"Examining the link between tooth agenesis and papillary thyroid cancer: is there a risk factor?" Observational study.

BACKGROUND: Mutations in one or multiple genes can lead to hypodontia and its characteristic features. Numerous studies have shown a strong genetic influence on the occurrence of hypodontia, and identified several genes, including AXIN2, EDA, FGF3, FGFR2, FGFR10, WNT10A, MSX1, and PAX9, that are directly associated with dental agenesis and carcinogenesis. The objective of this study was to investigate the occurrence and pattern of tooth agenesis, microdontia, and palatally displaced canine (PDC) in women diagnosed with papillary thyroid cancer (PTC), compared to a control group of women without any malignancy or thyroid disease. MATERIALS AND METHODS: This case-control study was carried at the Department of Orthodontics, School of Dental Medicine University of Zagreb, and Department of Oncology and Nuclear Medicine Sestre Milosrdnice University Hospital Centre. The study involved a clinical examination and evaluation of dental status, panoramic X-ray analysis, and assessment of medical and family history of 116 female patients aged 20-40 with PTC, as well as 424 females in the control group who were of similar age. RESULTS: The prevalence of hypodontia, microdontia, and PDC was statistically higher in women with PTC than in the control group. The prevalence rate of hypodontia was 11.3% in the experimental group and 3.5% in the control group. The experimental group showed a higher occurrence of missing upper lateral incisors, lower left central incisors, and all the third molars (except the upper left) compared to the control group. Women with PTC showed the prevalence of PDC significantly higher than the control group (3.5%, 0.7%, p = 0.002). The probability of hypodontia as a clinical finding increases 2.6 times, and microdontia occurs 7.7 times more frequently in women with PTC. CONCLUSION: Our study suggests a possible link between odontogenesis and PTC. The absence of permanent teeth may increase the likelihood of PTC in women. Leveraging the age-7 orthopantomogram to identify women at high risk for PTC within a critical early detection window could significantly improve oral health outcomes and PTC prognosis through proactive interventions.

Agenesis of the permanent teeth in sub-Saharan Africans: Prevalence, patterns, interpretations.

OBJECTIVE: Dental agenesis data in modern and premodern sub-Saharan Africans are presented by region, West, Central, East, and South, and by sex. Beyond characterizing the anomaly, comparisons are made with other populations and future work is encouraged. The findings should be of use to dental clinicians and anthropologists. METHODS: Agenesis of the UI2, LI1, UP2, LP2, UM3, and LM3 was recorded in 52 discrete samples of mainly skeletal dentitions (n = 2162) from across the subcontinent. After dividing into temporal categories, regional pooling was effected for adequate sample sizes across the vast geographic area. Only adults were included to record M3 status. Analyses included 95% confidence intervals and chi-square comparisons by region and sex. RESULTS: Of 1668 modern individuals 2.3% have UI2-LP2 agenesis (CI 1.6-3.1%). Regional and sex differences are non-significant, though females are most affected. For M3s it is 7.0% (5.7-8.4%), with the Central region sample differing significantly from the East and South. Females again have greater prevalence, with the difference in the West significant. UI2-LP2 agenesis affects 0.6% of 494 premodern individuals (0.1-1.8%), while M3 agenesis is 8.5% (6.1-11.5%). None of these differences are significant. CONCLUSIONS: Rates are toward the low end of global ranges, including 0.0-12.6% for UI2-LP2 from case reports, and 5.3-56.0% for M3 agenesis. With exceptions, generally insignificant inter-region differences imply that rates reasonably represent sub-Saharan peoples overall. Results will be of interest to anthropologists, but those related to risk factors, patterning, and prevalence may assist clinicians in tailoring treatment, while informing patients how this anomaly differs by population ancestry.

Clinical analysis of nonsyndromic oligodontia phenotypes.

OBJECTIVES: To provide references, this study investigated the clinical characteristics of patients with nonsyndromic oligodontia. METHODS: The information of 178 patients with oligodontia was collected, including histories, oral examinations, and panoramic radiographs. Tooth agenesis characteristics were calculated and evaluated. All the data were statistically analyzed with SPSS 24.0 software. RESULTS: No significant difference in the number of missing teeth was found between sexes nor between the right and left sides, and congenitally missing teeth affected the maxillary arch (P<0.05). The highest prevalence of tooth agenesis was observed in the mandibular second premolars. In the maxillary arch, the most common pattern of tooth agenesis was agenesis of the bilateral first and second premolars. The agenesis of the bilateral second premolars was observed in the mandibular arch. The prevalence of a symmetric pattern between the right and left quadrants was significantly higher than that of matched patterns between the maxillary and mandibular antagonistic quadrants. Approximately 16.85% of patients with nonsyndromic oligodontia were affected by other tooth-related anomalies. CONCLUSIONS: The common patterns of tooth agenesis were successfully identified in patients with nonsyndromic oligodontia. Dentists need to provide multidisciplinary treatments for patients with nonsyndromic oligodontia because of variations in occluding and full-mouth tooth agenesis patterns.

