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PubMedDate not supplied

Phenotypic features of dentition in diastrophic dysplasia.

Diastrophic dysplasia (DTD) is a well-characterized, recessively inherited osteochondrodysplasia. The gene, DTDST, in which mutations are responsible for the disease, codes for a sulphate transporter protein. We studied 53 patients with earlier diagnosed DTD for special characteristics in the oral region. Clinical examination included impressions of dental arches, oral photographs, and panoramic radiographs. Palatal clefting was recorded. Congenitally missing teeth were evaluated and dental maturity calculated from the panoramic radiographs. Tooth crown size and length and breadth of dental arches were measured from the casts. Dental anomalies and orthodontical status were evaluated from the casts and oral photographs. The level of oral hygiene was evaluated with caries (DMF) and periodontal (GBI) indices. Cleft palate was recorded in 56% and hypodontia (excluding third molars) in 31% of the patients. Dental age was retarded. Dental arches were narrow and tooth crown size was reduced. The observed crown size reduction could result from the same factors that cause cleft palate and/or hypodontia, or from a lack of sulfation in the developing dental papilla. The typical malocclusion traits were crowding, lateral crossbite, and open bite, which we assumed to result from reduced growth potential of the dental arches. Despite crowding and limited flexion of the finger joints leading to a severe handicap, the level of oral hygiene was high and no need for auxiliary equipment for cleaning the teeth was noted.

Adolescent↗
PubMed1995

[A case of injured unerupted permanent tooth in a child].

Children with trauma visit frequently the department of oral and maxillofacial surgery. The treatment for injured permanent teeth is different from that for injured deciduous teeth. We have experienced a case of a 9-year-old boy with an injured unerupted immature permanent tooth with tooth crown fracture. When the tooth erupted gradually, fractured pieces were removed three times, and indirect pulp capping was performed. Three years after the injury eruption was almost completed and pulp was alive, even though the dental roentgenograph showed obliteration of the crown pulp cavity.

Child↗
PubMedDate not supplied

An in vitro evaluation of the integrity of stainless steel crown margins cemented with different luting agents.

The elderly population is retaining more teeth which require extensive restorations. The purpose of this study was to identify a luting agent which had the least marginal breakdown when used with stainless steel crowns. Thirty-six caries-free molars were selected, prepared for stainless steel crowns, and embedded in acrylic to support the crown and tooth. The crowns (Unitek/3M) were cemented with 4 different luting agents: (A) Fleck's Cement, (B) Ketac-Cem, (C) All-Bond C & B Cement, and (D) Panavia EX Cement. All the restored teeth were thermocycled and divided into 3 experimental groups. Twelve teeth were stained. The remaining teeth were occlusally loaded and stained. The remaining 12 teeth were thermocycled and stained again. The stainless steel crowns were then sectioned and photographed at 7.5x mag. The dye penetration was evaluated by measurement of the percentage of dye penetration from the crown margin to the cusp tip on each side. Statistical analysis found that the least dye penetration was with All-Bond C & B Cement (p = 0.0001). The most extensive penetration was observed in Ketac-Cem Occlusal loading was a significant factor (p = 0.0001) increasing the dye penetration, but the crown-tooth gap was not.

Aged↗
PubMed2005

Results after replantation of avulsed permanent teeth. I. Endodontic considerations.

Following avulsion and replantation, teeth are at risk for infection and infection related resorption (IRR). Severe discolorations of tooth crowns and cervical root fractures are common. This study presents data on endodontic related complications of avulsed teeth replanted following an extraoral endodontic treatment. Periodontal aspects will be discussed in the second part of the present publication. Twenty-eight permanent teeth in 24 patients aged seven to 17 years were replanted after avulsion. All teeth could be evaluated. In all teeth extraoral endodontic treatment by retrograde insertion of ceramic or titanium posts was performed. Mean observation period was 31.2 months (median: 24.1 months). Nine teeth healed with a functional periodontal ligament (PDL) (functional healing, FH), 19 teeth exhibited replacement resorption (RR), which was succeeded by IRR in three teeth after observation periods of more than 14 months. Diagnosis was set to tunneling resorption (one case) and to cervical resorption preceded by complete RR (two cases). No early IRR was observed. All six teeth rescued in physiologic conditions (cell culture medium of tooth rescue box) exhibited FH. Discolorations of tooth crowns or other complications (cervical root fractures, fractures of posts) were not observed. No differences in the healing results of immature and mature teeth were observed which is in contrast to previous studies. This finding is explained with the different endodontic treatment protocols. Extraoral endodontic treatment by retrograde insertion of posts prevents early IRR and minimizes the overall incidence of IRR. The method does not negatively influence periodontal healing. As there are further advantages (no discoloration, no root fractures, patient not involved, less radiographs, less time consumption, less costs) the method is recommended in isolated teeth before replantation. Especially immature teeth profit from the prevention of complications.

