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At least 199 records · Page 11Linked to original sources
PubMed2006

Assessment of dental arch relationships in Japanese patients with unilateral cleft lip and palate.

OBJECTIVE: Evaluation of the dental arch relationships of Japanese patients with unilateral cleft lip and palate (UCLP) from the orthodontic clinic of the University of Tokyo Hospital (UTH) compared with patients treated by the Oslo Cleft Team, Norway. DESIGN: Retrospective study and comparison with previous reports. MATERIALS: Dental models of 24 patients with UCLP in UTH taken before orthodontic treatment and before alveolar bone grafting were included. Surgeons in many hospitals performed primary surgeries. These models were matched for age and gender with 24 models from a consecutive series of patients treated by the Oslo Cleft Team as part of the Eurocran Good Practice Archive. A total of 48 models were evaluated. MAIN OUTCOME MEASURE: Dental arch relationship was rated with the Goslon Yardstick. The strength of agreement of rating was assessed with weighted kappa statistics. RESULTS: Intra- and interexaminer agreements evaluated by weighted kappa statistics were high, indicating good reproducibility. Almost 60% of the patients in UTH were classified into poor or very poor categories, and the mean Goslon score was 3.50. These results show a contrast to those in Oslo and were the poorest in comparison with previous reports. CONCLUSION: Dental arch relationships in patients with UCLP in UTH were poor. This seemed to be attributable to surgical procedures, but a factor of racial difference in the craniofacial morphology was also considered. Further intercenter research is required to clarify this point.

Alveoloplasty↗
PubMed2004

In vitro modeling of dental water line contamination and decontamination.

The contamination of dental unit water lines (DUWL) is an emerging concern in dentistry. The aim of this study was to use an in vitro DUWL to model microbial contamination and evaluate the decontamination efficacy of tetraacetylethylenediamine (TAED) solutions. A DUWL biofilm model used to simulate clinical conditions was used to generate a range of biofilms in DUWL. Three distinct biofilms were generated: (1) biofilm from water, (2) biofilm from a mix of water + contaminating human commensal bacteria, (3) biofilm from water with contaminating oral bacteria added after biofilm formed. The contaminating oral species used were Streptococcus oralis, Enterococcus faecalis and Staphylococcus aureus. Decontamination by simple water flushing or flushing with TAED was evaluated (2, 5 and 10 min intervals). The DUWL tubes were split and samples were plated onto a range of media, incubated and bacteria enumerated. Water flushing did not reduce the number of microorganisms detected. Bacteria were not detected from any of the TAED sampling points for any of the biofilm types tested. Interestingly, if contamination was introduced to new DUWL along with the waterborne species a biofilm was formed containing only the waterborne species. If however, an existing biofilm was present before the introduction of "contaminating" bacteria then these could be detected in the biofilm. This implies that if the DUWL are new or satisfactorily cleaned on a regular basis then the associated cross-contamination aspects are reduced. In conclusion, TAED provides effective control for DUWL biofilms.

Biofilms↗
PubMed1998

A new causal model of dental diseases associated with endocarditis.

Infective endocarditis (IE) is a serious disease that is associated with dental diseases and treatment. The objective of this study was to summarize the epidemiological information about IE and reevaluate previous causal models in light of this evidence. The world biomedical literature was searched from 1930 to 1996 for descriptive and analytic epidemiological studies of IE. Multiple searching strategies were performed on 9 databases, including MEDLINE, CATLINE, and WORLDCAT. Results show that: 1) the incidence of IE varies between 0.70 to 6.8 per 100,000 person-years: 2) the incidence of IE increases 20 fold with advancing age: 3) over 50% of all IE cases are not associated with either an obvious procedural or infectious event 3 months prior to developing symptoms; 4) about 8% of all IE cases are associated with periodontal or dental disease without a dental procedure: 5) the time from the diagnosis of heart valve deformities to the development of IE approaches 20 years: 6) the median time from identifiable procedures to the onset of IE symptoms is about 2 to 4 weeks: 7) the risk of IE after a dental procedure is probably in the range of 1 per 3,000 to 5,000 procedures: and 8) over 80% of all IE cases are acquired in the community, and the bacteria are part of the host's endogenous flora. The synthesis of these data demonstrates that IE is a disorder with the epidemiological picture of a chronic disease such as cancer, instead of an acute infectious disease, with a long latent period and possibly several definable intermediates or stages. A new causal model is proposed that includes early bacteremias that may "prime" the endothelial surface of the heart valves over many years, and a late bacteremia over days to weeks that allows adherence and colonization of the valve, resulting in the characteristic fulminant infection.