Patterns and sexual dimorphism of non-syndromic hypodontia among a French orthodontic population.

OBJECTIVES: This retrospective study aimed to estimate the prevalence of non-syndromic congenitally missing teeth (CMT) and to explore the frequency of CMT patterns in a French orthodontic population. In addition, the study sought to assess sex-based differences in CMT patterns. DESIGN: Panoramic radiographs of 4569 orthodontic patients between 9 and 21 years-old performed over a 16-year period (2006-2022) were examined to identify non-syndromic tooth agenesis, excluding third molars. A chi-square test or a Fisher exact test were used to determine the difference in the prevalence of tooth agenesis between sex and between arches. RESULTS: Tooth agenesis was observed in 7.3% of the sample (7.9% for females and 6.6% for males). Approximately 86% of the included subjects presented 1 or 2 missing teeth. Single tooth agenesis was significantly more frequent in females than males (p = 0.002, χ2). In total, 23 of the 67 different patterns of CMT observed, were present more than once. 75.5% of male patients and 79.5% of female patients presented one or both missing lateral incisors or second premolars, rarely affected at the same time. This study showed no sex difference in the patterns of tooth agenesis. LIMITATIONS: This study has limitations due to its retrospective nature and our findings apply solely to an orthodontic population from a white ethnic background. CONCLUSIONS: Clinicians should be aware of this particular incisor/premolar phenotype regardless of biological sex. Issues associated with congenitally missing teeth can be managed more effectively with early teenage diagnosis.

Associations across 22 dental and craniovertebral anomalies or variations, sagittal skeletal relationships, and vertical growth patterns: a comprehensive epidemiological study of 43 dentoskeletal traits.

INTRODUCTION: Despite researchers' recent interest in identifying links between some dental and craniovertebral abnormalities, there are many important, unassessed gaps in our knowledge of this matter. In addition, previous samples were small. This large study aimed to examine, for the first time, the occurrence/severity of numerous dental and skeletal anomalies or variations and their correlations with each other and with growth patterns. METHODS: This epidemiological study was conducted on pretreatment radiographs of 1194 patients from 3 cities (815 females). Skeletal sagittal skeletal relationships and vertical growth patterns were determined. The occurrence/severity were assessed for: cervical vertebral fusion (CVF), atlas posterior arch deficiency (APAD), ponticulus posticus (PP), sella turcica bridging (STB), hypodontia, oligodontia, hyperdontia, missing of maxillary laterals, microdontia, macrodontia, root dilaceration, odontoma, taurodontism, dental fusion, dental gemination, enamel pearl, permanent molar ankylosis, primary molar ankylosis, dens in dente, dens invaginatus, dental impaction, ectopic eruption, and dental transposition. Incidental findings were recorded as well. Concurrent anomalies, sex dimorphism, and correlations across variables were examined statistically, adjusting for the false discovery rate (α = 0.05). RESULTS: Prevalence was calculated for 43 dentoskeletal traits/anomalies (22 abnormalities/variations [plus their severities/types] as well as 21 incidentally found traits/anomalies). Dental impaction may be more common in hyperdivergent and severer cases of sella bridging; also, primary molar ankylosis was associated with missing teeth. Dental impaction was associated only with STB and not with PP, APAD, or vertebral fusion. The only association observed among the four skeletal anomalies was seen between APAD and CVF. Merely the variables 'sagittal skeletal relationships, vertical growth patterns, PP, and APAD' showed sexual dimorphism; of these, only vertical growth pattern and APAD remained sexually dimorphic after adjusting for the FDR; still, the other two remained marginally significant and worth further evaluations. Sex dimorphism did not exist in concurrent abnormalities. The skeletal Class III was associated with the concurrent occurrence of craniovertebral, dental, and dentoskeletal abnormalities. Skeletal Class I was associated with fewer occurrences of concurrent dental anomalies. Vertical growth patterns were not associated with concurrent dental or dentoskeletal anomalies. However, the hyperdivergent pattern was associated with fewer cases of concurrent craniovertebral abnormalities. CONCLUSIONS: STB and hyperdivergent pattern were associated with dental impaction. However, APAD, CVF, or PP were not associated with dental impaction. APAD was associated with CVF. Sexual dimorphism existed conclusively in the case of vertical growth patterns and APAD. Concurrent abnormalities (dental, skeletal, and dentoskeletal) were associated with skeletal Class III.

