摘要:

The common methods of age determination with the aid of teeth have been criticized because they rely on subjective estimations of tooth development, as seen in radiographs, and subsequent comparisons with pictures and descriptions in compiled dental charts. The distribution around an estimated age with these methods is usually more than ±2 yr between the 10th and 90th percentiles. In an attempt to avoid subjective estimations, objective measurements of developing teeth were correlated with subjects' chronologic ages. The structures measured were crown height, apex width, and root length. With the aid of a multiple regression model, a linear relationship between some of these distances and age was shown. The distances which were best correlated with age differed according to sex and age. This method has a 95% C.I. of about ±2 yr around an estimated age. It therefore seems to be more accurate than the earlier methods. Thus, the individual variation in tooth development is of the same order of magnitude, and a better estimation can therefore not be done in children 6–14 yr of

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01169.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

The properties of dentin are strongly influenced by the so‐called smear layer. This layer is always present on the dentin surface after cutting, drilling, sawing, etc. The smear layer can be removed by various chemical treatments, such as those of acid etching or ethylenediaminetetraacetic acid (EDTA). These treatments remove the smear layer and open the tubules. In this paper, the effect on the smear layer of human dentin of treatment with a 2% glutardialdehyde (GDA) solution at pH 3.5 for 2 min and a 0.5‐M EDTA solution at pH 7.4 for 4 min was investigated by scanning electron microscope (SEM). The dentin samples were dried by air or critical‐point drying before SEM photography was employed. The number of open dentin tubules was quantified on micrographs of EDTA‐ and GDA+EDTA ‐treated dentin. The results show that the GDA treatment fixed part of the smear layer and the superficial dentin surface in such a way that at least 50% of the tubules remainedclosedafter EDTA treatment. By closing the dentinal tubules, the GDA‐fixed layer might have a positive effect on dentin hypersensitivity, root caries, and bonding of composit

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01170.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

A study was performed to assess the variations among dentists in the performance of tunnel preparations for “caries” removal and cavity design, and to evaluate how these variations are affected by instruction and training. Twenty‐seven dentists with limited clinical experience in performing tunnel preparations participated in the study. They did three partial tunnel preparations each in extracted premolars with standardized, artificial, approximal “carious lesions”. The first preparation was made without instruction, the second after instruction and under supervision, and the last without supervision. After information/supervision, 26% did not manage to do a tunnel preparation without residual caries, indicating that this is not an easy procedure for beginners. The occlusal opening was significantly larger and the width of the remaining approximal wall was significantly smaller in preparations without “residual caries” than in those exhibiting “residual caries”. Visibility appears to be improved by extending the occlusal opening toward t

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01171.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Root surface texture after scaling with hand instruments, ultrasonic scalers (Amdent 830 and Cavi‐Med 2000), and a sonic sealer (Titan‐S) was assessed in vitro. The experimental material consisted of 48 extracted human teeth divided into six groups. Root surface texture was assessed with scanning electron microscopy (SEM). Hand and sonic instrumentation produced large grooves and removed cementum evident at a magnification of ×70. while the root surface alterations after ultrasonic instrumentation were not detectable below a magnification of ×500. The working principle of each scaling instrument in relation to its effect on the root surface was disc

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01172.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

This study introduces a strategy to identify and produce sequences useful as genetic markers, or native genetic probes for DNA‐DNA hybridization in bacterial strains where the genetics is not well described.Actinobacillus actinomycetemcomitans (A.a.) was used as an example. Fifty ng genomic DNA fromA.a. ATCC 33384 andHaemophilus aphrophilusATCC 33389 was amplified in a thermocycler using a single 10‐mer primer. The PCR products were separated by electrophoresis on a 1% submarine agarose gel containing ethidium bromide and visualized by UV illumination, and the strain‐specific amplitypes were compared. DNA from two bands, 0.9 and 4 kb, unique for theA.a. strain, was cut out, amplified under high stringency with the same primer and labeled by replacing 33.3 μM dTTP with digoxigenin‐labeled dUTP in the reaction mixture. The labeled probe was then repeatedly used for hybridization to DNA from variousA.a., H. aphrophilus, and other bacterial strains of the Pasteurellaceae family. The results showed that the 0.9‐kb probe detected allA.a. tested, and distinguished it from other closely related bacterial species. We conclude that the described strategy is useful for identifying and selecting genetic sequences useful as genetic mar

