Variations in number and morphology of permanent teeth in 7-year-old Swedish children

Expert consensus on imaging diagnosis and analysis of early correction of childhood malocclusion

Early correction of childhood malocclusion is timely managing morphological, structural, and functional abnormalities at different dentomaxillofacial developmental stages. The selection of appropriate imaging examination and comprehensive radiological diagnosis and analysis play an important role in early correction of childhood malocclusion. This expert consensus is a collaborative effort by multidisciplinary experts in dentistry across the nation based on the current clinical evidence, aiming to provide general guidance on appropriate imaging examination selection, comprehensive and accurate imaging assessment for early orthodontic treatment patients.

Prevalence of Dental Anomalies in Pediatric Patients at King Saud University Dental Hospital, Riyadh, Saudi Arabia-A Radiographic Analysis

OBJECTIVES

To record the prevalence of dental anomalies in children visiting King Saud Dental Hospital, Riyadh, Saudi Arabia.

MATERIALS AND METHODS

This cross-sectional study involved radiographic examination of children aged 6 to 14 years who visited King Saud Dental Hospital, Riyadh, Saudi Arabia, in the past five years. Four dental interns were trained in three consecutive sessions by a pediatric dentist and evaluated the orthopantomograms of the children. The recorded anomalies were divided into four categories: tooth number, size, position, and general. Descriptive statistics were derived and chi-square tests performed to report prevalence and significance among genders, medical histories, and dental anomalies. The significance level was set at p < 0.05.

RESULTS

Of the 1987 radiographs studied, 268 (13.48%) children had dental anomalies. The sample consisted of 51.1% female and 48.5% male children, with a mean age of 11.87 ± 2.1 years. Most study participants had mixed dentition and were healthy. The prevalence of dental anomalies reported in this study was as follows: 4.6% hypodontia, 2.7% ectopic eruption, 1.63% taurodontism, 1.2% infra-occluded molars, 1.1% impacted teeth, 0.75% root dilaceration, and 0.65% supernumerary teeth. Significant correlations were found between gender and ectopic eruption (p = 0.02) and between medical history and hypodontia (p = 0.00), ectopic eruption (p = 0.048), and root dilaceration (p = 0.03).

CONCLUSIONS

This study showed that hypodontia was the most common dental anomaly, followed by ectopic eruption and taurodontism. The findings of this study may guide dentists in better understanding, diagnosing, and treating dental anomalies in children in Riyadh, Saudi Arabia.

Congenitally missing permanent canines in a sample of Chinese population: a retrospective study

BACKGROUND

Congenitally missing permanent canines (CMPC) have a significant impact on function and aesthetics. The prevalence is low, and the availability of rigorous studies on this issue in China is limited. This study was designed to investigate the prevalence and distribution of CMPC in patients and concomitant anomalies. Additionally, we aimed to compare the prevalence of CMPC between two age groups.

METHODS

A total of 10,447 patient's panoramic radiograph (PR) images from August 2021 to December 2023 were reviewed and data regarding the location and number of CMPCs were recorded. Age and gender were obtained from the clinical records. Additionally, concomitant anomalies such as persistent primary canines, congenitally missing other permanent teeth, supernumerary teeth and microdontia were also recorded in patients with CMPC. 10,447 patients were divided into two groups: group A (< 121 months of age) and group B (≥ 121 months of age) to record the number of patients with CMPC. The data were presented as counts (n) and percentages (%), and statistically analysed using the Chi-square test.

RESULTS

The average age of patients with CMPC was 9.2 years, with a prevalence of 0.69% (n = 72). The difference between genders was not statistically significant (p = 0.950). The prevalence of CMPC in group B (1.08%, 26/2400) was significantly greater than that in group A (0.57%, 46/8047) (p = 0.008). 89.42% (93/104) of the missing permanent canines had visible primary canines in patients. CMPC were more likely to occur in the maxilla (91.67%) than in the mandible (6.94%) (p<0.001). No significant difference was found between the left and right sides (p = 0.844). With respect to concomitant anomalies among those with CMPC, 22 patients had 58 congenitally other permanent teeth missing, 3 patients had 3 supernumerary teeth, and 12 maxillary lateral incisors from 7 patients presented with microdontia.

CONCLUSIONS

The prevalence of CMPC was 0.69%. CMPC were more likely to occur in the maxilla in the presence of persistent primary canines and were not influenced by gender or side. Early panoramic radiographs can improve the detection rate of CMPC, thereby facilitating prompt intervention and timely management.

Prevalence, Occurrence, and Characteristics of Supernumerary Teeth Among the Saudi Arabian Population Using Panoramic Radiographs

BACKGROUND

Supernumerary teeth numerical anomalies and the early diagnosis of supernumerary teeth is very important to avoid potential complications. The study aim was to determine the prevalence, occurrence, and characteristics of supernumerary teeth among the Arabian population.

METHODS

A retrospective radiographic study was performed using panoramic radiographs of patients attending a teaching hospital from January 2018 to December 2020. Only healthy patients with clear radiographs were included in the study, and patients with syndromes, cleft lip, and palate, and unclear radiographs were excluded from the study. The details include the patient's age and gender, supernumerary tooth number, location, orientation, and position. Only a single examiner was involved in the data collection and analysis.

RESULTS

Overall, 38 (2%) patients were observed with 47 supernumerary teeth. Among them, 76% were males and 24% were females, with a mean age of 16.1 ± 9.7 years. Mesiodens (87%) are the common type of supernumerary tooth, and the majority of the supernumerary teeth were impacted (66%). The majority of the patients presented with a single supernumerary tooth, while 24% of the patients presented with two supernumerary teeth. Sixty percent of the supernumerary teeth were conical in morphology, followed by a tuberculate morphology. In the study population, most of the supernumerary teeth were normal in orientation.

CONCLUSIONS

The prevalence of supernumerary teeth was 2%. Among them, the majority were observed at the anterior region of the maxillary arch with a conical shape of normal orientation. The gender-based comparison of location, orientation, morphology, eruption, and number of supernumerary teeth showed male predilection.

Congenitally Missing Lateral Incisors: Prioritizing Space Closure Whenever Feasible

Congenital missing teeth are among the most prevalent dental malformations. Maxillary lateral incisors are particularly prone to agenesis, often missing bilaterally. This condition presented complex challenges for both patients and clinicians. The etiology of maxillary lateral incisor agenesis is multifactorial, involving genetic and environmental factors. The management is also inherently complex, necessitating an interdisciplinary approach. Treatment options include orthodontic space closure, resin-bonded bridges, implants, removable partial dentures, and autotransplantation. Among these, implant placement and orthodontic space closure are most commonly preferred by clinicians. The selection of an appropriate treatment modality depends on multiple factors, such as patient growth, available space, condition of adjacent teeth, and initial malocclusion. This review aimed to evaluate and compare various treatment options for maxillary lateral incisor agenesis, providing a comprehensive analysis of the latest evidence and highlighting the benefits and limitations of each approach to inform clinical decision-making.

Restoration of a Peg Lateral Incisor Using the Putty Index Technique: A Case Report

The restoration of peg lateral incisors poses considerable aesthetic and functional issues. This case report describes the use of a putty index approach for conservatively restoring peg-shaped maxillary lateral incisors with resin composites. A 21-year-old female patient with good periodontal health and appropriate occlusal interactions had treatment at the Department of Conservative Dentistry and Endodontics. The restoration method included initial impressions, shade selection, etching, bonding, and gradual composite application, followed by curing and polishing. The putty index was used as a reference to accurately recreate the palatal enamel. This approach provides a low-cost, minimally intrusive treatment that maintains natural tooth structure while producing satisfactory aesthetic outcomes. Direct adhesive resin restorations are being highlighted as a feasible option, as technology and bonding techniques progress. This case shows the significance of modifying treatment plans based on patient characteristics and practitioner expertise.