Is there an association between molar incisor hypomineralization and developmental dental anomalies? A case-control study.

BACKGROUND: The aim of this study was to determine whether there is any association between molar incisor hypomineralization and developmental dental anomalies. METHODS: Two pediatric dentists evaluated panoramic radiographs of 429 children aged 8-14 years with molar incisor hypomineralization (study group) and 437 children without molar incisor hypomineralization (control group) in terms of developmental dental anomalies. Twelve different developmental dental anomalies were categorized into four types: size (microdontia, macrodontia); position (ectopic eruption of maxillary permanent first molars, infraocclusion of primary molars); shape (fusion, gemination, dilaceration, taurodontism, peg-shaped maxillary lateral incisors); and number (hypodontia, oligodontia, hyperdontia) anomalies. RESULTS: No significant difference was observed in the frequencies of developmental dental anomalies between the study and control groups in total, females, and males (p > 0.05). A statistically significant difference was found between the distribution of developmental size, position, shape, and number anomalies between the study and control groups (p = 0.024). The most common anomaly in both groups was hypodontia (6.3% and 5.9%, respectively). There was a significant difference between the study and control groups in terms of subtypes of shape anomaly in all children and females (p = 0.045 and p = 0.05, respectively). CONCLUSIONS: While a significant difference was observed between the distributions of types of developmental dental anomalies between individuals with and without molar incisor hypomineralization, there was no difference in terms of the frequency of developmental dental anomalies.

Status of retained deciduous second molars in subjects with agenesis of second premolars in relation to age.

AIM: To evaluate the presence and status of retained DM2 without permanent successors in relation to age. BACKGROUND: Preservation of retained deciduous second molars (DM2) can be applied to treat congenital absence of second premolars (PM2). However, the consequences of caries and progressing root resorption or infraocclusion may affect their survival. METHODS: Panoramic radiographs of individuals >10 years of age with agenesis of at least one PM2 were evaluated and divided into three groups according to age. The presence and location of retained DM2, caries/restorations, infraocclusion and root resorption were investigated. RESULTS: A total of 131 subjects with PM2 agenesis were included (mean age: 13 years 11 months). The majority were missing one or two PM2. In total, 174 retained DM2 were present (33%), and their incidence was higher in the younger age groups. Caries/restorations were found in 88 (50.6%) and infraocclusion in 21 (12%) retained DM2. The roots were resorbed mostly for ½ of the root length (35%). CONCLUSION: Long-term prognosis of retained DM2 without permanent successors seems uncertain, especially within the younger age group. In individuals older than 17 years, the prognosis for a healthy DM2 is favorable, if no distinct infraocclusion or extensive root resorption is present.

Phenotypic characteristics of taurodontism and a novel WNT10A variant in non-syndromic oligodontia family.

OBJECTIVE: Variants in wingless-type MMTV integration site family member 10A (WNT10A) have been proposed to be the most common cause of non-syndromic oligodontia (NSO). The goal of the present study was to identify the novel WNT10A variants in Chinese families with NSO. DESIGN: Clinical data were collected from 39 families with oligodontia admitted to the Hospital of Stomatology Hebei Medical University (China) from 2016 to 2022. Whole-exome sequencing (WES) and Sanger sequencing were performed to identify WNT10A variants in three families with non-syndromic oligodontia. Amino acid conservation analysis and protein conformational analysis were conducted for the WNT10A variant. Genotype-phenotype analysis was performed on the previously reported WNT10A variants related to NSO. RESULTS: We found a novel heterozygous WNT10A variant c.1127 G>A (p.Cys376Tyr) and two reported heterozygous variants c.460 C>A (p.Leu154Met) and c.511 C>T (p.Arg171Cys). Structural modeling showed that the novel WNT10A variant was located in a highly conserved domain, which led to structural damage of WNT10A protein. In addition, we found that the phenotype of the WNT10A variants affected the maxillary second premolars, followed by the mandibular second premolars, and rarely affected the maxillary central incisor. Herein, it is the first time to report that NSO patients with WNT10A monoallele mutation carry taurodontism phenotype and 6.1% prevalence of taurodontism in WNT10A-related NSO patients. CONCLUSIONS: Our results demonstrated that the novel variant c.1127 G>A (p.Cys376Tyr) of WNT10A causes NSO. The present study expanded the known variation spectrum of WNT10A and provided valuable information for genetic counseling of families.

