There is an ongoing and increasing interest in the significant and essential role that food plays in the health and survival of all people. As masticatory efficiency diminishes drastically in edentulous patients, many researchers in the past two decades have been studying how dietary intake varies when different types of oral rehabilitation are provided. Since the use of implants to support prostheses in edentulous mandibles has been shown to significantly improve masticatory performance, the question remains as to whether this improvement will influence nutritional status. In the present study, we used several nutritional markers to compare the nutritional status of edentulous patients who randomly received either mandibular conventional dentures or implant-supported overdentures one year previously. Although the conventional denture wearers reported having more difficulty chewing hard foods, no significant differences were detected in any of the nutritional markers. Therefore, even though chewing is more difficult for the patients wearing conventional dentures, it appears that the nutritional status of these two groups is similar.

We examined the hypothesis that maturation ameloblasts degrade enamel matrix in a manner analogous to bone matrix degradation mediated by osteoclasts. Thus, we assessed the distribution of the cation-independent mannose 6-phosphate receptor (MRP) and lysosomal enzymes in the enamel organ and in the alveolar bone surrounding the rat incisor. The MPR was observed on the ruffled border of the ruffle-ended ameloblast (RA) but not on the distal call membrane of the smooth-ended ameloblast (SA), although both cells demonstrated strong immunoreactivity in the Golgi region. Immunogold localization of cathepsin B showed more labelling on the distal end of RA than SA, indicating that the source of the extracellular cathepsin B was likely the RA. Since MPR and lysosomal enzymes were also detected on the ruffled border of osteoclasts, our immunocytochemical approach provides strong evidence for a similarity between the maturation of enamel, as mediated by RAs, and bone matrix degradation by osteoclasts. / We also examined the nature of the basement membrane-like structure between maturation ameloblasts and the surface of enamel, and the possible role it may play in the maturation of enamel. We used high resolution electron microscopy combined with immunohistochemical localization of laminin, heparan sulfate proteoglycan (HSPG) and type IV collagen. Our results indicated that this structure was a highly specialized basement membrane unusually rich in HSPG. The cord network was replaced by a network of fine filaments, identified as core filaments of cords containing type IV collagen. A proposed role for this basement membrane is likely to be mediation of firm attachment of maturation ameloblasts to the surface of the enamel. / Since integrins play an essential role in cell-substratum interactions, we investigated the distribution of the integrin beta1 subunit on osteoclasts and ameloblasts. Immunocytochemistry showed significant concentrations of beta1 integrin at the ruffled border of osteoclasts, and negligible staining at the sealing zone. Since beta1 integrin localization was higher in the RA than the SA, we suggest that beta1 may have a role in the cell modulations. This role is likely to be recognition of extracellular matrix components and consequent interaction of RA with that matrix. The findings that the ruffled border of both RAs and osteoclasts display the most intense labelling for beta1 integrin, further supports our hypothesis that these cells are functionally similar.

<p>Chronic dental disease is acknowledged to be the most prevalent preventable chronic disease in children and is disproportionately higher for Hispanic children who are part of the nation's largest minority group (Crall &amp; Edelstein, 2001; Flores et al., 2002; Barker &amp; Horton, 2008). In spite of efforts to provide access to dental services, parents make the ultimate decision if and when to take their child to the dentist. Management of this chronic condition lessens pain, improves attendance at school, improves concentration, and improves grades (Dental Health Foundation, 2006; Percy, 2008). Successful management is dependent upon identifying the barriers Hispanic parents face in seeking dental care for their children. Culturally appropriate instruments are key in identifying barriers that parent's face to advance what is known about the oral health needs of Hispanic children (Ramos-Gomez et al., 2005). A convenience sample (N = 322) of primarily Hispanic parents and guardians (94.3%) were recruited from two clinics in Los Angeles which provide care to underserved communities in Southern California. The purpose of the first phase of the study was to determine the cultural equivalence of translated measures of oral health factors (i.e., oral health beliefs, parental dental anxiety, access to dental care, perceived discrimination, and pediatricians' role in seeking dental care) based on the Behavioral Model for Vulnerable Populations that were combined to develop <i>The Children's Oral Health Survey (COHS)</i> used in the second phase of the study. The purpose of the second phase was to determine the factors that influence utilization of oral health services in Hispanic children. Findings from this research found gender to be a significant predictor of dental care utilization for children. In comparison to parents who had one child, parents with more than one child were more likely to take at least one child for dental visits. More importantly, parents who thought their children were treated with respect by dental staff was significant in influencing utilization of oral health services. Findings from this research using the translated instruments suggested that Hispanic parents may not understand the questions and therefore demonstrates that a tool that is culturally developed would better identify the oral health issues of Hispanic parents. </p>

