopathic blind spot enlargement (AIBSE) is often caused by Acute Zonal Occult Outer Retinopathy (AZOOR), an outer retinal disease. We report two illustrative cases of AZOOR. The first one was a 21-year-old white female who presented with a scotoma and "shimmering lights" in her left eye. In the second case, a 73-year-old white female was referred for evaluation of a "bitemporal hemianopsia" that started years prior, with no clinical significant photopsias. To our knowledge, case two is the longest documented duration of bilateral, progressive, and chronic, idiopathic, enlargement of the blind spot (CIBSE) documented in the English language ophthalmic literature.

A comparison of different sealants preventing demineralization around brackets.

AIM: Aim of the study was to compare how six different sealants resisted thermal, mechanical, and chemical loading in vitro. MATERIALS AND METHODS: In all, 120 extracted human, nondecayed molars were divided into six groups (20 samples each) and embedded in resin blocks. The buccal surfaces of the tooth samples were polished and divided into three areas. Area A contained the product to be analyzed, area B was covered with colorless nail varnish (negative control), and area C remained untreated (positive control). The samples were stored in 0.1% thymol solution. To simulate a 3-month thermomechanical load, the samples were subjected to thermal cycling and a cleaning device. After 7 days incubation in a ten Cate demineralization solution (pH value: 4.6), the samples were dissected using a band saw and the lesion depths and demineralization areas were evaluated and compared microscopically. RESULTS: The tooth surfaces treated with PRO SEAL® showed no demineralization. Mean lesion depths of 108.1, 119.9, 154.9, 149.2, and 184.5 µm were found with Alpha-Glaze®, Seal&Protect®, Tiefenfluorid®, Protecto®, and Fluor Protector, respectively. There was a significant difference between PRO SEAL® and the other products (p > 0.0001). There was no significant difference between the other products. CONCLUSION: PRO SEAL® resisted thermal, mechanical, and chemical loading in vitro, providing protection against white spot lesions.

Use of A-scan Ultrasound and Optical Coherence Tomography to Differentiate Papilledema From Pseudopapilledema.

SIGNIFICANCE: Differentiating papilledema from pseudopapilledema reflecting tilted/crowded optic discs or disc drusen is critical but can be challenging. Our study suggests that spectral-domain optical coherence tomography (OCT) peripapillary retinal nerve fiber layer thickness and retrobulbar optic nerve sheath diameter (ONSD) measured by A-scan ultrasound provide useful information when differentiating the two conditions. PURPOSE: To evaluate the use of A-scan ultrasound and spectral-domain OCT retinal nerve fiber layer thickness (RNFLT) in differentiating papilledema associated with idiopathic intracranial hypertension from pseudopapilledema. METHODS: Retrospective cross-sectional analysis included 23 papilledema and 28 pseudopapilledema patients. Ultrasound-measured ONSD at primary gaze, percent change in ONSD at lateral gaze (30° test), and peripapillary RNFLT were analyzed. Receiver operating characteristic curves were constructed using one eye from each subject. RESULTS: Compared with pseudopapilledema, papilledema eyes showed larger mean ONSD (5.4 ± 0.6 vs. 4.0 ± 0.3 mm, P < .0001), greater change of ONSD at lateral gaze (22.4 ± 8.4% vs. 2.8 ± 4.8%, P < .0001), and thicker retinal nerve fiber layer (219.1 ± 104.6 vs. 102.4 ± 20.1 µm, P < .0001). Optic nerve sheath diameter and 30° test had the greatest area under the receiver operating characteristic curve, 0.98 and 0.97, respectively; followed by inferior quadrant (0.90) and average RNFLT (0.87). All papilledema eyes with Frisén scale greater than grade II were accurately diagnosed by ONSD, 30° test, or OCT. In mild papilledema (Frisén scale grades I and II, n = 15), area under the receiver operating characteristic curve remained high for ONSD (0.95) and 30° test (0.93) but decreased to 0.61 to 0.71 for RNFLT. At 95% specificity, sensitivities for ONSD, 30° test, and RNFLT were 91.3%, 91.3%, and 56.5%, respectively, for the entire papilledema group and 80.0%, 86.7%, and 13.3% for the mild papilledema subgroup. CONCLUSIONS: Retinal nerve fiber layer thickness can potentially be used to detect moderate to severe papilledema. A-scan may further assist differentiation of mild papilledema from pseudopapilledema.

