Tooth anomalies associated with failure of eruption of first and second permanent molars

The occurrence of tooth anomalies in association with failure of the first and second molars to erupt was assessed in a sample of 1520 nonsyndromic subjects with uncrowded dental arches (mean age, 14 years 4 months) and compared with the prevalence rate calculated in a matched control group of 1000 subjects. The tooth anomalies examined included infraocclusion of deciduous molars, palatal displacement of maxillary canines, rotation of maxillary lateral incisors, aplasia of second premolars, and small size of maxillary lateral incisors. Associations among arrested eruption of first and second permanent molars and anomalies in tooth eruption and position (infraoccluded deciduous molars, palatally displaced canines, rotated maxillary lateral incisors) were highly significant (P <. 001). No significant association was found among the occurrence of molar eruption disturbances, aplasia of premolars, and small-sized laterals. These findings point to a common biologic cause for the appearance of failure of eruption of molar teeth and other disturbances in tooth eruption and position, most likely under genetic influence.     

Comparison of craniofacial morphology in patients with bilateral complete cleft of primary versus secondary palate.

OBJECTIVE: To identify and compare the craniofacial morphology of patients with bilateral complete cleft of primary palate (BCCPP) and bilateral complete cleft of secondary palate (BCCSP). In addition, to evaluate the differential effects of lip repair and palatal repair on the craniofacial morphology in cleft patients. SUBJECTS: Twenty-four children, 10 boys and 14 girls, mean age of 5.8 years, with BCCPP (BCCPP group). Twenty-five children, 10 boys and 15 girls, mean age of 5.6 years, with BCCSP (BCCSP group). Design: Retrospective analysis. MAIN OUTCOME MEASURES: Cephalometric analysis was used to determine the craniofacial morphology at about 5 years of age. RESULTS: Compared with the BCCSP group, the BCCPP group demonstrated longer maxillary length, more protruded maxilla, more favorable jaw relation, more severely retroclined maxillary incisors, and larger overjet. CONCLUSIONS: The subjects with BCCPP had craniofacial characteristics that differed significantly from those with BCCSP. It could also be speculated that palatal repair had more adverse effect on the growth of the maxilla in length; however, that repair influenced less the anteroposterior position of maxillary incisors than lip repair did.     

Atypical presentation of bilateral supplemental maxillary central incisors with unusual talon cusp

Delayed eruption of maxillary permanent central incisors in a child poses a distressing esthetic quandary to parents, by virtue of its location in the dental architecture. Well-aligned anterior teeth add confidence to smile and have enhanced self-esteem, which is critical even in early life. Impaction of the maxillary central incisors compared to third molars or the canines is less reported; bilateral supplemental maxillary central incisors related to impacted permanent maxillary central incisors are rare and one of the supplemental central incisors showing unusual talon is still infrequent. A case of impacted maxillary permanent central incisors related to supplemental maxillary central incisors, with one of them showing an unusual talon cusp, is presented.     

Sexual dimorphism of primary dentition in Spanish children

Aim: To analyse differences in the eruption of primary teeth between both sexes.

Materials and methods: A cross-sectional study was performed in a sample of 1250 children aged between 3 and 42 months. The clinical emergence of teeth was taken to estimate average ages for primary teeth eruption. The t-test was used to analyse gender and arch differences.

Results: Eruption of primary teeth began at the same time in girls as in boys; although the eruptive process was longer in girls. It was observed that almost all deciduous teeth emerged earlier in boys, except for the first molar (upper and lower) and the maxillary central incisors. The differences were statistically significant for almost all the primary teeth except for the central incisors, both upper and lower.

Conclusions: By comparing the timing of the eruption of primary teeth in both sexes, it was found that eruption of almost all primary teeth took place earlier in boys than in girls and that the eruption process was shorter for boys than for girls. Most of the deciduous teeth erupted earlier in the right side in both sexes. No differences were found in the sequence of eruption of primary teeth between genders.     

Eruption age of permanent mandibular first molars and central incisors in the south Indian population.