Generalized Non-syndromic Hypertaurodontism With Delayed Eruption: A Case Report

Taurodontism is a rare dental anomaly defined by a change in tooth shape due to Hertwig's epithelial sheath not folding inward at the right horizontal level. It has a larger pulp chamber and a pulpal floor that is shifted apically, and the cementoenamel junction (CEJ) is not constricted. This condition is more frequently observed in permanent teeth than in primary teeth and can occur in a bilateral or unilateral manner, affecting any quadrant or group of teeth. This brief case report discusses a 14-year-old female patient who presented with complaints of decayed teeth in the lower right and left posterior regions of the jaw. Radiographic examination revealed the presence of non-syndromic taurodontism in both the deciduous teeth and their permanent successors. Dental management included oral prophylaxis, application of pit and fissure sealants, indirect pulp capping, and restoration with glass ionomer cement for the affected teeth.

CT and MR Appearance of Teeth: Analysis of Anatomy and Embryology and Implications for Disease

Abnormalities of dental development and anatomy may suggest the presence of congenital or acquired anomalies. The detection of abnormalities, therefore, is an important skill for radiologists to achieve. Knowledge of dental embryology and an understanding of the radiologic appearances of teeth at various stages of maturation are required for the appreciation of abnormal dental development. While many tooth abnormalities are well-depicted on dedicated dental radiographs, the first encounter with a dental anomaly may be by a radiologist on a computed tomographic (CT) or magnetic resonance (MR) exam performed for other reasons. This article depicts normal dental anatomy and development, describing the appearance of the neonatal dentition on CT and MRI, the modalities most often encountered by clinical radiologists. The radiology and dental literature are reviewed, and key concepts are illustrated with supplemental cases from our institution. The value of knowledge of dental development is investigated using the analysis of consecutive MR brain examinations. Finally, the anatomical principles are applied to the diagnosis of odontogenic infection on CT. Through analysis of the literature and case data, the contrast of dental pathology with normal anatomy and development facilitates the detection and characterization of both congenital and acquired dental disease.

Co-Occurrence of Taurodontism in Nonsyndromic Cleft Lip and Palate Patients in Subset of Indian Population: A Case-Control Study Using CBCT

The present study aimed to assess the co-occurrence of taurodontism in nonsyndromic cleft lip and palate (NSCLP) patients in a subset of Indian population using cone beam computed tomography (CBCT).

The study was a retrospective case-control kinds assessing 1500 CBCT scans over a period of 2 years; 67 scans out of 1500 showed cleft lip and palate (CLP). After fulfilling the inclusion and exclusion criteria, 38 subjects out of 67 comprised the case group; 80 randomly selected subjects constituted the control group. The first and second permanent molars in both the arches (8 teeth) of each subject were assessed for the presence and severity of taurodontism using the objective criteria. Statistical analysis was done using the χ2 test. Inter and intraobserver agreement was evaluated by Kappa statistics.

71.05% subjects showed taurodontism in case group, while 45% subjects showed its presence in control group; results being significant for both the groups. However, the comparison of number of teeth with taurodontism in the 2 groups came out to be statistically insignificant. Also no significant association of taurodontism was seen with gender or the different types of cleft (P = .437). Hypotaurodontism was the most prevalent type.

There was a higher prevalence of taurodontism in both groups which had been underestimated in the previous studies. This emphasizes the significance of the use of CBCT in detection of dental anomalies which would otherwise go undetected.

Interventions to facilitate the successful eruption of impacted maxillary incisor teeth due to the presence of a supernumerary: A systematic review and meta-analysis

INTRODUCTION

A failure of maxillary incisor eruption is commonly attributed to the presence of a supernumerary tooth. This systematic review aimed to assess the percentage of impacted maxillary incisors that successfully erupt after surgical removal of supernumerary teeth with or without other interventions.

METHODS

Systematic literature searches without restrictions were undertaken in 8 databases for studies reporting any intervention aimed at facilitating incisor eruption, including surgical removal of the supernumerary alone or in conjunction with additional interventions published up to September 2022. After duplicate study selection, data extraction, and risk of bias assessment according to the risk of bias in nonrandomized studies of interventions and Newcastle-Ottawa scale, random-effects meta-analyses of aggregate data were conducted.

RESULTS

Fifteen studies (14 retrospective and 1 prospective) were included with 1058 participants (68.9% male; mean age, 9.1 years). The pooled eruption prevalence for removal of the supernumerary tooth with space creation or removal of the supernumerary tooth with orthodontic traction was significantly higher at 82.4% (95% confidence interval [CI], 65.5-93.2) and 96.9% (95% CI, 83.8-99.9) respectively, compared with removal of an associated supernumerary only (57.6%; 95% CI, 47.8-67.0). The odds of successful eruption of an impacted maxillary incisor after removal of a supernumerary were more favorable if the obstruction was removed in the deciduous dentition (odds ratio [OR], 0.42; 95% CI, 0.20-0.90; P = 0.02); if the supernumeraries were conical (OR, 2.91; 95% CI, 1.98-4.28; P <0.001); if the incisor was in the correct position (OR, 2.19; 95% CI, 1.14-4.20; P = 0.02), at the level of the gingival third (OR 0.07; 95% CI, <0.01-0.97; P = 0.04) and had incomplete root formation (OR, 9.02; 95% CI, 2.04-39.78; P = 0.004). Delaying removal of the supernumerary tooth 12 months after the expected eruption time of the maxillary incisor (OR, 0.33; 95% CI, 0.10-1.03; P = 0.05) and waiting >6 months for spontaneous eruption after removal of the obstacle (OR, 0.13; 95% CI, 0.03-0.50; P = 0.003) was associated with worse odds for eruption.

CONCLUSIONS

Limited evidence indicated that the adjunctive use of orthodontic measures and removal of supernumerary teeth might be associated with greater odds of successfull impacted incisor eruption than removal of the supernumerary tooth alone. Certain characteristics related to supernumerary type and the position or developmental stage of the incisor may also influence successful eruption after removal of the supernumerary. However, these findings should be viewed with caution as our certainty is very low to low because of bias and heterogeneity. Further well-conducted and reported studies are required. The results of this systematic review have been used to inform and justify the iMAC Trial.

Evaluation of the dimensional alternation of the alveolar bone in patients with a congenitally missing mandibular lateral incisor using cone-beam computed tomography

INTRODUCTION

The alveolar bone is an essential consideration when planning treatment for patients with tooth agenesis. This study evaluated the changes in the alveolar bone and adjacent teeth in patients with a congenitally missing mandibular lateral incisor using cone-beam computed tomography.

METHODS

Twenty-three nonorthodontically treated adults with a unilateral congenitally missing mandibular lateral incisor were the missing group (M group). The control group (C group) consisted of 23 nonorthodontically treated adults with normal occlusion and no missing teeth. First, the difference in the arch perimeter between the groups was compared at the cementoenamel junction (CEJ) level and the root apex (RA) level. Next, the root divergence of the anterior teeth in the M group was observed. Finally, the alveolar bone thickness ratio was compared between the M and C groups at different vertical levels.

RESULTS

The arch perimeter was significantly decreased in the M group at the CEJ and RA levels (P <0.05). Root divergence was observed adjacent to the missing site (P <0.0001). There were a reduction in total and cancellous cortical alveolar bone thickness (ABT) ratios at the 3-, 6-, and 9-mm positions (P <0.05). The buccal cortical ABT ratios decreased at the 3-and 6-mm positions. The lingual ABT ratio increased at the 9-mm position (P <0.05).

CONCLUSIONS

The congenitally missing mandibular lateral incisor caused a reduction in the arch perimeter in the CEJ area and the RA area. The root divergences were observed in the teeth adjacent to the missing areas. A significant decrease in the buccal cortical bone and cancellous bone was observed in the missing area.