Influence of piezotomy and osteoperforation of the alveolar process on the rate of orthodontic tooth movement: a systematic review.

OBJECTIVE: The minimally invasive procedures piezosurgical corticocision and osteoperforation have been advocated as methods to accelerate orthodontic tooth movement and to shorten treatment time, but without large-scale trauma of the periosteum and the bone. The aim of this study was to evaluate if there is evidence supporting these claims based on a systematic review of the literature. MATERIALS AND METHODS: A search of PubMed and Google Scholar with the combined search terms "piezo*" and "tooth movement" was performed until May 2016. In addition, the keywords "osteoperforation" and "piezopuncture" were searched in both databases. All scientific articles were considered and examined for suitability by two scientists. Disagreements resolved by consensus. The first inclusion criterion was studies with human species. Second inclusion criterion the surgical procedure had to be performed transmucosally and without the elevation of a mucoperiosteal flap. Case series were also considered. RESULTS: The Google Scholar search delivered 516, the PubMed search 60 references. A total of 36 human trials fulfilling the first inclusion criterion were identified. Among those, in only 13 publications was a transmucosal technique used (12 on piezosurgical corticocision and 1 on osteoperforation). Of the 13 articles, 9 represented case series and only 4 were clinical trials. In all four trials, an acceleration of the orthodontic treatment was reported. However, the extent of the acceleration was inconsistent and in one article it disappeared when assessing the overall orthodontic treatment. CONCLUSION: Evidence for an acceleration of tooth movement in conjunction with the minimally invasive methods piezosurgical corticocision and osteoperforation of the alveolar process in humans is low.

Diagnostic Ophthalmic Ultrasound for Radiologists.

Ophthalmic ultrasound is an invaluable tool that provides quick and noninvasive evaluation of the eye and the orbit. It not only allows the clinicians to view structures that may not be visible with routine ophthalmic equipment or neuroimaging techniques but also provides unique diagnostic information in various ophthalmic conditions. In this article, the basic principles of ophthalmic ultrasound and examination techniques are discussed. Its clinical application is illustrated through a variety of ocular pathologic abnormalities (eg, narrow angles, ciliary body tumor, detached retina, choroidal melanoma, and papilledema).

Effect of untreated and treated temporomandibular joint arthritis on mandibular volume development in growing rabbits.

OBJECTIVES: The goal of this work was to investigate the volume development of the mandible in growing rabbits with bilaterally induced temporomandibular joint (TMJ) arthritis that was either left untreated or treated with the tumor necrosis factor-alpha (TNF-α) antagonist etanercept. METHODS: A total of 18 New Zealand White rabbits aged 8 weeks were randomized to three groups of 6 animals each. Two of these groups were used as arthritis groups by sensitizing the 12 animals to ovalbumin (OA) at 10 weeks, followed by intraarticular OA injections to induce bilateral TMJ arthritis and repeating these injections every 3 weeks to maintain the inflammation. One of the two arthritis groups was treated by weekly subcutaneous etanercept injections, whereas the other group was left untreated. The remaining 6 animals served as controls. Maxillofacial CT scans were obtained at 3-week intervals (from week 10 of the rabbits' lives to the end of the experiment at 22 weeks) to volumetrically track the development of the mandibles after segmentation. RESULTS: The mandibles did not grow at a continuous rate, but the rate of development was found to decrease in all groups over the course of the study (weeks 10-22). The most extensive volume increases were noted during weeks 10-13. Severe growth deficiencies, especially of the condylar processes, were observed in the arthritis group not receiving treatment. The arthritis group treated with etanercept showed better rates of growth without, however, reaching the normal range of the control group. CONCLUSION: Antigen-induced TMJ arthritis was found to involve severe problems of growth similar to those in juvenile idiopathic arthritis. Etanercept can improve the volume development but does not reestablish an entirely normal rate of growth.

Effect of methotrexate upon antigen-induced arthritis of the rabbit temporomandibular joint.