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01173.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

By administering a questionnaire to 253 patients with cardiac‐valve prostheses (89.3% responding), and another to 136 of their attending dentists (79% responding), the level of knowledge among both groups of anticoagulant therapy in connection with dental treatment was investigated. The cardiothoracic department monitored all anticoagulation therapies. Of the anticoagulated patients, 96.6% were able to state their medication (94.1% received phenprocoumon); and of 86 dentists with patients on anticoagulation treatment, 94% were aware of their patients' medication. All 20 dentists stating that their patients did not receive anticoagulants were correct. The great majority (98%) of the dentists employed a special measure to reduce the risk of bleeding associated with invasive dental procedures, most commonly (86%) referring patients to their general practitioner or hospital department for adjustment of the anticoagulant therapy. Around 60% of the dentists considered extractions and operations to require measures to reduce the risk of bleeding complications. We recommend referral of patients to the attending physician for adjustment of anticoagulation to a target International Normalized Ratio (INR) of 4.0 or possibly 3.0 before undergoing dental procedures involving the risk of bleeding. Additional reduction of the bleeding risk can be obtained by local application of an inhibitor of fibrinolysis (tranexamic acid

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01174.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Fifty‐one consecutive patients had clinically diagnosed oral lichen planus (OLP) lesions in total or partial contact with amalgam fillings. The clinical features of the OLP lesions were characterized and registered, and biopsies were obtained from each OLP lesion. Histologic and immunohistochemical studies were performed, as well as tests for allergy to dental materials. The clinical diagnosis of OLP corresponded to the World‐Health Organization (WHO) morphologic OLP criteria in 31 (61%) cases. The remaining lesions were histologically diagnosed as mild OLP in 11 (22%) or as benign oral keratosis in nine (17%) cases. The immunohistochemical examination showed a positive reaction to fibrinogen in the basement membrane zone (BMZ) in 10 (20%) patients and to complement C3 in one (2%) patient. No positive reactions in the BMZ were found for IgA, IgG, and IgM. In 17 (33%) patients, an allergic reaction to mercury was found, and candidiasis was diagnosed in 13 (25%) patients. The true nature of OLP‐like lesions in contact with amalgam fillings still remains to be explained. For that matter, we do not know whether OLP is one disease or a number of similar immunologic or other responses to various interacting stimuli. One such stimulus might be mercury from corroding amalgam fil

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01175.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

The aim was to study the influence of mouthrinses with glucose, at concentrations ranging from 1 to 50%, on oral retention at two different locations in the oral cavity. Salivary secretion was reduced in 10 subjects by injection of methylscopolamine nitrate submucosally. The volunteers were randomly assigned to rinse with 10 ml of either 1%, 10%, or 50% glucose solution for 30 s, after which measurements of glucose concentration and parotid salivary secretion rate were performed during a 10‐min period. The results showed higher salivary glucose levels vestibularly than sublingually. The difference in glucose retention between the two locations increased when the salivary flow rate recovered. The relationship between secretion rate and area under the curve for glucose measured sublingually, but not in the vestibule, was bilinea

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01176.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

The aim of this study was to evaluate the clinical performance of four types of tooth‐colored inlays. The systems included 15 direct ceramic inlays (CEREC Vita‐Blocks), 15 direct composite inlays (Brilliant D.I., Coltène), 14 indirect ceramic inlays (Vita Dur N), and 14 indirect composite inlays (Estilux) in 37 patients. The inlays were evaluated clinically 1 wk (base line) and 6 and 12 months after cementation. The clinical assessments were supported by bitewing radiographs. One Vita Dur N inlay fractured after 1 yr of service, and one Brilliant D.I. inlay had to be replaced because of secondary caries. No apparent increase in plaque accumulation or gingival inflammation could be related to treatment with inlays. At base line and throughout the observation period, the Vita Dur N inlays received the highest ratings for morphology and color match. The Brilliant D.I. inlays showed the smoothest surface texture, whereas the Estilux inlays showed the roughest texture. After 6–12 months of observation, all types of inlays showed varying degrees of disintegration of the composite luting cement. Within the observation period, all inlay systems appeared to be clinically acce

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1994.tb01177.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY