Syndromes with supernumerary teeth

Comprehensive dental care in patient with Rubinstein-Taybi syndrome: A 3-year case study using progressive desensitization techniques and oral sedation

AIM

This case study delineates a minimally invasive and effective approach for the aesthetic and functional restoration of teeth in a patient with Rubinstein-Taybi syndrome (RTS), focusing on the challenges and strategies tailored to their specific dental care needs.

METHODS AND RESULTS

A 20-year-old patient diagnosed with RTS presented at the Pediatric Dentistry Department for a comprehensive dental assessment and care. The individual's genetic condition manifested in unique dental and craniofacial anomalies, complicating standard dental procedures. Following an initial consultation that underscored limited cooperation due to intellectual disabilities, a customized treatment plan was developed. This included behavior modification techniques to acclimate the patient to dental settings and procedures. Utilizing "simplified technologies" such as volumetric polymerization composites and self-etching primer and adhesive systems, tooth 36 was successfully treated. The approach showcased the potential for dental care in RTS patients with minimal sedation, prioritizing patient comfort and cooperation.

CONCLUSION

The successful dental treatment of the RTS patient highlights the importance of patient-centered, minimally invasive approaches in managing individuals with special healthcare needs. Emphasizing continuity of care and prioritizing restorative treatments facilitated significant improvements in oral health and patient cooperation. This case contributes to the sparse literature on dental care for RTS patients, advocating for specialized strategies to address their comprehensive oral health needs. The findings underscore the necessity for interdisciplinary collaboration and innovative care protocols to ensure effective and empathetic dental treatment for individuals with RTS.

Double Mesiodens in the Mixed Dentition of Non-syndromic North-Indian Patients: A Case Series

The presence of double mesiodens or mesiodentes, i.e., two supernumerary teeth in the maxillary midline, presents unique challenges in mixed dentition. Common clinical manifestations include delayed eruption, midline diastema, and occlusal disturbances, leading to complications such as root resorption, pathological migration of tooth, crowding, cyst formation, and malocclusion. Mesiodens can be associated with several syndromes, like cleidocranial dysplasia, familial adenomatous polyposis, trichorhinophalangeal syndrome, type I, Rubinstein-Taybi syndrome, and Nance-Horan syndrome, among others. It can also be secondary to trauma, hyperactivity of the dental lamina, and a combination of genetic and environmental factors, but its etiology continues to be idiopathic. Double mesiodens are relatively rare, so this clinical observation aimed to highlight five such cases of double mesiodens in mixed dentition in non-syndromic children and adolescents. Additionally, a literature search reporting cases of double mesiodens in the mixed dentition was done, and the results were tabulated. Clinicians should be able to identify indications of supernumerary teeth, specifically deviations in the eruption pattern. Appropriate investigations and timely intervention are essential to reducing complications that may arise in the developing dentition.

An Oral Odyssey: Navigating the Complexity of Impacted Parapremolars and Paramolars in the Oral Landscape!

Supernumerary molars are an uncommon anomaly that can occur in the maxillofacial complex, referring to the presence of additional teeth in the dental arch. This condition is often associated with several rare disorders such as Gardner's syndrome, Cleidocranial dysplasia, Ehler-Danlos syndrome, and Down syndrome However, it is seldom observed in non-syndromic associations. They occur more frequently in the maxilla than in the mandible. This research represents a unique case study that explores unerupted paramolar and parapremolar follicles coexisting in both the maxillary and mandibular arches of a 17-year-old male patient. The discovery of these follicles was fortuitous, as the patient exhibited no symptoms during the initial orthopantomogram scan. Despite the absence of noticeable symptoms, vigilant monitoring and observation were employed over time. Subsequently, a substantial shift in the approach to management occurred with the integration of surgical and orthodontic methodologies, guided eruption strategies, and a collaborative, multidisciplinary effort.

Clinical and imaging analysis of 22 cases of supernumerary teeth in the mandibular region

PURPOSE

This study aimed to describe clinical and imaging analysis of supernumerary teeth in the mandibular region of 22 cases.

STUDY DESIGN

Retrospective study METHODS: : This study enrolled patients diagnosed with supernumerary teeth who underwent cone beam computed tomography (CBCT) at Stomatology Hospital of Xi'an Jiaotong University from August 2016 to September 2022. Participants included individuals aged 7-29 years of both genders. The following variables were examined: number of supernumerary teeth, location, shape, direction, length, relationship with adjacent teeth and surrounding anatomical structures, and secondary effects RESULTS: : Out of 236 subjects, 22 (6.02%) were found to have supernumerary teeth in the mandibular region, with a total of 62 teeth identified. The male-to-female ratio was 5:6. Most supernumerary teeth were located in the lingual side of the mandibular region, particularly in the 34-35 tooth area (21.66%), followed by the 44-45 tooth region. The vast majority of supernumerary teeth (96.77%) were impacted, and more than half (51.67%) were located near the mental nerve canal. The average length of the supernumerary teeth was 10.5 mm. While no primary complications were observed, some secondary symptoms were noted, such as the ectopic eruption of adjacent teeth and crowding of permanent teeth.

CONCLUSION

The supernumerary teeth in the mandibular area have regional characteristics, which can provide for clinical diagnosis and treatment. CBCT can accurately analyze the location of supernumerary teeth and their secondary effects, and provides the treatment plan on that basis.

Tooth Migration in a Female Patient with Hyperdontia: 11-Year Follow-Up Case Report

We described an 11-year follow-up of a patient with a non-syndrome multiple supernumerary teeth who had one extra tooth in the maxilla and four additional premolars in the mandible. Together with an additional distal migration of the second lower right premolar to the ramus of the mandible that also occurred, it comprises a unique combination of conditions that were not previously presented in the literature. We showed the significance of routine X-rays in cases of hyperdontia since the additional teeth may develop later than expected and the patient may not experience any symptoms.

Heterozygous Variants in FREM2 Are Associated with Mesiodens, Supernumerary Teeth, Oral Exostoses, and Odontomas

BACKGROUND

Supernumerary teeth refer to extra teeth that exceed the usual number of dentitions. A mesiodens is a particular form of supernumerary tooth, which is located in the premaxilla region. The objective of the study was to investigate the genetic etiology of extra tooth phenotypes, including mesiodens and isolated supernumerary teeth.

METHODS

Oral and radiographic examinations and whole-exome sequencing were performed on every patient in our cohort of 122 patients, including 27 patients with isolated supernumerary teeth and 94 patients with mesiodens. A patient who had multiple supernumerary teeth also had odontomas.

RESULTS

We identified a novel (c.8498A>G; p.Asn2833Ser) and six recurrent (c.1603C>T; p.Arg535Cys, c.5852G>A; p.Arg1951His, c.6949A>T; p.Thr2317Ser; c.1549G>A; p.Val517Met, c.1921A>G; p.Thr641Ala, and c.850G>C; p.Val284Leu) heterozygous missense variants in FREM2 in eight patients with extra tooth phenotypes.

CONCLUSIONS

Biallelic variants in FREM2 are implicated in autosomal recessive Fraser syndrome with or without dental anomalies. Here, we report for the first time that heterozygous carriers of FREM2 variants have phenotypes including oral exostoses, mesiodens, and isolated supernumerary teeth.