BACKGROUND: Juvenile idiopathic arthritis (JIA) of the temporomandibular joint (TMJ) can cause severe growth disturbances of the craniomandibular system. Antigen-induced arthritis (AIA) of the rabbit TMJ is simulating the inflammatory process of the TMJ in JIA. The aim of this study was to investigate the effect of a systemic administration of methotrexate (MTX) on AIA in rabbits by means of three different histological staining methods. METHODS: After sensitization, a bilateral arthritis of the TMJ was induced by an intra-articular administration of ovalbumin in 12 New Zealand white rabbits aged 10 weeks. From the 13th week of age, six of the 12 rabbits received weekly intramuscular injections of MTX, and the other six animals remained without therapy. Another six animals served as controls, receiving no treatment or intra-articular injections at all. After euthanasia at the age of 22 weeks, all TMJs were retrieved en bloc. Sagittal sections were cut and stained with haematoxylin-eosin (H-E), Safranin-O for the evaluation of the Mankin score and tartrate-resistant acid phosphatase (TRAP). RESULTS: In the arthritis group, a chronic inflammation with degeneration of the articular cartilage was visible. In the MTX group, the signs of cartilage degeneration were significantly reduced compared with the arthritis group. In contrast, the joints in the control group were inconspicuous. A correlation between the Mankin score and TRAP-positive cells could be found. CONCLUSIONS: Systemic administration of MTX seems to have a positive effect upon the inflammatory process in the rabbit TMJ but fails to eliminate the sign of arthritis completely.

Effect of methotrexate on the mandibular development of arthritic rabbits.

INTRODUCTION: Juvenile idiopathic arthritis affecting the temporomandibular joint (TMJ) can cause severe disturbances of the mandibular development. Methotrexate (MTX) is often administered as a common used remission-inducing agent to treat this disease. The aim of this study was to investigate the effect of low dose MTX on the mandibular growth in arthritic rabbits. SUBJECTS AND METHODS: Eighteen 10-week-old female New Zealand white rabbits were randomly assigned to three groups with six animals in each group. After being sensitized to ovalbumin (OA), the first and the second group received intra-articular injections with OA. The first group remained untreated, the second was treated by weekly injections of MTX. Cephalograms were taken from each animal at 10, 13, 16, 19, and 22 weeks of age and six mandibular distances measured. RESULTS: All distances showed an increase between 10 and 20 per cent, whereas growth was more accentuated in the sagittal dimension. Significant differences in the overall growth could be observed between the arthritic and the control animals and less accentuated between the arthritic and the MTX animals. In contrast, existing differences between the groups were not significant during the intervals, but time had the greatest influence on mandibular growth. CONCLUSIONS: MTX seems to have a positive impact on growth in rabbits suffering from experimental arthritis of the TMJ.

Investigation of bone conditions for orthodontic anchorage plates in the anterior mandible.

OBJECTIVES: The clinical success of orthodontic anchorage plates depends on the stability of the miniscrews used for fixation. For good stability, the application site must provide bone of good quantity and quality. This study was performed to analyze bone quantity for orthodontic anchorage plates in the anterior mandible. PATIENTS AND METHODS: A total of 51 computed tomography (CT) scans of fully dentate patients (mean age 24.0±8.1 years; 27 men and 24 women) were evaluated. Measurements were taken to analyze the total orovestibular and vestibular cortical thickness of the mandibular jawbone at different anterior locations and levels. RESULTS: Vestibular cortical thickness is generally thinnest within the incisor area on the apex level. Its thickness increases in basal and distal directions. The total orovestibular thickness is also the least on the level of the anterior mandibular apices, becoming thicker toward more basal levels and the posterior teeth. CONCLUSION: We can reasonably assume that the stability of anchorage plates can be optimized by selecting a position well basal to the apices of the lower incisors, as this area offers enhanced cortical and total jawbone thickness.

Age and positional effect on the anterior chamber angle: assessment by ultrasound biomicroscopy.

Purpose. To investigate age- and position-related changes of anterior chamber angle anatomy in normal, healthy eyes. Patients and Methods. Thirty subjects were separated into a younger and older cohort. The superior and inferior anterior chamber angles of the eyes were measured in supine and sitting positions by ultrasound biomicroscopy (UBM) with bag/balloon technology. Statistical analysis was used to evaluate positional and age-related changes in angle morphology. Results. In the younger cohort, no location or positional differences in angle anatomy were observed. In the older cohort, the inferior quadrant was significantly narrower than the superior quadrant (P = 0.0186) in the supine position. This cohort also demonstrated an interaction effect between position and location. In the older cohort, the angle was deeper inferiorly while the subject was sitting but was deeper superiorly while the subject was supine. Conclusion. Comparison of positional variations in anterior chamber angle anatomy as measured by UBM has recently become possible. This study found that age-related positional changes in the anterior chamber angle anatomy exist in normal healthy eyes.

A comparison of two-way text versus conventional paging systems in an academic ophthalmology department.