<p><b>Problem</b>: Fear of a painful dental injection and subsequent avoidance behavior are significant barriers to regular visits to the dentist. An anesthetic procedure that would avoid the discomfort of a local anesthetic injection thus obviating fear and anxiety about receiving a &ldquo;shot,&rdquo; would greatly benefit dental patients. </p><p> <b>Methods</b>: The study employed a multi-center, randomized, double-blind, placebo-controlled, parallel-groups design to assess the safety and efficacy of Kovacaine Mist delivered intranasally for inducing pulpal anesthesia of maxillary teeth sufficient to allow completion of the Study Dental Procedure. A total of 36 subjects, randomized 2:1 (Kovacaine Mist: Placebo) were enrolled. </p><p> <b>Results</b>: Kovacaine Mist was significantly superior to placebo (p&lt;0.0001) with respect to the proportion of subjects who did not require rescue by injection of local anesthetic to complete the Study Dental Procedure. </p><p> <b>Conclusions</b>: Based of the results of this clinical trial, a nasal anesthetic, such as kovacaine mist, could potentially be used as a safe and effective alternative to maxillary infiltration for anesthetizing maxillary premolars and anteriors to achieve pulpal anesthesia. </p>

<p> Study objectives were to determine the effectiveness, reproducibility, and repeatability of dental evaluation for estimating cattle age. Cattle (n = 400) aged 1.5 to 20 yr were evaluated by 3 technicians for estimated age via dentition. A subset (n = 383) was aged again 4 wk later by the same observers. Age estimations were most accurate in YOUNG (&le; 5 yr old) cattle with at least 95.7% rate of accuracy within 2 yr across all observers and observation events. For MIDDLE (6 to 10 yr old) and OLD (> 10 yr old) cattle, these accuracies were 81.5 and 62.1%, respectively. Reproducibility proved high, with all observers consistently assigning age estimates within 1 yr of one another for more than 9 out of 10 YOUNG animals; all observers agreed on at least every 8 out of 10 estimations for all age groups within 3 yr. Repeatability was less consistent.</p>

Enamel proteins are extracellular matrix proteins expressed throughout enamel formation. However, questions concerning their numbers and origins are still somewhat ambiguous. To characterize the nascent enamel proteins, cell free translation and immunoprecipitation procedures were performed using poly(A)$ sp{+}$RNA isolated from freeze-dried segments of rat incisor enamel organs at the secretory, early maturation, and mid maturation stages of amelogenesis. Phosphoimaging revealed that the enamel organ produces enamel proteins continuously throughout enamel development albeit in decreasing number and intensity. Ten enamel proteins were translated at the secretory stage and ranged in molecular weight from 80 to 18 kDa, resembling the number (Simmer et al., 1994) and the size (DenBesten et al., 1992) of RNA transcripts recently described for murine and rat. At the early and mid maturation stages, the enamel proteins span a 27 to 68 kDa region. This selected expression of enamel proteins at each stage of development suggests that specific proteins may be important for the maturation process.