Rare Genetic Variants in Human APC Are Implicated in Mesiodens and Isolated Supernumerary Teeth

The activation of Wnt/β-catenin signalling is a prerequisite for odontogenesis. APC, a member of the AXIN-CK1-GSK3β-APC β-catenin destruction complex, functions to modulate Wnt/β-catenin signalling to establish regular teeth number and positions. APC loss-of-function mutations are associated with the over-activation of WNT/β-catenin signalling and subsequent familial adenomatous polyposis (FAP; MIM 175100) with or without multiple supernumerary teeth. The ablation of Apc function in mice also results in the constitutive activation of β-catenin in embryonic mouse epithelium and causes supernumerary tooth formation. The objective of this study was to investigate if genetic variants in the APC gene were associated with supernumerary tooth phenotypes. We clinically, radiographically, and molecularly investigated 120 Thai patients with mesiodentes or isolated supernumerary teeth. Whole exome and Sanger sequencing identified three extremely rare heterozygous variants (c.3374T>C, p.Val1125Ala; c.6127A>G, p.Ile2043Val; and c.8383G>A, p.Ala2795Thr) in APC in four patients with mesiodentes or a supernumerary premolar. An additional patient with mesiodens was compound as heterozygous for two APC variants (c.2740T>G, p.Cys914Gly, and c.5722A>T, p.Asn1908Tyr). Rare variants in APC in our patients are likely to contribute to isolated supernumerary dental phenotypes including isolated mesiodens and an isolated supernumerary tooth.

Tooth number abnormality: from bench to bedside

Tooth number abnormality is one of the most common dental developmental diseases, which includes both tooth agenesis and supernumerary teeth. Tooth development is regulated by numerous developmental signals, such as the well-known Wnt, BMP, FGF, Shh and Eda pathways, which mediate the ongoing complex interactions between epithelium and mesenchyme. Abnormal expression of these crutial signalling during this process may eventually lead to the development of anomalies in tooth number; however, the underlying mechanisms remain elusive. In this review, we summarized the major process of tooth development, the latest progress of mechanism studies and newly reported clinical investigations of tooth number abnormality. In addition, potential treatment approaches for tooth number abnormality based on developmental biology are also discussed. This review not only provides a reference for the diagnosis and treatment of tooth number abnormality in clinical practice but also facilitates the translation of basic research to the clinical application.

Cranial trephination and infectious disease in the Eastern Mediterranean: The evidence from two elite brothers from Late Bronze Megiddo, Israel

Here we present the paleopathological profiles of two young adult males, identified as brothers through ancient DNA analysis, who were buried together beneath the floor of an elite early Late Bronze Age I (ca. 1550-1450 BC) domestic structure at the urban center of Megiddo (modern Israel). Both individuals displayed uncommon morphological variants related to developmental conditions, and each exhibited extensive bone remodeling consistent with chronic infectious disease. Additionally, one brother had a healed fracture of the nose, as well as a large square piece of bone cut from the frontal bone (cranial trephination). We consider the potential etiologies for the appearance of the skeletal anomalies and lesions. Based on the bioarchaeological context, we propose that a shared epigenetic landscape predisposed the brothers to acquiring an infectious disease and their elite status privileged them enough to endure it. We then contextualize these potential illnesses and disorders with the trephination procedure. The infrequency of trephination in the region indicates that only selected individuals could access such a procedure, and the severity of the pathological lesions suggests the procedure was possibly intended as curative to deteriorating health. Ultimately, both brothers were buried with the same rites as others in their community, thus demonstrating their continued integration in society even after death.

Molecular Genetics of Cleidocranial Dysplasia

Cleidocranial dysplasia (CCD) is a genetic disorder with an autosomal dominant inheritance pattern. CCD characterized by abnormal clavicles, patent sutures and fontenelles, supernumerary teeth and short stature. Approximately 60-70% of CCD patients have mutations in the RUNX2 gene. The RUNX2 gene is an essential transcription factor for chondrocyte maturation, osteoblast differentiation and bone formation. Runx2 regulates mesenchymal cell proliferation in sutures and suture closure by inducing the signaling pathways of the genes of Fgf, Pthlh, hedgehog and Wnt. Material and Methods: We summarized molecular genetics aspects of CCD. Result: Approximately 94% of CCD patients have dental anomalies, the most common of which are supernumerary tooth. Dental anomalies are not determined solely by gene mutations of RUNX2, but are also affected by modifier genes, environmental factors, epigenetic factors and copy number variations. Conclusion: a definite diagnosis of CCD should include the patient's clinical history, symptoms and signs, as well as genetic analyses.

