Oral and maxillofacial manifestations of familial adenomatous polyposis

Case report: Initial atypical skeletal symptoms and dental anomalies as first signs of Gardner syndrome: the importance of genetic analysis in the early diagnosis

Background: Gardner syndrome is a rare genetic cancer predisposition disorder characterized by intestinal polyposis, multiple osteomas, and soft and hard tissue tumors. Dental anomalies are present in approximately 30%-70% of patients with Gardner syndrome and can be discovered during routine dental examinations. However, sometimes the diagnosis is challenging due to the high clinical variability and incomplete clinical picture. Herein, we report a family with various dental and bone anomalies, in which the definitive diagnosis was established with the help of a comprehensive genetic analysis based on state-of-the-art next-generation sequencing technology. Case presentation: A 17-year-old female index patient presented with dental (caries, impacted, retained and anteriorly located teeth) and atypical bone anomalies not resembling Gardner syndrome. She was first referred to our Genetic Counselling Unit at the age of 11 due to an atypical bone abnormality identified by a panoramic X-ray. Tooth 3.6 was surgically removed and the histopathology report revealed a Paget's disease-like bone metabolic disorder with mixed osteoblastic and osteoclastic activity of the mandible. A small lumbar subcutaneous tumor was discovered by physical examination. Ultrasound examination of the tumor raised the possibility of a soft tissue propagation of chondromatosis. Her sister, 2 years younger at the age of 14, had some benign tumors (multiple exostoses, odontomas, epidermoid cysts) and impacted teeth. Their mother had also skeletal symptoms. Her lower teeth did not develop, the 9th-10th ribs were fused, and she complained of intermittent jaw pain. A cranial CT scan showed fibrous dysplasia on the cranial bones. Whole exome sequencing identified a heterozygous pathogenic nonsense mutation (c.4700C>G; p.Ser1567*) in the APC gene in the index patient's DNA. Targeted sequencing revealed the same variant in the DNA of the other affected family members (the sister and the mother). Conclusion: Early diagnosis of this rare, genetically determined syndrome is very important, because of the potentially high malignant transformation of intestinal polyps. Dentists should be familiar with the typical maxillofacial features of this disorder, to be able to refer patients to genetic counseling. Dental anomalies often precede the intestinal polyposis and facilitate the early diagnosis, thereby increasing the patients' chances of survival. Genetic analysis may be necessary in patients with atypical phenotypic signs.

Radiographic Orofacial Findings of Systemic Diseases

This article discusses the orofacial clinicoradiographic features of systemic diseases that manifest in the orofacial region. The systemic diseases discussed are grouped into the following: autoimmune diseases, endocrine diseases, bone diseases, hematologic diseases, syndromes, and malignancies. The radiographic manifestation ranges from radiolucent bony destruction, increased bone density, calcification, thinning of cortical plate, loss of trabeculation, missing teeth, and supernumerary teeth. It is imperative for clinicians to be cognizant of these findings, as they may be the first manifestation of these systemic diseases.

A role for total alloplastic temporomandibular joint replacement in Gardner syndrome

Gardner syndrome (GS) is a rare autosomal dominant disorder that can present with craniomaxillofacial abnormalities. The identification of osteomas or craniomaxillofacial abnormalities can therefore serve as a marker of this condition, facilitating early referral and diagnosis. A 17-year-old female with GS was referred for the management of severe limited mouth opening, causing a major problem for routine endoscopy to monitor the gastrointestinal alterations of GS. Clinical and radiological evaluations showed multiple osteomas in the mandibular angle, condylar and coronoid regions bilaterally and maximum mouth opening of 8 mm. The patient underwent surgery for osteoma removal and bilateral customized alloplastic total temporomandibular joint replacement (TMJ-TJR). At the 2-year follow-up, the patient showed improvements in quality of life, with a maximum mouth opening of 34 mm, allowing routine upper endoscopy to be performed. This is the first report of GS, a rare and challenging craniomaxillofacial abnormality, treated with TMJ-TJR. A comprehensive overview of the patient's clinical presentation, diagnostic assessment, treatment planning, and outcomes is provided.

