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Drawings and photographs of shape, symmetry, and proportion of maxillary central incisors were evaluated by 112 dentists, 215 dental sutdents, 399 male patients, and 695 female patients. A significant difference was found between the evaluations of patients and dentists; the preferences of dental student; were between those of patients and dentists. Male and female patients had similar opinions.
A total of 22 cases that were diagnosed as having space discrepancy problems in the deciduous and early mixed dentitions showed that treatment by early expansion therapy with Crozat appliances had eliminated the need for extraction of deciduous canines or permanent premolars.
Ten mandibular first molars were hemisected and the root surface of each root was measured using stereophotogrammetry and computer analysis. In each tooth the mesial root was determined to have a greater surface area than the distal root. This difference was statistically significant. The fact that the mesial root has the larger surface area must be a consideration when hemisection is planned.
The purpose of this study was to develop, with simple linear regression analysis, equations that could accurately predict the mesiodistal widths of unerupted canines and premolars in both arches of the mixed dentition patient. Clinically useful prediction equations were developed and tested on a sample of orthodontic patients. Performance of the equations in patients was satisfactory. Charts and suggestions for completing a tooth size-arch length analysis in the patient with a mixed dentition were discussed.
Digital images produced by direct sensor systems are much larger than conventional radiographic film images because of monitor resolution and digital image file sizes. This difference in size may introduce difficulties when estimating distances (for example, during endodontic treatment). The aim of this study was to compare observers' estimates of distances on digital images with those of conventional radiographs.
BACKGROUND: Maxillary midline diastemas are a common esthetic problem that dentists must treat. Many innovative therapies have been used, varying from restorative procedures to surgery (frenectomies) and orthodontics. At times, these procedures have been performed by the dentist without full appreciation of the factors contributing to the diastemas. CASE DESCRIPTION: Before the practitioner can determine the optimal treatment, he or she must consider the contributing factors. These include normal growth and development, tooth-size discrepancies, excessive incisor vertical overlap of different causes, mesiodistal and labiolingual incisor angulation, generalized spacing and pathological conditions. A carefully developed differential diagnosis allows the practitioner to choose the most effective orthodontic and/or restorative treatment. CLINICAL IMPLICATIONS: The differential diagnosis leads to a treatment approach that most effectively addresses the patient's problem. By treating the cause of the diastema, rather than just the space, the dentist enhances both the patient's dental function and appearance.
BACKGROUND: According to the Third National Health and Nutrition Examination Survey, crowding and irregularity remain a consistent problem for children. Management of space problems continues to play an important role in a dental practice. It also represents an area of major interaction between the primary provider and the specialists. This article attempts to update clinicians on the current knowledge of space management. DESCRIPTION OF CONDITION: Proper management of space in the primary and mixed dentitions can prevent unnecessary loss in arch length. Diagnosing and treating space problems requires an understanding of the etiology of crowding and the development of the dentition to render treatment for the mild, moderate and severe crowding cases. Most crowding problems with less than 4.5 millimeters can be resolved through preservation of the leeway space, regaining space or limited expansion in the late mixed dentition. In cases with 5 to 9 mm of crowding, some can be approached with expansion after thorough diagnosis and treatment planning. Most of these cases will require extraction of permanent teeth to preserve facial esthetics and the integrity of the supporting soft tissue. Serial extraction or guidance of eruption is reserved for treatment of severe tooth-size/arch-size discrepancies. Due to variations in the timing and extraction sequence depending on the diagnosis, serial extraction should be reserved for those who can complete the treatment successfully. CLINICAL IMPLICATIONS: The recommended timing of referring patients with moderate crowding to specialists for treatment is in the late mixed-dentition stage of development. Patients with severe crowding will require earlier evaluation for serial extraction.
The present investigation was designed to study the distance from the 3 bifurcation entrances to their opposite roots, and also the virtual center of the trifurcation (TC), which is equidistant from each bifurcation entrance, of maxillary molars. Thirty-five teeth devoid of any surface damage or fused roots were selected. Roots were included in acrylic resin and cross-sectioned at the cementoenamel junction to the apex using a rotary diamond blade and 0.45-mm slices were obtained. A profile projector apparatus was used to obtain the coordinated points on a Cartesian plane, which allowed the calculation of all distances present using analytic geometric formulas. Based on statistical analysis (comparison by Kruskal-Wallis ANOVA test, p<0.05), the following results were obtained: 1) mean distance from the buccal furcation reaching the palatal root was 6.72 +/- 0.99 mm (range 4.73-8.67 mm); 2) mean distance from the mesial and distal furcations to the distal and mesial roots were 5.42 +/- 0.83 mm (range 3.78-7.07 mm) and 5.90 +/- 0.87 mm (range 4.18-7.59 mm), respectively. All means were determined up to the point of 1.40 mm from each bifurcation opening; 3) mean distance of TC was 4.26 +/- 0.42 mm (range 3.44-5.08 mm) for all levels.