Adolescent↗
PubMed1999

Facial injuries in skiing. A retrospective study of 549 cases.

In the last 2 decades, reports of skiing injuries have shown an increasing number of skiers with severe trauma. This article provides an account of a retrospective study of 549 patients with 1155 facial injuries sustained while skiing who received treatment at the Department of Oral and Maxillofacial Surgery at the University Hospital in Innsbruck, Austria between 1991 and 1996. The study was based on a questionnaire answered by the patients and on case report forms. Most of the patients were male (65.2%) and were aged between 3 and 81 years (average 28.4 years). A simple fall while skiing was the main type of accident (45.9%), followed by collisions with other people (23.5%). Injuries were classified into 1 of 3 groups: (i) lesions of the soft tissue (32.2% of all injuries); (ii) dentoalveolar traumas (24.3%); and (iii) fractures of facial bones (43.5%). Lacerations and haematomas were the most frequent lesions in patients with injuries to the soft tissues. The group of patients with dentoalveolar trauma mainly presented with fractures of tooth crowns. Fractures involving the mandible and the zygomatic bone were predominant in patients in the third group. Concomitant injuries mainly included injuries to the brain and skull fractures. Treatment was ambulatory, or by admission and surgery. We did not observe an increase in the number of skiing accidents causing facial injury in the last 5 years. Facial injuries represented 4% of all skiing injuries, a lower proportion than in other sports.

Accidental Falls↗
PubMed2007

Usefulness of combining clinical and radiological dental findings for a more accurate noninvasive age estimation.

The aim of this study was to establish correlations of clinical and radiological dental findings, alone or in combination, with chronological age in adults. Dental findings and orthopantomograms of 984 patients (aged 20-60 years; 524 females/460 males) were analyzed. DMF-T index and distance (alveolar bone level, ABL) between cemento-enamel junction and alveolar bone margin were recorded. Additionally, clinical and radiological findings at each tooth crown and root were collected according to the actual status of destruction and restoration, and a total score for each dentition (TSD) was calculated. After univariate correlation analysis, correlation coefficients for ABL and TSD were improved by using square root (sqrt). However, the determination accuracy was still not satisfactory; 90% of the residuals were in the range of about +/-10. The present study showed that clinical and radiological dental findings could not be used, not even in combination, for accurate age estimation as a single method, but that they could support other methods.

Adult↗
PubMed1999

Clinical, radiologic, and histopathologic features of invasive cervical resorption.

Invasive cervical resorption is a relatively uncommon form of external root resorption. There may be no external signs, and the resorptive condition is often detected by routine radiographic examination. Where the lesion is visible, the clinical features vary from a small defect at the gingival margin to a pink coronal discoloration of the tooth crown resulting in ultimate cavitation of the overlying enamel. The condition is usually painless unless pulpal or periodontal infection supervenes. Radiographic features of lesions vary from well-delineated to irregularly bordered mottled radiolucencies, and these can be confused with dental caries. A characteristic radiopaque line generally separates the image of the lesion from that of the root canal, because the pulp remains protected by a thin layer of predentin until late in the process. Histopathologically, the lesions contain fibrovascular tissue with resorbing classic cells adjacent to the dentin surface. More advanced lesions display fibro-osseous characteristics with deposition of ectopic bonelike calcifications both within the resorbing tissue and directly on the dentin surface. Secondary invasion of microorganisms into the pulp or periodontal ligament space will elicit a normal inflammatory response.

Adolescent↗
PubMed2003

Diagnosis and management of unusual dental abscesses in children.