Identification of odontogenic ameloblast associated as a novel target gene of the Wnt/β-catenin signaling pathway

The Wnt/β-catenin signaling pathway plays a key role in development and carcinogenesis. Although some target genes of this signaling have been identified in various tissues and neoplasms, the comprehensive understanding of the target genes and their roles in the development of human cancer, including hepatoma and colorectal cancer remain to be fully elucidated. In this study, we searched for genes regulated by the Wnt signaling in liver cancer using HuH-7 hepatoma cells. A comparison of the expression profiles between cells expressing an active form of mutant β-catenin and cells expressing enhanced green fluorescent protein (EGFP) identified seven genes upregulated by the mutant β-catenin gene (CTNNB1). Among the seven genes, we focused in this study on ODAM, odontogenic, ameloblast associated, as a novel target gene. Interestingly, its expression was frequently upregulated in hepatocellular carcinoma, colorectal adenocarcinoma, and hepatoblastoma. We additionally identified a distant enhancer region that was associated with the β-catenin/TCF7L2 complex. Further analyses revealed that ODAM plays an important role in the regulation of the cell cycle, DNA synthesis, and cell proliferation. These data may be useful for clarification of the main molecular mechanism(s) underlying these cancers.

Osteoma of the Jaw as First Clinical Sign of Gardner's Syndrome: The Experience of Two Italian Centers and Review

Gardner's syndrome (GS) is a combination of polyposis, osteomas, fibromas, and sebaceous cysts. The aim of the study is to highlight whether maxillofacial osteoma could represent an early detection symptom of GS. Patients with suspected osteoma of the jaw underwent genetic and radiographical examinations. The database gathered 19 patients with oral osteoma that was histologically diagnosed; the whole sample was positive for APC gene mutation. Other cranial and peripheral locations were reported. Osteoma of the jaw is a crucial predictive factor of GS, and dentists and oral and maxillofacial surgeons must be aware of the importance of a timely diagnosis.

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.

Clinical manifestations of gastrointestinal diseases in the oral cavity

Aim

In this review, several gastrointestinal diseases that dentists may encounter in practice are highlighted and discussed.

Materials and methods

Using MEDLINE (PubMed), a comprehensive review of gastrointestinal diseases and their oral cavity manifestations was performed.

Results

Many gastrointestinal diseases present with oral symptoms that are detectable by dentists and dental hygienists. Often, oral manifestations of the disease may appear before systemic signs and symptoms. Managing patients with these conditions requires dentists to adjust their treatment and/or involve other health professionals.

Conclusion

Care must be taken when providing periodontal therapy or dental implants to patients suffering gastrointestinal diseases who are at high risk of bleeding, infection, or malnutrition, for example. Also, pharmacological therapy for these patients may need to be customized.

Possible Association Between Nickel and Multiple Osteomas of the Mandible in a Gir Bullock

A 10-year-old Gir bullock was presented with four contiguous hard nodular submucosal masses attached to the right rostral mandible. Overgrown masses were resected surgically and submitted for microstructural, elemental, and molecular spectroscopic analyses. An osteoma was diagnosed histopathologically. Elemental analysis by energy dispersive X-ray fluorescence spectroscopy revealed the presence of Ca, P, Sr, S, Zn, Cu, Ni, and Fe. Levels of the trace elements Fe, Zn, and Cu in the mandible mass were 2.39, 1.86, and 1.25 times higher, respectively, than those of normal bone. Nickel was detected in the mandible mass, but not in the normal bone. Molecular Fourier transform infrared spectroscopy confirmed the presence of inorganic ν₂ CO₃^2-, ν₃ PO₄^3-, and OH^- in addition to organic collagen amide B, amide I, amide II, and amide III chemical functional groups. Multiple osteomas of the mandible in humans are a feature of Gardner syndrome and have not been recognized in animals so far. This could be the first report of multiple osteomas of the mandible in a Gir bullock associated with nickel-induced epigenetic mutation.

A comparison of panoramic radiographic findings in patients with familial adenomatous polyposis and the general population: a multicenter study

OBJECTIVES

Familial adenomatous polyposis (FAP) is a hereditable disorder characterized by early and unremitting development of intestinal polyps and extraintestinal manifestations requiring multidisciplinary surveillance. Herein we describe a multicenter cross-sectional analysis of the dento-osseous radiographic findings of patients with FAP from North and South America.

