Ceramic laminate veneers: continuous evolution of indications.
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Dental Marginal Adaptation↗
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Impression matrix technique for cusp replacement using direct composite resin.
UNLABELLED: Placement of Class II composite resin restorations often presents unique challenges in achieving proper contour and contact. Although the use of sectional bands has provided solutions to these problems, their use typically is limited to more ideal cavity preparations. With more extensive loss of tooth structure, recreating the natural tooth contours and contacts with direct resin composite can be difficult. Typically an indirect restoration is the treatment of choice when a cusp is lost. However, situations may arise that require the use of direct resins for cusp replacement. This article describes the use of an impression matrix to facilitate the replacement of missing tooth structure and allow the dentist to use sectional bands in certain cusp loss situations. CLINICAL SIGNIFICANCE: When applicable, the impression matrix provides a significant saving in time and effort in cusp replacement with direct composite resins.
Bicuspid↗
Cracked tooth syndrome.
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Cracked Tooth Syndrome↗
The effects of Ledermix paste as an intracanal medicament on the discolouration of teeth.
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Anti-Bacterial Agents↗
Considerations in intracoronal bleaching.
Intracoronal bleaching is a simple, useful procedure for restoring the colour of discoloured root-filled teeth that are not extensively restored. It is important to minimise the extraradicular diffusion of hydrogen peroxide, as excessive levels of hydrogen peroxide in conjunction with existing inflammatory changes in the periodontium predispose the tooth to external root resorption. To keep the levels of extraradicular diffusion of hydrogen peroxide below the safety limit, it is imperative that an effective intermediate base cement of at least 2 mm be placed at the level of the buccal cemento-enamel junction over the root-filling prior to bleaching. The use of 35% carbamide peroxide as the intracoronal bleaching agent seems to combine the safety of sodium perborate together with the efficacy of 35% hydrogen peroxide. As bleaching agents may reduce the composite-tooth bond of some adhesive systems, the post-bleaching composite restoration should be delayed for at least three weeks.
Borates↗
Consequences of success: do more teeth translate into more disease and utilization?
OBJECTIVES: Increased tooth retention coupled with increased numbers of older adults means that the actual number of teeth at risk to dental disease will increase sharply. Whether this increase in the number of teeth will translate into more disease and utilization in unknown. The purpose of this study was to test this "more teeth, therefore more dental disease" theory using cross-sectional data. METHODS: In-home personal interview and oral examination data were obtained on a probability sample of elders aged 70 years and older living in the six New England states using the Medicare beneficiary list as a sampling frame. Data on dental utilization, number of teeth, dental caries, and periodontal disease were included in the current analysis. RESULTS: Analysis of variance on subjects with 1-10 (Group 1), 11-24 (Group 2), and 25-32 (Group 3) teeth show that the extent of bleeding on probing, pocket depth, and loss of attachment all increase as numbers of teeth increase. Similarly, a greater number of restored coronal and root surfaces were found in Group 3 relative to the other two groups. Mean numbers of decayed and filled coronal surfaces were 8.4 in Group 1.33.0 in Group 2, and 50.3 in Group 3. In contrast, unrestored coronal and root surface were significantly higher in Group 1 (mean root DS = 1.3) than Group 3 (mean root DS = 0.3). Utilization patterns of those with successful aging dentitions (Group 3) show that they are visiting dentists more frequently than the compromised group (Group 1). CONCLUSIONS: These cross-sectional data obtained from a probability sample of New England elders show that subjects who retained higher numbers of teeth have more periodontal disease and dental caries experience, and visit the dentist more frequently.
Aged↗
The strength of two indicators of social position on oral health among persons over the age of 80 years.