Alphanumeric paging systems are unidirectional without prioritization capabilities. Newer electronic communication devices such as two-way text paging systems are capable of bidirectional paging and prioritization. While previous studies have evaluated alphanumeric paging systems in academic hospital settings, bidirectional two-way text paging systems have not been investigated. The goal of this study was to evaluate efficiency and impact on patient care delivery of a two-way text paging system compared to conventional one-way alphanumeric pagers. This unmasked, crossover prospective study was divided into three phases. In phase one, surveys were distributed to all ophthalmology attending physicians, residents, clinical technicians, and secretaries to assess the conventional alphanumeric paging system. In phase two, these participants used two-way text pagers without instruction (unstructured format) that they subsequently compared to the alphanumeric system with devised surveys assessing (on a scale of 0 to 100) time saved, increased daily efficiency, facilitation in patient care, and overall impression (helpfulness).In phase three, participants used a specific communication prioritization protocol (structured format) with the two-way text pagers with subsequent comparison and assessment with the same surveys. Compared to traditional alphanumeric pagers, new digital two-way text pagers were found to be statistically (p < 0.0001) more helpful by participants in all categories: as a time saver (80.33 vs. 56.95) p < 0.0001, increased daily efficiency (78.15 vs. 57.13) p < 0.0001, facilitation in patient care (78.79 vs. 56.95) p < 0.0001, and overall impression (helpfulness) (61.82 vs. 84.33) p < 0.0001. When compared to the alphanumeric pager, the two-way text pager was found to decrease subjectively call backs (73.6% to 45.6%, p < 0.0001), reduce interruptions of learning activities (43.63% to 26.6%, p < 0.0001) and enabled better patient care (59.8% to 42.2%, p < 0.0001). No significant statistical difference was found between the structured and unstructured system. Two-way text paging (structured versus unstructured guidance) was preferred over the conventional one-way alphanumeric paging system in every participant category. Two-way text paging is an effective alternative to alphanumeric paging, demonstrating saved time, increased daily efficiency, reduced call backs and interruptions of educational activities, and facilitation in patient care.

Effects of early maternal docosahexaenoic acid intake on neuropsychological status and visual acuity at five years of age of breast-fed term infants.

OBJECTIVE: We previously reported better psychomotor development at 30 months of age in infants whose mothers received a docosahexaenoic acid (DHA) (22:6n-3) supplement for the first 4 months of lactation. We now assess neuropsychological and visual function of the same children at 5 years of age. STUDY DESIGN: Breastfeeding women were assigned to receive identical capsules containing either a high-DHA algal oil (∼200 mg/d of DHA) or a vegetable oil (containing no DHA) from delivery until 4 months postpartum. Primary outcome variables at 5 years of age were measures of gross and fine motor function, perceptual/visual-motor function, attention, executive function, verbal skills, and visual function of the recipient children at 5 years of age. RESULTS: There were no differences in visual function as assessed by the Bailey-Lovie acuity chart, transient visual evoked potential or sweep visual evoked potential testing between children whose mothers received DHA versus placebo. Children whose mothers received DHA versus placebo performed significantly better on the Sustained Attention Subscale of the Leiter International Performance Scale (46.5 ± 8.9 vs 41.9 ± 9.3, P < .008) but there were no statistically significant differences between groups on other neuropsychological domains. CONCLUSIONS: Five-year-old children whose mothers received modest DHA supplementation versus placebo for the first 4 months of breastfeeding performed better on a test of sustained attention. This, along with the previously reported better performance of the children of DHA-supplemented mothers on a test of psychomotor development at 30 months of age, suggests that DHA intake during early infancy confers long-term benefits on specific aspects of neurodevelopment.

New technology for examining the anterior segment by ultrasonic biomicroscopy.

PURPOSE: To compare the comfort levels and measurement accuracy of the open-shell technique and a bag/balloon technology (ClearScan, ESI) in anterior segment ultrasound biomicroscopy. SETTING: Department of Ophthalmology and Visual Science, Robert Cizik Eye Clinic, University of Texas Medical School at Houston, Houston, Texas, USA. METHODS: In this prospective investigation, 20 subjects stated their preference and rated comfort (0 best to 5 worst) for the open-shell technique versus the bag/balloon technology. Three anterior chamber depth and sulcus-to-sulcus measurements were obtained, and the mean for each structure was taken as datum for each subject. Order presentation between the 2 methods was randomized. Pairwise t tests and linear regression analysis were used to determine statistical differences. RESULTS: One hundred percent of the cohort preferred the bag/balloon technology to the traditional open-shell technique. The mean comfort score was 0.40 +/- 0.53 (SD) and 2.95 +/- 0.90, respectively (P<.0001). Anterior chamber depth measurements did not differ clinically (0.056 mm) nor did sulcus-to-sulcus determinations (0.039 mm). CONCLUSION: Biometry, patient comfort, and ease of use were better with the ClearScan bag/balloon technology than with the traditional open-shell technique.