Phenotypic dento-osseous characterization of a Brazilian family with Familial Adenomatous Polyposis

OBJECTIVE

To perform a phenotypic characterization of the dento-osseous anomalies in a Brazilian family with Familial Adenomatous Polyposis (FAP) and to investigate the adenomatous polyposis coli (APC) causative variant.

DESIGN

The study included a family of 14 individuals (Group A: affected; Group B: non-affected). The frequency of radiographic findings in both groups was evaluated according to the Dental Panoramic Radiograph Score (DPRS) diagnostic method. The accuracy and reproducibility of DPRS were tested. The DNA was isolated from the index patient's saliva and submitted to whole-exome and Sanger sequencing approach.

RESULTS

DPRS ≥ 7 was observed in 80 % of Group A but in none of Group B. The most common findings in Group A were dense bone islands (60 %), hazy sclerosis (40 %), osteomas (40 %), and supernumerary tooth (20 %). DPRS has proved to be a reliable method while DPRS ≥ 5 and DPRS ≥ 7 were taken as positive for FAP, and reproducible diagnosis test considering that the evaluators correctly identified the affected patients (Kappa agreement>0.8, p = 0.002). A nonsense heterozygous mutation in the APC gene (c.1370C > G; p.Ser457*) of the index case was detected.

CONCLUSION

FAP patients have a higher frequency of dento-osseous anomalies (p = 0.005). Bone abnormalities were more prevalent than dental anomalies (p = 0.001). Thus, FAP patients should be referred for dental examination and genetic counseling to perform early diagnosis of dento-osseous anomalies and evaluate the implications of the molecular findings in each particular family.

Oral and maxillofacial outcomes in children with microcephaly associated with the congenital Zika syndrome

INTRODUCTION

The objective of this study is to assess the oral and maxillofacial characteristics of microcephalic children associated with congenital Zika syndrome (CZS).

METHODS

A cross-sectional, observational study was carried out with 61 patients with microcephaly/CZS born between June 2015 and September 2017 (29 boys and 32 girls, average age of 22.8 months) and a control group with 58 non-CZS children born in the same period (25 boys and 33 girls, average age of 23.8 months). The functional clinical analysis considered the labial and lingual frena, tongue anterior projection, oral escape, palate form, and first tooth eruption. For the craniofacial analysis, facial anthropometric points and the cephalic perimeter at the time were measured. Demographic data were collected from medical records, and a clinical exam was performed in order to register the intrabuccal characteristics and craniofacial measures. The chi-square test and Student's t-test were used with a significance level of 0.05.

RESULTS

The narrow palate form, tongue anterior projection, oral escape, and late first tooth eruption were significantly more present in the group with microcephaly/CZS. As for the craniofacial analysis, face width (Bi-Zi), mandible width (Go-Go), height of face upper third (Tr-G), and monthly growth of cephalic perimeter were significantly smaller, whereas height of face lower third (Sn-Gn) was significantly bigger in the group with microcephaly/CZS (P < 0.05).

CONCLUSION

Children with microcephaly resulting from a congenital Zika infection showed functional, oral, and maxillofacial changes and smaller facial development in comparison with non-CZS children in the same age group.

Supernumerary Teeth and Dental Development

PURPOSE

The aims of this study were to compare the radiographic development of permanent teeth in a group of children with and without supernumerary teeth (ST), determine whether using cone-beam computed tomography or panoramic radiography improves the accuracy of dental age (DA) estimation and investigate the effects of factors including the numbers and positions of ST.

METHODS

One hundred fifty dental radiographs of children with and without ST at the ages of 6.0 to 14.9 years were included in this study. The children in both groups were age and sex-matched. The lower left-side 7 permanent teeth were evaluated according to the Demirjian method, DA was determined. The difference between chronological age (CA) and DA (CA-DA) for the children with and without ST and further based on the number and localization of ST were calculated.