OBJECTIVE: The existing eruption schedules for permanent and deciduous dentition are based on studies in the Western population. Since Indians differ from Westerners racially, genetically, and environmentally, these studies fail to provide relevant guidance on the eruption schedule in the Indian population. This study aims at determining the eruption pattern of permanent mandibular molars and central incisors in the south Indian population. MATERIALS AND METHODS: 10,156 apparently healthy Indian children in the age-group of 6-9 years were examined with mouth mirror and probe under adequate illumination for the status of the eruption of the permanent mandibular first molar and permanent mandibular central incisor. Pearson's Chi-square test with Yates' continuity correction was used to calculate the P -value for comparison of proportion between girls and boys. The values obtained in our study were compared with the standard values. The Z-test with continuity correction was used to calculate the P -value. RESULTS: As per our study, the permanent mandibular first molars and central incisors erupted one to two years later compared to the values reported in Westerners. The earlier eruption of the permanent mandibular first molars compared to the permanent mandibular central incisors, as well as the earlier eruption of both the teeth in girls compared to boys, were in accordance with the existing literature. CONCLUSION: The eruption age reported by us may form a standard reference for eruption age in Indians.     

A review of impacted permanent maxillary cuspids--diagnosis and prevention

As impacted permanent maxillary cuspids occur in 1-2% of the population, the general dentist should know the signs and symptoms of this condition and the interceptive treatment. Features of buccal or palatal cuspid impaction include lack of canine bulges in the buccal sulcus indicating a lingual eruption path and possible impaction; lack of symmetry between the exfoliation and eruption of cuspids that may indicate palatal or lingual impaction; and abnormal mesiodistal location and angulation of the developing maxillary permanent cuspids on radiographs. Diagnosis of impacted cuspid teeth at age 8-10 years can significantly reduce serious ramifications, including surgical exposure and orthodontic alignment as well as root resorption of the lateral incisors. In specific cases, extraction of the primary maxillary cuspids can prevent impaction of the permanent maxillary cuspids and additional sequelae.     

Dental Anomalies as a Microsymptom of Palatal Canine Displacement

AIM: A retrospective study was performed to investigate whether palatal canine displacement is associated with other dental features permitting early clinical diagnosis of the eruption disturbance. PATIENTS AND METHODS: The study was based on the complete records of 235/8556 patients at the Department of Orthodontics, School of Dental Medicine, University of Freiburg i.Br. (mean age = 14.11 years) with at least one palatally displaced permanent canine. These patients were examined for ten different morphologic parameters, e.g. impaction and congenital absence of further teeth, hypoplastic, peg-shaped, rotated and congenitally missing upper lateral incisors, supernumerary teeth, Angle classification, and cover-bite (= "Deckbiss"). The data were compared with those of a control sample of the same size with physiologic upper canine eruption (mean-age = 10.0 years). Furthermore, in a right/left comparison the local influence of anomalies of the upper lateral incisors on palatal canine displacement was evaluated by multiple linear regression analysis. RESULTS: The statistical analyses revealed that the risk of palatal canine displacement was significantly higher in patients with hypoplasia, peg shape or congenital aplasia of upper lateral incisors, further impacted and congenitally missing teeth and cover-bite. The intergroup differences in terms of gender, rotation of upper lateral incisors and Angle classification were not statistically significant. The right/left comparison revealed a significantly higher risk of palatal canine displacement in association with an adjacent hypoplastic or peg-shaped lateral incisor and with aplasia of the contralateral upper incisor. CONCLUSION: The clinical significance of the study is that the occurrence of palatally displaced canines is often closely linked with other dental anomalies. In this context, anomalies of upper lateral incisors, aplasia or impaction of further teeth, and the anomaly of cover-bite may serve as indicators of palatal canine displacement. A retarded development of the upper lateral incisor seems to be more disturbing for physiologic canine eruption than aplasia. In patients exhibiting the stated microsymptoms, close clinical follow-up of the maxillary permanent canine eruption during the late exfoliation period is strongly recommended.     

