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PubMedDate not supplied

Effect of fractured or sectioned fragments on the fracture strength of different reattachment techniques.

This study evaluated the effect of fractured or sectioned fragments on the fracture strength recovery of four techniques used for reattachment and resin composite buildups. Ninety-one sound, permanent lower central incisors were used. Half the teeth were fractured in the incisal-proximal edge; the other half had the incisal-proximal edge sectioned by a diamond saw. Teeth from each half were randomly divided into five techniques: 1) bonded only; 2) chamfer; 3) over-contour; 4) internal dentinal groove and 5) resin composite buildup. An adhesive system and dual cure resin cement were employed for the reattachment. Restored teeth were subjected to load in a specific point on the buccal surface. Based on the fracture strength of sound teeth, a fracture strength recovery was calculated for each tooth. A one-way ANOVA and Tukey's test (alpha=0.05) were used to evaluate differences between the techniques for each method of obtaining fragments. The fracture strength recovery of similar techniques was evaluated by a Student t-test (alpha=0.05). No differences could be detected among reattachment techniques when fragments were obtained by sectioning. In groups where the fragments were fractured, Techniques 3 and 4 showed the highest fracture strength recovery. The resin composite buildup provided fracture strength recovery similar to intact teeth regardless the way fragments were obtained.

Analysis of Variance↗
PubMed2004

Comparison of diagnostic yields of clinical and radiographic caries examinations in children of different age.

AIM: This was to investigate if the pattern of distribution of caries lesions detected by clinical and radiographic examinations at different diagnostic thresholds changed over a 3-year period during the course of eruption of the permanent dentition. It has been hypothesized that the contribution of bitewing radiography to caries detection in posterior teeth may increase when approximal contacts are established during maturation of the dentition. METHODS: Clinical and radiographic caries recordings were made using the non- cavitated/enamel and cavity/dentine thresholds for caries detection among a group of 12-year-old Lithuanian children with a high caries experience. Examinations were repeated in the same children after 3 years. The bitewing radiographs from both examination sessions were coded to ensure unbiased recordings and were read by a single examiner. RESULTS: The diagnostic yields of the clinical and radiographic examination methods did not change after the permanent teeth had fully erupted. At both examination sessions the clinical examination resulted in the detection of significantly more lesions than did the radiographic method at the non-cavitated level (43- 47% lesions detected by clinical means only and 2-26% by radiographic means only). Only for approximal surfaces at the cavity/dentine diagnostic threshold did radiographs contribute to more lesions (15-16% lesions detected by clinical means only and 38-41% by radiographic means only). Establishment of approximal contacts in the permanent dentition did not increase the relative diagnostic yields of bite-wing radiography in this study group. CONCLUSION: The contribution of the two methods to caries diagnosis depends more on the diagnostic threshold selected than on the stage of maturation of the dentition.

Child↗
PubMed2004

Effect of three direct restorative materials on molar cuspal fracture resistance.

PURPOSE: This study compared the cusp fracture strength of molars restored using a condensable resin composite with that of teeth restored with conventional amalgam, a bonded amalgam, and an incrementally placed resin composite. METHODS: Standardized MOD cavity preparations (2/3 the buccal-lingual dimension x 4 mm deep) were made in 50 extracted human molars and restored as follows (n = 10): (1) a packable posterior resin composite; (2) an incrementally placed microfilled posterior resin composite; (3) a spherical particle amalgam alloy; (4) spherical amalgam with a dentin adhesive liner and (5) no restoration (preparation only; negative control). A sixth group of intact molars (n = 10) served as a positive control. Following storage and thermocycling, each specimen was tested for cuspal fracture strength. RESULTS: Cavity preparation reduced cuspal fracture strength by over 50%. The fracture strength of intact teeth was significantly greater than that of all other groups (P< 0.0001). None of the restorative procedures increased cuspal fracture resistance over that of prepared teeth.

Acid Etching, Dental↗
PubMed2004

Effects of bonded composites vs. amalgam on resistance to cuspal deflection for endodontically-treated premolar teeth.