RESULTS

For all groups, the mean DA values were higher than the mean CA values. The difference between the CA and DA values in the children with ST was higher than the difference in the children without ST. Supernumerary teeth in posterior localization, multiple ST and among boys were observed to increase the differences between the mean CA and DA values. The mean age difference between radiographies in the children with and without ST was similar.

CONCLUSION

Panoramic radiography was found adequate in determination of dental development with the Demirjian method. Dental development was even more advanced in the children with ST in comparison to the control group. Clinicians should keep in mind that the dental developments of children with supernumerary teeth may be advanced.

Epidemiological, clinical, radiographic characterization of non-syndromic supernumerary teeth in Chinese children and adolescents

OBJECTIVE

This retrospective study was purposed to evaluate epidemiological, clinical, and 3D radiological features of supernumerary teeth (ST) in a non-syndromic Chinese children and adolescent dental population.

MATERIALS AND METHODS

Original cone-beam CT (CBCT) data from 18,861 patients aged from 6 to 17 years with dental maxillofacial diseases treated in a Chinese dental hospital from June 2012 to December 2018 were utilized to screen patients with ST. Diagnosis and characterizations of ST were analyzed by CBCT coupled with 3D reconstruction. All relevant epidemiological, clinical, and radiographic details about ST were collected and statistically analyzed.

RESULTS

Among total 18,861 patients, 2,768 ST were identified in 1984 subjects with a prevalence of 10.52% and a male:female ratio of 1.86:1. Majority of ST were single, conical, inverted, impacted, and located in maxilla anterior region. ST-associated complications mainly included malposition, rotation, and impaction of adjacent teeth, which were notably associated with morphology and position of ST.

CONCLUSION

The prevalence of ST in Chinese children and adolescent dental population was 10.52% and tended to present as single, conical, inverted, and impacted, which resulted in abnormalities of neighboring teeth. Our outcomes are beneficial for clinicians to more comprehensively understand the incidence, characterization, and clinical treatment planning of ST in dental children and adolescents.

Teeth Impaction and Structural Teeth Anomalies

Dentists and oral and maxillofacial radiologists have used periapical, occlusal, panoramic, and cephalometric radiographs for many years for diagnosing dental anomalies, especially before orthodontic or surgical treatment. Cone beam computed tomography was developed in recent years especially for the dental and maxillofacial region. Thus it has become the imaging modality of choice for many clinical situations, such as the assessment of dental impaction and structural teeth anomalies or other associated diseases and disorders (e.g., Gardner's syndrome, cleidocranial dysplasia). This article reviews different aspects of dental impaction and its possible effects on adjacent structures such as external root resorption, marginal bone loss, as well as describing structural dental anomalies. It provides a systematic analysis of their characteristic features and imaging findings for general radiologists to achieve a precise diagnosis and an optimal interpretation.

The Broad Variability in Dental Age Observed among Childhood Survivors Is Cancer Specific

PURPOSE

The study aimed to assess the differences in dental maturation between childhood cancer survivors and healthy children.

Materials and Methods

Fifty-nine cancer patients including 16 (27.1%) girls and 43 (72.8%) boys, aged between 4 and 16 years, underwent dental and radiographic examinations. The mean duration of anticancer therapy was 16.8 months (range, 1 to 47 months), and 4.6 years (range, 8 to 123 months) had passed since the termination of disease. The control group consisted of 177 panoramic radiographs of age- and sex-matched healthy individuals. Dental age (DA) was estimated with Demirjian's scale and delta age, i.e., DA-chronological age (CA), was used to compare groups.

