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Objective: Self-assessment of teeth shade was compared with professional assessment. Method and Materials: Patients' anterior teeth shade evaluation was conducted first by the patient (n = 193) and then by the clinician using the Vita shade guide. Results: In 18.7% of participants, self-assessment of teeth shade matched in hue and chroma to the clinician's evaluation. A positive correlation was found between participants' self-assessment of their shade and the clinician's assessment (P = .014; Pearson product moment correlation). Participants assessed their shade darker than the clinician (P <.001; chi-square test). Only 3.6% were highly satisfied with the shade of their teeth, and 83.4% were interested in a future bleaching procedure. Tooth shade was more accurately assessed by women (P = .02) and nonsmokers (P = .03; chi-square test). Conclusion: A patient's preference toward a lighter shade should be addressed during treatment planning to match the patient's expectations for esthetics and increase patient satisfaction of treatment outcome. Patients may prefer white and shiny rather than a natural appearance. [ABSTRACT FROM AUTHOR]

Objective: To elucidate the 3D interactions in the tooth-PDL-bone complex immediately after application of orthodontic forces and their implications on tooth movement and function., Methods: A special visualization method using microCT allows us to directly image in 3D the movements of a multirooted molar tooth inside the alveolar bone as well as the collagenous network of the PDL. Using fresh, unstained rat mandibular 1st molar under mesial loads of 0.5-1 N, we address basic concepts in orthodontics during the initial stages of orthodontic movement., Results: We show that immediately after the application of orthodontic load, direct distinct contacts between the tooth and the bone form in the furcation area. These contacts limit tooth movement and interfere with whole body translation. Only localized sites of highly compressed PDL between the root surfaces and the bone were observed. In general, the collagenous network of the PDL appeared loose and not densely packed in the compressed side. On the tension side, the fibers maintained their overall orientation without any significant extension of the fibers., Conclusions: Localized direct contact areas between the tooth roots and the bone at the furcation already form within a few minutes of orthodontic tooth movement. This direct and localized bone involvement guides the movement trajectory and provides a mechanism for the miscorrelation found between force levels and tooth movement during the initial stages of an orthodontic tooth movement., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The 3D imaging of soft tissues in their native state is challenging, especially when high resolution is required. An X-ray-based microCT is, to date, the best choice for high resolution 3D imaging of soft tissues. However, since X-ray attenuation of soft tissues is very low, contrasting enhancement using different staining materials is needed. The staining procedure, which also usually involves tissue fixation, causes unwanted and to some extent unknown tissue alterations. Here, we demonstrate that a method that enables 3D imaging of soft tissues without fixing and staining using an X-ray-based bench-top microCT can be applied to a variety of different tissues. With the sample mounted in a custom-made loading device inside a humidity chamber, we obtained soft tissue contrast and generated 3D images of fresh, soft tissues with a resolution of 1 micron voxel size. We identified three critical conditions which make it possible to image soft tissues: humidified environment, mechanical stabilization of the sample and phase enhancement. We demonstrate the capability of the technique using different specimens: an intervertebral disc, the non-mineralized growth plate, stingray tessellated radials (calcified cartilage) and the collagenous network of the periodontal ligament. Since the scanned specimen is fresh an interesting advantage of this technique is the ability to scan a specimen under load and track the changes of the different structures. This method offers a unique opportunity for obtaining valuable insights into 3D structure-function relationships of soft tissues.

The periodontal ligament (PDL), a soft tissue connecting the tooth and the bone, is essential for tooth movement, bone remodeling and force dissipation. A collagenous network that connects the tooth root surface to the alveolar jaw bone is one of the major components of the PDL. The organization of the collagenous component and how it changes under load is still poorly understood. Here using a state-of-the-art custom-made loading apparatus and a humidified environment inside a microCT, we visualize the PDL collagenous network of a fresh rat molar in 3D at 1 μm voxel size without any fixation or contrasting agents. We demonstrate that the PDL collagen network is organized in sheets. The spaces between sheets vary thus creating dense and sparse networks. Upon vertical loading, the sheets in both networks are stretched into well aligned arrays. The sparse network is located mainly in areas which undergo compressive loading as the tooth moves towards the bone, whereas the dense network functions mostly in tension as the tooth moves further from the bone. This new visualization method can be used to study other non-mineralized or partially mineralized tissues, and in particular those that are subjected to mechanical loads. The method will also be valuable for characterizing diseased tissues, as well as better understanding the phenotypic expressions of genetic mutants., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The components of the tooth-periodontal ligament (PDL)-alveolar bone complex act in a synergistic manner to dissipate the loads incurred during mastication. The complex incorporates a diverse array of structural features for this purpose. These include the non-mineralized and hence soft PDL that absorbs much of the initial loads. The internal structure of the tooth also includes soft interphases that essentially surround the dentine core. These interphases, although stiffer than the PDL, still are more compliant than the dentine core, and are thus key components that allow the tooth itself to deform and hence help dissipate the compressive loads. There is also direct evidence that even under moderate compressive loads, when the tooth moves in the alveolar bone socket, this movement is guided by specific locations where the tooth comes into contact with the bone surface. The combination of all these responses to load is that each tooth type appears to move and deform in a specific manner when loaded. Much, however, still remains to be learned about these three-dimensional responses to load and the factors that control them. Such an understanding will have major implications for dentistry, that include a better understanding of phenomena such as abfraction, the manner in which tooth implants function even in the absence of a PDL-like tissue and the implications to bone remodelling of the movements imposed during orthodontic interventions., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Deproteinized bovine bone mineral (DBBM) and human freeze-dried bone allograft (FDBA) were compared in five patients undergoing bilateral maxillary sinus floor augmentation using DBBM on one side and FDBA on the contralateral side. After 9 months, core biopsy specimens were harvested. Mean newly formed bone values were 31.8% and 27.2% at FDBA and DBBM sites, respectively (P = .451); mean residual graft particle values were 21.5% and 24.2%, respectively (P = .619); and mean connective tissue values were 46.7% and 48.6%, respectively (P = .566). Within the limits of the present study, it is suggested that both graft materials are equally suitable for sinus augmentation.

