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At least 703 records · Page 39Linked to original sources
PubMed2003

Secular changes in tooth size and dental arch dimensions in the mixed dentition.

Secular changes in the mixed dentition were studied. Permanent tooth size and dental arch dimensions were examined in Norwegian children born in the 1960s and 1980s, Swedish children born in the 1960s and 1980s, Norwegian Sami children born in the 1980s, and a sample of Norwegian skulls dating from the 14th to the 19th century. The Norwegian Sami children were nomadic in the summertime. A sample of pigs was studied before and after a maceration process to determine what dimensional changes might occur in such a process. A shrinkage of 0.3%-1.7% was found. This information was used when the skulls were compared with the modern groups. Lateral dental arch lengths were shorter in the children born in the 1960s compared with the children born in the 1980s. This was a result of the higher prevalence of caries in the second deciduous molars in the 1960s groups. Children who had lost a deciduous canine prematurely were found to have smaller dental arch perimeters. When compared with other data, this was blamed on a pre-existing crowding. Permanent tooth size was smaller in the skulls compared with the modern groups. Improved nutrition is considered to be the main reason for the difference. Relative dental arch space differed in the group born in the 1960s from that in the other groups, indicating a greater prevalence of crowding in the former. Relative dental arch space in the skulls and in the group born in the 1980s was similar. A more traditional way of living, as practised by the Sami group in this thesis, was not favorable for relative dental arch space. The transverse intermaxillary relation in boys changed from the 1960s to the 1980s, which indicated that the 1980s group ran a greater risk of developing a posterior cross-bite. Before the same conclusion could be made in the girls, the mesial drift of the first permanent molars had to be corrected for, because of a higher prevalence of caries in the 1960s group. The sex-pooled analysis of the skulls and the contemporary groups revealed that the risk for developing a posterior cross-bite in the 1980s group was greater than in the skulls. The skulls had smaller arch depths than the modern groups.

Adolescent↗
PubMed2003

Fracture strength of cusp replacing resin composite restorations.

PURPOSE: To assess the influence of an additional shoulder preparation on the fracture strength of a cusp-replacing direct resin composite restoration in a premolar that previously had an amalgam MOD restoration followed by fracture of a cusp. MATERIALS AND METHODS: Two preparation designs were tested. In extracted sound premolars an MOD amalgam cavity was simulated followed by fracture of a cusp (Group A). Group B was the same as Group A but a shoulder was added along the cervical outline of the preparation. As a control group, cusp fracture was simulated but no MOD amalgam cavities were prepared. For each group, 14 preparations were made using a copy milling technique. All 42 preparations were restored using a direct resin composite restoration technique. Restorations were loaded until fracture. RESULTS: The fracture strength of the preparation with shoulder was not significantly different from the preparation without the shoulder. The fracture strength of the preparations in the reference group, which had no resistance form, was significantly less than in Groups A and B (ANOVA, P<0.05).

Analysis of Variance↗
PubMed2003

Multiple dental anomalies in the maxillary incisor region.

A patient with multiple anomalies of the maxillary teeth, including shovel-shaped incisors, talon cusp, bilateral dens invaginatus and bilateral peg-shaped supernumerary incisors is reported. The patient also exhibited Carabelli's cusp on both maxillary first molars. No developmental syndrome was identified. This very unusual combination of anomalies has not been reported previously.

Adult↗
PubMed1992

The Periotest method.

The Periotest is a new instrument for the diagnosis of periodontal diseases. The 'Periotest value' depends to some extent on tooth mobility, but mainly on the damping characteristics of the periodontium. The Periotest measures the reaction to a reproducible impact applied to the tooth crown. The Periotest value is a biophysical parameter.

Electronics, Medical↗
PubMed2003

Adhesive reattachment of a tooth fragment: the biological restoration.

Recent developments in restorative materials, placement techniques, preparation design, and adhesive protocols allow clinicians to predictably restore fractured teeth. Using a minimally invasive approach, treatment of the maxillary anterior region can be effortlessly completed within a single appointment. If the original tooth fragment is retained following fracture, the natural tooth structures can be reattached using adhesive protocols to ensure reliable strength, durability, and aesthetics. This article discusses the adhesive reattachment of a tooth fragment to a fractured incisor using a conservative preparation technique.

Child↗
PubMed2003

Coronal microleakage assessed by polymicrobial markers.