Although the majority of dental abscesses in children originate from dental caries or trauma, a few are associated with unusual conditions which challenge diagnosis and management. Recent research findings have shed light on these unusual entities and greatly improved understanding of their clinical implications. These conditions include developmental abnormalities such as dens invaginatus in which there is an invagination of dental tissues into the pulp chamber and dens evaginatus in which a tubercle containing pulp is found on the external surface of a tooth crown. In addition, inherited conditions which show abnormal dentine such as dentine dysplasia, dentinogenesis imperfecta, and osteogenesis imperfecta predispose the dentition to abscess formation. Furthermore, 'spontaneous' dental abscesses are frequently encountered in familial hypophosphataemia, also known as vitamin D-resistant rickets, in which there is hypomineralization of dentine and enlargement of the pulp. In addition to developmental conditions, there are also acquired conditions which may cause unusual dental abscesses. These include pre-eruptive intracoronal resorption which was previously known as 'pre-eruptive caries' or the 'fluoride bomb'. In addition, some undiagnosed infections associated with developing teeth are now thought to be the mandibular infected buccal cysts which originate from infection of the developing dental follicles. In the present paper, these relatively unknown entities which cause unusual abscesses in children are reviewed with the aim of updating the general practitioner in their diagnosis and management.

Abscess↗
PubMed1999

Morphometric variables of the primary second molar in children with Down syndrome.

Thirty-seven second primary molar teeth of children with DS were examined from casts of 6 girls and 8 boys aged 7-14 years, obtained from two centers for DS in Jerusalem and Haifa, Israel. One hundred and eighty-two primary second molars of normal children were examined from dental casts of 26 boys and 21 girls, which were taken for routine orthodontic evaluation. The following variables were examined on the teeth: all the inter-cuspal distances, the angle between the cusps, the area within the line connecting cusp tips, maximal buccolingual and mesiodistal dimensions, maximal perimeter of the occlusal table, maximal area of the occlusal table, maximal perimeter of the tooth crown from occlusal view, and maximal area from occlusal view. The results indicate that the second primary molars in individuals with DS are generally larger in the external dimensions (bl, md) than teeth of normal children, with larger inter-cuspal distances ('internal dimensions'). No significant change in the angles between the cusps were recorded. Thus, it seems that DS second primary molars retain the same cuspal shape of normal teeth, but with larger proportions. Sexual dimorphism was found to be more pronounced in the DS children. It is suggested that in DS, there may be a transitory acceleration in mitotic activity of developing enamel organs at about the early stage of gestation, which persists during the initial stages of mineralization of the primary teeth. The initial acceleration would then be followed by the widely recognized retardation in growth, reflected in smaller permanent teeth.

Adolescent↗
PubMed2004

Root lengths in 47,XYY males' permanent teeth.

Studies on individuals with sex chromosome anomalies have demonstrated the promoting effect of the Y chromosome on tooth crown enamel and dentin growth. The present research investigated permanent tooth root lengths in 47,XYY males. The measurements were made from panoramic radiographs. The results indicate longer tooth roots in 47,XYY males compared with those in control males and females. The promoting effect of the Y chromosome on dental growth thus continues in the form of root dentin after the completion of crown growth. The results, together with those on tooth crown sizes in 47,XYY males, suggest that growth excesses are evident and final, beginning a few months after birth and continuing up to the age of 14 years, at least. The excess root dentin growth in 47,XYY males, as well as sexual dimorphism in the growth of crown and root dentin, might be caused by the same factor on the Y chromosome.

Adolescent↗
PubMed2005

Dental morphology and variation in theropod dinosaurs: implications for the taxonomic identification of isolated teeth.

Isolated theropod teeth are common Mesozoic fossils and would be an important data source for paleoecology biogeography if they could be reliably identified as having come from particular taxa. However, obtaining identifications is confounded by a paucity of easily identifiable characters. Here we discuss a quantitative methodology designed to provide defensible identifications of isolated teeth using Tyrannosaurus as a comparison taxon. We created a standard data set based as much as possible on teeth of known taxonomic affinity against which to compare isolated crowns. Tooth morphology was described using measured variables describing crown length, base length and width, and derived variables related to basal shape, squatness, mesial curve shape, apex location with respect to base, and denticle size. Crown curves were described by fitting the power function Y = a + bX(0.5) to coordinate data collected from lateral-view images of mesial curve profiles. The b value from these analyses provides a measure of curvature. Discriminant analyses compared isolated teeth of various taxonomic affinities against the standard. The analyses classified known Tyrannosaurus teeth with Tyrannosaurus and separated most teeth known not to be Tyrannosaurus from Tyrannosaurus. They had trouble correctly classifying teeth that were very similar to Tyrannosaurus and for which there were few data in the standard. However, the results indicate that expanding the standard should facilitate the identification of numerous types of isolated theropod teeth.