STUDY DESIGN

Groups I and II included individuals with FAP diagnosed by standard clinical criteria. Patients were paired with age- and sex-matched participants without FAP. Panoramic radiograph of both cohorts, including children and adults, were analyzed.

RESULTS

Of 114 panoramic radiographs, 38 were from patients with FAP, composed of group I (n = 22) and group II (n = 16), and 76 were from matched control participants. Evaluators had excellent agreement on key findings (intraclass correlation coefficient = 0.89). The prevalence of osseous anomalies was higher in adults (75%) than in children (65.4%). Dental anomalies were also higher in children with FAP with a prevalence of 15.4%.

CONCLUSIONS

We describe important and significant differences in the prevalence of dento-osseous anomalies in children compared with adult patients with FAP. These findings warrant careful consideration and may influence multidisciplinary management of the condition. Conversely, the presence of these abnormalities in pediatric dental patients even if not diagnosed with FAP should be borne in mind as possibly indicating de novo or unrecognized disease.

Novel Mutation in APC Gene Associated with Multiple Osteomas in a Family and Review of Genotype-Phenotype Correlations of Extracolonic Manifestations in Gardner Syndrome

Gardner syndrome is a neoplasic disease that associates intestinal polyposis and colorectal adenocarcinoma with osteomas and soft tissue tumors determined by germline mutations in the APC gene. The early diagnosis and identification of high-risk individuals are important because patients have a 100% risk of colon cancer. We present the case of a family with Gardner syndrome. Cephalometric, panoramic X-rays and CBCT of the proband and her brother showed multiple osteomas affecting the skull bones, mandible and paranasal sinuses. The detailed family history showed an autosomal dominant transmission with the presence of the disease in the mother and maternal grandfather of the proband. Both had the typical signs of disease and died in the fourth decade of life. Based on these aspects the clinical diagnosis was Gardner syndrome. By gene sequencing, a novel pathogenic variant c.4609dup (p.Thr1537Asnfs*7) in heterozygous status was identified in the APC gene in both siblings. We reviewed literature data concerning the correlation between the localization of mutations in the APC gene and the extracolonic manifestations of familial adenomatous polyposis as well as their importance in early diagnosis and adequate oncological survey of patients and families based on abnormal genomic variants.

Genetic Determinants of Inherited Endocrine Tumors: Do They Have a Direct Role in Bone Metabolism Regulation and Osteoporosis?

Endocrine tumors are neoplasms originating from specialized hormone-secreting cells. They can develop as sporadic tumors, caused by somatic mutations, or in the context of familial Mendelian inherited diseases. Congenital forms, manifesting as syndromic or non-syndromic diseases, are caused by germinal heterozygote autosomal dominant mutations in oncogenes or tumor suppressor genes. The genetic defect leads to a loss of cell growth control in target endocrine tissues and to tumor development. In addition to the classical cancer manifestations, some affected patients can manifest alterations of bone and mineral metabolism, presenting both as pathognomonic and/or non-specific skeletal clinical features, which can be either secondary complications of endocrine functioning primary tumors and/or a direct consequence of the gene mutation. Here, we specifically review the current knowledge on possible direct roles of the genes that cause inherited endocrine tumors in the regulation of bone modeling and remodeling by exploring functional in vitro and in vivo studies highlighting how some of these genes participate in the regulation of molecular pathways involved in bone and mineral metabolism homeostasis, and by describing the potential direct effects of gene mutations on the development of skeletal and mineral metabolism clinical features in patients.

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.

Benign connective and soft-tissue neoplasms of the oral and maxillofacial region: Cross-sectional study of 1066 histopathological specimens

BACKGROUND

Benign connective and soft-tissue neoplasms (CSTNs) are unusual in the head and neck region. The aim of the present study was to evaluate the demographic and clinicopathological features of these neoplasms.

METHODS

A cross-sectional study was conducted of cases diagnosed as benign CSTNs, with data collected from biopsy records. The chi-square test was used. A p-value <0.05 was considered indicative of statistical significance.