An epidemiological survey of the time and sequence of eruption of permanent teeth in 4-15-year-olds in Tehran, Iran

AIM: The aims of this study were to define the average time of eruption of permanent teeth, the range of variation of the eruption time of each tooth, and their sequence of eruption amongst boys and girls in Tehran, Iran. METHODS: The population under study comprised 3744 pupils and students in the 4-15-year-old age group (1786 girls and 1958 boys) who were randomly selected from schools and training centres in the 20 districts covered by the General Department of Education and Training in Tehran. The research was carried out on a cross-sectional basis. The average age at eruption of permanent teeth, excluding third molars, was given as the mean (+/- SD) and median in months for each gender. A table of percentiles of the eruption time was also determined. RESULTS: The results show that, with the exception of the maxillary second premolars, the average age at eruption of permanent teeth in girls is less than in boys. The results also show that mandibular teeth have an earlier eruption time than maxillary teeth in both boys and girls. By the age of 96 months, 97% of the girls had all their first permanent molars. In boys, the corresponding age was 99 months. Amongst girls, maxillary canines erupt earlier than maxillary second premolars. CONCLUSION: On average, girls have their permanent teeth erupt earlier than boys. The sequence of eruption differs between girls and boys for maxillary canines and maxillary second premolars.     

Maxillary sinus volume in patients with impacted canines

Objectives:To evaluate the maxillary sinus volumes in unilaterally impacted canine patients and to compare the volumetric changes that occur after the eruption of canines to the dental arch using cone beam computed tomography (CBCT).Materials and Methods:Pre- (T0) and posttreatment (T1) CBCT records of 30 patients were used to calculate maxillary sinus volumes between the impacted and erupted canine sides. The InVivoDental 5.0 program was used to measure the volume of the maxillary sinuses. The distance from impacted canine cusp tip to the target point on the palatal plane was also measured.Results:Right maxillary sinus volume was statistically significantly smaller compared to that of the left maxillary sinus when the canine was impacted on the right side at T0. According to the T1 measurements there was no significant difference between the mean volumes of the impaction side and the contralateral side. The distance from the canine tip to its target point on the palatal plane were 17.17 mm, and the distance from the tip to the target point was 15.14 mm for the left- and right-side impacted canines, respectively, and there was a significant difference between the mean amount of change of both sides of maxillary sinuses after treatment of impacted canines.Conclusions:Orthodontic treatment of impacted canines created a significant increase in maxillary sinus volume when the impacted canines were closer with respect to the maxillary sinus.     

Management of inverted impacted primary incisors: an unusual case

The prevalence of impacted primary teeth has been reported to be very rare and it has been reported to occur in 1:10,000 times, most commonly involving the primary second molars. This report discusses the presence of an impacted inverted maxillary primary incisors and their management by surgical intervention in a 5 year old boy. The inverted primary maxillary central incisors were extracted and prosthetic rehabilitation was done to improve the esthetics, speech and psychosocial behavaviour of the child. Co-incidentally the permanent maxillary incisors were also found to be hypoplastic although the parents did not give any history of trauma to the maxillofacial complex. It is important for pediatric dental surgeons to carefully monitor the eruption of primary and permanent teeth for early identification and management of developmental anomalies.     

上颌中切牙与尖牙同时阻生的临床特征分析

目的分析上颌中切牙与同侧尖牙同时阻生病例的临床特征。方法选择上颌中切牙与同侧尖牙同时阻生病例21例,分析上颌中切牙阻生类型与尖牙阻生情况,测量阻生侧及对侧侧切牙发育或萌出异常情况。结果与中切牙阻生同时发生的尖牙76.2%为唇侧阻生,其中完全易位与不完全易位占唇侧阻生尖牙的68.8%,尖牙唇侧阻生病例中侧切牙根远中倾斜和伴牙冠近中倾斜者占87.5%,尖牙唇侧或腭侧阻生病例中,出现锥形或过小等畸形侧切牙的比例分别为31.25%和40.00%。上颌中切牙与尖牙不同阻生类型患者,前牙反牙合比例都超过40%,且多为牙型反牙合。结论与中切牙阻生同时发生的尖牙阻生多为唇侧阻生,与中切牙阻生类型无关,与侧切牙根远中倾斜高度相关,尖牙完全易位与过小或锥形等畸形侧切牙有关。     

