Análise da eficiência dos braquetes autoligáveis e convencionais na correção do apinhamento inferior / Efficiency of self-ligating and conventional brackets in the correction of mandibular crowding

Com o objetivo de avaliar a eficiência da correção do apinhamento mandibular, uma amostra de 20 pacientes, que não foram submetidos a extrações dentárias ou desgastes interproximais, foi dividida em dois grupos (I e II), onde no grupo I, 11 pacientes utilizaram braquetes autoligáveis da marca Easy Clip Aditek, e no grupo II, nove pacientes utilizaram braquetes convencionais marca Abzil Lancer prescrição Capellozza Padrão I. Para as medições do grau de apinhamento mandibular foi utilizado um paquímetro digital da marca Mitotoyo Digimatic Caliper. O grau de apinhamento mandibular anterior e posterior foi mensurado ao início e após seis meses de tratamento. Teste t Student foi utilizado para analisar a diferença do alinhamento anteroinferior entre os grupos. Após seis meses de tratamento, não houve diferença estatisticamente significante entre os grupos autoligável e convencional com relação a eficiência no alinhamento inferior, confirmando-se que em pacientes que não são submetidos a extrações dentárias, a eficiência no alinhamento mandibular independe do tipo de braquete.

To evaluate the efficiency of mandibular arch alignment with a self-ligating bracket system and a conventional bracket system in nonextraction patients, a sample of 20 consecutive patients who satisfied the inclusion criteria were enrolled and dividedinto two groups (I and II), where in the Group I, 11 patients using self ligating brackets brandEasy Clip Aditek, andin the Group II, nine patients with conventional brackets Abzil Lancer Capellozza prescription. For measurements of lower crowding degree, it was used a digital caliper brand Mitotoyo Digimatic Caliper to analyze the irregularity index of the mandibular arch. The mandibular arch's irregularity was remeasured six months later and T student test was used to analyze the difference in the anterior alignment of the groups. The efficiency of alignment in the mandibular arch in nonextraction patients is independent of bracket type, conventional or self-ligating.

Effect of topical anesthetic use on initial patient satisfaction and overall success with rigid gas permeable contact lenses.

BACKGROUND: Rigid gas permeable (RGP) contact lenses have numerous benefits; however, RGP lens use is not increasing in the United States. An important factor for this trend has been initial comfort. Studies have demonstrated that how RGPs are presented to patients, in addition to lens design, can play an important role in the initial comfort process. Another important factor could be the use of a topical anesthetic during the fitting and dispensing visits. The purpose of this study was to use a multicenter format to determine if topical anesthetic use increased the likelihood of patient satisfaction and success. METHODS: A total of 80 subjects, with no previous rigid lens wear experience, was entered into this 1-month study, including 20 subjects from each of 4 institutions. Subjects were randomly divided into the following two groups: (A) anesthetic or (B) placebo, with the former group receiving one drop of a topical anesthetic before lens insertion at both the diagnostic fitting and dispensing visits, whereas the latter group received a placebo. Subjects completed a questionnaire on their perception of rigid lens wear both immediately before fitting and at the 1-month visit. After diagnostic fitting with rigid lenses, subjects completed an adaptation questionnaire after 15 min, 1 week, 2 weeks, and 1 month of lens wear. RESULTS: Seventy of the 80 subjects completed the study and, of the 10 subjects who discontinued, 8 were in the placebo group. In all categories evaluated, the anesthetic group experienced a more optimum adaptation experience at each visit vs. the placebo group. Specifically, overall comfort was rated significantly higher at both dispensing and 2 weeks. In addition, the anesthetic group exhibited significantly greater overall satisfaction with rigid lens wear at 2 and 4 weeks. Also, the anesthetic group perceived their adaptation, sensitivity, and adaptation time to be significantly better at the 1-month visit. There was no significant difference in corneal staining between these two groups at each visit, with the exception of a greater amount of staining in the central quadrant for the placebo group at the 1-month visit. CONCLUSIONS: The use of a topical anesthetic at the fitting and dispensing visits for first-time wearers of RGP lenses resulted in significantly fewer dropouts, improved initial comfort, an enhanced perception of the adaptation process, and greater overall satisfaction after 1 month of lens wear as compared to the use of a nonanesthetizing placebo at those visits. This result, in combination with both presenting RGP lenses in a nonthreatening manner and optimizing the lens design and fitting relationship, should result in a positive adaptation process and successful wear of RGP contact lenses.

Effect of patient personality profile and verbal presentation on successful rigid contact lens adaptation, satisfaction and compliance.