PURPOSE: To determine, by means of a non-destructive experimental procedure, the extent to which tooth cusps are weakened by endodontic procedures and the effectiveness of adhesive bonding restoration in reducing cuspal deflection as a function of different restorative procedures. METHODS: A mechanically controlled loading device induced cuspal deflection by axial force (range 98-294 N) on an occlusal surface while LTS laser twin sensors registered the amount of deflection. Cusp deflection values, in microns, were recorded for each tooth. Thirty sound maxillary premolars teeth were sequentially evaluated in the following conditions: A) intact tooth; B) completion of endodontic and restorative procedures. Teeth were randomly divided into five groups and restored respectively with: A) amalgam (Dispersalloy); B) Spectrum TPH; C) Surefil; D) Esthet-X; E) Esthet-X + Dyract Flow. RESULTS: The average loading force needed to induce 1 microm cusp deflection was evaluated, for all groups, in intact teeth (range 49.52-58.76 N/microm) and in restored teeth (range 8.56 - 47.05 N/microm). Statistical analysis (ANOVA for repeated measures) has been performed. Mean structural recovery values after restorative treatment were 17% with amalgam, 60% with Spectrum TPH, 59% with SureFil, 54% with Esthet-X, and 99% with Esthet-X/Dyract.

Adolescent↗
PubMed2004

Reattachment of fractured fragments of maxillary central incisors--report of a case.

Reattachment of the original tooth fragment to the fractured tooth helps in maintaining the tooth's colour, wear resistance, morphology and translucency in the restoration. This paper describes the reattachment of fractured fragments using metallic post and core in case of a 12 year old patients who suffered a complicated facture of maxillary central incisors.

Cementation↗
PubMedDate not supplied

Pre-eruptive intracoronal radiolucent defect: a case of a nonprogressive lesion.

Pre-eruptive intracoronal resorption or defect is an unusual radiolucency located in the dentin, just beneath the dentin-enamel junction of unerupted teeth. The pathogenesis of the phenomenon is unclear. The present case with a radiolucency that has not changed in its dimension over a period of almost 7 years, until tooth eruption, raises a question about the progressive nature of the defect that is defined as "resorption." Resorption may not be the sole explanation for a pre-eruptive intracoronal radiolucent defect. The authors also challenge the hypothesis of "local pressure" as a prime cause for the defect. The authors conclude that, when dealing with pre-eruptive intracoronal radiolucency in permanent teeth, a conservative approach with radiographic follow-up is the recommended treatment if the lesion does not seem to endanger the pulp. Intervention can be postponed until after tooth eruption when treatment does not require surgical intervention.

Child↗
PubMed2004

The role of digital volume tomography in the imaging of impacted teeth.

AIM: Digital volume tomography is presented here as an alternative to routine computerized tomography in the diagnosis and treatment planning of impacted teeth. MATERIAL AND METHODS: A sample of 20 patients with a variety of types of tooth impaction was investigated and five representative cases are described. The potential disadvantages of digital volume tomography--inferior spatial resolution of subtle structures and limited representation of soft tissues--were of no clinical significance in the presented cases of impacted teeth. The method provides 3-dimensional images closely akin to regular computerized tomography imaging, yet the amount of radiation produced is less than one sixth that for regular computer tomography and its cost is considerably less. RESULTS AND CONCLUSION: There is reason to recommend the routine adoption of digital volume tomography imaging for positional diagnosis in most cases of impaction of teeth that are candidates for orthodontic resolution.

Child↗
PubMed2003

Consistency and conformity in caries assessment among dental nurses in Anguilla, British West Indies.

PURPOSE: In Anguilla, dental nurses are responsible for providing oral healthcare for children until they reach 18 years of age. This study determined the diagnostic conformity and consistency in caries assessment among dental nurses trained to carry out an oral health survey of 6, 12 and 15-year-old schoolchildren. MATERIALS AND METHODS: Following training in caries diagnosis using slides, extracted teeth and visual-tactile examination, three dental nurses were calibrated by a benchmark examiner (BE) using modified WHO criteria. Conformity and consistency were assessed on four different occasions--on extracted teeth (T0) and in three different groups of children (at C0, D1 and D2) for subject (SB), tooth (TH) and surface (SF) using Kappa statistics. RESULTS: Perfect agreement (kappa score of 1.0) was attained for all sound, decayed and filled lingual and buccal surfaces at D1 and D2 respectively. Levels of conformity (with and without BE) and consistency increased as the survey progressed. Accuracy level ranges for SB, TH and SF were .770-.935(T0), .895-.951(C0), .947-.989(D1) and .985-.993(D2) respectively. Kappa score of 1.0 was obtained by all three examiners for SB, TH and SF at D2. Identical accuracy levels were attained by all examiners for TH (.985) and SF (.993) at D2. Reliability levels for SB, TH and SF ranged from .972-.999(C0), .977-.996(D1) and was 1.0 at D2. CONCLUSIONS: Substantial and almost perfect inter and intraexaminer agreements were attained at calibration, and maintained throughout the survey. Dental nurses in Anguilla can conduct valid and reliable child oral health surveys when adequate and appropriate training is provided.