RESULTS

The DA of cancer survivors was accelerated by almost 1 year compared to their CA (9.9±3.1 vs. 8.9±2.8, p=0.040). The greatest difference was observed among patients with brain tumor: delta (DA-CA) was 2.2±1.1 years. Among all cancer patients, only children with familial adenomatous polyposis (FAP)-associated hepatoblastoma (HP) demonstrated delayed DA, with regard to both other cancer survivors (p=0.011) and healthy patients (p=0.037). All four patients with HP suffered from FAP, and three of them had documented adenomatous polyposis coli (APC) genes mutation. The DA of cancer patients having teeth with short roots was significantly greater than that of the cancer survivors without this anomaly (12.8±3.2 vs. 9.0±2.4, p < 0.001).

CONCLUSION

DA in children may be altered by cancer disease.

Three-dimensional evaluation of morphology and position of impacted supernumerary teeth in cases of cleidocranial dysplasia

Cleidocranial dysplasia (CCD) is a congenital anomaly characterized by the presence of impacted supernumerary teeth and delayed eruption of permanent teeth. However, there has been no detailed investigation on supernumerary teeth in patients with CCD using three-dimensional (3D) imaging techniques. The purpose of this study was to elucidate the morphology and position of supernumerary teeth using 3D images reconstructed from cone-beam computed tomography (CBCT) data in a group of five Japanese subjects (male, 3; female, 2; age, 15.0-25.4 years) with CCD. All five subjects exhibited supernumerary teeth (39 in total; average, 7.8; range, 1-15). All supernumerary teeth were impacted and existed as pairs with adjacent permanent teeth. Comparison of the size (the crown and dental-root lengths, the crown mesiodistal and buccolingual diameters), the number of cusps and dental roots, the position, and direction of supernumerary teeth in relation to the adjacent permanent teeth was analyzed. The results of relationship analyses revealed that, at sites other than the molar region, supernumerary teeth were positioned on the lingual and distal sides and supernumerary teeth resembled the morphology of their adjacent permanent teeth in terms of the number of cusps but were smaller than the adjacent permanent teeth. In the molar region, supernumerary teeth were microdontia, which were apparently small and obscure morphologically. In addition, while all adjacent permanent teeth exhibited normal direction, five supernumerary teeth exhibited inverse direction. The findings of this study will improve our understanding of the characteristics of CCD and provide important information for the pathophysiology and clinical treatment.

A Review of Benign Congenital Anomalies

Benign congenital anomalies are common in neonates. Some of these common benign congenital anomalies include preauricular pits, sacral dimples, supernumerary digits, accessory nipple, and natal teeth. It is important for health care providers who take care of newborns to recognize these benign anomalies so that unnecessary evaluations and investigations are not performed. However, some of these anomalies may be associated with clinically significant conditions. In this article, we discuss when further evaluation should be performed in babies presenting with these common benign congenital anomalies. [Pediatr Ann. 2020;49(2):e66-e70.].

Supernumerary teeth of permanent dentition in patients with neurofibromatosis type 1

PURPOSE

The purpose of the study was the investigation of supernumerary teeth (ST) in the permanent dentition of patients with neurofibromatosis type 1 (NF1).

MATERIAL AND METHODS

The panoramic radiographs of 200 NF1 patients were analysed for ST. The potential impact of certain neurogenic facial tumours on the measured variable was investigated separately. The results were compared to dental findings in panoramic radiographs of 200 age- and sex-matched controls.

RESULTS

The total number of ST in all individuals was 23 in 12 patients (3% of total population). However, all ST had developed in the group of NF1 patients (6%), (p = 0.0004). ST were particularly common distal to the molar region. Although ST occur in the region of facial plexiform neurofibroma, the numerical aberrations of the dentition are independent of specific type of facial nerve sheath tumour.

CONCLUSION

The unusual accumulation of ST in the terminal sections of molar development could be an indicator of preferred points of developmental disorder, in which the genetic predisposition of the patient is involved. Reviewing the results of other NF1 patient collectives is desirable.