Morphological Diversity of Permanent Maxillary Lateral Incisors and Their Impact on Aesthetics and Function in Orthodontically Treated Patients

The aim of this study was to determine the frequency of different crown shapes and associated dental anomalies of the permanent maxillary lateral incisor (PMLI) and their impact on aesthetics and occlusion (function) in orthodontically treated patients. Materials and Methods: The records of 372 subjects, which consisting of study casts, panoramic radiographs and anamnestic data, were investigated for crown shape and associated dental anomalies of PMLI and potential dental treatment to achieve satisfactory aesthetics and function. Descriptive statistics, including means, standard deviations and percentages for the observed variables, were calculated. Data were analyzed using the chi-square test. p-Values < 0.05 were considered as statistically significant. Results: The results showed that the most common crown shapes of PMLI were trapezoidal-shaped (59.8%), followed by central incisor-shaped (26.7%), canine-shaped (11.2%) and peg-shaped (2.3%), without statistically significant difference between genders. Developmental anomalies were found in 86 (11.6%) PMLI. All subjects with developmental anomalies were included in orthodontic treatment, and 91.2% of them need interdisciplinary treatment to achieve satisfactory aesthetics and function. Conclusions: The morphological diversity and developmental anomalies of the PMLI may affect aesthetics and function and should be considered in treatment planning.

Clinical and Radiographical Evaluation of Non-syndromic Dental Anomalies in Turkish Children

AIM: The aim of this study was to investigate the frequency and distribution of non-syndromic developmental dental anomalies in Turkish children in different age groups. SUBJECTS AND METHODS: A sample of 516 children aged 3–17 years who attended the Pediatric Dentistry Department of Istanbul Aydin University were evaluated clinically and radiographically for the existence of any structural, shape, and number anomalies of the developing dentition, and the most prevalent anomalies were compared according to gender and age groups. RESULTS: The most observed dental anomaly was Molar Incisor Hypomineralization (MIH) and tooth agenesis by a percentage of 14.3% and 4.8%, respectively. The incidence of MIH was higher in 7–8 and 9–10 years of age groups. There were no anomalies detected in 361 (70%) of the patients; meanwhile, only one anomaly was observed in 110 (21.3%), two different anomalies at the same time were observed in 33 (6.4%), and more than two anomalies were observed in 12 (2.3%) in the study group. STATISTICS: The statistical analysis of the results was obtained using the IBM SPSS Statistics 22 (IBM SPSS, Inc USA) program. p < 0.05 was considered to be statistically significant. CONCLUSION: Although there are no known systemic disturbances, at least, one dental anomaly was observed in 21.3% of the children. The most observed anomalies were MIH and tooth agenesis. An increase in the MIH prevalence throughout the world may lead to the suggestion that more investigations should be made on environmental predisposing factors. Besides, there might be common genetic factors and genes (PAX9, AXIN2, MSX1) affecting both tooth development and tumor formation which may be a potential risk marker for future cancer development.

Prevalence and Pattern of Non-syndromic Hypodontia among Adolescents in Southern Part of India

Background

Non-syndromic hypodontia is the most common developmental dental anomaly, but there is a paucity of literature on its prevalence and severity in the Indian population.

Aim and objectives

To estimate the prevalence of non-syndromic hypodontia among adolescent schoolchildren in the southern part of India.

Settings and design

This cross-sectional study was conducted in 20 schools from two states of southern India, named—Andhra Pradesh and Telangana. A total of 5,458 children in the age-group 13 to 15 years were selected.

Materials and methods

Clinical examination was carried out to check the absence of a permanent tooth and was confirmed by radiographic findings. The inclusion criterion was children with all the permanent teeth erupted (except third molars) and exclusion criteria were teeth missing due to reasons other than congenital agenesis. A Chi-square test was applied to check the significance.

Results

The total prevalence of hypodontia in the study sample was 1.4%. Girls displayed a higher prevalence value (1.9%) than boys (1.1%). Maxillary lateral incisor was the most commonly congenitally missing tooth, followed by mandibular incisors and mandibular second premolar. Overall, hypodontia with a predominance of unilateral pattern and a predilection for the left side was observed.

Conclusion

The most common missing permanent tooth (except third molars) was the maxillary lateral incisor. Hypodontia was more prevalent in females and had a predominance of unilateral patterns with a predilection toward the left side.

How to cite this article

Manasa Devi TL, Dutta B, Dwijendra KS, et al. Prevalence and Pattern of Non-syndromic Hypodontia among Adolescents in Southern Part of India. Int J Clin Pediatr Dent 2021;14(4):492–496.

Prevalence and Distribution of Nonsyndromic Dental Anomalies in Children in Eastern Saudi Arabia: A Radiographic Study

OBJECTIVES

To report the prevalence and distribution of nonsyndromic dental anomalies in children in eastern Saudi Arabia.

METHODS

This retrospective records review study involved radiographic examination of 6-18 years old pediatric patients who attended the Dental Hospital of the College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia. Four calibrated examiners recorded nonsyndromic dental anomalies from patients' digital orthopantomograms (OPG). The anomalies recorded were related to tooth number, shape, and location. Descriptive statistics, chi-square test, and Fisher exact tests were used to report prevalence and differences by gender, nationality, and medical history at the 5% significance level.

RESULTS

Of 2226 reviewed patients' records, 1897 met the inclusion criteria and were included in the study. The study sample had equal distribution of males (52.6%) and females (47.4%) and comprised 81.2% Saudi children with a mean age of 8.8 ± 1.84 years. Most study subjects (97.8%) were in mixed dentition and 88.7% were healthy. The prevalence of dental anomalies was as follows: teeth rotations (24.5%), ectopically erupted teeth (6%), congenitally missing permanent teeth (5.4%), peg lateral (1.1%), supernumerary (0.5%), gemination (0.3%), and fusion (0.1%). No statistically significant differences were found in the distribution of dental anomalies by patients' gender, medical history, and nationality (p value ≥0.05).

CONCLUSION

This study showed that teeth rotations were the most common dental anomalies followed by ectopic eruptions and congenitally missing teeth. The study findings may guide dental practitioners to better diagnose and manage children with dental anomalies in eastern Saudi Arabia.

Assessment of dens invaginatus and its characteristics in maxillary anterior teeth using cone-beam computed tomography

This cone-beam computed tomographic (CBCT) study aimed to evaluate the prevalence of dens invaginatus (DI) and its characteristics in maxillary anterior teeth in a Saudi population. A total of 505 CBCT scans were evaluated, including a total of 2790 maxillary anterior teeth. The patients' demographic data, including age and sex, were recorded. The presence of DI and the related characteristics including bilateral occurrence; DI type according to Oehlers classification; and presence of periapical radiolucency, open apex, and/or nearby impacted teeth were analyzed. The associations between DI and the other factors were analyzed using the chi-square and fisher exact tests. DI was detected in 7.3% of the patients and 1.6% of the teeth examined. Most of the DI-affected teeth were maxillary lateral incisors (76.1%), followed by mesiodens (19.6%) and maxillary central incisors (4.3%), while no DI was observed in the maxillary canines. Bilateral DI was found in 24.3% of the affected patients. Oehlers type I DI was the most frequent (80%). Periapical radiolucencies, open apices, and nearby impacted teeth were observed in 10.9%, 4.3%, and 30% of the invaginated teeth, respectively. DI was significantly associated with tooth type (P < 0.0001) but not with sex (P > 0.05). Although most of the DI cases are limited to the crown, CBCT imaging is essential for DI evaluation and management.

Late adverse effects of childhood acute lymphoblastic leukemia treatment on developing dentition

BACKGROUND

Childhood cancer survivors show a variety of late adverse effects on dental health. The purpose of this study was to examine the prevalence and severity of dental abnormalities in permanent dentition in childhood leukemia survivors.

MATERIALS AND METHODS

Retrospective analysis of panoramic radiographs was performed for 178 childhood leukemia survivors aged below 17 years at the time of diagnosis. Sex, age at diagnosis, interval between ALL diagnosis and the follow-up radiograph, treatment protocol, and risk grouping were recorded. Abnormalities of tooth development and defect index were used to assess the frequency and severity of dental abnormalities.

RESULTS

One hundred eight (61%) patients had no dental abnormalities at follow-up examination at a median of 6.1 years after diagnosis. Microdontia was more frequent in children under 6 years of age at the time of diagnosis (5.7% vs. 0.6%, p < .001). Significant differences were noted between distinct ALL treatment protocols with more common microdontia in patients treated according to the NOPHO ALL2008 protocol. Tooth agenesis was more frequent in patients that underwent therapy according to high-risk arms compared to intermediate- or standard-risk arms (3.8% vs. 1.4%, p = .01). Patients under 6 years of age at diagnosis had a significantly higher average defect index score than older patients (7.0 vs. 2.8, p = .01).