The purpose of this report is to present educational material that would allow the dental student to learn to easily identify the morphologic characteristics of permanent teeth, and how they fit together (occlusion). In order to do this, macro models of permanent teeth with no attrition were carved in wax and later molded with alginate. These molds were filled with plaster, dental stone and/or cold-cured acrylic resin. The large individual dental stone tooth models were mounted on a wax base, thus obtaining maxillary and mandibular arches which were occluded. These dental arches were molded with plaster or dental stone. The authors suggest that these types of macro models allow an excellent visualization of the morphologic characteristics of permanent teeth and occlusion. Dental students are able to carve the permanent dentition in wax with great facility when they can observe macro models.
A high rate of root exposure and consequently the exposure of the furcation area is usually observed in multirooted teeth. In maxillary molar teeth, this fact may endanger the three existent furcations (buccal, mesial and distal), causing serious problems. In this research, distance measures from the buccal furcation to the mesial (F1M) and distal (F1D) surfaces of the mesio-buccal and disto-buccal roots; from the mesial furcation to the buccal (F2B) and palatal (F2P) surfaces of the mesio-buccal and palatal roots and from the distal furcation to the buccal (F3B) and palatal (F3P) surfaces of the disto-buccal and palatal roots, respectively were established. One hundred maxillary first molar teeth were used, 50 of the right and 50 of the left side. Reference marks and demarcations were determined on the furcations and also on the root surfaces involved in the measures. We concluded that these measurements are important because they may effectivelly contribute to diagnosis, prevention and treatment of periodontal problems.
OBJECTIVE: The aim of this study was to examine the relationship between dental maturation and somatic development and to discover their possible deviations in children with shunt-treated hydrocephalus. DESIGN: Radiographs (orthopantomogram and hand-wrist radiograph) from children with shunt-treated hydrocephalus were analyzed with respect to the dental maturation and compared with values of an age- and sex-matched control group and population standards. PATIENTS: Forty-one children with shunt-treated hydrocephalus (27 boys and 14 girls) aged from 5 to 16 years (median age 11.0 years). RESULTS: The mean deviation of dental age from chronological age was significantly greater in the hydrocephalic group than in the control group. The mean value of dental age deviation was advanced in early pubertal stages but reduced in later pubertal stages. CONCLUSIONS: These findings can be explained by changes in the endocrinological conditions, which are due to disturbed pituitary secretion. The present results could also partly reflect an adaptable developmental pathway in an otherwise strictly genetically determined process.
OBJECTIVE: Oculo-facio-cardio-dental (OFCD) syndrome is a rare condition with ocular, facial, cardiac, and dental disorders. The purpose of this report is to describe three Japanese female patients by using facial measurements, tooth measurements, and cephalometric analysis. DESIGN: Facial measurements, tooth measurements, and the results of cephalometric analyses were compared with Japanese standards using panoramic roentgenograms, dental casts, and lateral cephalograms. RESULTS: A long face and thick upper and lower lips were noted for all cases from facial measurements, and a long crown length and long dental root were noted for all cases from tooth measurements. Relative mandibular protrusion and a large anterior lower facial height, accompanied by a steep mandible and large gonial angle, were seen from the cephalometric analyses. CONCLUSIONS: The results of a long face and long dental root were in accordance with previous reports. In addition, thick upper and lower lips, relative mandibular protrusion, large anterior lower facial height accompanied by a steep mandible, and a large gonial angle may be characterized as specific features of this syndrome.
OBJECTIVE: To quantitatively compare the alveolar bone support ratio of the permanent canine in cleft patients who received secondary alveolar bone graft with that of the population without clefts. DESIGN: Retrospective study utilizing periapical radiographs of the subjects with and without clefts. SETTING: Hospital and university based. PATIENTS: Eighteen unilateral and 9 bilateral cleft patients who had secondary bone graft procedures. MAIN OUTCOME MEASURES: Alveolar bone support of the permanent canine utilizing the ratio of bone height to root length. RESULTS: Average bone support for the permanent canine was 88.55% in patients with clefts and 95.59% in patients with no history of clefts. This difference was statistically significant. There was no statistically significant difference in alveolar bone support ratio between the unilateral and bilateral cleft patients. CONCLUSIONS: Although alveolar bone support was significantly higher in the noncleft control group, a successful level of alveolar bone support was achieved for the permanent canine on the cleft site after secondary bone graft. There was no difference in alveolar bone support achieved for the permanent canine whether the type of the cleft was unilateral or bilateral.