RESULTS

Among the 38 119 specimens, 1066 (2.79%) were benign CSTNs: 369 fibroblastic/myofibroblastic, 250 adipocytic, 179 vascular, 130 neural, 94 osseous/cartilaginous, 19 muscular, and two fibrohistiocytic. Most patients were female (62.8%) and white-skinned (45.8%). Mean age was 42 years. The tongue (25.2%) was the most affected site for extraosseous neoplasms.

CONCLUSION

This study had the largest sample of benign oral and maxillofacial CSTNs. Although these tumors have similar clinical features, the characterization and differentiation detailed here may help clinicians with regards to the correct diagnosis.

Jaw and Dental Abnormalities

Deviations from anthropometric norms related to facial skeletal development are a relatively normal occurrence in the dental management of the vast majority of patients. A consideration for correction is usually warranted only when there is associated morbidity, functional impairment, or psychosocial detriment. The vast majority of jaw and dental abnormalities are developmental and present themselves within a continuum of clinically conspicuous to overtly obvious. This article highlights a variety of developmental abnormalities that present with structural disharmony of the maxillomandibular complex and secondarily associated dental structures.

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.

Genetic and developmental disorders of the oral mucosa: Epidemiology; molecular mechanisms; diagnostic criteria; management

A large number of disorders may affect the oral cavity, including genetic diseases, infections, cancers, blood diseases, skin diseases, endocrine and metabolic disorders, autoimmune and rheumatologic diseases, local lesions, to name a few. Oral mucosa shows a considerable variation in its normal structure and a wide range of conditions may affect it. Such conditions are often harmless or minor and could be primary or secondary to systemic disease. Several of them are quite rare and, hence, the diagnosis is not easy. Clinically, lesions may appear as ulcers, discoloration of the oral mucosa and alterations in size and configuration of oral anatomy. Genetic disorders have specific manifestations and can be caused by a derangement of one or more components of the tissue. Many of them follow the skin or systemic signs of the underlying genetic disease, but in a few cases oral signs could be the first manifestation of the disorder. Among them genodermatoses are prominent. They are inherited disorders characterized by a multisystem involvement. This review describes chondro-ectodermal dysplasia, dyskeratosis congenita, Ehlers-Danlos syndrome, hereditary benign intraepithelial dyskeratosis, keratosis follicularis, lipoid proteinosis, multiple hamartoma syndrome, pachyonychia congenita, Peutz-Jeghers syndrome, tuberous sclerosis and white sponge nevus. Other genetic disorders not included in the genodermatosis group and reported in the present review are: acanthosis nigricans, angio-osteo-hypertrophic syndrome, encephalotrigeminal angiomatosis, familial adenomatous polyposis, focal dermal hypoplasia, focal palmoplantar and oral mucosa hyperkeratosis syndrome, gingival fibromatosis, Maffucci's syndrome, neurofibromatosis (type 1) and oro-facial-digital syndrome (type 1). Disorders during embryonic development might lead to a wide range of abnormalities in the oral cavity; some of them are quite common but of negligible concern, whereas others are rare but serious, affecting not only the oral mucosa, but also other structures of the oral cavity (ie palate, tongue and gingiva). Fordyce's granules, leukoedema, cysts of the oral mucosa in newborns, retrocuspid papilla, geographic tongue, fissured tongue, median rhomboid glossitis, hairy tongue, lingual varices and lingual thyroid nodule are described. This review may help dentists, dental hygienists, but also general internists and pediatricians to diagnose different disorders of the oral mucosa, to understand the pathogenesis and to schedule a treatment plan.

Hereditary Cancer Syndromes-A Primer on Diagnosis and Management, Part 2: Gastrointestinal Cancer Syndromes

Hereditary causes due to mutations and defects in certain genes account for roughly 5% to 10% of all colorectal cancers. These inherited syndromes have been associated with a 60% to 100% lifetime risk for development of colorectal cancer, depending on the genetic syndrome, and many also carry an increased risk for multiple extracolonic malignancies. In this second part of a review series on hereditary cancer syndromes, the focus will be to provide guidance on the features and management of the most commonly encountered hereditary colorectal cancers and polyposis conditions including Lynch syndrome, familial adenomatous polyposis, MUTYH-associated polyposis, and hamartomatous polyposis.

