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Taking occlusal photographs can be challenging; they are by far the most difficult images to obtain. Achieving an ideal photograph of every arch may not always be possible. In patients with limited range of motion of the mandible, an oversized or hyperactive tongue, an excessive gag reflex, or reduced flexibility of lips and checks, the goal of an ideal occlusal photograph may not be achieved. Nevertheless, patience, practice, and attention to detail can often provide a satisfactory result. 相似文献
54.
Kevin J. Donly DDS MS 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2005,17(6):380-380
The popularity of vital tooth whitening has increased significantly over the past two decades. Professionally supervised "in-office" and "at-home" tooth whitening methods have been documented in the literature with evidence of safety and effectiveness. Although the literature includes considerable information about vital tooth whitening in adults, minimal information is available concerning vital tooth whitening in children and adolescents.
The need to provide vital tooth whitening for children might be infrequent owing to the natural whiteness of children's teeth. However, there are circumstances when tooth whitening can be desirable for children, such as fluorosis discoloration, generalized tooth darkening, post-traumatic injury discoloration, and postorthodontic tooth discoloration.
Few well-controlled clinical trials evaluating the safety and effectiveness of vital tooth whitening in children are available in the literature, Furthermore, these published clinical trials were carried out by the same principal investigator. This review examines these trials and offers recommendations accordingly. 相似文献
The need to provide vital tooth whitening for children might be infrequent owing to the natural whiteness of children's teeth. However, there are circumstances when tooth whitening can be desirable for children, such as fluorosis discoloration, generalized tooth darkening, post-traumatic injury discoloration, and postorthodontic tooth discoloration.
Few well-controlled clinical trials evaluating the safety and effectiveness of vital tooth whitening in children are available in the literature, Furthermore, these published clinical trials were carried out by the same principal investigator. This review examines these trials and offers recommendations accordingly. 相似文献
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Jürgen Vogt Torsten Schwarz Daniel Gras Johannes Sperzel Philippe Ritter Willem de Voogt Jean-Pierre Cebron Martin Seifert Bruce Tockman Bernd Schubert Eric Johnson Annette Doelger Thierry Pochet Elisabeth Mouton Christian Butter 《Journal of interventional cardiac electrophysiology》2007,19(1):61-68
Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left
ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F
inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding
the need for catheter change.
Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant.
Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters
had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation
success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients
the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter.
Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation
success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for
sub-selecting the CS tributaries. 相似文献
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Anette M.C. Fransson DDS A
ke Tegelberg DDS PhD Anders Johansson DDS PhD Bengt Wenneberg DDS PhD 《American journal of orthodontics and dentofacial orthopedics》2004,126(6):687-693
The aim was to identify the incidence and types of possible adverse events in the masticatory system after treatment with a mandibular protruding device (MPD) during a 2-year period in patients with obstructive sleep apnea (OSA) or snoring. The subjects comprised 65 middle-aged patients (44 OSA patients, 21 snorers). A clinical examination and a questionnaire concerning signs and symptoms from the masticatory system were performed before, after 6 months, and after 2 years of MPD use. The frequencies of registered signs from the masticatory system, such as muscle and joint tenderness, palpation, and pain during mandibular movement, decreased significantly between baseline and the 2-year follow-up. There were significant changes in the mandibular range of protrusion (+0.7 mm, P < .001), overjet (-0.5 mm, P < .001), and overbite (-0.6 mm, P < .001) compared with the initial examination. Nine patients developed a lateral open bite during treatment, and 2 of them experienced subjective symptoms related to the altered occlusion but still used the MPD every night. No patient reported pain on opening the mouth wide or during jaw movements. Two reported tiredness on jaw function. The reported frequency of headaches was also significantly reduced (P < .01). The high compliance rate in MPD use showed that the therapy is well tolerated, but there is a risk of minor alterations in the occlusion during MPD treatment. 相似文献
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