Morphological relationship analysis of impacted maxillary canines and the adjacent teeth on 3-dimensional reconstructed CT images

Objective:To examine whether there is a relationship between maxillary canine impaction and the morphologic characteristics of the maxillary dentition, especially the root of the lateral incisor.Materials and Methods:In this study, we selected only patients with unilateral maxillary canine impaction to compare the morphologic characteristics of the dentition on the impaction side and the clinically normal eruption side. The sample size was decided to be 40 based on the pilot study. To minimize bias depending on sex and location of the maxillary canine impaction, we selected equal numbers (20) of boys and girls, and equal cases (20) of buccal impaction and palatal impaction. Under the aforementioned conditions, the mean age was 13.5 ± 2.3 years. The multislice spiral computed tomography images of these 40 subjects were converted into three-dimensional (3D) reconstructed images using the OnDemand 3D program (Cybermed Co, Seoul, Korea). Then we measured the morphologic characteristics of the individual teeth on the obtained 3D teeth images.Results:Length and volume of the maxillary lateral incisor''s roots were significantly smaller on the impaction side compared with the normal eruption side (P = 0.001 and P = 0.006, respectively). The width and volume of the canine''s crown were significantly greater on the impaction side compared with the normal eruption side (P = 0.020 and P < .0001, respectively).Conclusion:These results might help to prove the hypothesis that the smaller-sized lateral incisor roots and greater-sized canine crowns are the influential etiologic factors in maxillary canine impaction.     

Prevalence and distribution of anomalies of permanent dentition in 9584 Japanese high school students

This study investigated the prevalence and distribution of anomalies of permanent dentition in the current Japanese population by examining an unbiased sample. We conducted a survey of dental anomalies by mass dental screening at eight high schools in 2012. Participants were all students with permanent dentition. Dental anomalies were classified as hypodontia, supernumerary teeth, peg-shaped teeth, fused teeth, and talon cusps. Students with one or more dental anomalies on oral examination were given a differential diagnosis by three specialists. The final sample comprised 9584 participants (5062 boys, 4522 girls). Hypodontia was present in 372 students (3.88 %) with no significant sex difference (191 boys, 181 girls). Frequent sites were the right or left mandibular second premolar, right or left maxillary second premolar, and right or left maxillary lateral incisor. Supernumerary teeth were observed in three boys (0.06 %) and one girl (0.02 %). Peg-shaped teeth were observed in 74 students (0.77 %; 27 boys, 47 girls), differing significantly between sexes; they were most prevalent among maxillary lateral incisors. Of affected students, 18 students (0.19 %) also had hypodontia (3 boys, 15 girls). Fused teeth were present in two boys (0.04 %) and three girls (0.07 %) (gemination in one boy and fusion in the remaining four students). Sites were limited to maxillary and mandibular central and lateral incisors. Talon cusps were observed in two boys (0.04 %) and four girls (0.09 %). The present survey of a large unbiased sample can be considered to reflect the prevalence and distribution of anomalies of permanent dentition in the current Japanese population.     

Anomalies of deciduous teeth and findings in permanent dentition]