A comparative retrospective study on the prevalence and therapeutic treatment of dental agenesis between healthy children and children with systemic disease or congenital malformation.

BACKGROUND: Dental agenesis (DA) in the permanent dentition is one of the most common dental anomalies, with a prevalence up to 2-10%. Therefore, the aim of this retrospective study was to investigate the prevalence and therapeutic treatment of DA in healthy children (HC) compared to children with systemic disease or congenital malformation (SD/CM). METHODS: Out of 3407 patients treated at the Department of Paediatric Dentistry of the Justus Liebig University Giessen (Germany) between January 2015 and December 2020, a total of 1067 patients (594 female, 473 male) aged between 4.5 and 18 years were included in this study due to DA. Besides the patients' general medical history and therapeutic treatments, panoramic radiographs were analysed. RESULTS: In contrast to the HC group with 9.7% DA, the SD/CM group showed a significantly higher prevalence of DA (19.8%; p < 0.05). The latter group was further classified into children with ectodermal dysplasia (4.4%), down syndrome (8.2%), cleft lip and palate (4.4%), intellectual disability/developmental delay (16.4%), and other genetic/organic diseases without intellectual disability (45.9%). Regarding therapeutic treatments, the HC group (59.5%) was significantly more often treated with an orthodontic gap opening compared to the SD/CM group (42.6%; p < 0.05), followed by orthodontic gap closing 36.5% in the HC group and 22.9% in the SD/CM group (p < 0.05), whereas no treatment was predominantly performed in the SD/CM group (37.7%) compared to the HC group (4%; p < 0.05). Furthermore, 50% in the SD/CM group required general anaesthesia for therapeutic treatment (vs. 8.1% in the HC group; p < 0.05). CONCLUSIONS: Children with SD/CM suffered more often from DA compared to HC that underlines multi- and interdisciplinary treatment of utmost importance. Furthermore, due to intellectual disability, common treatment methods can be complicated by insufficient compliance. This fact underlines the importance of an early attempt to establish the necessary cooperation enabling children with SD/CM to receive therapy.

Analysis of congenital deciduous teeth absence and its permanent teeth phenotype.

OBJECTIVES: This study aimed to investigate the clinical characteristics of congenital deciduous teeth absence and its permanent teeth performance type by using panoramic radiographs. METHODS: A total of 15 749 panora-mic radiographs of 3-6-year-old children with deciduous dentition were collected from January 2020 to December 2021. The incidence of congenital deciduous teeth absence was observed, and the abnormality of permanent teeth was recor-ded. SPSS 24.0 software was used for statistical analysis. RESULTS: The incidence of congenital deciduous teeth absence was 2.54% (400/15 749), which was found in 217 girls and 183 boys, and the difference between the genders was statistically significant (P=0.003). The absence of one and two deciduous teeth accounted for 99.75% (399/400) of the subjects. In addition, 92.63% (490/529) of mandibular deciduous lateral incisor was congenitally absent, 44.80% (237/529) of deciduous teeth was absent in the left jaw, and less than 55.20% (292/529) was absent in the right; the difference between them was statistically significant (P=0.017). The absence of 96.41% (510/529) deciduous teeth in the mandibular was significantly more than that of 3.59% (19/529) in the maxillary, and the difference between was statistically significant (P=0.000). Furthermore, 68.00% (272/400) and 32.00% (128/400) of deciduous teeth were absent in unilateral and bilateral, respectively, and the difference was statistically significant (P=0.000). Four types of congenital deciduous teeth absence with permanent teeth were observed as follows: 1) 73.91% (391/529) of permanent teeth was absent; 2) 20.60% (109/529) of permanent teeth was not absent; 3) the number of fused permanent teeth accounted for 4.91% (26/529); 4) the number of supernumerary teeth was 0.57% (3/529). CONCLUSIONS: Although the absence of congenital deciduous teeth is less common than that of permanent teeth, it affects deciduous and permanent teeth to some extent. Dentists should pay attention to trace and observe whether abnormalities are present in the permanent teeth and take timely measures to maintain children's oral health.

Association of congenitally missing teeth with adult temporomandibular disorders in the urban health checkup population.