A Case Report on Gardner Syndrome With Dental Implant Treatment and a Long-Term Follow-Up

A case of Gardner syndrome (GS) in a 37-year-old woman is presented in which rehabilitation with dental implant treatment was followed for 7 years. The course of diagnostics and treatment is followed through an overview of 45 tissue biopsy and cytology samples during a period of 30 years. The patient was diagnosed with GS after a routine review of an oral panoramic radiograph presenting with multiple osteomas and multiple unerupted supernumerary teeth. Biopsy results and surgical procedures with histopathologic diagnoses from 1986 to 2016 are presented. Histologic analysis of the sampled jawbone showed a picture similar to an osteoid osteoma. The installed implant was functionally stable, with no clinical or radiographic events observed at yearly visits, for 7 years. In 1991, benign tumors appeared; in 2014, multiple adenomas were found in the small intestine and rectum. This case report shows the potential for dental implant treatment in a patient with GS.

Wnt/β-catenin signaling, which is activated in odontomas, reduces Sema3A expression to regulate odontogenic epithelial cell proliferation and tooth germ development

Odontomas, developmental anomalies of tooth germ, frequently occur in familial adenomatous polyposis patients with activated Wnt/β-catenin signaling. However, roles of Wnt/β-catenin signaling in odontomas or odontogenic cells are unclear. Herein, we investigated β-catenin expression in odontomas and functions of Wnt/β-catenin signaling in tooth germ development. β-catenin frequently accumulated in nucleus and/or cellular cytoplasm of odontogenic epithelial cells in human odontoma specimens, immunohistochemically. Wnt/β-catenin signaling inhibited odontogenic epithelial cell proliferation in both cell line and tooth germ development, while inducing immature epithelial bud formation. We identified Semaphorin 3A (Sema3A) as a downstream molecule of Wnt/β-catenin signaling and showed that Wnt/β-catenin signaling-dependent reduction of Sema3A expression resulted in suppressed odontogenic epithelial cell proliferation. Sema3A expression is required in appropriate epithelial budding morphogenesis. These results suggest that Wnt/β-catenin signaling negatively regulates odontogenic epithelial cell proliferation and tooth germ development through decreased-Sema3A expression, and aberrant activation of Wnt/β-catenin signaling may associate with odontoma formation.

The Surgical Management of Gardner Syndrome Manifestation in the Maxillofacial Region: A Case Report

Gardner syndrome is a rare autosomal-dominant genetic disorder, considered a variant of familial adenomatous polyposis. It is characterized by intestinal polyposis and various bone and soft-tissue tumors, including osteomas, epidermal and dermal cysts, lipomas and fibromas. Intestinal polyps have high potential to become malignant, and the screening of intestinal lesions is mandatory. Maxillofacial manifestations, such as jaw osteomas, odontomas, dental abnormalities and soft tissue tumors frequently precede the intestinal manifestations. Thus, maxillofacial surgeons and dental practitioners may have important role in early detection of Gardner syndrome. In this case report we present a 22 year old male patient who was reffered to maxillofacial surgeon due to osteoma of the mandible. After obtaining clinical and radiological examinations, as well as data from family history, Gardner syndrome was suspected, which was later confirmed after gastroenterological examination.

Bone and dental abnormalities as first signs of familial Gardner's syndrome in a Chinese family: a literature review and a case report

Gardner's syndrome (GS) is an autosomal dominant disease characterized by the presence of familial adenomatous polyposis (FAP) as well as extraintestinal manifestations such as osteomas, dental anomalies, epidermoid cysts and ocular abnormalities. These intestinal polyps carry a 100% risk of malignant change, so early diagnosis is crucial. As craniofacial osteomas and dental anomalies of GS usually precede gastrointestinal symptoms, otolaryngologists, oral surgeons and dentists play an important role in the diagnosis of GS. GS is extensively reported in literature in the Caucasian race but not in the Mongoloid race. We report a case of a 22-year-old patient with a manifestation of three features of GS - multiple osteomas, soft tissue tumors and dental anomalies in the craniofacial region, with no intestinal polyps at the time of reporting. A family pedigree with our patient as the proband was constructed and revealed 3 consecutive generations in his lineage with GS.