The maxillary arch-form of 41 Sri Lankan adults with unoperated complete unilateral cleft lip and palate (8 female and 33 male) were compared to a control group of 100 normal Sri Lankan adults (45 female and 55 male). The teeth in the cleft group were smaller than their equivalents in the control group, the most marked difference being found in the central and lateral incisors. Arch widths of the cleft groups were reduced, more anteriorly than posteriorly, resulting in more V-shaped arches. No differences were found in the arch length or chord lengths between the groups. Crossbites occurred in 19.5 percent of the cleft group as compared to none of the controls. The overjet was greater in the cleft group than in the controls. A higher percentage of missing teeth was recorded in the cleft group.
As a pilot study, dental casts of 30 patients with unilateral cleft lip and palate were selected and examined from the longitudinal data in the Department of Orthodontics, Kyushu University Dental Hospital. Dental casts of the anterior teeth were sectioned at right angles to the long axis of the tooth 2 to 3 mm below the incisal edge. The teeth were differentiated according to their cross sections. They were classed as lateral incisors or other types by the ratio of labiolingual diameter to mesiodistal diameter and the flatness labiolingually. Dental casts of 309 additional patients with cleft alveolus were examined subjectively based on above findings. In primary dentition, 183 of 184 teeth on the cleft side were incisal type. One tooth was canine type. In permanent dentition, 42 of 78 teeth on the cleft side were conical type, 20 teeth were intermediate type, and 16 teeth were incisal type. As a conclusion, the tooth on the cleft side is almost certain to be a lateral incisor, not a supernumerary canine tooth. As well, their form was normal in the majority of the primary dentition, but malformed in the permanent one.
Maxillary lateral incisors on the alveolar cleft were investigated in 431 cleft children registered in the Department of Orthodontics, Kyushu University Dental Hospital. The majority of primary maxillary lateral incisors were located on the distal side of the alveolar cleft in both unilateral cleft lip and alveolus (UCLA) and unilateral cleft lip and palate (UCLP) subjects. Permanent teeth in UCLA tend to be located distally, but in UCLP they tend to be congenitally absent (p less than .01). The majority of primary teeth had normal shapes; the majority of permanent teeth were of intermediate type or were missing congenitally. One third of the UCLA and one half of the UCLP subjects who had primary maxillary lateral incisors were not followed by permanent replacements. The location of the majority of permanent maxillary lateral incisors tallied with that of the primary ones except in four UCLA, ten UCLP, and two bilateral cleft lip and palate (BCLP) subjects. Four UCLA and ten UCLP subjects who had primary lateral incisors on the distal side were followed by their permanent successors on the mesial side. Three UCLP and one BCLP subjects had permanent maxillary lateral incisors even though they had no temporary predecessors.
The study models of a group of adult Sri Lankan patients with clefts of the secondary palate were investigated. Tooth-size and arch-dimension comparisons were made with a comparable control group. Significant differences were found between the cleft and control groups in tooth sizes, chord lengths, and arch widths. The cleft group dimensions were generally smaller than those of the control group. Overjets were larger in the cleft group.
To understand the etiology of maxillary hypoplasia better, which is common in individuals with cleft palate and other craniofacial anomalies, the relative growth and contribution of the maxillary and palatine segments to enlargement of the hard palate was examined in rhesus monkeys. The purpose of the study was to identify and evaluate sites of differential growth of the palatine and maxillary segments as they contribute to the development of the midface and facial prognathism. One hundred and eight male and 107 female skulls ranging from 1.0 to 7.0 years of age were examined. Measurements of the maxillary and palatine lengths, palatal width, midface depth, canine length, and molar surface areas in the ontogenetic sample were collected. Univariate and bivariate statistics were used to describe dimensional changes and evaluate region-specific sex differences. The relative growth of palatal dimensions was evaluated using allometric analysis methods. Significant sex differences were observed (t-test, p < or = .05) for all palatal dimensions by 4 years of age. However, proportions of the maxillary and palatine segments to overall palate length appeared to be similar throughout growth for both sexes. The results suggest that sutures of the midface, in particular the transverse palatine suture, may be important in the bony development of the palate during growth. These sutures may contribute to the overall modulation of palatal development.(ABSTRACT TRUNCATED AT 250 WORDS)