Prevalence of anomalies of deciduous teeth has been analyzed in the general population of Zagreb preschool children. The sample comprised 2,987 children from 3 to 6 years of age (1,582 boys and 1,405 girls). Hypodontia was found in 0.47%, hyperdontia in 0.10%, and double teeth in 0.43% of total sample. Total prevalence of all anomalies in the sample was 1.0%. The sample for the analysis of permanent dentition has been enlarged with the clinical sample of children having the same anomalies and comprised 48 children. In all children with anomalies of primary teeth the orthopantomograms were taken and the status of permanent dentition was analyzed. In children with hypodontia in primary dentition hypodontia of permanent teeth was found in 100% of cases. Patients with hyperdontia of primary teeth displayed anomalies in permanent dentition in 85.7%, while in children with primary double teeth, anomalies of permanent teeth were present in 61.1% of cases. Missing deciduous teeth were found in both jaws in only 8.7% of cases, and in 34.8% in permanent dentition. Symmetrical occurrence of hypodontia of primary teeth (i.e. in both sides of jaws) was significantly higher in boys (56.3%) than in girls (28.6%). In permanent dentition symmetrical occurrence of hypodontia was significantly higher than in primary dentition (81.3% in boys and 57.1% in girls). The most frequently missing primary teeth were maxillary lateral incisors (48.8%) followed by mandibular central incisors (34.9%). Hyperdontia of primary teeth has been found only in boys, and it related only to the maxillary lateral incisors. Anomalies of deciduous teeth show a high degree of association with the finding in the permanent dentition.(ABSTRACT TRUNCATED AT 250 WORDS)     

Orthodontic approach to dilacerated central incisor localized horizontally on the anterior nasal spine: a case report

The purpose of this paper was to present a case of surgical exposure of a horizontally impacted permanent maxillary left central incisor followed by fixed orthodontic treatment to eruption in a 9-year-old boy with a 2-mm overjet and 2-mm overbite who had sustained a traumatic injury to his primary maxillary central incisors when he was 6-years-old. Panoramic, occlusal, and cepholometric radiographs showed the affected tooth's crown to be positioned horizontally, and a CT scan showed the impacted central incisor's crown to be located below the anterior nasal spine and its apex to be located parallel to the palatal plane. A treatment plan was devised that included surgically exposing the impacted teeth and applying extrusive forces in the direction of the occlusal plane to bring about eruption. After 22 months of treatment, the central incisor erupted into the oral cavity. The patient now possesses the confidence to smile and enhanced self-esteem.     

Three-dimensional inclination of the dental axes in healthy permanent dentitions--A cross-sectional study in a normal population

The 3-dimensional (3-D) inclination of the facial axis of the clinical crown (FACC) and the size of the clinical crowns were measured in 100 white northern Italians. The subjects consisted of 22 girls and 21 boys, ages 13-15 years (adolescents), and 31 women and 26 men, ages 16-26 years (adults), all with a complete permanent dentition and Class I dental relationships. The 3-D coordinates of dental landmarks were obtained with a computerized electromagnetic digitizer. Clinical crowns heights and FACC inclinations in the anatomical frontal and sagittal planes relative to 2 reference planes, maxillary and mandibular (between the incisive papilla and the intersection of the palatal/lingual sulci of the first permanent molars with the gingival margin), were calculated. Ages and sexes were compared by ANOVA. On average, the frontal plane FACCs of most teeth converged toward the midline plane of symmetry. In contrast, the incisors diverged from the midline plane or were nearly vertical. Within each quadrant, the inclinations of the postincisor teeth progressively increased. In the sagittal plane, most teeth had a nearly vertical FACC. FACC inclinations showed sex- and age-related differences (P < .05). In the frontal plane, the canines, premolars, and molars were more inclined in adolescents than in adults. In the sagittal plane, a large within-group variability was observed. Clinical crown height was significantly larger in males than in females in all maxillary and mandibular canines, premolars, second molars, maxillary central incisors, and first molars. With age, some degree of dental eruption was found in maxillary and mandibular canines, maxillary second premolars, and molars. The age-related decrease in FACC inclination may be the effect of a progressive buccal and mesial drift.     

Bilateral maxillary fused primary incisors accompanied by succedaneous supernumerary teeth: report of a case

Summary. A rare case of fusion between maxillary primary central incisors and supplemental teeth occurring bilaterally, accompanied by succedaneous supernumerary teeth, is presented. The patient was an 8·5-year-old Japanese boy. Intraoral examination revealed fusion of left and right maxillary primary central incisors to supplemental teeth, which had labial and lingual grooves. The maxillary primary lateral incisors were present. Radiographs showed that the fused teeth had separate roots, pulp chambers and root canals. There were two impacted supernumerary teeth and eruption of the permanent maxillary central incisors was delayed. Treatment was performed and the fused primary teeth and the impacted supernumerary teeth were extracted. After 6 months observation, surgical exposure of the two crowns of the permanent maxillary central incisors was performed. The teeth began to erupt and have since been kept under observation.     