CONCLUSIONS

Children and adolescents who received ALL treatment were at risk for dental damage. Young age and high-intensity therapy were associated with the severity of dental abnormalities.

Investigating prevalence of dental anomalies in Eastern Province of Saudi Arabia through digital orthopantomogram

Objective

The aim of this study was to investigate the prevalence of dental anomalies in the Eastern Province of Saudi Arabia using the digital Orthopantomography (OPG).

Methods

A retrospective radiographic study was performed in which digital OPGs of 1189 subjects, ages ranging between 7 and 65 years were reviewed, and 1104 fulfilled inclusion criteria. Statistical analysis was performed. The OPGs were reviewed for congenitally missing teeth, impactions, ectopic eruption, supernumerary teeth, odontomas, dilacerations, taurodontism, dens in dente, gemination and fusion.

Results

OPGs of 1104 patients with mean age 35.32 ± 16.63 were included. The total prevalence of developmental anomalies in this study was 36.3% (401/1104). Male and female subjects with anomalies were 133 (33.2%) and 268 (66.8%) respectively. The prevalence of dilacerated teeth 300 (30.2%), congenitally missing teeth was 246 (24.7%), supernumerary teeth 18 (1.8%), talon cusp and taurodontism were seen in one patient each 1 (0.1%). Of these, a total of 15 (1.5%) anomalies were noted in pediatric patients.

Conclusions

Dilaceration was the most prevalent anomaly (30.2%) in the studied sample followed by congenitally missing teeth (23.4%). Talon cusp, concrescence/fusion, and taurodontism were the least prevalent anomalies.

The global distribution of permanent canine hypodontia: A systematic review

Objective

To systematically review studies on canine agenesis prevalence in different populations and continents, based on the jaw, sex, location, and associated dental anomalies.

Methods

Electronic and hand searches of English literature in PubMed, Web of Science, Scopus, OpenGrey, and Science Direct were conducted, and the authors were contacted when necessary. Observational studies (population-based, hospital/clinic-based, and cross-sectional) were included. For study appraisal and synthesis, duplicate selection was performed independently by two reviewers. Study quality was assessed using a modified Strengthening the Reporting of Observational Studies in Epidemiology checklist, with main outcome of prevalence of canine agenesis.

Results

The global population prevalence of canine agenesis was 0.30% (0.0-4.7%), highest in Asia (0.54%), followed by Africa (0.33%), and the least in Europe and South America (0.19% in both continents). Canine agenesis was more common in the maxilla (88.57%), followed by both maxilla and mandible (8.57%), and the least common was mandible-only presentation (2.86%). The condition was more common in females (female:male ratio = 1.23), except in Asia (female:male ratio = 0.88) and Africa (female:male ratio = 1). In Asia, unilateral agenesis was almost twice as prevalent as bilateral, but in Europe, the bilateral form was more common.

Conclusions

The overall prevalence of canine agenesis is 0.30%, with the highest prevalence in Asia, followed by Africa, Europe, and South America. The condition is more common in the maxilla than the mandible, and in females than males (except in Asia and Africa), with unilateral agenesis being more common in Asia and the bilateral form showing a greater prevalence in Europe.

Prevalence of Shape-related Developmental Dental Anomalies in India: A Retrospective Study

Aim and objective

The aim and objective of this study was to review the literature to analyze the prevalence of developmental dental anomalies regarding shape in India.

Background

Although there have been several studies investigating the prevalence of individual dental anomalies related to shape, only a few studies considered all subtypes and their distribution among genders, especially in India.

Results

An electronic search was made in the PUBMED database to review prevalence-based data on developmental dental anomalies related to shape in India up to December 2018. A diverse range of results regarding prevalence of developmental dental anomalies related to shape were seen in these studies due to vast regional, cultural, and ethnic diversities and various environmental factors affecting the tooth development.

Conclusion

There is a necessity to conduct more study on shape-related dental anomalies because there are very limited studies regarding prevalence of concrescence, dilacerations, and accessory root and various associated factors.

Clinical significance

Early diagnosis and timely management of these anomalies can prevent complications. The knowledge on identification and prevalence of dental anomalies helps the dental practitioners improve the treatment plan. The prevalence studies can be of utmost importance in the formulation of oral healthcare programs by using their data to analyze the intensity of dental anomalies.

How to cite this article

Goswami M, Bhardwaj S, Grewal N. Prevalence of Shape-related Developmental Dental Anomalies in India: A Retrospective Study. Int J Clin Pediatr Dent 2020;13(4):407–411.

Family-based association study of genetic analysis of paired box gene 9 polymorphisms in the peg-shaped teeth in the Jordanian Arab population

OBJECTIVE

The aim of this study is to genotype thirteen Single Nucleotide Polymorphisms (SNPs) within the paired box gene 9 (PAX9) in 36 Jordanian Arab families with peg-shaped teeth, and also to investigate the association between the PAX9 gene and peg-shaped teeth disorder.

METHODS

Genomic DNA samples were extracted from families according to distinguished processes. Then, DNA was amplified by polymerase chain reaction technique (PCR) using specified primers for the exons of the PAX9 gene. In addition, single nucleotide polymorphisms analysis was conducted using the DNA sequencing genotyping method to identify specific single nucleotide polymorphisms in the PAX9 gene associated with peg-shaped teeth.

RESULTS

Thirteen single nucleotide polymorphisms in the PAX9 gene (Chromosome 14q13.3) were used; seven of them (rs104894467, rs104894469, rs28933373, rs28933970, rs28933971, rs28933972, and rs7143727) were non-polymorphic, and the other six were polymorphic (rs2073244, rs2073246, rs2295222, rs4904155, rs4904210, and rs12881240). Both rs12881240 and rs2295222 SNPs showed significant association with peg-shaped teeth disorder (P < 0.05). Moreover, the haplotype genetic analysis revealed that there is a genetic association with peg-shaped teeth disorder susceptibility (P < 0.05) in the Jordanian families of Arab descent.

CONCLUSION

Our findings exhibited significant variations compared to the data recorded from other countries.

Prevalence and Pattern of Hypodontia among Croatian Orthodontic Patients

Objective

The objective of this retrospective study was to assess the prevalence of hypodontia in the permanent dentition among Croatian orthodontic patients. The occurrence was evaluated concerning gender, specific missing teeth, the location, pattern of distribution in the maxillary and mandibular arches and sagittal and vertical skeletal pattern.

Material and Methods

The sample consisted of 194 patients (75 males and 119 females) from the Department of Orthodontics, Dental Clinic, Clinical Hospital Center Zagreb. Based on the severity of hypodontia the sample was divided into mild (1-2 missing teeth), moderate (3-5 missing teeth) and severe groups (6 or more missing teeth). The location of missing teeth was used to further divide the sample into anterior (intercanine region), posterior (premolars and molars) and anteroposterior groups. In addition, jaw localization of hypodontia was also considered.

Results

Permanent dentition hypodontia among Croatian orthodontic patients was found to be generally mild (80%), and a distribution was similar in the maxilla (39%) and the mandible (41%), as well as in the anterior and posterior segments of dental arch (44%). The number of missing teeth per person ranged from 1 to 12, with no significant difference between genders. The severity and location of hypodontia did not differ significantly between the genders, as well as in between the categories of sagittal and vertical skeletal patterns.

Conclusion

Present results suggest that the treatment plan for patients with hypodontia in permanent dentition should be individualized and adjusted for each case.

Clinical and Epidemiological Study of Supernumerary Teeth in Patients from Plovdiv Region

Abnormalities in the number of teeth are conditions that occur predominantly in childhood. Therefore, monitoring the prevalence and early diagnosis is very important for the timely and appropriate therapeutic approach. The aim of the study was to investigate the incidence of supernumerary teeth in patients from the city of Plovdiv.

Methods and equipment: 1,000 dental patients were studied. Data were collected from patients seeking medical attention at the Faculty of Dental Medicine in Plovdiv. We used clinical, X-ray and statistical methods for investigation.