Third Dentition Is the Main Cause of Premolar Supernumerary Tooth Formation

While the prevalence of supernumerary teeth (ST) is high in permanent dentition, the etiology of ST in humans remains unclear. However, multiple murine models of ST have elaborated on dated mechanisms traditionally ascribed to ST etiology: one involves the rescue of rudimental teeth, and the second considers the contribution of odontogenic epithelial stem cells. It remains unclear whether these mechanisms of ST formation in mice are applicable to humans. The third dentition is usually regressed apoptotic-that is, the teeth do not completely form in humans. Recently, it was suggested that ST result from the rescue of regression of the third dentition in humans. The present investigation evaluates the proportion of collected general ST cases that evinced a third dentition based on the clinical definition of ST derived from the third dentition. We also investigated the contribution of SOX2-positive odontogenic epithelial stem cells to ST formation in humans. We collected 215 general ST cases from 15,008 patients. We confirmed that the general characteristics of the collected ST cases were similar to the results from previous reports. Of the 215 cases, we narrowed our analysis to the 78 patients who had received a computed tomography scan. The frequency of ST considered to have been derived from the third dentition was 26 out of 78 cases. Evidence of a third dentition was especially apparent in the premolar region, was more common in men, and was more likely among patients with ≥3 ST. SOX2-positive odontogenic epithelial stem cells within the surrounding epithelial cells of developing ST were observed in non-third dentition cases and not in third dentition cases. In conclusion, the third dentition is the main cause of ST in humans. The odontogenic epithelial stem cells may contribute to ST formation in cases not caused by a third dentition.

Two Rare Cases of Non-Syndromic Paramolars with Family Occurrence and a Review of Literature

Supernumerary teeth (or hyperdontia) are teeth that exceed the normal number of deciduous or permanent teeth in the oral cavity. The occurrence of supernumerary teeth without any associated syndrome has been frequently reported and many case reports have been published. This article reports two rare cases of familial occurrence of multiple paramolars without the presence of any other syndrome for two consecutive generations. Limited cases of bilateral maxillary or mandibular paramolars have been reported. In addition, prevalence, classification, etiology, complications, diagnosis and therapeutic strategies that may be adopted when supernumeraries occur are discussed. A review of similar cases published in the literature is included as well.

Dental Abnormalities and Oral Pathology of the Pataud 1 Upper Paleolithic Human

We have re-evaluated the dental abnormalities and oral pathology evident on the Mid-Upper Paleolithic Pataud 1 skeleton, including additional remains recently excavated for this individual, in an effort to expand current knowledge of Pleistocene human paleopathology, in light of current clinical and paleopathological assessments of oral variation and diseases. The young adult female Pataud 1 presents an impacted right M3, widespread periodontitis, large retromolar voids, double right maxillary supernumerary (paramolar) teeth, and new bone deposition on the medial mandibular rami and posterior maxillae. The Pataud 1 remains thus join a substantial sample of Pleistocene humans with congenital/developmental abnormalities, some of which (as in Pataud 1) consequently resulted in secondary abnormalities. M3impaction and supernumerary teeth are known in a couple of other Mid-Upper Paleolithic individuals, and mild to moderate periodontal disease appears to have been widespread. However, such marked resorption of the alveolar margin in a young adult is unusual, and the secondary inflammation (possibly septicemia) leading to new bone deposition is otherwise unknown in the sample and may have led to her death.

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.

Multiple supernumerary teeth in a likely syndromic individual from prehistoric Illinois

OBJECTIVE

This paper reports the first published case of a prehistoric human with five or more supernumerary teeth. Such cases are often neglected in paleopathology, in part due to a gap between the medicodental and anthropological literature leading to the view in anthropology that supernumerary teeth are curious anomalies rather than pathologies.

DESIGN

Reconstruction and pathological description of the skeletal remains were performed according to standard osteological protocols. Each supernumerary tooth was categorized based on its morphology, location, and orientation. The dental characteristics of the individual were compared to published norms for incidences of syndromic and non-syndromic supernumerary teeth and a differential diagnosis was subsequently performed.