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.

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.

Hereditary Colorectal Polyposis and Cancer Syndromes: A Primer on Diagnosis and Management

Colorectal cancer (CRC) is the fourth most common cancer amongst men and women. Between 3 and 6% of all CRCs are attributed to well-defined inherited syndromes, including Lynch syndrome, familial adenomatous polyposis (FAP), MUTYH-associated polyposis (MAP), and several hamartomatous polyposis conditions. Identification of these patients through family history and appropriate genetic testing can provide estimates of cancer risk that inform appropriate cancer screening, surveillance and/or preventative interventions. This narrative review examines the hereditary colorectal cancer and polyposis syndromes, their genetic basis, clinical management, and evidence supporting cancer screening.

Genetic alterations in mesiodens as revealed by targeted next-generation sequencing and gene co-occurrence network analysis

OBJECTIVE

Mesiodens is the most common type of supernumerary tooth which includes a population prevalence of 0.15%-1.9%. Alongside evidence that the condition is heritable, mutations in single genes have been reported in few human supernumerary tooth cases. Gene sequencing methods in tradition way are time-consuming and labor-intensive, whereas next-generation sequencing and bioinformatics are cost-effective for large samples and target sizes.

MATERIALS AND METHODS

We describe the application of a targeted next-generation sequencing (NGS) and bioinformatics approach to samples from 17 mesiodens patients. Subjects were diagnosed on the basis of panoramic radiograph. A total of 101 candidate genes which were captured custom genes were sequenced on the Illumina HiSeq 2500. Multistep bioinformatics processing was performed including variant identification, base calling, and in silico analysis of putative disease-causing variants.

RESULTS

Targeted capture identified 88 non-synonymous, rare, exonic variants involving 42 of the 101 candidate genes. Moreover, we investigated gene co-occurrence relationships between the genomic alterations and identified 88 significant relationships among 18 most recurrent driver alterations.

CONCLUSION

Our search for co-occurring genetic alterations revealed that such alterations interact cooperatively to drive mesiodens. We discovered a gene co-occurrence network in mesiodens patients with functionally enriched gene groups in the sonic hedgehog (SHH), bone morphogenetic proteins (BMP), and wingless integrated (WNT) signaling pathways.

Making extra teeth: Lessons from a TRPS1 mutation

A Thai mother and her two daughters were affected with tricho-rhino-phalangeal syndrome type I. The daughters had 15 and 18 supernumerary teeth, respectively. The mother had normal dentition. Mutation analysis of TRPS1 showed a novel heterozygous c.3809_3811delACTinsCATGTTGTG mutation in all. This mutation is predicted to cause amino acid changes in the Ikaros-like zinc finger domain near the C-terminal end of TRPS1, which is important for repressive protein function. The results of our study and the comprehensive review of the literature show that pathways of forming supernumerary teeth appear to involve APC and RUNX2, the genes responsible for familial adenomatous polyposis syndrome and cleidocranial dysplasia, respectively. The final pathway resulting in supernumerary teeth seems to involve Wnt, a morphogen active during many stages of development. © 2016 Wiley Periodicals, Inc.

Orthokeratinized Odontogenic Cyst with an Associated Keratocystic Odontogenic Tumor Component and Ghost Cell Keratinization and Calcifications in a Patient with Gardner Syndrome