Results: A 1.1% prevalence of supernumerary teeth (ST) was observed in the studied patients. A statistically significant difference was found between the presence of ST in the permanent and mixed dentition, with a 3% relative proportion of ST in the mixed and 0.62% in the permanent dentition (p < 0.05). The relative proportion of ST in the maxilla was 90.9%, and in the mandible – 9.1%. A statistically significant difference (p < 0.05) was found in the distribution of ST by jaws. In our study, a higher frequency of mesiodens and distomolar (1.08% and 0.22%, respectively) was found in males, and a decreasing relative proportion from the midline to distally in females (mesiodens – 0.56%, paramolar – 0.19%, distomolar – 0.19%).

Conclusion: Supernumerary teeth are a relatively rare dental abnormality in the Bulgarian population. Its distribution by sex and morphology corresponds to the prevalence in Caucasians and populations of southern countries.

Clinical Orodental Anomalies in Taiwanese Children under Age Six: a Study Based on the 1995-1997 National Dental Survey

There are few published studies that report the prevalence of intraoral anomalies for young children. The purpose of this study was to investigate the prevalence and distribution of several congenital oral and paraoral anomalies in Taiwanese children under age six. Twenty-five cities and townships were randomly sampled in different areas of Taiwan using the stratified method. These cities and townships represent cross-sectional samples of geographic locations and socioeconomic levels. A total of 981 Taiwanese children under age six were examined with dental mirrors and explorers as part of the national dental survey. The results of this survey indicated an 11.31% prevalence of geographic tongue. This number is higher than that reported in studies previously performed in different countries. The occurrence of double teeth in primary dentition was found to be 2.14%. Ankyloglossia had a frequency of 1.22%, and primary talon cusp a frequency of 0.61%. Seven (0.71%) children exhibited fissured tongues. Thirteen (1.33%) cases of hypodontia were found. These values were different from those reported in several other countries, which may be attributed to differences in the ethnic and racial composition of the population studied.

Mutations in COL1A1/A2 and CREB3L1 are associated with oligodontia in osteogenesis imperfecta

Background

Osteogenesis imperfecta (OI) is a heterogeneous connective tissue disorder characterized by an increased tendency for fractures throughout life. Autosomal dominant (AD) mutations in COL1A1 and COL1A2 are causative in approximately 85% of cases. In recent years, recessive variants in genes involved in collagen processing have been found. Hypodontia (< 6 missing permanent teeth) and oligodontia (≥ 6 missing permanent teeth) have previously been reported in individuals with OI. The aim of the present cross-sectional study was to investigate whether children and adolescents with OI and oligodontia and hypodontia also present with variants in other genes with potential effects on tooth development. The cohort comprised 10 individuals (7.7–19.9 years of age) with known COL1A1/A2 variants who we clinically and radiographically examined and further genetically evaluated by whole-genome sequencing. All study participants were treated at the Astrid Lindgren Children’s Hospital at Karolinska University Hospital, Stockholm (Sweden’s national multidisciplinary pediatric OI team). We evaluated a panel of genes that were associated with nonsyndromic and syndromic hypodontia or oligodontia as well as that had been found to be involved in tooth development in animal models.

Results

We detected a homozygous nonsense variant in CREB3L1, p.Tyr428*, c.1284C > A in one boy previously diagnosed with OI type III. COL1A1 and COL1A2 were the only two genes among 9 individuals which carried a pathogenic mutation. We found rare variants with unknown significance in several other genes related to tooth development.

Conclusions

Our findings suggest that mutations in COL1A1, COL1A2, and CREB3L1 may cause hypodontia and oligodontia in OI. The findings cannot exclude additive effects from other modifying or interacting genes that may contribute to the severity of the expressed phenotype. Larger cohorts and further functional studies are needed.

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Aim

The primary aim of this study was to evaluate the gender-based differences in patients with hypodontia. As a secondary outcome, the study looked into the correlation between hypodontia and other dental clinical features among Kosovar adolescents.

Material and Methods

3,306 students, aged between 15-21 years were examined in schools in Kosovo. Examinations were performed using a dental mirror to assess the number of teeth present, and dental impressions were taken from hypodontia subjects. Panoramic and periapical radiographs, as well as intraoral photographs, were taken in subjects who were suspected to have hypodontia to verify the diagnosis.

Results

77 of the examined subjects had hypodontia, among which 46 were females (59.7%) and 31 were males (40.3%). The most frequently missing teeth were the maxillary lateral incisors, followed by the mandibular second premolars. 68 patients (88.3%) had at least one dental clinical feature concurrent with hypodontia.

Conclusion

No significant difference was noted in the prevalence of hypodontia according to gender. Teeth rotation was the most commonly observed clinical feature followed by inclination.

Dental anomalies and orthodontic characteristics in patients with pseudohypoparathyroidism

Background

Pseudohypoparathyroidism (PHP) is a rare and inherited disease caused by mutations in the GNAS-gene or upstream of the GNAS complex locus. It is characterized by end-organ resistance to PTH, resulting in hypocalcemia and hyperphosphatemia. We aimed to investigate the dental anomalies according to tooth types and the orthodontic characteristics of patients with PHP.

Methods

Using a cross-sectional design, 29 patients (23 females) with PHP, living in Denmark, were included, and their clinical intraoral photos and radiographs were examined.

Results

Pulp calcification was found in 76% of the patients. Blunting of root apex was present in 55% and shortening of root in 48% of the examined patients. Blunting and shortening of roots were seen more often in premolars than in other tooth types (p_both < 0.01). Crowding of lower anterior teeth was frequently observed (36%) as well as diastema in the upper arch (25%), midline diastema (18%), and Class III malocclusion (11%).

Conclusion

In the present study population, the teeth were frequently affected by pulp calcification and/or deviation of the root morphology. Blunting and shortening of root(s) were more often seen in premolars than in other tooth types. Class III malocclusion was relatively prevalent. It is important to pay attention to dental anomalies and occlusion in order to provide adequate care for patients with PHP.

A case report of multiple bilateral dens invaginatus in maxillary anteriors

The present report presents a case of dens invaginatus (DI) in a patient with 4 maxillary incisors. A 24-year-old female complained of swelling of the maxillary left anterior region and discoloration of the maxillary left anterior tooth. The maxillary left lateral incisor (tooth #22) showed pulp necrosis and a chronic apical abscess, and a periapical X-ray demonstrated DI on bilateral maxillary central and lateral incisors. All teeth responded to a vitality test, except tooth #22. The anatomic form of tooth #22 was similar to that of tooth #12, and both teeth had lingual pits. In addition, panoramic and periapical X-rays demonstrated root canal calcification, such as pulp stones, in the maxillary canines, first and second premolars, and the mandibular incisors, canines, and first premolars bilaterally. The patient underwent root canal treatment of tooth #22 and non-vital tooth bleaching. After a temporary filling material was removed, the invaginated mass was removed using ultrasonic tips under an operating microscope. The working length was established, and the root canal was enlarged up to #50 apical size and obturated with gutta-percha and AH 26 sealer using the continuous wave of condensation technique. Finally, non-vital bleaching was performed, and the access cavity was filled with composite resin.

Dental anomalies in craniofacial microsomia: A systematic review

Objective: To provide an overview on the prevalence and types of dental anomalies in patients with craniofacial microsomia (CFM). Eligibility criteria: Inclusion criteria were CFM and dental anomalies. The following data were extracted: number of patients, methodology, mean age, sex, affected side, severity of mandibular hypoplasia, dentition stage and dental anomalies. Information sources: Cochrane, EMBASE, PubMed, MEDLINE Ovid, Web of Science, CINAHL EBSCOhost and Google Scholar, searched until the 30 August 2019. Risk of bias: The quality was examined with the OCEBM Levels of Evidence. Included studies: In total, 13 papers were included: four retrospective cohort studies, four prospective cohort studies, four case‐control studies and one case series. Synthesis of results: The studies reported information on dental agenesis, delayed dental development, tooth size anomalies, tooth morphology and other dental anomalies. Description of the effect: Dental anomalies are more often diagnosed in patients with CFM than in healthy controls and occur more often on the affected than on the non‐affected side. Strengths and limitations of evidence: This is the first systematic review study on dental anomalies in CFM. However, most articles were of low quality. Interpretation: Dental anomalies are common in CFM, which might be linked to the development of CFM. The pathophysiology of CFM is not entirely clear, and further research is needed.