Studies have shown significant bacterial leakage following exposure of sealed root canals to artificial and natural saliva. The objective of this study was to determine contamination via bacterial migration in artificial saliva in endodontically treated teeth using different obturation techniques and sealers. A total of 144 extracted, human mandibular anterior teeth were cleaned and shaped to a #40 master apical file using hand and rotary instrumentation. One hundred and twenty teeth were divided into two experimental groups. The teeth in Group 1 were obturated with gutta-percha using lateral compaction and five different sealers, and the teeth in Group 2 were obturated with gutta-percha using thermomechanical compaction and five different sealers. The remaining 24 teeth were prepared as positive and negative controls. All specimens, except the negative controls, were inoculated every five days with Anaerobic streptococci (NCTC 9891) related to Peptostreptococcus micros and Prevotella intermedia (ATCC 25611). The contamination onset time was continuously recorded and turbid broths cultured for bacteria identification. The controls behaved as expected. Regardless of the combination between obturation techniques and different sealers, all broths became turbid during this experiment. The correlation between the obturation techniques and the sealers revealed statistical significance using ANOVA (p<0.0001), followed by the Duncan Multiple Range Test, which determined the ranking between these interactions. The combination of MicroSeal obturation technique with Ketac-Endo sealer allowed a slower rate of coronal-apical bacterial migration.

Analysis of Variance↗
PubMedDate not supplied

Interproximal contact points and proximal caries in posterior primary teeth.

PURPOSE: The purpose of this study was to investigate the hypothesis that the risk of proximal caries in posterior primary teeth is higher when interproximal contact points are closed than when they are open. METHODS: A cross-sectional study design was used with a sample of 286 children aged 24 to 72 months (mean age 54 months +/- 16 months). Children with any permanent dentition were excluded. Caries (defined as a lesion halfway through enamel or further) was assessed radiographically by a single dentist. The open/closed nature of contact points was assessed by a different dentist through resistance to dental floss. Data concerning known risk factors and indicators for caries were also collected. Analyses were performed at the level of the contact point, comparing the same contact points in different children. Multiple logistic regression was used to asses the relationship between open/closed status and caries status for each posterior contact point. RESULTS: In 7 of the 8 contact points examined, the odds for caries were significantly increased when contact points were dosed. CONCLUSIONS: This research suggests that the risk for proximal caries in the posterior primary dentition is raised if contact points are dosed compared to those that are open.

Bottle Feeding↗
PubMedDate not supplied

Fracture resistance of teeth with Class II bonded amalgam and new tooth-colored restorations.

This study compared the cuspal fracture resistance of posterior teeth restored with four different adhesive restorations. Fifty sound, maxillary human premolars were randomly divided into a control group and four experimental groups with 10 teeth in each. Specimens in the first group were intact teeth that were tested as unprepared. The remaining four groups received mesio-oclusodistal cavity preparations and were restored with a hybrid composite (Filtek Z250), a packable composite (Filtek P60), an ormocer (Definite) and an amalgam (SDI Permite) with an amalgam bonding agent (Amalgam Bond Plus). All groups were stored in water at 37 degrees C for 15 days and thermocycled 1000 times between 5 degrees-55 degrees C. The specimens were preloaded five times in compression to 10 kg using two metal rods that contacted only the teeth on the cuspal inclines. The teeth were then loaded occlusally in an Instron Universal Testing Machine until fracture occurred. The means of force required to fracture the teeth in each of the five groups was analyzed using one-way ANOVA and Tukey Test. The difference between the mean cuspal fracture resistance of the unprepared control teeth and those restored with amalgam groups was found to be statistically significant (p < 0.05). No significant differences in resistance to cuspal fracture were found among the restoration groups, the unprepared control group and those teeth restored with hybrid composite, packable composite and ormocer groups (p > 0.05).

Analysis of Variance↗
PubMed2003

Cerec veneers--practical procedure and case presentation.

The Cerec method offers experienced users the possibility of accomplishing veneers chairside which are capable of meeting the highest functional and esthetic requirements. "Esthetic shaping" directly on the patient requires a good eye for color and form, and this requires training. The present report outlines the clinical procedure and presents three clinical cases step by step, specifically discussing the external staining technique with Pro-CAD blocks.

Adolescent↗
PubMed2003

Prediction of the size of un-erupted permanent cuspids and bicuspids in a Saudi sample: a pilot study.

The purpose of this study was to produce an estimated equation for the prediction of unerupted cuspids and bicuspids for the Saudi population. In this study, dental casts of 65 Saudi subjects (37 males and 28 females) were used. The subjects' age ranged from 18 to 25 years. The mesiodistal width of all permanent teeth was measured. The data was subjected to regression analysis. Results showed the Tanaka and Johnston equations overestimate the predicted tooth width of the un-erupted cuspids and bicuspids in Saudis. Results showed the predicted tooth width of Saudis (males and females) is closer to the 50% level of confidence in Moyer's chart. Multiple regression equations were estimated including the sex factor. Accordingly, two equations were estimated for the prediction of the tooth width of the un-erupted cuspids and bicuspids for the Saudi males and females. Based on the results, it can be concluded the 50% data is more accurate than the commonly used percentage Moyer's table (75%) when both sexes are combined. Further studies are needed to confirm the findings of this study.

Adolescent↗
PubMed2003

Tooth fragment reattachment--an esthetic alternative: report of a case.