Gardner syndrome (GS) is caused by mutations in the APC and besides adenomatous colorectal polyps includes such manifestations as osteomas, epidermoid cysts (ECs) and occasionally multiple pilomatricomas. More than 50 % of ECs in patients with GS exhibit pilomatricoma-like ghost cell keratinization. The latter may be explained by the fact that the development of both GS and pilomatricoma is driven by activation of the Wnt/β-catenin signaling pathway. A 62-year-old, Caucasian male with history of GS presented with a unilocular, mixed radiopaque/radiolucent mandibular lesion causing divergence and external root resorption of involved teeth. Histopathologically, the lesion was composed of two cystic components, an orthokeratinized odontogenic cyst (OOC) and a smaller one with characteristics of keratocystic odontogenic tumor (KCOT) featuring, focally, ghost cells and an epithelial morule-like structure. Dystrophic calcifications essentially similar to those seen in pilomatricomas were observed in the fibrous connective tissue wall. The KCOT and OOC epithelia revealed strong and diffuse cytokeratin (AE1/AE3) and β-catenin immunoreactivity. CD10 positive immunostaining was seen in the keratin and superficial spinous cell layers in both OOC and KCOT. The intraepithelial and mural ghost cells showed a cytokeratin (+), β-catenin and CD10 (-) immunophenotype. The diagnosis of OOC with ghost cell calcifications in association with KCOT was rendered. The patient was lost to follow-up. Although a coincidental co-existence cannot be excluded, ghost cell calcifications mimicking pilomatricoma-like changes in an unusual odontogenic cyst combining OOC and KCOT features as seen in this patient with GS may be explained by the common molecular mechanisms underlying the pathogenesis of cutaneous pilomatricomas and GS.

Oral manifestations in patients with familial adenomatous polyposis: A systematic review and meta-analysis

BACKGROUND AND AIM

The oral manifestations of familial adenomatous polyposis (FAP) have been reported in the recent literature. Therefore, there has been growing interest in the characterization of the dento-osseous anomalies because they may precede colorectal cancer and may be used as a diagnostic marker. This systematic review and meta-analysis was performed to evaluate the published evidence for what are the oral manifestations of FAP and their frequency in affected individuals.

METHODS

The search was performed at Cochrane Library, EMBASE, LILACS, PubMed, Scopus, and Web of Science for articles published up to March 2015. A grey literature search was conducted through Google Scholar. Reference lists of the included articles and additional studies identified by expert were screened for potential relevant studies. The methodology of selected studies was evaluated using the risk of bias checklist of the Agency for Healthcare Research and Quality.

RESULTS

Twenty observational studies totalizing 1635 individuals affected by FAP met the inclusion criteria. Osseous, dental, and oral mucosa alterations were observed in FAP patients. The meta-analysis showed the frequency of osseous jaw lesions, and the dental anomalies were 65.35% and 30.48%, respectively, and two studies suggested that oral mucosa vascular density is a phenotypic manifestation in patients with FAP. Most of the studies were evaluated as moderate risk of bias.

CONCLUSION

The most frequent oral manifestation on FAP patients is osseous jaw alterations. In the future, well-designed studies are necessary to classify osseous and dental anomalies in order to demonstrate the true prevalence of each alteration separately.

Oral and maxillofacial considerations in Gardner's syndrome: a report of two cases

Gardner's syndrome (GS) is a genetic disorder characterised by intestinal polyps, multiple osteomas, and soft-tissue tumours. Dentists play an important role in the syndrome diagnosis considering that craniomaxillofacial osteomas are a major criteria for Gardner's syndrome diagnosis. This study aimed to describe the main stomatological manifestation of GS and the importance of dentists in its diagnosis. Two patients presenting GS were evaluated. The first one had two osteomas in the mandible and GS was suspected. The colonoscopy confirmed the presence of polyposis and a prophylactic proctocolectomy was performed. The other patient had a late-stage diagnosis of GS and developed a rectum adenocarcinoma. The presence of craniomaxillofacial osteomas are a hallmark of the disease. Early-stage GS diagnosis may enable early diagnosis and preventive strategies in carriers. Other dental abnormalities, such as supernumerary teeth, hypercementosis and odontomas, can also be observed.

An Uncommon Case of Solitary Peripheral Osteoma in the Mandible

Osteoma is a benign osteogenic lesion which is composed of well differentiated mature compact and/or cancellous bone that proliferates continuously. Its prevalence is 4%. Its pathogenesis is still controversial. Solitary peripheral osteoma of craniofacial region is a rare finding. We report a case of 30-year-old female having solitary peripheral osteoma present on the lingual cortex of the left posterior mandible which was initially asymptomatic but now is causing discomfort while chewing and not associated with Gardner's syndrome. We also laid emphasis on its clinical, differential diagnosis, radiological, surgical, and histopathological features. The aim of this paper is to present an uncommon case of solitary peripheral osteoma in the mandible along with analysis of literature for peripheral osteomas of jaws and to contribute to the knowledge concerning the pathogenesis, differential diagnosis, and management of these lesions.