Teeth sustain high loads over a lifetime and yet intact tooth failure is rare. The different structures of the tooth, jaw bone and the intervening soft periodontal ligament enable the tooth to endure repeated loading during mastication. Although mechanical and functional properties of the different components are thoroughly investigated, the manner in which the whole tooth functions under load is still enigmatic. A custom-made loading system inside a microCT scanner was used to directly visualize the root movements in relation to the jaw bone as the rat molar tooth was loaded. At low loads no contact was observed between the root surface and the bone, whereas at higher loads three specific contact areas between the root surface and the jaw bone were observed. These contact areas restrict tooth movement in the buccal-lingual direction, but enable the tooth to rock in a "seesaw" like manner in the distal-mesial direction. The contact areas appear to play a role in determining tooth motion and in turn define the manner in which the whole tooth moves when loaded. These observations are important for understanding basic structure-function relations of the tooth-PDL-bone system, and have direct implications for better understanding pathological and therapeutic processes in orthodontics, periodontics and jaw bone regeneration., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Aims: To fabricate a friction-reducing coating onto different nickel-titanium (NiTi) substrates using inorganic fullerene-like tungsten disulfide (IF-WS(2)) nanoparticles and to estimate in vitro friction reducing extent of the coating., Materials & Methods: Different NiTi substrates were coated with cobalt and IF-WS(2) nanoparticles film by the electrodeposition procedure. Coating composition analyses was made by scanning-electron microscopy, energy dispersive x-ray spectroscopy, x-ray powder diffractometry and x-ray photoelectron spectroscopy. Friction evaluation was carried out using standard tribological tests and an Instron system., Results: Stable and well-adhered cobalt + IF-WS(2) coating of the NiTi substrates was obtained. Friction tests presented up to 66% reduction of the friction coefficient., Conclusion: NiTi alloy is widely used for many medical appliances; hence, this unique friction-reducing coating could be implemented to provide better manipulation and lower piercing rates.

Background: The use of postorthodontic fixed retainers made of wire and composite resin bonded to the lingual/palatal tooth aspect is a common practice that can affect gingival health. The purpose of this study was to evaluate the association of orthodontic treatment and fixed retainers with gingival health., Methods: The study included 92 consecutive subjects who arrived for routine dental examination at a military dental clinic between May and August 2007. Plaque and gingival indices, gingival recession, probing depth, and bleeding on probing were measured at the anterior sextants. When a fixed retainer was present, the distance was measured between the retainer and incisal edge and to the cemento-enamel junction. Past orthodontic treatment and smoking habits were self-reported. Postorthodontic patients were sorted by the presence or absence of fixed retainers., Results: The mean probing depth was 1.90 +/- 0.2 mm, and gingival recession was 0.06 +/- 0.02 mm; 20.8% of all sites exhibited bleeding on probing. Current smoking was reported by 20 (21.7%) patients. Labial gingival recession was significantly greater in treated (0.13 +/- 0.2 mm) patients compared to non-treated patients (0.05 +/- 0.2 mm; P = 0.03). Localized lingual gingival recession was significantly greater in teeth with fixed retainers (0.09 +/- 0.2 mm) compared to teeth with no fixed retainers (0.01 +/- 0.1 mm; P = 0.0002), as were plaque and gingival indices and bleeding on probing. Plaque on the lingual/palatal aspect showed a weak, positive correlation with lingual gingival recession (r = 0.16; P = 0.033)., Conclusion: Orthodontic treatment and fixed retainers were associated with an increased incidence of gingival recession, increased plaque retention, and increased bleeding on probing; however, the magnitude of the difference in recession was of low clinical significance.

Background: Esthetics has become an important issue in modern society, as it seems to define one's character. In the past, functional demands were the main consideration in dental treatment. Today, with the decrease in caries prevalence, the focus has shifted toward dental esthetics. The authors conducted a study to evaluate the factors influencing patients' satisfaction with their dental appearance and with the results of esthetic treatment., Methods: The authors surveyed a population of 407 adults (mean age, 21 years). They distributed a questionnaire regarding satisfaction with current dental esthetics and previous esthetic treatments., Results: Of the 407 subjects, 152 (37.3 percent) were dissatisfied with their dental appearance. Tooth color was the primary reason for dissatisfaction (133 [89.3 percent] of 149 subjects), followed by poor tooth alignment (36 [23.7 percent] of 152 subjects), although 110 (27 percent) of the 407 subjects had received orthodontic treatment. The authors found no correlation between patients' satisfaction with their dental appearance and having undergone any procedure to whiten their teeth. Nevertheless, 134 (88.2 percent) of the dissatisfied subjects reported that they would like to undergo this procedure., Conclusions: Tooth color was a major factor with regard to dental esthetics. Most subjects were interested in improving their appearance and whitening their teeth., Clinical Implications: When planning treatment, dentists should take into consideration esthetic objectives in addition to function, structure and biology. This requires the clinician to rely on several disciplines in dentistry to deliver the highest level of dental care, which should lead to a higher level of patient satisfaction.