Animals↗
PubMed1996

The experimental verification of the efficacy of finite element modeling to dental implant systems.

In vitro experimental data of angular displacement vs. applied force were obtained on a fully osseointegrated pair of endosseous implants in a mandible of a macaca mulatta monkey. These data are compared with calculated displacement data for a given force from a three-dimensional finite element model reproducing the geometric structure of a portion of the mandible holding the implants. The displacements show agreement over a range of forces in the elastic region within 3%. The FE model yields a full description of the bending of the implant and the distribution of the stress in the bone surrounding the implants.

Alveolar Process↗
PubMedDate not supplied

Multidimensional causal model of dental caries development in low-income preschool children.

Despite the decline in the incidence of dental caries in the United States over the past several years, the condition remains a significant problem for the nation's poor children. Efforts to identify the factors responsible for caries development in samples of children of low socioeconomic status have primarily focused on a limited number of variables, and those have been predominantly biological (mutans streptococci, for example). Resulting models of caries development have usually shown good sensitivity but poor specificity. They have had limited implications for treatment. In an effort to produce a comprehensive model of caries development, 184 low-income preschool children were clinically assessed for mutans streptococci and for decayed, missing, or filled surfaces of deciduous teeth twice, first at age 4 years (baseline) and again a year later (year 1 assessment). As the clinical assessments were being done, caretakers were being interviewed to obtain data from five domains: demographics, social status, dental health behaviors, cognitive factors such as self-efficacy (self-confidence) and controllability, and perceived life stress. Data were analyzed using a structural equations modeling approach in which variables from all domains, plus baseline decayed missing and filled surfaces and baseline mutants, were used together to create a model of caries development in the year 1 assessment. Results confirmed earlier work that suggested that caries development at a 1-year followup was strongly dependent on earlier caries development. Early caries development in this sample was determined in part by mutans levels and by dental health behaviors. These behaviors themselves were accounted for partly by a cognitive factor. The results support the advantages of employing multidimensional models and provide some direction for intervention to reduce caries incidence.

Causality↗
PubMed2002

Evaluation of maxillary molar distalization with the distal jet: a comparison with other contemporary methods.

Maxillary molar distalization is an increasingly popular option for the resolution of Class II malocclusions. This communication describes the effects of one particular molar distalizing appliance, the distal jet, in a sample of 20 consecutively treated and growing subjects (11 females, nine males; mean starting age of 13) and compares these effects with those of similar devices. Pre- and postdistalization cephalometric radiographs and dental models were analyzed to determine the dental and skeletal effects. The distal jet appliances were constructed using a biomechanical couple to direct the distalizing force to the level of the maxillary first molar's center of resistance. The distal jet was the only appliance used during the distalization phase of treatment. Examination of the cephalometric tracings demonstrated that the crowns of the maxillary first molars were distalized an average of 3.2 mm into a Class I molar relationship. In the process, the first molars were tipped distally an average of 3.1 degrees, however, the amount of tipping in each case was influenced by the state of eruption of the second molar. In subjects whose second molars had erupted only to the level of the apical third of the first molar roots, distal tipping was almost twice that seen when the second molar had completed their eruption. Anchorage loss measured at the first premolars averaged 1.3 mm, but the crowns tipped 3.1 degrees distally because of the design of the appliance. The maxillary incisors were proclined an average of 0.6 degrees with minimal effect on the mandibular plane angle and lower facial height. This study suggests that the distal jet appliance effectively moves the maxillary molars distally into a Class I molar relationship with minimal distal tipping, however, some loss of anchorage is to be expected during this process. The distal jet appliance compares favorably with other intraoral distalization devices and with mechanics featuring mandibular protraction for the resolution of patients with Class II, despite the fact that these types of mechanics address different jaws.