Multiple supernumerary teeth associated with an impacted maxillary central incisor: Surgical and orthodontic management

Various anomalies in the size, shape, number, structure and eruption of the teeth are often observed clinical conditions. Supernumerary teeth can be found in almost any region of the dental arch, and most of the times they are asymptomatic, and are routinely found during radiographic evaluation. The most common cause of impacted maxillary incisors is the presence of the supernumerary teeth. This paper describes a case of multiple supernumerary teeth associated with an impacted permanent maxillary central incisor in an 11-year old child along with its surgical and orthodontic management.     

Prevalence of malocclusion and orthodontic treatment need in children and adolescents in Bogota, Colombia. An epidemiological study related to different stages of dental development

The aim of the study was to assess the prevalence of malocclusion in a population of Bogotanian children and adolescents in terms of different degrees of severity in relation to sex and specific stages of dental development, in order to evaluate the need for orthodontic treatment in this part of Colombia. A sample of 4724 children (5-17 years of age) was randomly selected from a population that attended the Dental Health Service; none had been orthodontically treated. Based on their dental stages the subjects were grouped into deciduous, early mixed, late mixed and permanent dentition. The registrations were performed according to a method by Bj?rk et al. (1964). The need for orthodontic treatment was evaluated according to an index used by the Swedish National Board of Health. The results showed that 88 per cent of the subjects had some type of anomaly, from mild to severe, half of them recorded as occlusal anomalies, one-third as space discrepancies, and one-fifth as dental anomalies. No clear sex differences were noted, except for maxillary overjet, spacing, tooth size (all more frequent in boys), and crowding (more frequent in girls). Occlusal anomalies and space discrepancies varied in the different dental developmental periods, as did tipped and rotated teeth. Little need for orthodontic treatment was found in 35 per cent and moderate need in 30 per cent. A great need was estimated in 20 per cent, comprising children with prenormal occlusion, maxillary overjet, or overbite (> 6 mm), posterior unilateral crossbite with midline deviation (> 2 mm), severe crowding or spacing, congenitally missing maxillary incisors, impacted maxillary canines or anterior open bite (> 3 mm in the permanent dentition). Urgent need for treatment was estimated to be 3 per cent, comprising subjects with extreme post- and pre-normal occlusion, impacted maxillary incisors or extensive aplasia.     

The treatment timing of labial inversely impacted maxillary central incisors: A prospective study

Objective:To determine the timing of treatment for the labial inversely impacted maxillary central incisors.Methods:Twenty-eight patients (mean age, 8.2 years) with labial inversely impacted maxillary central incisors were divided into early-treated and later-treated groups according to their dental age. All of the patients were treated with a combination of surgery and orthodontic traction using the Guide rod appliance. Cone-beam computed tomography images were taken immediately after treatment for assessing the root morphology, root length, and alveolar bone loss. Sagittal slices were evaluated at the widest labial-lingual width of the tooth in the axial view. All variables were evaluated by Simplant 13.0 software (Materialise Dental NV, Leuven, Belgium).Results:The rank sum test indicated that the root length of two groups showed a statistically significant difference between the impacted and homonym tooth, with a shorter length in the impacted tooth (P < .05). The D-value (difference of root length between the impacted and homonym tooth) and alveolar bone loss on the labial side of the impacted incisor are significantly less in the early-treated groups when compared with the later-treated groups (P < .05). Spearman rank correlation analysis showed a statistically positive association between the treatment timing and D-value (r  =  .623, P < .05). The chi-square test for morphology of root apex indicated that the incidence of the root-apex-directed labial side is significantly higher in the later-treated groups when compared with the early-treated groups.Conclusion:The labial inversely impacted maxillary central incisors should be treated early to promote root development by achieving a better morphology of root apex, thus reducing the risk of alveolar bone loss on the labial side.