BACKGROUND: Congenitally missing tooth is the most common dental abnormality which leaves spaces in the arch, leads to numerous forms of malocclusion due to the Bolton index discrepancy and is even associated with abnormal craniofacial morphology. Even though the roles of malocclusion and tooth loss in temporomandibular disorders (TMD) development remain controversial, basic researches have found some common molecules are involved in osteoarthritis and dental agenesis. However, the association of congenitally missing teeth with TMD is unknown. We hence investigated the association of congenitally missing teeth with TMD. METHODS: A cross-sectional analysis of 586 control participants (male: 287, female: 299, 38.33 ± 11.65 years) and 583 participants with non-third molar congenitally missing teeth (male: 238, female: 345, 39.13 ± 11.67 years) who consecutively received routine dental and TMD checkup according to Diagnostic Criteria for Temporomandibular Disorders Axis I in Health Management Center, Xiangya Hospital was performed. Logistic regression analysis was used to study the association of congenitally missing teeth with TMD. RESULTS: The congenitally missing teeth group included 581 hypodontia and 2 oligodontia participants. The congenitally missing anterior teeth participants, the congenitally missing posterior teeth participants and participants with both congenitally missing anterior and posterior teeth accounted for 88.34%, 8.40% and 3.26% of the congenitally missing teeth group respectively. Congenitally missing teeth group had greater ratios of females and orthodontic history. Participants with congenitally missing teeth had a significantly higher prevalence of overall TMD (67.24%) in comparison to control participants (45.90%). After adjusting age, gender, presence of congenitally missing teeth, number of congenitally missing teeth, number of non-congenitally missing teeth, number of dental quadrants with missing teeth, visible third molar and orthodontic history, the variables of age, gender, presence of congenitally missing teeth and number of dental quadrants with missing teeth were significant for overall TMD. Multivariable logistic regression analysis showed congenitally missing tooth was significantly related with overall TMD [odds ratio (OR):1.689(1.080-2.642), P = 0.022], intra-articular TMD [OR: 1.711(1.103-2.656), P = 0.017] and pain-related TMD [OR: 3.093(1.321-7.239), P = 0.009]. CONCLUSION: Congenitally missing tooth is a risk factor for TMD. When treating the congenitally missing teeth population, TMJ evaluation and multidisciplinary strategies are necessary.

Computed tomography assessment of hypodontia and crown size in hemifacial microsomia.

OBJECTIVE: Our aims were to assess the prevalence of hypodontia in unilateral hemifacial microsomia (HFM), and to compare tooth (crown) size between affected and unaffected sides. DESIGN: In a retrospective cross-sectional study of South Australians, computed tomography (CT) scans were used to assess hypodontia and crown size (mesiodistal length, buccolingual width and crown height). The inclusion criteria were the absence of other congenital anomalies and the availability of CT scans. The exclusion criteria were the lack of extraction history or reproducible landmarks for morphometric assessment. The final sample comprised 41 participants in both dentitions, including 32 children and 9 adults (median age 13.9 years, range 0.4 - 47.6 years; 19 males and 22 females). Hypodontia was assessed in all participants, and the permanent crown size in 30 (73.2%) participants. Linear mixed-effects models were performed to determine if crown size was significantly different between the two sides, controlling for sex, HFM severity, and tooth and jaw type. RESULTS: Hypodontia occurred in none of the participants in the primary dentition, but in 6/30 (20%) participants in the permanent dentition (3/30 each on the affected and unaffected sides). There was no significant difference in the mean crown dimensions between the two sides, but the crown size was larger in males (p < 0.05), except for mesiodistal length, and became progressively smaller with increased HFM severity (p < 0.05). CONCLUSIONS: Hypodontia spared the primary dentition but featured prominently in the permanent dentition. The permanent crown dimensions were unaltered between the two sides.

Pre-implant and implant management of oligodontia patients: A 10-year retrospective study.

INTRODUCTION: the aim of this study was to report and assess the management and implant rehabilitation of oligodontia patients since its recognition in 2012 by french authorities in the nomenclature. MATERIAL AND METHODS: we conducted a retrospective study in the Maxillofacial Surgery and Stomatology Department of the Lille University Hospital between January 2012 and May 2022. Patients had to present an oligodontia recognized under the ALD31 in adulthood, and to have benefited from a pre-implant/implant surgical treatment in the unit. RESULTS: a total of 106 patients were included in the study. The mean number of agenesis was 12 per patient. The most missing teeth are the ones at the end of the series. After a pre-implant surgery phase including orthognathic surgery and/or bone grafting, 97 patients benefited from implant placements. The mean age for this phase was 19.38. A total of 688 implants were placed. The median number of implants placed was 6 per patient and 5 patients presented implant failures after or during the osseointegration phase (16 implants lost). The implant success rate was 97.6%. 78 patients benefited from rehabilitations by fixed implant-supported prostheses and 3 by implant-supported mandibular removable prostheses. DISCUSSION: The described care pathway seems to us adapted to the patients followed in our department, with good functional and esthetic results. It would be necessary to evaluate on a national scale to adapt the management process.