Adolescent↗
PubMed1995

Genetic covariance structure of incisor crown size in twins.

Previous studies of tooth size in twins and their families have suggested a high degree of genetic control, although there have been difficulties separating the various genetic and environmental effects. A genetic analysis of variation in crown size of the permanent incisors of South Australian twins was carried out, with structural equation modeling used to determine the relative contributions of genetic and environmental factors. Maximum mesiodistal crown dimensions of maxillary and mandibular permanent incisors were recorded from dental models of 298 pairs of twins, including 149 monozygous (MZ) and 149 dizygous (DZ) pairs. The analysis revealed that: (i) an adequate fit required additive genetic and unique environmental components; (ii) augmenting the model with non-additive genetic variation did not lead to a significant improvement in fit; (iii) there was evidence of shared environmental influences in the upper central incisors of males; (iv) the additive genetic component constituted a general factor loading on all eight teeth, with group factors loading on antimeric pairs of teeth; (v) unique environmental effects were mostly variable-specific; (vi) most factor loadings on antimeric tooth pairs could be constrained to be equal, indicating a symmetry of genetic and environmental influences between left and right sides; and (vii) estimated heritability of the incisor mesiodistal dimensions varied from 0.81 to 0.91.

Adolescent↗
PubMed2002

A model for dental hygiene education concerning the relationship between periodontal health and systemic health.

PURPOSE: To develop a format for educating the appropriate health care professionals as to the relationships between periodontal inflammation and increased risks for poor diabetes control, cardiovascular disease, cerebrovascular disease, pre-term low birth weight, pneumonia and gastric ulcer reinfection. MATERIALS & METHODS: Dental hygiene students in the Advanced Periodontology curriculum were instructed to review current literature regarding the increased risk for systemic health problems when periodontal inflammation is present. Abstracts of the reviewed material were then presented in group setting to all course participants. For each systemic entity (diabetes, cardio/cerebrovascular disease, adverse pregnancy outcome, pneumonia, gastric ulcer) literature-based evidence of periodontal disease's association, affect, pathogenesis, validity and clinical significance was determined. Consensus statements for each entity were developed and used as a basis for clinical interpretation. Following this, patient health-history materials were developed to obtain the necessary information from patients while educating them about the increased risk for systemic health problems when periodontal inflammation is present. Lastly, correspondence materials were developed to alert managing physicians and medical auxiliaries about the increased risk for systemic problems in their patients who may present with periodontal inflammation. A methodology which medical personnel can use to quickly screen for the presence of periodontal inflammation in at-risk patients was also developed in these correspondences. CONCLUSION: An educational model and clinical materials were developed which are aimed at alerting patients, dental and medical personnel to the increased risk for systemic health problems when inflammatory periodontal disease is present.

Journal Article↗
PubMed1993

Nature and frequency of dental wear facets in an Australian aboriginal population.

The nature and frequency of dental wear facets were studied in a sample of 18-year-old Aborigines, 28 males and 31 females, living at Yuendumu in the Northern Territory of Australia. Facet frequencies were scored indirectly using dental models for all permanent teeth, except third molars, and evidence of non-masticatory tooth grinding in eccentric jaw positions was also recorded. The interplay between attrition and abrasion in an individual over time was assessed by examining facet appearance on serial dental models obtained at approximately yearly intervals from 7 to 25 years of age. Facetting was found to be a very common feature of the Aboriginal dentitions, with frequencies ranging from around 65% for pre-molars to about 90% for molars. Evidence of extreme mandibular movement was noted in 93% of males and 100% of females. The longitudinal observations indicated that wear facet definition varied over time, apparently due to episodes of tooth grinding superimposed on continually-acting abrasive influences. These results show that facetting on teeth associated with extreme mandibular positions and, by inference, the related behaviour of tooth grinding or bruxism are very common features in dentitions of Australian Aboriginals living an essentially non-industrial way of life.

