Radiographic Assessment of Dental Maturation in Children With Dental Agenesis.

BACKGROUND: Dental agenesis is the most common developmental anomaly in humans, frequently associated with disorders in dental development and maturation. AIM: The purpose of this study is to determine radiographic variations in dental maturation in a group of Venezuelan children with dental agenesis. STUDY DESIGN: 1,188 panoramic radiographs, from healthy patients ages 5 to 12 years old were studied for agenesis of permanent teeth. Dental maturation was assessed by relative eruption and dental age according to Nolla, comparing children affected with dental agenesis to a stratified control group selected from the same population, excluding children with premature loss of primary teeth in the left quadrants and unclear radiographs. Descriptive analysis, and differences between means and medians (Student t test, Kruskall-Wallis p=0.05) were performed. RESULTS: Medians for Nolla stages were similar between groups, with delay in tooth formation in the agenesis group for second molars (p<0.05) and maxillary lateral incisors and second premolars. Dental age was significantly underestimated for both groups, -0.89 (±0.78) for the control group and -1.20 (±0.95) for the study group. Tooth eruption was similar between groups. CONCLUSION: Dental age was significantly delayed in Venezuelan children with dental agenesis, with variable significance for tooth formation of studied teeth.

Cost-Effective Management of Patients with Unilateral Congenitally Missing Second Maxillary Premolars.

Two case presentations are utilized to review the cost-effective treatment options in patients with unilateral congenitally missing second maxillary premolars. Once diagnosed, the dentist can either preserve or remove the respective primary molar. Preservation will lead to a tooth-size discrepancy. To limit the size of the second primary molar to the dimension of the contralateralpremolar, and to allow the preservation of alveolar bone, removal of its mesio-distal aspect should be performed. Later on, the primary molar may become infraoccluded or lost, and it will be necessary to do a coronal built-up or a prosthetic replacement respectively. Any type ofprosthetic replacement will significantly increase the total cost of treatment. Clinicians should aim for ideal occlusion and profile and take into account other orthodontic problems and propose the most appropriate treatment plan for each patient.

Valoración de la ecuación de Tanaka-Johnston en estudiantes cubanos con oclusión normal / Assessment of Tanaka-Johnston equation in Cuban students presenting normal occlusion

El análisis de Tanaka-Johnston, mundialmente empleado para la predicción del espacio de caninos y premolares no brotados, ha sido muy cuestionado por la variabilidad en el tamaño dentario entre las diferentes poblaciones, y por haber sido realizado en un grupo étnico no aplicable a todos. Se realizó un estudio descriptivo transversal, con el objetivo de determinar el ancho mesiodistal de incisivos, caninos y premolares mandibulares, así como de caninos y premolares maxilares, y comparar la suma real de estos dientes con los estimados por Tanaka-Johnston, según el sexo y la arcada. El universo de esta investigación estuvo constituido por 50 estudiantes de la Facultad de Estomatología de La Habana, 25 del sexo femenino y 25 del sexo masculino, con oclusión normal, sin antecedentes de tratamiento ortodóncico; todos descendientes de cubanos. En los resultados se observó que los anchos mesiodistales de los incisivos, caninos y primeros premolares inferiores y de caninos y segundo premolar izquierdo superiores fueron significativamente mayores en el sexo masculino que en el femenino. La suma real de caninos y premolares superiores e inferiores fue mayor en el sexo masculino que en el femenino. Cuando se comparó la suma real de caninos y premolares, con lo estimado según la ecuación de Tanaka-Johnston, se halló que la esta sobrestimó los valores de caninos y premolares, ya que los resultados fueron significativamente menores(AU)

The Tanaka-Johnston analysis used at worldwide to predict the space of non-erupted canines and premolars has been questioned due to the variability in the teeth size among different populations and also to be carried out in non-applicable whole ethnic group. A cross-sectional and descriptive study was conducted to determine the mesiodistal width of mandibular incisives, canines and premolars, as well as of danines and premolar-maxillary and to compare the real sum of these theeth with the estimates by Tanaka-Johnston, according to sex and the arcade. Universe of this research included 50 students of Stomatology Faculty of havana (25 males and 25 females) presenting with normal occlusion, without a history of Orthodontics treatment all of them descendants of Cubans. In results it was noted that the mesiodistal widths of incisives, canines and first lower premolars and of canines and second left premolars upper are greater in male sex than in the female one. The real sum of upper and lower canines and premolars was greter in male sex than in the female one. Comparing the real sum of canines and premolars with that estimated according Tanaka-Johnston, it was noted that it overestimated the values of canines and premolar since the results were significantly lower(AU)

The orthodontic-restorative interface: 2. Compensating for variations in tooth number and shape.

UNLABELLED: The aim of this second article in this series of two is to outline a variety of methods which may be used to compensate for variations in tooth shape and number using a combination of orthodontic and restorative approaches. It will also provide an overview of other areas of patient care which necessitate a multi-disciplinary orthodontic/restorative approach. The article will highlight the importance of combined planning from the outset and the close relationship between the different specialties, which must be maintained throughout treatment. The methods of compensating for variations in tooth number and shape will often require contributions from both orthodontist and restorative dentist. It is important that both disciplines are involved in the assessment and treatment planning process so that they know what will be expected of them during the patient's care. Treatment planning in isolation may lead to care being delivered which is below the optimum standard which can be achieved. The orthodontist and restorative dentist are likely to liaise with the patient's general dental practitioner so that he/she can provide the restorative treatment in some cases. CLINICAL RELEVANCE: Great improvements in aesthetics and function may be obtained using an interdisciplinary approach for patients who have variations in tooth number and shape.

Radiographic assessment of congenitally missing teeth in orthodontic patients.

OBJECTIVE: To estimate the prevalence of congenitally missing teeth (CMT) in patients evaluated for orthodontic care. A sample of 668 panoramic radiographs from Mexican population was reviewed from orthodontic healthy patients, 9-20 years old. METHOD: Statistical tests were used to compare maxillary and mandibular hypodontia in right and left quadrants between males and females. RESULTS: Prevalence was 27% when all teeth were included, and was 2.7% when third molars were excluded. A significant difference was found between maxillary and mandibular symmetrical CMT in third maxillary molars, lateral incisors and second premolars (P < 0.001), and in mandibular third molars and central incisors (P < 0.001). CONCLUSIONS: We confirmed that occurrence of CMT in the permanent dentition of a Mexican population most often affects third molars, followed by maxillary lateral incisors and then mandibular second premolars.

Hypodontia in 9-year-old Norwegians related to need of orthodontic treatment.

The present study reports on the prevalence of hypodontia in a Norwegian population and classifies children with hypodontia according to need of orthodontic treatment. Orthopantomograms of 1953 children (960 girls and 993 boys) at the age of 9 were available for examination. Of the boys registered with hypodontia of second premolars at the age of 9, 11.3% showed late mineralization between the ages of 9 and 12. Only 2.9% of the girls showed late mineralization. The corrected prevalence of hypodontia, excluding third molars, in the girls was 7.2%, in the boys 5.8%, and in both sexes combined 6.5%, the difference between sexes not being statistically significant. Of the children with hypodontia, 86.6% lacked only one or two permanent teeth. The most frequently missing teeth were the mandibular second premolars, the maxillary second premolars, and the maxillary lateral incisors, in that order. Classification of children with hypodontia according to need of orthodontic treatment showed that about two-thirds had hypodontia only of single posterior teeth with a moderate need of treatment. About one-third had hypodontia involving anterior teeth, and only 3.1% had hypodontia of two or more teeth in the same quadrant with a great need of treatment.