Patterns of nonsyndromic tooth agenesis and sexual dimorphism.

BACKGROUND: Sex dimorphism has been implicated in oral health differences and the pathogenesis of oral diseases, such as tooth agenesis, periodontal disease, dental caries, and tooth loss. Tooth agenesis (TA) is one of the most common developmental anomalies in humans, and its prevalence and patterns are different across ethnic groups. The aim of this study was to investigate the phenotypes and sex-associated patterns of nonsyndromic tooth agenesis (TA) in Thai dental patients. METHODS: One thousand ninety panoramic radiographs were examined. One hundred and one subjects (37 males, 64 females, 15-20 years-old) with nonsyndromic TA were evaluated. Differences in TA prevalence between groups were analyzed using the chi-square or Fisher exact test. RESULTS: The TA prevalence, excluding third molars, was 9.3% and more frequently found in the mandible compared with the maxilla. The maxilla demonstrated a higher prevalence of first premolar agenesis than the mandible (P = 0.012), while the mandible had a higher prevalence of second premolar agenesis than the maxilla (P = 0.031). There were significantly more males missing one tooth than females, however, there were more females missing two or more teeth than males (P = 0.042). A missing maxillary left lateral incisor was significantly more frequent in males (P = 0.019), while a missing mandibular right lateral incisor was more frequent in females (P = 0.025). In females, the pattern of two mandibular lateral incisors agenesis was the most common and significantly present in females more than males (P = 0.015). In contrast, the pattern of one mandibular left lateral incisor agenesis was only observed in males and significantly found in males more than females (P = 0.047). CONCLUSIONS: We demonstrate sex-associated differences in nonsyndromic tooth agenesis. The prevalence of single tooth agenesis was higher in males, while that of two or more teeth agenesis was higher in females. We found different patterns of lateral incisor agenesis between males and females.

Dental anomalies in an Albanian orthodontic sample: a retrospective study.

BACKGROUND: To evaluate the prevalence and the distribution of dental anomalies in an Albanian orthodontic sample. METHODS: For this retrospective study, a sample of panoramic radiographs (PR) of n. 779 (456 F and 323 M, mean age of 15.1 ± 5.5 years) Albanian subjects with no genetic syndromes or craniofacial malformations (e.g., cleft lip/palate), history of extraction, trauma or previous orthodontic treatment drawn from the archives of the University Dental Clinic Our Lady of Good Counsel, was examined. The inclusion criteria were: subjects from 8 to 30 years of age, good quality of PRs in order to allow the assessment of crown and root development. For different dental anomalies, both the prevalence and the association were evaluated by using Chi-square test (p < 0.05). RESULTS: 24.4% of the sample had at least one dental anomaly and 4.6% had more than one. The following dental anomalies were most prevalent: hypodontia (9.8%), dental impaction (7.6%), and ectopic eruption (5.3%). No statistically significant correlation was found between males and females (p > 0.05). CONCLUSIONS: The most common anomalies in this group are found to be those of number and position, and only radiological investigations can reveal either of these anomalies. Early diagnosis of dental anomalies can contribute to prevent their complications and to establish the most suitable therapy to achieve a functional occlusion.

Retrospective study of concomitant hypodontia and hyperdontia in 145 subjects.