Adolescent↗
PubMed1986

Financial planning and computer modeling in dental practice.

The financial plan describes the practice's financial strategy, projects the strategy's future effect on the practice, and establishes goals by which the practice's manager can measure subsequent performance. The act of putting together a financial plan is called the financial planning process. It is a process that consists of analyzing the practice; projecting future outcomes of decisions that have to be made regarding finances, investments, and day to day operations; deciding which alternatives to undertake; and measuring performance against goals that are established in the financial plan. Computer financial planning models can aid the practice manager in projecting future outcomes of various financial, investment, and operational decisions. These models can be created inexpensively by noncomputer programmers with the aid of computer software on the market today. The financial planning process for a hypothetical practice was summarized, and the financial model used to test out various alternatives available to the practice was described.

Computer Simulation↗
PubMed1991

Classification tree prediction models for dental caries from clinical, microbiological, and interview data.

Caries prediction by Classification And Regression Tree (CART) analysis is an appropriate and powerful alternative or complement to the commonly used classification methods of logistic regression and discriminant analysis, both parametric and nonparametric. The binary classification tree method discussed in this article is designed for complex data and does not require assumptions about the predictor variables or about the presence or absence of interactions among the predictor variables. Furthermore, the results give insight into the structures and interactions in the data and are easy to interpret and apply. In preliminary applications of the CART algorithms to data from The University of North Carolina Caries Risk Assessment Study, the method produced prediction rules having sensitivities and specificities that were similar to or slightly better than those associated with logistic and discriminant analyses. The classification trees constructed tended to involve far fewer predictor variables than required for adequate logistic and discriminant models. For example, for first-grade children in Aiken, South Carolina, nine variables were used to define a prediction rule having 64% sensitivity and 86% specificity. Ten-fold cross-validation estimates for future data were 58% and 79%, respectively. For first-grade children in Portland, Maine, two variables were used to define a prediction rule having 62% sensitivity and 77% specificity. The cross-validation estimates for future data were 58% and 78%, respectively. A brief, and previously unavailable, explanation of the CART method is given for the special case of a dichotomous outcome variable.

Child↗
PubMed2003

Dental class 3 intercept clinic: a model for treating dental class 3 soldiers.

OBJECTIVE: Dental Fitness Classification (DFC) 3 indicates that a soldier has a dental condition that, if not treated, is expected to result in a dental emergency within 12 months. Forty-two percent of Army recruits have DFC 3 conditions as reported by the 2000 Tri-Service Center Recruit Study. Initial entry training schools allow minimal time for dental care. The Fort Hood Class Three Intercept Clinic (CTIC) was created to treat DFC 3 conditions prior to soldiers being assigned to their units. The purpose of this study was to evaluate CTIC's ability to make soldiers dentally deployable before joining their new units at Fort Hood, Texas. MATERIALS AND METHODS: A retrospective review of the CTIC daily sign-in logs for the period of January 1999 to May 2001 was used to identify DFC 3 soldiers. The data were analyzed to determine frequency of DFC 3 by rank, DFC after CTIC visits, distribution of treatment type needed to establish dental readiness, and to identify soldiers whose DFC 3 conditions were not treated. Additionally, for the 6 months between November 2000 and April 2001, all soldiers who remained a DFC 3 when released to their units were followed to assess how long it took for them to attain a DFC 1 or 2 status. RESULTS: The retrospective review of the CTIC records identified 5,851 DFC 3 soldiers who in-processed to Fort Hood from January 1999 to May 2001. CTIC successfully converted 86.9% (N = 5,083) of the soldiers to DFC 1 or 2. Of a sample of 185 DFC 3 soldiers released to their units as a DFC 3, only 54% had converted to DFC 1 or 2, with 60.5 days being the mean days to convert. CONCLUSIONS: Trainees have large demands for dental care with minimal time to seek treatment during Initial Entry Training. A CTIC, or hybrid, can provide the necessary emergent dental care to remove soldiers from DFC 3 prior to their being assigned to their first permanent duty station.