Pterygomaxillary separation during Le Fort I osteotomy has been associated with life-threatening complications. Fractures of the pterygoid plates may play a role in the occurrence of these problems and may impede desired movements of the maxilla. This study compares the incidence of complications and pterygoid plate fractures during Le Fort I osteotomy with and without the use of a curved osteotome. Patients were randomly assigned to one of two groups in which pterygomaxillary separation was achieved either with or without osteotome. Measurements of lateral maxillary wall thickness, clinical assessment of the presence and location of fractures, and a subjective evaluation of the ease of downfracture were recorded. Coronal and axial CT scans were obtained between the seventh and tenth postoperative day. / There was no significant difference in incidence of pterygoid plate fracture between the two groups. A strong clinical trend was detected for males to have a greater incidence of pterygoid plate fractures than females. The incidence of palatine bone fractures was low. Low level fractures of the pterygoid plates of the sphenoid bone are a commonplace occurrence during the Le Fort I osteotomy. Further studies assessing alternative methods of pterygomaxillary separation are recommended.

Experimental investigations were carried out concerning the use of bovine bone (Unilab Surgibone) grafted in the tibiae of rats. The first experiment evaluated tissue response of bovine bone as an inlay graft and the second experiment as an onlay graft. Histological and morphometric analyses were performed in order to obtain baseline data on tissue response for future experiments using titanium implants with bovine bone grafts in this model. Light microscopy demonstrated rapid incorporation of the inlay graft by new bone, whereas, the onlay graft was mainly encapsulated by fibrous tissue. However, a residual increase in the thickness of the outer cortex of the tibiae was observed with onlay graft. From the results of this study it appeared that Unilab Surgibone was biocompatible and did not induce a foreign body reaction. Future investigations using titanium implants in combination with the bovine bone grafts appears to be possible especially if an inlay/onlay design is attempted.

Previous research has demonstrated that although women may find post-operative pain more intense than men, males are more disturbed than females by low levels of pain that last over time. In these studies, females had a tendency to rate the intensity of pain higher than males, but males had stronger affective responses following the surgical placement of intra-oral implants. However, these findings have not been investigated in an experimental setting. This experiment examined the pain responses of 20 healthy subjects (10 males, 10 females), who were subjected to capsaicin-induced pain on the face and ankle (on separate sessions). During the experiment, all subjects rated their pain intensity, unpleasantness, and anxiety on visual analog scales (VAS). In addition, throughout the experiment, heart rate was monitored every five minutes and mood was assessed once before and after the experiment. Finally, subjects also completed the McGill Pain Questionnaires (MPQ) once at the end of every session. Results revealed that although there were generally no statistically significant sex differences in the pain ratings during the experiment, there was a sex * time interaction with males displaying increasing anxiety scores over time with the capsaicin patch on the face while the anxiety scores of females decreased over time with the capsaicin patch on the face (F = 1.64, P = 0.02). Also, there was a tendency for the relative unpleasantness (unpleasantness/intensity ratio) to be greater for males than females over time on the face (F = 3.43, P = 0.08). Males and females did not differ in both the mean number of words chosen and the pain rating index of the MPQ for all categories. In addition, there were no sex differences for heart rate and mood for both the ankle and face regions throughout the experiment. Taken together, these results replicate previous findings that men may find low levels of pain more disturbing than women.

Craniofacial development is an intricate process, involving cranial neural crest (NC) and anterior facial tissue. NC migration is regulated by multiple mechanisms and activity of one or more organizer regions. Work presented here explores the role of the EAD, an organizer of craniofacial development in Xenopus, and its reciprocal signaling with cranial NC. The EAD later contributes to the mouth, nostrils, and anterior pituitary. EAD function involves the Kinin-Kallikrein pathway that was shown for the first time to be necessary for mouth formation. Facial transplants demonstrate that EAD-localized Kinin-Kallikrein function is required for migration of first arch cranial NC into the face. After migration, cranial NC signals back to the EAD to regulate mouth opening via the Wnt/PCP pathway. This pathway is associated with a process consistent with convergent extension of the EAD, whereby a wide and short epithelial mass narrows and lengthens, and cells and nuclei undergo stereotypical changes. The resultant EAD is a bilayered epithelium that later splits to form the mouth opening. Identification of the EAD as a NC organizer, reciprocal interaction of EAD and NC, and convergent extension associated with mouth formation has not previously been described during craniofacial development. Face formation is widely conserved, so findings in frog are likely relevant to amniotes and will provide insight into causes of craniofacial deformities. / Biological Sciences in Dental Medicine