Prevalence and presentation of hyperdontia in a non-syndromic, mixed Nigerian population

BACKGROUND

Although there have been studies on the prevalence and pattern of hyperdontia in sub-Saharan African subjects with similar cultural backgrounds, based on our search, none have been able to consider these epidemiological parameters in a multiethnic black population, which is expected to add substantial knowledge to what is available.

MATERIAL AND METHODS

This is a retrospective study on the panoramic radiographs of subjects who presented at two dental centres in Abuja, Nigeria between June 2013 and June 2018. Radiographic interpretations were carried out by three independent observers, trained on computer assisted radiographic image interpretation. Data were collected and analyzed using Statistical package for the Social sciences (SPSS) version 22 (IBM Corp, Armonk, USA).

RESULTS

One thousand eight hundred and thirty seven (1837) panoramic radiographs were studied. Subject comprised males and females between ages 12 - 95 years with an average of 35.0 years. The prevalence of unilateral hyperdontia was 1.47% while an occurrence rate of 0.27 was observed for bilateral and multiple hyperdontia. For maxillary hyperdontia, a prevalence of 1.09% was recorded which was significantly more common than the mandibular type (0.65). Of note is that all the supernumerary teeth types were commonly observed in the maxilla except the parapremolar type, with a mandibular occurrence rate of 76.9%.

CONCLUSIONS

From this study, we can conclude that the prevalence of hyperdontia (across different black ethnicities) is low. Although, follicular epithelium around the tooth and root resorption of the enlargement around the adjacent teeth was observed, most were asymptomatic (87.0%) and required no intervention. Key words:Hyperdontia, panoramic radiographs, Sub-Saharan Africa, supernumerary teeth.

Developmental dental anomalies assessed by panoramic radiographs in a Greek orthodontic population sample

PURPOSE

To assess developmental dental anomalies on panoramic radiographs in a Greek orthodontic population.

MATERIALS AND METHODS

The sample consisted of 1200 panoramic radiographs that have been taken as part of routine orthodontic treatment planning in children and adolescents. The following exclusion criteria were applied: systemic disorders such as syndromes or clefts, previous jaw surgery and poor quality of the radiograph. Dental anomalies were classified as anomalies of tooth shape, size, eruption-, position- or number anomalies or root alterations.

RESULTS

The age range of the subjects (536 males and 664 females) was 7-17 years with a mean age of 11.78 years. The prevalence of dental anomalies was assessed with a Chi-squared test. The intraobserver agreement was evaluated by calculating Cohen's [Formula: see text]. Among the 1200 digital panoramic radiographs examined, a total of 224 (18.67%) presented dental anomalies, 92 (7.67%) males and 132 (16.67%) females. Moreover, 203 patients (16.92%) had 1 dental anomaly, whereas 19 (1.58%) and 2 (0.17%) patients had 2 or more than 2 dental anomalies, respectively. Oligodontia was the most prevalent dental anomaly and was presented in 6.4% of the subjects, while supernumerary teeth were detected in 1% of the patients.

CONCLUSIONS

A significant number of orthodontic patients had at least one DDA. The most common DDA in this sample was oligodontia followed by impaction and supernumerary teeth. Comparison to our data with other studies revealed variation in their prevalence suggesting genetic and environmental influences.

The prevalence of malocclusion and orthodontic treatment need in Omani adolescent population

OBJECTIVE:

To determine the prevalence of malocclusion and orthodontic treatment need in a sample of Omani adolescents aged 11–16 years.

MATERIALS AND METHODS:

The total sample included 854 adolescents with 387 boys and 467 girls between the age of 11 and 16 years with no previous orthodontic treatment history. The study design was cross-sectional. The parameters studied were skeletal relationship, lip competency, teeth impactions, missing teeth, contact point displacement, crowding, spacing, incisors and molars classification, overjet, overbite, crossbite, oral hygiene and caries. The Index of Orthodontic Treatment Need (IOTN) was used to study the need for orthodontic treatment for the total sample.

RESULTS:

There was a high prevalence of Class I jaw relationship (86.2%). About 81.6% of the sample studied had Class I molar relationship and 73.8% had Class I incisors relationship. About 61.4% of the sample had no contact displacement, while 5.2% had contact displacement >4 mm. Severe crowding in the maxilla was found in 2.3% while spacing was found in 24.2%. Around 11% of the sample studied had Class II div 1 incisors relationship, 13.5% Class III and only 1.8% had Class II div 2 incisors relationship. Only 8.6% of the sample studied had an overjet >6 mm while 16.3% had a deep bite and 0.2% had anterior open bite of >4 mm. Teeth impaction was found in 11.7% while permanent missing teeth was present in 1.8%. The results showed that 13.9% had a very great need for treatment while 43.2% of the sample did not need any treatment.

CONCLUSION:

Among the Omani adolescents, there was a high prevalence of Class I jaw relations and Class I molar relationship. The prevalence of malocclusion and treatment need in Omanis shows some variation when compared to other ethnicities.

Patterns of congenitally missing teeth of non-syndromic and syndromic patients treated at a single-center over the past thirty years

OBJECTIVES

Literature regarding congenitally-missing-teeth (CMT) is lacking especially on CMT-patterns. Thus, the aim of this study was to present an in-depth analysis of 843 patients with CMT treated at a single-center over the past thirty years.

DESIGN

Age, date-of-birth-year, gender, medical- and family-history, CMT-types, -numbers, -severity, -region, -symmetry, -patterns using the tooth agenesis code (TAC), and -growth types of all clinically and radiographically diagnosed CMT-patients were collected. Age and occurrence of syndromes were used to divide CMT-patients into non-syndromic patients older than nine years (group1) and syndromic CMT-patients (group2). Groups were compared especially regarding gender and CMT-severity.

RESULTS

The average CMT-number per patient was 5.5 (group1, n = 816, 59.9% female) and 15.1 (group2, n = 27, 29.6% female). There were significant less male (40.1% vs. 70.4%, respectively; P = 0.002) as well as significantly less male-oligodontia (44.8% vs. 73.9%, respectively; P = 0.009) in group1 than in group2. Group1 resulted in decreased prevalence of similar CMT-patterns with severity; the most prevalent CMT was the 2^nd premolar; there were no significant differences between the right and left side, whereas more CMT affected the maxilla; the majority of patients presented with bilateral-CMT (82.8%); females were more affected by CMT but more males had severer forms; certain single CMT differed by gender, and CMT was related to first-grade-relatives.

CONCLUSION

The majority of CMT-patients presented with hypodontia. Furthermore, same CMT-patterns seem more like to be present in patients with milder forms of tooth agenesis. Gender-specific association regarding CMT-number, severity groups, and single CMT were detected.

Long-term Dental Anomalies after Pediatric Cancer Treatment in Children

Objective:

The aim of this study is to determine the frequency of dental anomalies (DAs) (microdontia, hypodontia, hyperdontia, enamel defect, root malformation) in pediatric cancer patients at the ages <5 years and between 5 and 7 years, and understand their relationship with the received therapy.

Materials and Methods:

Pediatric patients who were diagnosed with cancer and treated before the age of 7 years were investigated in a case- control design. The study included 93 pediatric patients whose ages at diagnosis were between 9 months and 7 years and whose treatments were completed before 5-8 years. Group A consisted of patients in the age range of 9 months to 4 years and Group B consisted of patients in the age range of 5-7 years. Seventy-two siblings with compatible dental age ranges were included in the control group. For both groups, intraoral examinations were performed and panoramic radiographs were taken.

Results:

Among the 93 pediatric patients, the mean age was 9.54±1.25 (range: 8-13 years) and 48 (51.6%) patients were male. The most common diagnosis was hematologic malignancy with a rate of 65.5%. At least one DA was detected in 7 (9.7%) individuals of the control group and in 78 (83.9%) of the patient group. While the patients in the study group had all kinds of DAs, those in the control group had only enamel defects. The rates of microdontia (p=0.077) and hypodontia (p=0.058) were detected to be significantly higher in Group A than in Group B. Root malformation was more common in patients receiving chemotherapy and radiotherapy than in those receiving only chemotherapy (p=0.006).