BACKGROUND: Rigid gas permeable (RGP) lenses have numerous benefits, including quality of vision, ocular health, and reduction of myopic progression in young people. Nevertheless, RGP lens use is not increasing in the United States. It is possible that certain patient personality characteristics and/or how a practitioner presents RGP lenses to a new patient may affect satisfaction and success. The purpose of this study was to evaluate the effect of individual patient's personality and the practitioner's method of presenting RGP lenses to new patients on their ability to adapt to these lenses. METHODS: Forty-nine subjects, all noncontact lens wearers, were entered into this 1-month study, which was conducted at both the University of Missouri-St. Louis School of Optometry and the Pacific University College of Optometry. All subjects initially completed standardized questionnaires pertaining to locus of control, openness to new experiences, and motivation/expectations. After diagnostic fitting with a RGP lens material, the subjects were placed into one of the following three groups: (1) Fear-Arousing Non-Enthused; (2) Neutral Content Non-Enthused; or (3) Neutral Content Enthused. They observed one of three video presentations on RGP lens wear. Subjects submitted daily questionnaires providing their evaluation of such factors as comfort, wearing time, and handling. RESULTS: The results showed that there was a significant difference (chi(2) = 6.99; p < 0.05) among the different groups in the number of dropouts: 6/19 with the Fear-Arousing Non-Enthused group, 2/17 with the Neutral Content Non-Enthused group, and 0/13 with the Neutral Content Enthused group. There was also a significant difference (ANOVA F = 4.1, p < 0.05) among the groups on compliance, with the Neutral Content Enthused group demonstrating greater compliance. In terms of satisfaction, there was no significant difference among presentation groups. CONCLUSION: It was concluded that the method of presentation is important for successful RGP contact lens wear. If presented with genuine interest and a positive and realistic attitude, patients are more likely to succeed in RGP lens wear during the initial critical period.

The phenol red thread tear test: a cross-cultural study.

PURPOSE: To examine the results of the phenol red thread tear test in a cross-cultural comparison. METHODS: Two groups of 500 controlled normal subjects who do not wear contact lenses from the United States and Japan were investigated. RESULTS: The mean wet length of the thread for the United States was 23.9 mm (SD 9.5 mm). The mean for Japan was 18.8 mm (SD 8.6 mm). There was a significant difference between the two countries (P < 0.05). Males subjects had significantly longer wet lengths than females for both countries (P < 0.05). There was a moderate correlation between right and left eye results for both countries. CONCLUSIONS: The phenol red thread tear test was found to be easy to administer. Results were in line with current knowledge and theories of the lacrimal system. Results also indicated that this test may disclose subtle differences not previously found with other tear tests.

Initial comfort and surface wettability: a comparison between different contact lens materials.

A clinical investigation was performed to compare the initial comfort and surface wettability of the Novalens (Ocu-Tec), ENVISION (Polymer Technology Corporation) and D3X4 (Wesley-Jessen). Fifteen subjects were randomly fit with each one of these three lens materials. Initial comfort was significantly better with the D3X4 lens; no significant difference was found between the two rigid lens materials. No significant difference in lens surface wettability was found between the three materials.

The effect of contact lens cleaners on lens parameters and surface quality of the Novalens.

The purpose of this study is to evaluate the effect of one abrasive cleaner, one non-abrasive cleaner and one non-abrasive alcohol-based cleaner on the lens parameter stability of the NOVALENS. Twenty-four lenses, all NOVALENS material of identical design, were cleaned 100 times each. Eight lenses were cleaned with MiraFlow (CIBA Vision), eight lenses with Optic-Free Daily Cleaner and eight lenses with the Gas Permeable Daily Cleaner (PBH). The base curve radius, center thickness and power were verified immediately before, immediately after and (per manufacturer's recommendation) 4 hours after cleaning at baseline, 25, 50, 75 and 100 cleanings. Lens toricity of approximately 0.50D was found with all three cleaners after 100 cleanings. No change in lens power or center thickness was found. It was concluded that extreme care must be taken in handling the NOVALENS due to the potential of induced warpage.

Synergistic action of the benzene metabolite hydroquinone on myelopoietic stimulating activity of granulocyte/macrophage colony-stimulating factor in vitro.

The effects of in vitro pretreatment with benzene metabolites on colony-forming response of murine bone marrow cells stimulated with recombinant granulocyte/macrophage colony-stimulating factor (rGM-CSF) were examined. Pretreatment with hydroquinone (HQ) at concentrations ranging from picomolar to micromolar for 30 min resulted in a 1.5- to 4.6-fold enhancement in colonies formed in response to rGM-CSF that was due to an increase in granulocyte/macrophage colonies. The synergism equaled or exceeded that reported for the effects of interleukin 1, interleukin 3, or interleukin 6 with GM-CSF. Optimal enhancement was obtained with 1 microM HQ and was largely independent of the concentration of rGM-CSF. Pretreatment with other authentic benzene metabolites, phenol and catechol, and the putative metabolite trans, trans-muconaldehyde did not enhance growth factor response. Coadministration of phenol and HQ did not enhance the maximal rGM-CSF response obtained with HQ alone but shifted the optimal concentration to 100 pM. Synergism between HQ and rGM-CSF was observed with nonadherent bone marrow cells and lineage-depleted bone marrow cells, suggesting an intrinsic effect on recruitment of myeloid progenitor cells not normally responsive to rGM-CSF. Alterations in differentiation in a myeloid progenitor cell population may be of relevance in the pathogenesis of acute myelogenous leukemia secondary to drug or chemical exposure.