OBJECTIVE: The objective of the present study is to analyze how two dimensions of social position, education and social class, are associated with oral health among generally healthy, community-dwelling persons over the age of 80 years. METHODS: The present investigation is based on a sample of 157 community-dwelling individuals from The Kungsholmen Elders Oral Health Study (KEOHS) and included data from interviews and oral examinations. Social position was measured by education and social class. Oral health was measured by active coronal caries, active root caries, edentulism and use of dental services. RESULTS: The primary findings of the adjusted multivariate logistic regression analysis were that, compared to persons who had been in higher positions, persons who had been blue-collar/ white-collar workers had significantly greater odds of having coronal caries and high, but nonsignificant odds of being edentulous. Further, persons with elementary/ medium education tended to forego regular dental services more than persons with high education. CONCLUSION: The study identified social inequalities in oral health even in a population of independently living, generally healthy very old Swedes and in a country where the public health policies have tried to minimize these inequalities.
Age Factors↗
The relationship between cardiovascular xerogenic medication intake and the incidence of crown/root restorations.
OBJECTIVES: This retrospective, longitudinal cohort study quantified the strength of the association between xerogenic cardiovascular medication use and dental restorations, using the latter as a proxy measure for dental caries experience. METHODS: Study data were collected from 11 years of electronic clinical/pharmacy records in two large dental group practices associated with managed care organizations (MCO). Records were extracted for all members who were at least 55 years old at the end of the 11 year window, and had at least 48 months of concurrent dental, medical, and pharmacy coverage. The authors identified 4448 individuals whose only xerogenic medication exposure was to drugs treating a cardiovascular condition. This group was compared to a group not taking any medications (n=1183), and a group taking medications with no known xerostomic side effect (n=5622). Poisson regression compared restoration incidence and mean restoration rates among the three groups. RESULTS: MCO members taking cardiovascular or nonxerogenic medications had higher restoration incidence and mean restoration rates than individuals taking no medications. A small difference in mean restoration rate between the non-xerogenic medication group and the cardiovascular drug group was observed; no significant difference in restoration incidence was seen between these two groups. CONCLUSIONS: This study provides objective quantification of cardiovascular medication's long-term effects on increased restorations in older adults. When grouped under a single category labeled "cardiovascular", drugs with effects targeting the cardiovascular system did not appear to unequivocally lead to higher restorative experiences.
Aged↗
Coronal displacement of cementum: correlation between age and coronal movement of cementum in impacted teeth.
This study was conducted on 48 impacted and 51 erupted maxillary permanent canine teeth extracted from healthy patients aged 13-73 years. Longitudinal buccolingual ground sections were prepared. The distance between the edges of cementum and enamel in each specimen was measured with an eyepiece micrometer. A correlation test was applied between age and the distance between enamel and cementum measurements. In impacted teeth, depending on age, cementum had a tendency to overlap the enamel; there was a linear correlation between age and coronal displacement of cementum (n-2 = 46, r = 0.69, distance (microgram) = 21.7* age (years) -440, p < 0.001). No correlation between age and coronal displacement was found in erupted teeth (n-2 = 49, r = -0.23, p > 0.05). Results of the study indicated that the cementum in impacted teeth migrated coronally during the ageing process. This may be related to continually erupting forces which affect the impacted teeth and may be a mechanism by which the teeth are protected at the cemento-enamel junction (CEJ). This phenomenon could be used in forensic dentistry to determine age. The absence of correlation in erupted teeth could be attributed to the masking effects of extrinsic factors.
Adolescent↗
Pericoronal radiolucencies and the significance of early detection.
Pericoronal radiolucencies are common radiographic findings encountered in general dental practice. They usually represent a normal or enlarged dental follicle that requires no intervention; alternatively they may represent a pathological entity that requires appropriate management and histopathological interpretation. A pericoronal space of greater than 2.5mm on an intraoral radiograph and greater than 3mm on a rotational panoramic radiograph should be regarded as suspicious. Although many pathological processes may present radiographically as pericoronal radiolucencies associated with unerupted teeth, the most common is the dentigerous cyst. These lesions may enlarge considerably if allowed to develop unchecked, and have the potential for pathological transformation. In this report we present four cases of large pericoronal radiolucencies associated with unerupted teeth, and highlight the importance of early detection and management of such lesions.
Adult↗
A proposal for a new classification of lesions of exposed tooth surfaces.