RESULTS

Six supernumerary teeth and one deciduous tooth were identified. Additionally, the individual suffered from impacted teeth, dilacerated roots, and extensive sutural anomalies (including retention of the metopic suture into adulthood and an unusually high number of sutural bones). The morphology and location of the supernumerary teeth, in conjunction with the suite of other symptoms, are highly unusual among non-syndromic patients and therefore are indicative of a complex genetic disorder.

CONCLUSIONS

The individual reported here almost certainly suffered from a genetic disorder or syndrome resulting in extensive dental and sutural abnormalities. Despite a lack of post-cranial involvement, a tentative diagnosis of Cleidocranial Dysplasia was made on the basis that mutations in the RUNX2 gene may cause the dental symptoms without any pathology of the clavicle.

Supernumerary Molars and Wisdom Tooth Shape Alterations in Patients with Neurofibromatosis Type 1

Objectives

The purpose of the present study was the systematic investigation of numerical and morphological aberrations of teeth in the wisdom teeth region in neurofibromatosis type 1 patients.

Material and Methods

The panoramic radiographs of 179 patients were analysed for supernumerary molars and dysplastic wisdom teeth with special reference to facial tumour type. The results were compared to radiographic findings obtained in panoramic radiographs of age- and sex-matched controls.

Results

The total number of dysplastic or supernumerary molars was 21 (17 individuals, 4.75%) and predominantly a finding of the maxilla (maxilla: 15, mandible: 1, maxilla and mandible: 1). Differences of dental findings between neurofibromatosis type 1 (NF1) patients (n = 15) and the control group (n = 2) were statistically significant (P < 0.01). All individuals with supernumerary molars were diagnosed as being affected with NF1. This difference achieved statistical significance when it was considered that the event may occur at least once per quadrant, and thus the individual potentially needs to be considered four times (P = 0.0038).

Conclusions

This investigation revealed that supernumerary molars and aberrations in wisdom tooth form are more common in patients than in age- and sex-matched controls. There is no association between these findings and a specific feature of the disease, id est facial manifestation of a trigeminal nerve sheath tumour (plexiform neurofibroma). The cause of this phenomenon is unknown. A review of these dental findings on other neurofibromatosis type 1 study groups should be attempted.

Alterations in Tooth Structure and Associated Systemic Conditions

A variety of factors can affect the normal development of tissues and may lead to variation in the normal compliment of teeth and development of alterations in the shape and size of teeth. These anomalies can be congenital, developmental, or acquired. Dental anomalies can present as isolated traits or be associated with systemic conditions and syndromes for which early diagnosis and genetic testing may result in better treatment outcomes and quality of life. Dentists play an essential role in the multidisciplinary management of these abnormalities. This article discusses some of these tooth alterations and associated systemic and genetic conditions.

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.

Genetic Disorders of Dental Development: Tales from the Bony Crypt

PURPOSE OF REVIEW

The ebb and flow of genetic influence relative to the understanding of craniofacial and dental disorders has evolved into a tacit acceptance of the current genetic paradigm. This review explores the science behind craniofacial and dental disorders through the lens of recent past and current findings and using tooth agenesis as a model of advances in craniofacial genetics.

RECENT FINDINGS

Contemporary studies of craniofacial biology takes advantage of the technological resources stemming from the genomic and post-genomic eras. Emerging data highlights the role of key genes and the epigenetic landscape controlling these genes, in causing dentofacial abnormalities. We also report here a novel Glu78FS MSX1 mutation in one family segregating an autosomal dominant form of severe tooth agenesis as an illustration of an evolving theme, i.e., different mutations in the same gene can result in a spectrum of dentofacial phenotypic severity. The future of clinical therapeutics will benefit from advances in genetics and molecular biology that refine the genotype-phenotype correlation. Indeed, the past century suggests a continued convergence of genetic science in the practice of clinical dentistry.