Clinical evaluation of fitting presbyopic patients with contact lenses.

This clinical investigation was performed to determine the success of using a system designed as a flow chart to fit presbyopic patients with contact lenses. The value of this type of system is to provide practitioners with a simple step-by-step approach to fitting presbyopic patients and reducing the costs of several trial fitting sets. Patients were fit with monovision, simultaneous vision bifocal, alternating vision bifocal or diffractive bifocal contact lenses. The patients were fit first with monovision, and, if unsuccessful with this or any of the above lens designs, they proceeded to the next stage. Stage 2 used the simultaneous lens design, Stage 3 the alternating lens design and Stage 4 the diffractive lens design. Of the 22 patients enrolled in the study, 17 (77.3 percent) were successful through Stage 3 and 18 (81.8 percent) were successful through Stage 4. The first three stages are those proposed by Bausch & Lomb as the Presbyopic Fitting System. The Presbyopic Fitting System was found to be simple to follow and successful in fitting presbyopic patients.

The effect of rigid gas permeable lens cleaners on lens parameter stability.

The introduction of fluoro-silicone/acrylate rigid lens materials has provided wearers with benefits that include, among others, enhanced surface wettability. However, several reports have associated these lens materials with lens power, base curve radius and center thickness changes over time, especially with long-term use of an abrasive cleaner. The purpose of this study was to evaluate the effect of abrasive and non-abrasive cleaners on these specific lens parameters. Twenty-four fluoro-silicone/acrylate lenses, 12 low minus and 12 high minus in power, were cleaned a total of 200 times each. Each lens was cleaned with one of-three different cleaners (1 non-abrasive and 2 abrasive) using one of two cleaning methods; palm of the hand or between the fingers (digital). Lens power was changed on 14/24 lenses (58.3 percent); the primary changes occurred with use of one of the abrasive cleaners. In addition, a slight reduction in center thickness was observed after abrasive cleaner use. Warpage occurred at a much higher rate with the digital cleaning method and with the use of an abrasive cleaner. It was concluded that practitioners should routinely reverify rigid lens power, center thickness and base curve radius; patients should be educated to carefully handle their lenses, notably cleaning them in the palm of the hand.

The effect of modification procedures on rigid gas permeable contact lenses: the UM-St. Louis Study.

The purpose of this study is to evaluate the effect of frequently performed modification procedures on quality of vision, surface wettability, optical quality and subjective response. One subject was optimally fitted with both silicone/acrylate (S/A) and fluoro-silicone/acrylate (F-S/A) lens materials of identical design. Two methods of surface polishing, edge polishing and repowering were used in addition to three different spindle speeds. Each pair of lenses was worn by the subject for a period of 4 hours and the subjective response was then compared to the baseline or premodification data. In addition, both low magnification photography and Scanning Electron Microscopy (S.E.M.) were performed on each lens. The results showed that the addition of 0.50D minus power reduced visual acuity, contrast sensitivity function and optical quality with one of the methods used. Front surface polish and edge polish procedures did not appear to affect short-term performance. Controlling polish, application and tool pressure on certain procedures resulted in similar findings. Further studies would be beneficial to evaluate the effect of longer wearing periods and the use of other modification procedures. The authors conclude that S/A and F-S/A lens materials can be successfully modified in-office with adherence to recommended guidelines.

Clinical investigation of the Paraperm EW rigid gas-permeable contact lens.

Paraperm EW is a high oxygen flux silicone/acrylate rigid lens material currently under clinical investigation for extended wear. The purpose of this paper is to report the clinical findings after 12 months of a 2-year investigation of 18 patients fitted with this material. Fifteen were successfully wearing Paraperm EW lenses at 1 year. The only significant clinical finding was keratometric flattening at the 1-month visit. It was concluded that the Paraperm EW lens was durable, comfortable, and provided excellent visual acuity during the course of this investigation without inducing any of the ocular complications sometimes associated with extended wear of hydrogel lenses.

Evaluation of endothelial integrity in extended wear.

The purpose of this investigation was two-fold: 1) to evaluate and compare the endothelium of hydrogel and rigid extended wear contact lens patients and 2) to evaluate a new technique for in-office endothelial photography. Endothelial photography was performed on seven patients who had worn low water content ultrathin soft lenses and seven patients who had worn rigid extended wear lenses for 1 year. In addition, seven non-lens wearers were used as a control group. Endothelial polymegathism and pleomorphic changes were evaluated via photographic observation using a new endothelial photography technique developed by G. Michael Murphy, O.D. The results showed that this was a viable method of endothelial photography for monitoring extended wear contact lens patients.