Conclusion:

In this study it was found that the pediatric patients who received cancer treatment before the age of 7 years constituted a high-risk group for DAs. The frequencies of microdontia and hypodontia were increased even more when the patient was treated for cancer before 5 years of age.

Investigation of SOSTDC1 gene in non-syndromic patients with supernumerary teeth

Background

The etiology of supernumerary teeth is still unclear however heredity is believed to be a major factor and this idea was supported by several case reports. Recently, a relationship between supernumerary tooth formation and deficiency of Uterine Sensitization Associated Gene-1 (Usag-1), a rat gene that is expressed in sensitized endometrium, was reported in mice. The human homolog gene for Usag-1, Sclerostin Domain Containing 1 (SOSTDC1), shows 85% identity with mouse Usag-1. The present study aimed to investigate SOSTDC1 coding regions in non-syndromic patients with one or more supernumerary teeth.

Material and Methods

Twenty-five non-syndromic patients (21 male and 4 female) aged 5-15 years, with one or more supernumerary teeth were included in the study. Saliva samples were collected from patients and DNA samples were isolated and analyzed using PCR.

Results

Eight phenotypes of supernumerary tooth formation were observed in the study. From the DNA analysis, 2 novel and 3 previously identified sequence alterations were identified however, in investigating the Usag-1 homolog SOSTDC1 gene, the present study could not find any phenotype-genotype relationship.

Conclusions

There are many SOSTDC1 homolog genes in the human genome and future studies should investigate these candidate genes. Also studies in larger case groups including family members may reveal the hereditary pattern.

Key words:Genetics, Usag-1, mesiodens, DNA sequencing, pediatric dentistry, PCR.

Dentinogenesis imperfecta type II in Swedish children and adolescents

Background

Dentinogenesis imperfecta (DGI) is a heritable disorder of dentin. Genetic analyses have found two subgroups in this disorder: DGI type I, a syndromic form associated with osteogenesis imperfecta (OI), and DGI type II, a non-syndromic form. The differential diagnosis between types I and II is often challenging. Thus, the present cross-sectional study had two aims: to (i) investigate the prevalence and incidence of DGI type II among Swedish children and adolescents and (ii) search out undiagnosed cases of DGI type I by documenting the prevalence of clinical symptoms of OI in these individuals. We invited all public and private specialist pediatric dental clinics (n = 47) in 21 counties of Sweden to participate in the study. We then continuously followed up all reported cases during 2014−2017 in order to identify all children and adolescents presenting with DGI type II. Using a structured questionnaire and an examination protocol, pediatric dentists interviewed and examined patients regarding medical aspects such as bruising, prolonged bleeding, spraining, fractures, hearing impairment, and family history of osteoporosis and OI. Joint hypermobility and sclerae were assessed. The clinical oral examination, which included a radiographic examination when indicated, emphasized dental variables associated with OI.

Results

The prevalence of DGI type II was estimated to be 0.0022% (95% CI, 0.0016–0.0029%) or 1 in 45,455 individuals. Dental agenesis occurred in 9% of our group. Other findings included tooth retention (17%), pulpal obliteration (100%), and generalized joint hypermobility (30%). Clinical and radiographic findings raised a suspicion of undiagnosed OI in one individual, a 2-year-old boy; he was later diagnosed with OI type IV.

Conclusions

These results show a significantly lower prevalence of DGI type II than previously reported and point to the importance of excluding OI in children with DGI.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0887-2) contains supplementary material, which is available to authorized users.

Dental Number Anomalies and Their Prevalence According To Gender and Jaw in School Children 7 To 14 Years

OBJECTIVES

This study aimed to find the prevalence of Hypodontia and Hyperdontia in different ethnicities in patients from 7 to 14 years old.

MATERIAL AND METHODS

A group of 520 children were included aged 7 to 14 years, only the children who went to primary schools. Controls were performed by professional people to preserve the criteria of orthodontic abnormalities evaluation. The data were recorded in the individual card specially formulated for this research and all the patients suspected for hypodontia and hyperdontia the orthopantomography for confirmation was made. The data were analysed using descriptive statistical analysis using χ² test for the significant difference for p ˂ 0.05 and Fisher test for p < 0.05.

RESULTS

Hypodontia, not counting the patients with missing third molars was found in 18 patients researched or 3.46%. The most commonly missing teeth were the second lower premolars, the second upper premolars, second upper lateral incisors followed by the lower incisors. Hyperdontia not including the third molars was found in 4 cases of the participants or 0.76% from which the most frequent atypical tooth mesiodens and one case of bilateral hypodontia of a lateral upper incisor with typical shape and size. But there were no significant differences when tested between genders and jaws.

CONCLUSION

The prevalence we found is similar to the prevalence in the region. Our findings indicate that there is a difference between the genders in the prevalence of hypodontia, but without statistical significance, while for hyperdontia we can't see such a difference between the sexes.

Prevalence of Taurodont Molars in a Selected Iranian Adult Population

Introduction:

Taurodontism is an anomaly characterized by elongated crowns and consumedly apical location of the bifurcation area. This study aimed to determine the prevalence of taurodontism in molars based on digital panoramic radiographies in eight cities of Iran.

Methods and Materials:

This descriptive cross-sectional study was conducted on 2360 digital panoramic radiographs taken for different treatment purposes. Demographic information of patients was recorded and radiographs were evaluated for presence of taurodont molars. The prevalence rates were calculated and the data were analyzed using SPSS software version 18 via paired t-test, chi square test and ANOVA.

Results:

A total of 2360 panoramic radiographs (from 51.4% male and 48.6% female patients) were evaluated and the prevalence of taurodontism was reported 22.9% (22.6% in males and 23.3% in females) (P>0.05). Its prevalence was 51.67% in the right and 48.33% in the left quadrants (P>0.05), 34.1% in the mandible and 65.9% in the maxilla (P=0.000) and 79.52% in the second and 20.48% in the first molar (P=0.000). The prevalence of hypotaurodontism, mesotaurodontism and hypertaurodontism was 84.13%, 11.07% and 4.8%, respectively.

Conclusion:

The prevalence of taurodont molars was high in Iran and it was more common in the second molars and in the maxilla. Hypotaurodontism had the highest prevalence.

A novel mutation of adenomatous polyposis coli (APC) gene results in the formation of supernumerary teeth

Supernumerary teeth are teeth that are present in addition to normal teeth. Although several hypotheses and some molecular signalling pathways explain the formation of supernumerary teeth, but their exact disease pathogenesis is unknown. To study the molecular mechanisms of supernumerary tooth‐related syndrome (Gardner syndrome), a deeper understanding of the aetiology of supernumerary teeth and the associated syndrome is needed, with the goal of inhibiting disease inheritance via prenatal diagnosis. We recruited a Chinese family with Gardner syndrome. Haematoxylin and eosin staining of supernumerary teeth and colonic polyp lesion biopsies revealed that these patients exhibited significant pathological characteristics. APC gene mutations were detected by PCR and direct sequencing. We revealed the pathological pathway involved in human supernumerary tooth development and the mouse tooth germ development expression profile by RNA sequencing (RNA‐seq). Sequencing analysis revealed that an APC gene mutation in exon 15, namely 4292‐4293‐Del GA, caused Gardner syndrome in this family. This mutation not only initiated the various manifestations typical of Gardner syndrome but also resulted in odontoma and supernumerary teeth in this case. Furthermore, RNA‐seq analysis of human supernumerary teeth suggests that the APC gene is the key gene involved in the development of supernumerary teeth in humans. The mouse tooth germ development expression profile shows that the APC gene plays an important role in tooth germ development. We identified a new mutation in the APC gene that results in supernumerary teeth in association with Gardner syndrome. This information may shed light on the molecular pathogenesis of supernumerary teeth. Gene‐based diagnosis and gene therapy for supernumerary teeth may become available in the future, and our study provides a high‐resolution reference for treating other syndromes associated with supernumerary teeth.