In the presence of improved methods of identification and treatment of lesions on the exposed surfaces of teeth, it should now be acknowledged that the GV Black "classification of carious cavities" is out of date. This paper describes a new system, proposed in 1997, discussed broadly throughout the profession, and eventually modified. The system has been adopted in several regions around the world as being a useful corollary to the current developing concept of minimal intervention dentistry. It is now desirable to adopt a new approach to the identification and recording of the lesions caused by both caries and non-carious tooth loss. A major advantage arising from its adoption would be that it would encourage the profession to minimise the amount of normal healthy tooth structure that is often sacrificed in pursuit of the cavity designs as suggested by Black. The authors are members of a Project Group of the FDI Science Committee, and this paper explains the concept and offers justification for the adoption of the system.
Dental Caries↗
Evaluation of a laryngoscope and a rigid endoscope for the examination of the oral cavity of small mammals.
The oral cavities of 65 rabbits, 35 chinchillas, 38 guinea pigs, 19 degus and 13 prairie dogs suffering from a lack of appetite, hypersalivation, moist dermatitis, swelling of the lower jaw or mild exophthalmos were examined with a paediatric laryngoscope and rigid endoscope. The laryngoscope was safe and satisfactory for a preliminary examination, but changes in the less accessible caudal parts of the cavity could not be identified precisely. A rigid endoscope with 30 degrees optics made it possible to examine all parts of the oral cavity and oropharynx, and make detailed observations of surface lesions on the premolar and molar teeth and the mucosal surface of the gingiva, tongue and hard palate; endoscopy with 70 degrees optics provided an excellent view of the occlusal tooth surfaces, tooth crowns, and buccal mucosa. The collection of biopsy samples, the removal of foreign objects and the correction of malocclusions were greatly simplified by the use of the endoscope owing to the clear visualisation of the procedures, and the risk of injury was minimised. The examinations with a laryngoscope were made effectively on animals that were manually restrained, but a thorough examination with a rigid endoscope required the animals to be anaesthetised.
Anesthesia↗
A Raman spectroscopic investigation of dentin and enamel structures modified by lactic acid.
Confocal Raman microspectrometry allows a thorough molecular analysis of mineralised dental tissues. The output information is provided in the form of curves representing the intensity of the signal according to the frequency, and its mathematical exploitation permits all sorts of comparative and quantitative analyses. By this process, we investigated the in vitro action of lactic acid on enamel and dentin from human permanent teeth. Modifications due to the acidic attack essentially concern phosphate grouping PO(4)(3-), which represents the mineral phase in enamel and dentin (hydroxyapatite): on Raman spectra, changes in intensity of the PO(4)(3-) band are linked to the type of dentin, to its anatomical location, and to the age of the subject. The variability of the dentinal chemical structure was confirmed by a quantitative statistical analysis, revealing a significant spectral difference between coronal and root dentin.
Adult↗
Thickness measurement of worn molar cusps by ultrasound.
This study aimed to evaluate the effectiveness of an ultrasonic system for in vitro measurement of cusp tips of human teeth. Each worn cusp of 12 molar teeth was measured with an industrial ultrasonic system. The teeth were sectioned and measured by polarized light microscopy. The ultrasonic measurements and histological readings were moderately correlated (r = 0.601, p < 0.01). The ultrasonic system used in this study seemed a promising method for measuring thickness of worn cusp tips of extracted human molar teeth.
Dental Enamel↗
Diagnosis of erosive tooth wear.
The clinical diagnosis 'erosion' is made from characteristic deviations from the original anatomical tooth morphology, thus, distinguishing acid induced tissue loss from other forms of wear. Primary pathognomonic features are shallow concavities on smooth surfaces occurring coronal from the enamel-cementum junction. Problems from diagnosing occlusal surfaces and exposed dentine are discussed. Indices for recording erosive wear include morphological as well as quantitative criteria. Currently, various indices are used making the comparison of prevalence studies difficult. The most important and frequently used indices are described. In addition to recording erosive lesions, the assessment of progression is important as the indication of treatment measures depends on erosion activity. A number of evaluated and sensitive methods for in vitro and in situ approaches are available, but the fundamental problem for their clinical use is the lack of re-identifiable reference areas. Tools for clinical monitoring are described.