Adolescent↗
PubMed2004

Effectiveness of a three-headed toothbrush in pre-school children.

PURPOSE: The aim of the study was to compare the effectiveness in plaque removal of a three-headed toothbrush with a conventional toothbrush in pre-school children. MATERIALS AND METHODS: Twenty-nine children (aged 4-5 years) participated in this study. Fourteen children (group A) used a three-headed toothbrush, and 15 children (group B) used a conventional toothbrush for 3 months. At the initial visit, the children brushed their teeth with their regular toothbrush, and at the final visit with the type of toothbrush they had used for the past 3 months. Plaque was recorded at 48 surfaces (molars: vestibular, oral, occlusal; front teeth: vestibular, oral). Plaque reduction was assessed on anterior and posterior areas of the dentition, and on the different tooth surfaces in sextants (I = 55/54; II = 53/63; III = 64/65; IV = 74/75; V = 73/83; VI = 84/85). Statistical evaluation was performed using Wilcoxon signed rank and Mann-Whitney tests. RESULTS: In group A, the median number of surfaces with plaque was reduced significantly after 3 months (p < 0.05). At final examination the number of surfaces with plaque in both groups differed significantly (p < 0.05). Significant decreases in plaque scores were recorded at maxillary and mandibular posterior and mandibular anterior teeth in group A (p < 0.05). The comparison of changes in plaque scores of both groups showed significant differences (p < 0.05) on the occlusal surfaces of molars, except in sextant IV. Significant differences between the groups were also noted on all surfaces of the left side and on the occlusal surfaces of the right side of the mouth (p < 0.05). CONCLUSIONS: This study indicates that the three-headed toothbrush could be an alternative to the conventional toothbrush.

Amines↗
PubMed2004

Mixed dentition analysis in a Moroccan population.

The aims of this study were to produce odontometric data for a Moroccan population, to test Tanaka and Johnston and Moyers methods, to derive regression equations and elaborate a specific orthodontic prediction table for Moroccan children. 50 dental casts of Moroccan students (25 males, 25 females, mean age 22.6 years sd 1.35) were used to perform measurements of the greatest mesiodistal widths of all mandibular and maxillary canines and premolars and mandibular incisors with an orthodontic calliper. Significant sexual dimorphism was found in tooth sizes (p = .001). The study revealed close relationships between the total mesiodistal widths of the mandibular permanent incisors and that of the maxillary and mandibular canines and premolars. The correlation coefficients (r) and the coefficient of determination (R2) were better sexes combined for the maxilla (r = 0.60 ; R2 = 0.36 ) and for the mandible (r = 0.61 ; R2= 0.37). The regression equations elaborated for males and females were used as a basis for establishing an orthodontic prediction table for Moroccan children.

Adult↗
PubMed2004

Distant consequences of traumatic injuries to deciduous teeth--a case report.

The ever increasing number of injuries to deciduous teeth in children constitutes a serious problem in paedodontics. Among many factors that facilitate tooth injuries are malocclusions, and most specifically protrusions of upper incisors of Class II/1 according to Angle. This is a case report of a 6-year-old girl with irregularities of upper permanent incisors due to traumatic injuries to deciduous teeth. In view of the ongoing child development processes, medical check-ups following injuries to deciduous teeth should be undertaken once every two or three months. Since such injuries have an impact on the development of the masticatory organ, children should undergo medical inspection and observation immediately upon the completion of relevant post-trauma treatment.

Child↗