Systematic development of esthetics and function in a young patient with maxillary dental aplasia

OBJECTIVES

Full-arch rehabilitations in young patients suffering from dental agenesis should compensate for the reduced vertical dimension of occlusion and restore both esthetics and function at minimal biological cost. This requires precise planning and maximum patient compliance during the preprosthetic phase. The pretreatment period with tooth-colored splints promotes a predictable outcome of the final restorations. Clinical considerations: Thanks to better restorative materials and adhesive techniques and increased knowledge of how to preserve sound tooth structures, prosthetic dentistry has increasingly turned toward minimally invasive procedures. The present clinical case documents a minimally/non-invasive maxillary full-arch rehabilitation of an agenesis patient with multiple dental aplasia, primary tooth persistence, and deficits in bone growth. The patient was pretreated with a tooth-colored CAD/CAM polycarbonate splint. Adequate esthetics and function were achieved by two zirconia-based single-wing adhesive fixed dental prostheses to replace the upper lateral incisors, lithium disilicate ceramic partial crowns for the posterior regions, and two feldspathic veneers for the upper central incisors.

CONCLUSIONS

Non-invasive pretreatment with a removable tooth-colored splint realizes the treatment goal simply and safely, reduces treatment time, increases predictability, and facilitates the transfer of the prototype to the final restorations. New restorative options permit the minimally invasive treatment of such patients.

CLINICAL SIGNIFICANCE

A pretreatment with a removable tooth-colored splint offers a simple and safe way to define the treatment goal, reduces treatment time, increases predictability, and facilitates the transfer of the results to the final restorations even in complex cases. New restorative options permit minimally invasive treatments of young patients with multiple dental agenesis.

Mutations in COL1A1 and COL1A2 and dental aberrations in children and adolescents with osteogenesis imperfecta - A retrospective cohort study

Osteogenesis imperfecta (OI) is a heterogeneous group of disorders of connective tissue, caused mainly by mutations in the collagen I genes (COL1A1 and COL1A2). Dentinogenesis imperfecta (DGI) and other dental aberrations are common features of OI. We investigated the association between collagen I mutations and DGI, taurodontism, and retention of permanent second molars in a retrospective cohort of 152 unrelated children and adolescents with OI. The clinical examination included radiographic evaluations. Teeth from 81 individuals were available for histopathological evaluation. COL1A1/2 mutations were found in 104 individuals by nucleotide sequencing. DGI was diagnosed clinically and radiographically in 29% of the individuals (44/152) and through isolated histological findings in another 19% (29/152). In the individuals with a COL1A1 mutation, 70% (7/10) of those with a glycine substitution located C-terminal of p.Gly305 exhibited DGI in both dentitions while no individual (0/7) with a mutation N-terminal of this point exhibited DGI in either dentition (p = 0.01). In the individuals with a COL1A2 mutation, 80% (8/10) of those with a glycine substitution located C terminal of p.Gly211 exhibited DGI in both dentitions while no individual (0/5) with a mutation N-terminal of this point (p = 0.007) exhibited DGI in either dentition. DGI was restricted to the deciduous dentition in 20 individuals. Seventeen had missense mutations where glycine to serine was the most prevalent substitution (53%). Taurodontism occurred in 18% and retention of permanent second molars in 31% of the adolescents. Dental aberrations are strongly associated with qualitatively changed collagen I. The varying expressivity of DGI is related to the location of the collagen I mutation. Genotype information may be helpful in identifying individuals with OI who have an increased risk of dental aberrations.

Prevalence and distribution of selected dental anomalies among saudi children in Abha, Saudi Arabia

BACKGROUND

Dental anomalies are not an unusual finding in routine dental examination. The effect of dental anomalies can lead to functional, esthetic and occlusal problems. The Purpose of the study was to determine the prevalence and distribution of selected developmental dental anomalies in Saudi children.

MATERIAL AND METHODS

The study was based on clinical examination and Panoramic radiographs of children who visited the Pediatric dentistry clinics at King Khalid University College of Dentistry, Saudi Arabia. These patients were examined for dental anomalies in size, shape, number, structure and position. Data collected were entered and analyzed using statistical package for social sciences version.

RESULTS

Of the 1252 children (638 Boys, 614 girls) examined, 318 subjects (25.39%) presented with selected dental anomalies. The distribution by gender was 175 boys (27.42%) and 143 girls (23.28%). On intergroup comparison, number anomalies was the most common anomaly with Hypodontia (9.7%) being the most common anomaly in Saudi children, followed by hyperdontia (3.5%). The Prevalence of size anomalies were Microdontia (2.6%) and Macrodontia (1.8%). The prevalence of Shape anomalies were Talon cusp (1.4%), Taurodontism (1.4%), Fusion (0.8%).The prevalence of Positional anomalies were Ectopic eruption (2.3%) and Rotation (0.4%). The prevalence of structural anomalies were Amelogenesis imperfecta (0.3%) Dentinogenesis imperfecta (0.1%).

CONCLUSIONS

A significant number of children had dental anomaly with Hypodontia being the most common anomaly and Dentinogenesis imperfecta being the rare anomaly in the study. Early detection and management of these anomalies can avoid potential orthodontic and esthetic problems in a child. Key words:Dental anomalies, children, Saudi Arabia.

Radiographic Study of the Prevalence and Distribution of Hypodontia Associated with Unilateral and Bilateral Clef Lip and Palate in a Hungarian Population

Background

Cleft defects are one of the most frequent birth-deformities of the orofacial region and they are commonly associated with anomalies of the tooth structure, size, shape, formation, eruption, and tooth number. The aim of our study was to evaluate the prevalence, distribution, and potential association of combined hypodontia in cleft-affected patients with regard to all types of teeth in both jaws in the permanent dentition.

Material/Methods

This retrospective radiographic analysis included patients with various types of clefts treated orthodontically in the Department of Orofacial Orthopedics and Orthodontics at Heim Pàl Children’s Hospital, Budapest. There were 150 patients (84 males, 66 females) with non-syndromic unilateral (UCLP; n=120 patients) or bilateral (BCLP; n=30 patients) cleft formation (lip, alveolus and palate) who met the inclusion criteria. Statistical analysis was performed using the chi-square test and Fisher’s exact test (significance level p<0.05).

Results

Hypodontia was significantly more frequent in patients with cleft-sided lateral incisor (104 patients, 69%), with a total of 235 missing teeth, followed by the second premolars of the upper and lower jaw. A significant correlation of congenital missing teeth was observed in left-sided clefts between the upper and lower second premolar in the cleft area.

Conclusions

Hypodontia inside and outside the cleft area was frequently observed. This should affect the therapy plans, especially if the cleft-sided premolar is also absent. Further comprehensive research including numerous random samples is necessary for better estimating other possible associations.

Tooth Size in Patients with Mild, Moderate and Severe Hypodontia and a Control Group

Objectives:

To compare tooth size between subjects with mild, moderate and severe hypodontia and a control group.

Material and Methods:

The study comprised 120 patients with hypodontia divided into three groups of 40 mild (≤2 teeth congenitally missing), 40 moderate (3-5 teeth congenitally missing) and 40 severe (≥6 teeth congenitally missing) hypodontia; and 40 age and sex matched controls. Tooth size was recorded by measuring the mesiodistal and buccolingual dimensions of all fully erupted teeth on study models using digital callipers and compared between all hypodontia and control groups using Two-way ANOVA and Post Hoc Tests of subgroup comparison.

Results:

Two-way ANOVA revealed patients with hypodontia had significantly smaller mesiodistal and buccolingual tooth dimensions compared with controls (p<0.05). Furthermore patients with more severe hypodontia demonstrated significantly smaller tooth dimensions than those in the mild and moderate hypodontia subgroups (p<0.05). The most affected tooth in terms of tooth size reduction was the maxillary lateral incisor and the least affected tooth was the mandibular first molar.

Conclusion:

Patients with hypodontia have smaller tooth dimensions than control. Tooth size appears to be affected by the degree of hypodontia, with severe hypodontia having a greater effect on tooth size reduction. The findings of this study may contribute to understanding the aetiology of hypodontia and aid the multidisciplinary management of this complex condition.