Ambulatory Care Facilities↗
PubMed1999

Characterization of rofecoxib as a cyclooxygenase-2 isoform inhibitor and demonstration of analgesia in the dental pain model.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen, and indomethacin (INN, indometacin) inhibit both the constitutive (COX-1) and inducible (COX-2) isoforms of cyclooxygenase. The induction of COX-2 after inflammatory stimuli has led to the hypothesis that COX-2 inhibition primarily accounts for the therapeutic properties of NSAIDs. METHODS: Chinese hamster ovary (CHO) cell lines that express each COX isoform were used to characterize the in vitro selectivity of rofecoxib. Single oral doses of rofecoxib and indomethacin were then assessed in subjects with use of ex vivo COX-isoform specific assays (serum thromboxane B2 [TXB2] and lipopolysaccharide [LPS]-stimulated whole blood prostaglandin E2 and assays of COX-1 and COX-2 activity, respectively). A double-blind, parallel-group study compared the analgesic efficacy of rofecoxib to placebo and ibuprofen in 102 patients with dental pain. RESULTS: Rofecoxib showed a >800-fold COX-2 selectivity with use of CHO cells that express human COX-1 and COX-2. In subjects, dose- and concentration-dependent inhibition of LPS-stimulated prostaglandin E2 was observed with both rofecoxib (IC50 [the concentration estimated to produce 50% inhibition], 0.77 micromol/L) and indomethacin (IC50, 0.33 micromol/L). Whereas indomethacin inhibited TXB2, (IC50, 0.14 micromol/L), no inhibition was observed with rofecoxib even at doses of up to 1000 mg. In the dental pain study, total pain relief (TOTPAR) over the 6 hours after dosing was similar between 50 mg and 500 mg rofecoxib and 400 mg ibuprofen (P > .20). All active treatments showed greater improvement than placebo (P < .001) CONCLUSIONS: Rofecoxib inhibited COX-2 without evidence of COX-1 inhibition, even at oral doses of up to 1000 mg. Nonetheless, rofecoxib showed analgesic activity indistinguishable from that observed with ibuprofen, a nonisoform-selective COX inhibitor. These results support the hypothesis that the analgesic effects of NSAIDs primarily derive from inhibition of COX-2.

Adult↗
PubMed2006

Biomimetic modification of titanium dental implant model surfaces using the RGDSP-peptide sequence: a cell morphology study.

Surface topography and (bio)chemistry are key factors in determining cell response to an implant. We investigated cell adhesion and spreading patterns of epithelial cells, fibroblasts and osteoblasts on biomimetically modified, smooth and rough titanium surfaces. The RGD bioactive peptide sequence was immobilized via a non-fouling poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) molecular assembly system, which allowed exploitation of specific cell-peptide interactions even in the presence of serum. As control surfaces, bare titanium and bio-inactive surfaces (scrambled RDG and unfunctionalized PLL-g-PEG) were used. Our findings demonstrated that surface topography and chemistry directly influenced the attachment and morphology of all cell types tested. In general, an increase in cell number and more spread cells were observed on bioactive substrates (containing RGD) compared to bio-inactive surfaces. More fibroblasts were present on smooth than on rough topographies, whereas for osteoblasts the opposite tendency was observed. Epithelial cell attachment did not follow any regular pattern. Footprint areas for all cell types were significantly reduced on rough compared to smooth surfaces. Osteoblast attachment and footprint areas increased with increasing RGD-peptide surface density. However, no synergy (interaction) between RGD-peptide surface density and surface topography was observed for osteoblasts neither in terms of attachment nor footprint area.

Animals↗