Trauma to the anterior teeth is relatively common among children and teenagers. Reattachment of a fractured fragment to the remaining tooth can provide better and long lasting esthetics, improved function, a positive psychological response and is a faster and less complicated procedure. This article discusses fragment reattachment technique and presents clinical case of coronal fracture involving enamel and dentin.

Acid Etching, Dental↗
PubMed2002

[Experimental study of the effect on marginal seating of the castings by different investing methods].

OBJECTIVE: The purpose of this study was to observe the effect on marginal seating of the castings with and without ring investments. METHODS: Standarded as-cast specimens and round capsules simulated post tooth crowns were made. 12 wax pattern were prepared on the as-cast specimens. The 12 specimens were divided into two groups with 6 wax pattern in each group. Two different investing methods with the same investing material were tested. The marginal seating of the castings was measured under travelling microscope. RESULTS: The marginal seating of the casting without ring investment had significant difference compared with the castings with ring investment (P<0.05). CONCLUSION: Casting without ring can improve the marginal seating of the castings.

English Abstract↗
PubMedDate not supplied

Contemporary implant concepts in aesthetic dentistry--Part 2: Immediate single-tooth implants.

Immediate implant placement and provisionalization in the aesthetic region has demonstrated predictable long-term results. Use of the immediate loading protocol significantly reduces the need for a second surgical intervention following implant placement. Based on the patient's preoperative condition, this technique can also be incorporated in select cases without the need for complicated bone grafting and augmentation procedures in compromised ridges. This article discusses the placement of single-tooth implants in the anterior region and presents the advantages and limitations of the immediate placement protocol.

Adult↗
PubMedDate not supplied

The nano-hardness and elastic modulus of carious and sound primary canine dentin.

This study measured the nanohardness and elastic modulus- of carious and sound primary canine dentin and compared the values obtained under the lesion and in sound regions of incisal, center and cervical areas, and outer, middle and inner layers. Six extracted or exfoliated primary canines (three with dentin caries on both proximal surfaces and three sound teeth) were mesiodistally sectioned parallel to the long axis of the tooth and polished. The hardness (H), plastic hardness (PH) and Young's modulus (Y) were measured by a nano-indentation tester. Ten indentations at intervals of 10 microm on all regions, areas and layers were made using a load of 1 gf for one second. All indentations were observed using a microscope attached to the tester. All data were statistically analyzed using ANOVA and Scheffe's test at p < 0.05. For sound teeth, the H, PH and Y values of the inner layer were significantly lower than the outer and middle layers in all areas. The H, PH and Y values of the cervical area were significantly lower than the incisal area in almost all of the outer, middle and inner layers. For carious teeth, the H, PH and Y values of the inner layer were significantly lower than the outer and middle layers in the center area. For the center area, the H, PH and Y values under the lesion were significantly lower than sound teeth in the outer and middle layers. Dentin under the lesion, near the pulp and cervical areas showed significantly lower nanohardness and elasticity.

Analysis of Variance↗
PubMedDate not supplied

Consequences of posterior cusp fracture.

Although posterior cusp fracture occurs frequently, its consequences are not well-delineated. This study recorded short-term outcomes (distribution of fractured teeth and cusps, fracture severity, and treatment received up to two years postfracture) for 517 fractured teeth from 498 subjects at a large group practice. Maxillary and mandibular tooth fractures occurred with similar frequency. In the maxillary arch, first and second molars and premolars fractured with roughly the same frequency; premolar fractures were more severe. In the mandible, first molars accounted for approximately 50% of all fractures and were most likely to be severe fractures. Nonholding cusps were more likely to fracture in both arches. Proportions of fractured teeth receiving "catastrophic" treatment were low (3% extraction; 4% endodontic treatment) and the large majority of fractured teeth were treated in a single visit using direct restorative materials. A knowledge of the relatively small proportions of fractured teeth that suffer serious consequences and the tooth-specific distributions of cusp fracture should help dentists and patients to make informed decisions regarding preventive restorative intervention prior to fracture.

Adult↗
PubMedDate not supplied

Rapid forced eruption: a case report and review of forced eruption techniques.

This article reviews the infrequently utilized treatment method of forced eruption and how it can serve as an alternative to the sacrifice of the natural root system. Forced eruption can preserve the natural root system and related periodontal architecture, resulting in years of additional service for the patient. It also can maintain adjacent tooth structure while retaining the option for future implant reconstruction. Given the reported success of forced eruption, the technique requires greater attention and increased application among dentists. A case of forced eruption in the anterior maxilla utilizing a removable device is described. An overview of forced eruption technique also is provided.

Adult↗
PubMed2004

Autogenous tooth fragment reattachment--association of periodontal surgery and endodontic and restorative procedures: a case report.

The occurrence of dental traumas in adult patients is on the rise, according to the literature, and require correct and adequate treatment specific to each fracture in order to preserve the remaining tooth. In this article, two different fracture cases are reported. Based upon these cases, it may be concluded that there are situations that require the clinician to have a multidisciplinary vision of the different dental specializations in order to effectively treat the patient.

Adult↗