OBJECTIVES: This study aims to investigate the incidence and clinical characteristics of concomitant hypodontia and hyperdontia (CHH) by performing panoramic radiographs. METHODS: A total of 41 648 panoramic radiographs of pediatric patients who were admitted to the hospitals from January 2019 to May 2021 were reviewed, and 145 CHH patients were included in the study. The presence of CHH was recorded. SPSS 24.0 software was used for statistical analysis. RESULTS: The prevalence of CHH was 0.35% (145/41 648). Males (102 cases) were obviously more than females (43 cases), and the difference between genders was statistically significant (P<0.001). The features of congenital permanent tooth loss in this group were predominantly 1 and 2 teeth missing and preferably mandibular lateral incisors and mandibular second premolars missing. The incidence of congenital permanent teeth loss was higher in the mandible than in the maxilla (P<0.001), but no difference was found in the distribution between left and right (P=0.84). The features of supernumerary teeth in this group were 1 and 2 teeth, mostly in the maxillary anterior area, mostly conical, mostly vertical inversion and orthotopic growth. CONCLUSIONS: CHH is a rare mixed numeric dental anomaly characterized by congenital missing teeth and supernumerary teeth occurring in the same individual. CHH cases are higher in men than in women. The characteristics of their hypodontia and hyperdontia are similar to those of patients with congenital permanent tooth absence or supernumerary teeth. Early diagnosis of the condition and a multidisciplinary approach for management of such case is recommended.

Non-syndromic hypodontia of maxillary lateral incisors and its association with other dental anomalies.

BACKGROUND: Tooth agenesis (TA) is the developmental absence of one or more teeth and is the most common craniofacial disorder in humans. Maxillary lateral incisor agenesis (MLIA) is a specific subtype of TA and can have esthetic, functional, and psychosocial implications for patients. The aim of this study was to evaluate the prevalence of MLIA amongst patients with non-syndromic tooth agenesis, as well as its association with other dental anomalies. MATERIALS AND METHODS: The dental records of 240 patients with non-syndromic congenitally missing teeth treated at the University of Alabama at Birmingham Department of Orthodontics were reviewed. Dolphin Imaging software was used to identify missing teeth, microdonts, peg laterals, impactions, and transpositions. Data were analyzed using chi-square or Fisher's exact test. All the tests were two-sided at the significance level of 0.05 (SAS 9.4). RESULTS: In the patient cohort, MLIA prevalence was 37.5% (second most common) and no gender or ethnic differences were identified. We also observed the bilaterally missing lateral incisors more frequently than the unilateral presentation (p = 0.0006). Additionally, 62.5% of patients with unilateral MLIA displayed a contralateral tooth that was a peg (p = 0.0001); however, no association was found with other microdonts. Furthermore, of the 90 patients missing at least one maxillary lateral incisor, 42.2% were missing another tooth type and 10% of MLIA patients also had an impacted tooth (mainly maxillary canines). However, these were not statistically significant. Finally, no transposed teeth were found in our patients. CONCLUSIONS: This study found that maxillary lateral incisors were the second most frequently missing teeth. When clinicians diagnose congenital absence of a maxillary lateral incisor, the patient should be evaluated for other missing teeth, peg lateral incisors, or potential impactions, especially maxillary canines.

Skeletal and dentoalveolar characteristics of maxillary lateral incisor agenesis patients: a comparative cross-sectional study.

BACKGROUND: The aim of the study was to evaluate the cephalometric and dentoalveolar characteristics of maxillary lateral incisor agenesis patients, and to compare the findings to a matched control group without tooth agenesis, excluding third molars, from the same population. METHODS: The pre-orthodontic records of 72 non-growing patients, who were treated at the Orthodontic Department, Faculty of Dentistry, Alexandria University, were used to address the aim of this retrospective study. Patients having unilateral or bilateral maxillary lateral incisor agenesis, with no history of previous orthodontic treatment, congenital craniofacial malformations, facial trauma, or surgeries were divided into two test groups based on the pattern of maxillary lateral incisors agenesis (group I: unilateral (UMLIA), group II: bilateral (BMLIA)). A control group (group III (CTRL)) having a complete set of permanent dentition (excluding third molars), and having no dental anomalies was age-matched with the test groups. Measurements were performed on the pre-orthodontic lateral cephalometric radiographs and the pre-orthodontic digital dental casts. The measured variables were compared between the groups using one-way ANOVA and Kruskal Wallis tests according to the normality of the variable. In case of significant results, both tests were followed by multiple pairwise comparisons using Bonferroni adjusted significance level. Significance level was set at P < 0.05. RESULTS: BMLIA group showed a smaller SNA angle and maxillary length, a more negative ANB angle and Wits appraisal, and a larger Maxillo-mandibular differential than UMLIA and/or CTRL group. The dental and soft tissue cephalometric measurements did not show any significant differences between the groups. Dentoalveolar cast measurements showed that BMLIA patients presented with significantly smaller maxillary inter-canine width than UMLIA and CTRL patients. CONCLUSIONS: Cephalometric analysis has shown that subjects with BMLIA have a statistically significant reduced ANB and maxillary length. Tooth eruption may play a role in the development of the maxillary arch.