Acids↗
A new technique for screening chemical toxicity to the pulp from dental restorative materials and procedures.
An in vitro test system is described which allows for quick and relatively inexpensive examination of the potential for chemical toxicity to the pulp of materials and procedures used in the restoration of single teeth. The test system consisted of two sequential steps. First, a restorative procedure was carried out on a freshly-extracted human tooth crown, to the pulpal surface of which had been attached a chamber filled with sterile tissue-culture medium. The preparation was kept at 37 degrees C. The culture medium was removed at day one and replaced with fresh medium, which was removed at day 3. In the second step, we used a standard tissue-culture toxicity assessment technique to examine both culture medium samples for the presence of chemical toxins. In use, this system gave results which correlated well with the known clinical potential for pulpal toxicity of various dental materials and techniques. For example, zinc oxide-eugenol used as temporary filling or base had no apparent potential for toxicity. Sealing a cotton pellet containing phenol into a cavity was of high apparent potential toxicity. Acrylic resin as intracoronal or extracoronal fillings showed potential for toxicity; this potential was decreased by lining with calcium hydroxide cement. Composite resin placed onto etched dentin had apparent toxic potential, but had less such potential when placed onto unetched dentin. The technique had some advantages over previously described in vitro toxicity test for restorative materials, because it included a step requiring diffusion of potential toxins into and through human dentin, and because it allowed for examination of variations in technique which mimic clinical behavior, and of materials used in sequence or in combination.
Adolescent↗
Effect of hydrostatic pressure on the diffusion of monomers through dentin in vitro.
In previous work, the diffusion of monomers from composite and bonding resins through dentin was demonstrated in vitro. The monomers triethylene glycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) were identified in samples from the pulp space. In the current study, we examined the effects of two levels of positive hydrostatic pressure on the passage of resin monomers through dentin in vitro from a composite-resin/bonding-resin combination to test the hypothesis that monomer diffusion is prevented by such pressure. An occlusal cavity prepared in the tooth crown was restored with the resins. Distilled water samples from the pulpal space were removed over time and analyzed for monomer content by high-performance liquid chromatography and mass spectrometry. Positive pulpal pressure reduced but did not prevent pulpward movement of diluent monomers that leach from bonding agents and from resin composites through dentin in vitro. The degree of reduction of diffusion was greater with TEGDMA than with the lower-molecular-weight monomer HEMA.
Adolescent↗
Morphometric analysis of the primary and permanent dentitions in hemifacial microsomia: a controlled study.
Hemifacial microsomia (HFM), a developmental abnormality involving the first and second branchial arches, is one of the most common craniofacial abnormalities. Although the general presentations of hemifacial microsomia--such as unilateral microtia, macrostomia, and hypoplasia of the mandibular ramus and condyle--are wellknown, the effects on the teeth are not well-documented. This study examined the primary and permanent tooth dimensions of dental casts of 50 hemifacial microsomia patients compared with those of 50 normal control patients matched for sex and dental status. The results showed that the mesiodistal dimensions of the mandibular second primary molar and the mandibular permanent first molar teeth on the affected side in hemifacial microsomia were significantly smaller compared with those of control teeth (p < 0.001). Furthermore, in the maxillary and mandibular first permanent molars and the maxillary and mandibular first and second primary molars, the teeth in the apparently "normal" side of hemifacial microsomia were also significantly reduced in the mesiodistal dimensions. Comparison of overall dimensions revealed that all primary and permanent molars in hemifacial microsomia were significantly smaller in the mesiodistal dimensions compared with control teeth. A general gradient effect was observed, with the most posterior tooth in each arch being the most severely affected and no effect being seen in the canines and the incisors. These findings suggest that the dental lamina in hemifacial microsomia is affected, and support the hypothesis that its pathogenesis involves an abnormality of the neural crest. Furthermore, these results also support the concept that hemifacial microsomia is a bilateral rather than a unilateral condition.
Branchial Region↗