Remodeling along the bone-screw interface.

OBJECTIVE: The stability of cortical miniscrews depends on the contact between bone and implant. The aim of this study was to compare bone remodeling along the contact surface between the screw and bone with and without pre-drilling. MATERIALS AND METHODS: Twenty-four FAMI miniscrews (length 10 mm, diameter 2 mm) were inserted into the mandibular alveolar process apical to the premolars of four miniature pigs. Each pig received six screws, three on the one side with pre-drilling, three on the other side without pre-drilling. Polychrome fluorescent labels were used to assess the bone remodeling. After 12 weeks of osseointegration, all 24 screws and surrounding bone were removed. Microsections were prepared and analyzed histomorphometrically and under fluorescent microscopy. Differences between the groups were determined using the t test with a significance level of 5%. RESULTS: All the screws osseointegrated without any complications. Those without pre-drilling revealed a bone-screw contact of 64 +/- 11%, and those subjected to pre-drilling 63 +/- 12%. This difference was not significant. The mineral apposition rate, 1.6 +/- 0.4 microm/d and 1.7 +/- 0.4 microm/d, respectively, also failed to demonstrate any significant differences between the groups, while the portion of newly-formed bone in the pre-drilled group was significantly higher (59 +/- 9% vs. 27 +/- 6%). CONCLUSION: Significant differences in the bone-to-screw contact between the two groups are no longer in evidence after three months due to new bone formation. The minor extent of bone remodeling in the not pre-drilled group rules out substantial bone damage, which might have occurred during screw placement as a result of "cracks" or an excessive increase in pressure along the interface. The similar rate of new bone formation in both groups speaks against a stimulating effect of pre-drilling. Despite the absence of quantitative differences, it remains unclear whether the mechanical quality of the newly-formed bone resembles that of preexisting bone. Our findings seem to be applicable to the human mandible, however, its thinner cortical layer means less screw-to-bone contact is likely. We must reckon with less bone contact in the maxilla for the same reason.

Empirical advanced orthokeratology through corneal topography: the University of Houston clinical study.

PURPOSE: Traditionally, orthokeratology has used diagnostic lenses to determine the best fit. The purpose of this study was to determine the efficacy of fitting empirically from corneal topography, without the use of diagnostic lenses. METHODS: Twenty-nine subjects, 18 to 37 years old, with myopia of 1.00 to 4.00 diopters (D) and astigmatism of no more than 1.50 D, were entered into this 6-month study. Corneal topography, scanning slit topography and corneal thickness (Orbscan), confocal microscopy, ultrasound corneal thickness, aberrometry, and biomicroscopy were used to assess corneal changes. Unaided logMAR high-contrast visual acuity, subjective refraction, and questionnaires were used to monitor vision and symptoms. Follow-up visits were scheduled after 1 day, 1 week, 2 weeks, 1 month, 3 months, and 6 months. RESULTS: For 6-month data, unaided logMAR acuity improved from 0.78 +/- 0.26 in the right eye and 0.75 +/- 0.22 in the left eye to 0.06 +/- 0.18 in the right eye and 0.04 +/- 0.16 in the left eye. Myopia decreased from -2.55 +/- 0.87 D in the right eye and -2.47 +/- 0.89 D in the left eye to +0.45 +/- 0.74 D in the right eye and -0.17 +/- 0.69 D in the left eye. Shape factor, using corneal topography, increased from 0.85 +/- 0.13 in the right eye and 0.85 +/- 0.15 in the left eye to 1.28 +/- 0.32 in the right eye and 1.30 +/- 0.29 in the left eye. Both eyes showed a decrease in lower-order aberrations (i.e., defocus) and an increase in higher-order aberrations (i.e., spherical aberrations and coma). CONCLUSIONS: Myopia reduction after 1 week was clinically insignificant from the 1-month results, indicating that the full effect is achieved by 1 week. Neither total nor epithelial corneal thickness varied significantly from baseline measurements.