Analysis of Variance↗
PubMed2000

[The management of 126 cases of posterior cracked crown of tooth and its effective observation].

OBJECTIVE: To detect the treatment and effect of posterior cracked tooth. METHODS: 162 posterior cracked teeth of 158 cases, including enamel fissure and dentin fissure, all there cases undergone the synthetical treatment and follow up in different period, the longest observation period was 2.5 years. RESULTS: The healing and improved rate of 162 cracked teeth 90.74%. Among cases of failure, we have founded 6 cases of acute pulpitis (3.7%), 3 cases of alveodental abscess (1.85%), 2 cases of chronic apical periodontitis (1.24%), 4 cases of tooth fracture (2.4%). CONCLUSION: Cracked tooth was caused by multiple factors. Early diagnosis, synthetical treatment, and follow up in different period are 3 main factors in treatment.

English Abstract↗
PubMed1993

Odontometry and biological affinity in south Asia: analysis of three ethnic groups from northwest India.

Current knowledge of odontometric variation among the people of south Asia is limited, yet variation in tooth size has the potential to answer important questions regarding genetic relationships among contemporary social groups. Here, we report tooth crown diameters for 3 ethnic groups (Bhils, Garasias, Rajputs) from Gujarat State and contrast these data with 10 social groups from north, northwestern, northeastern, west-central, and south India. Univariate descriptive and inferential statistics are presented by group and by sex. Examination of crown diameters demonstrates that tooth size differs significantly between social groups in Gujarat. Cluster analysis of sex-standardized odontometric mean parameter values indicates that in apportionment of tooth size throughout the dentition low-status Garasias are slightly more similar to tribal Bhils than they are to high-status Rajputs. Principal components analysis by sex identifies three components that together account for 58.2% and 56.3% of the total variance among Gujarati females and males, respectively. These components are identified as overall size, a dimensional contrast between mesiodistal diameters and buccolingual diameters, and a dimensional contrast between mesiodistal diameters and buccolingual diameters among anterior teeth coupled with a contrast between anterior teeth (incisors, canines) and posterior teeth (premolars, molars). Ordination of group component scores indicates that (1) males and females of each social group exhibit a pattern of tooth size apportionment most similar to the opposite member of that same social group and (2) low-status Garasias exhibit a tooth size apportionment profile intermediate between tribal Bhils and high-status Rajputs. To place this pattern of odontometric variation among modern Gujaratis in larger perspective, data from Gujarati males were contrasted against males from 10 social groups from north, northwestern, northeastern, west-central, and south India. Cluster analysis of group-standardized odontometric mean parameter values indicates that (1) Gujarati social groups, regardless of social status or caste adherence, are more similar to one another than to any other group included in this analysis and (2) Gujarati social groups share closet affinities with geographically proximate social groups (Ahirs, Jats, Kunbis). Principal components analysis yields three components that combine to explain 64.0% of the total variance. These components are interpreted as a dimensional contrast among posterior teeth, a dimensional contrast among nonmolar teeth, and a contrast between anterior and posterior teeth. Ordination of group component scores indicates that tribal Bhils possess tooth size apportionment profiles that are different from other Indian tribal groups but are proximate to those found among Gujarati Hindu groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed2004

Materials-induced variation in the torque expression of preadjusted appliances.

The purpose of this article is to comprehensively investigate the sources of variation in the expression of torque in preadjusted appliances. Variables related to properties of materials were systematically analyzed, including (1) the inability to fill the slot because of the size difference of archwires and bracket slot, (2) irregularities from the manufacturing process of brackets precluding proper engagement, (3) differences in the stiffness of wire alloys engaged to the bracket slot, (4) variations between actual and reported bracket torque values, and (5) ligation modes, all of which might account for increased third-order clearance or bracket-archwire "play." The effect of these variations on the expression of torque is discussed, and the net buccolingual inclinations are provided as a function of wire size and composition for common bracket slot-archwire combinations. Most reports published on this issue indicate a loss of torque control as high as 100% of the prescribed value. Furthermore, the fallacy of transferring the ideal crown inclination to the torque prescribed in the bracket is illustrated, along with the underestimation of the prescribed torque relative to the proper tooth crown. The realistically required torque is analyzed to its constituent components, involving tooth inclination, compensation for the slot-wire play, and incomplete ligation with elastomeric ligatures. Based on the evidence available, it is proposed that a high-torque prescription should be selected to account for the lack of full expression of the prescribed torque that occurs clinically.

Dental Alloys↗