Hallazgos en radiografías panorámicas de niños entre 6 y 15 años en un hospital odontológico en Argentina / Findings in panoramic radiographs of children between 6 and 15 years at a dental hospital in Argentina

Objetivo: Describir la frecuencia y localización de pato- logías y anomalías dentarias (anomalías de número, tumores, quistes y piezas retenidas) observadas en radiografías pa- norámicas de pacientes pediátricos de entre 6 y 15 años del Hospital Zonal Especializado en Odontología Infantil "Dr. A. Bollini" de la ciudad de La Plata. Materiales y métodos: Se realizó un estudio observa- cional descriptivo de 300 radiografías panorámicas, de niños (n=150) y niñas (n=150) de entre 6 y 15 años, seleccionadas aleatoriamente en el área de radiología del hospital, tomadas en el período comprendido entre marzo de 2018 y marzo de 2020. Los datos obtenidos se volcaron en planillas de cálculo y con ellos se realizó un análisis estadístico descriptivo. Se utilizaron las siguientes variables: edad, sexo, tipo de ano- malía o patología (anomalías de número, tumores, quistes y piezas retenidas), pieza dentaria y ubicación (maxilar o man- díbula). Resultados: Dentro de las anomalías registradas (n=147), se encontraron en mayor medida piezas dentarias retenidas, en un 44,22% de los casos (n=65), agenesias en un 42,18% de los casos (n=62) y supernumerarios en un 13,61% de los casos (n=20). No se hallaron quistes ni tumores. Conclusión: En un 24% de las radiografías panorámicas de niños entre 6 y 15 años se halló alguna anomalía dentaria. Las anomalías más frecuentes fueron piezas dentarias reteni- das y agenesias (AU)

Aim: To describe the frequency and location of dental pathologies and anomalies (number anomalies, tumors, cysts and retained dental pieces) observed in panoramic radio- graphs of pediatric patients between 6 and 15 years of age from the Hospital Especializado en Odontología Infantil "Dr. A. Bollini" from the city of La Plata. Materials and methods: A descriptive observational study was performed based on 300 panoramic radiographs of children (150 girls and 150 boys) between 6 and 15 years old, randomly selected in the Radiology area of the hospital, taken in the period between March 2018 and March 2020. The data obtained were entered into spreadsheets and a descriptive sta- tistical analysis was carried out. The following variables were evaluated: age, sex, type of anomaly or pathology (anomalies of number, tumor, cysts and retained dental pieces), dental piece and location (maxilla or mandible). Results: Among the registered anomalies (n=147), re- tained dental pieces were found to a greater extent, in 44.22% of the cases (n=65), agenesis in 42.18% of the cases (n=62) and supernumeraries in 13.61% of the cases (n=20). No cysts or tumors were found. Conclusion: In 24% of panoramic radiographs of chil- dren between 6 and 15 years old, some dental anomaly was found. The most frequent anomalies were retained dental pieces and agenesis (AU)

Association between dental agenesis and delay in dental development: a preliminary study in a Spanish paediatric population in relation with Dental Anomaly Pattern (DAP).

BACKGROUND: The association between dental anomalies has been studied, giving rise to the concept of Dental Anomaly Pattern (DAP). Tooth agenesis has been associated with alterations such as molar infracclusion, taurodontism and delayed dental development. The aim of this study was to evaluate the dental development pattern in patients with non-syndromic dental agenesis, in comparison with a control group. METHODS: Dental and chronological age was analysed in a sample size of 204 orthopantomographs divided into a study group (n = 104) and a control group (n = 100) with the Demirjian Method. Intra and intergroup differences in chronological and dental age, and the correlation between them were calculated by statistical analysis with a 95% confidence level (p < 0.05). RESULTS: Dental age exceeded chronological age both in the control group and in the study group. Statistically significant differences (p = 0.004) were found when comparing the difference between chronological and dental age in the study (-0.16 ± 1.12) and control group (-0.58 ± 0.90). Regarding sex and age intergroup differences, the results were only statistically significant in the girls' group (p = 0.017), and the age over 8 years old (p < 0.05). There were no significant differences in tooth development depending on the number of missing teeth or the affected tooth group, but there was a delay in the development of the homologous tooth contralateral to the absent one in 14.9% of patients. CONCLUSIONS: The difference between chronological and dental age in permanent dentition is significantly lower in Spanish children with non-syndromic agenesis compared to a control group, presenting a lower dental age than chronological age than children without non-syndromic agenesis.