Hereditary Colorectal Cancer: Genetics and Screening

Colorectal cancer (CRC) is the third most common cancer and the third leading cause of cancer death in men and women in the United States. About 30% of patients with CRC report a family history of CRC. However, only 5% of CRCs arise in the setting of a well-established mendelian inherited disorder. In addition, serrated polyposis is a clinically defined syndrome with multiple serrated polyps in the colorectum and an increased CRC risk for which the genetics are unknown. This article focuses on genetic and clinical aspects of Lynch syndrome, familial adenomatous polyposis, and MUTYH-associated polyposis.

Gardner's Syndrome revisited: a clinical case and overview of the literature

Gardner's syndrome (GS), a variant of familial adenomatous polyposis (FAP), remains a life-threatening condition of significant dental relevance. Clinicians can play an important role in the identification of this condition as the dental manifestations often precede the development of intestinal polyposis. This article describes a clinical case in which identification of the dental features of GS during routine orthodontic assessment resulted in the early diagnosis of this condition, which was previously unrecognised in a young female patient.

Molecular and genetic aspects of odontogenic lesions

In this article we outline the molecular findings of select odontogenic tumors. In each section, we briefly review selected the clinicoradiographic, histologic, immunologic features, focusing on the molecular findings and their applications in practice. The understanding of molecular pathobiology at various other organ sites has developed quite rapidly in recent years, however much remains unknown about the genetic profile of odontogenic tumors. Improved understanding of mutations in odontogenic tumors may clarify classification schema and elucidate targets for novel therapies. Molecular testing will no doubt improve our understanding of odontogenic tumor pathogenesis and will likely be, someday, an important component of routine clinical practice and its role will only increase in the coming years.

Odontomas and supernumerary teeth: is there a common origin?

The aim of the present work is to analyze all scientific evidence to verify whether similarities supporting a unified explanation for odontomas and supernumerary teeth exist. A literature search was first conducted for epidemiologic studies indexed by PubMed, to verify their worldwide incidence. The analysis of the literature data shows some interesting similarities between odontomas and supernumerary teeth concerning their topographic distribution and pathologic manifestations. There is also some indication of common genetic and immuno-histochemical factors. Although from a nosological point of view, odontomas and supernumeraries are classified as distinct entities, they seem to be the expression of the same pathologic process, either malformative or hamartomatous.

Ameloblastic carcinoma with features of ghost cell odontogenic carcinoma in a patient with suspected Gardner syndrome

Ameloblastic carcinoma and ghost cell odontogenic carcinoma are rare malignancies arising in odontogenic epithelium within the jaws. Gardner syndrome is a multifaceted autosomal dominant condition, which results in multiple dentofacial anomalies along with premalignant colon polyp formation and tumor formation in the skin and other organs. We report a case of ameloblastic carcinoma with features of ghost cell odontogenic carcinoma and extensive clear cell change and melanin pigmentation in a patient with clinical features of Gardner syndrome. To the best of our knowledge, odontogenic carcinoma arising in a patient with features of Gardner syndrome has not been reported previously. The clinical, radiographic, and histologic features of the case are discussed along with a review of the relevant literature.

External manifestations of Gardner's syndrome as the presenting clinical entity

Gardner's syndrome is an autosomal dominant disease characterised by the presence of colonic polyposis, osteomas and a multitude of soft tissue tumours. Pathological features such as osteomas of the mandible, skull and facial skeleton are unaesthetic as well as incapacitating. We present the case of a 22-year-old man with pain and discharge from the left eye and a firm swelling in the left infraorbital region leading to proptosis of the left eye. A detailed examination of the patient led to the presence of a large osteoma in the left orbital region, multiple cystic lesion, corneal opacity and parapapillary atrophy in the left eye. Radiography revealed the presence of multiple unerupted supernumerary teeth and osteomas. Colonoscopic findings showed the presence of multiple polyps. Thus, external manifestations of the patient's facial region led to the establishment of the diagnosis of Gardner's syndrome. The importance of our case highlights the necessity of maintaining a high vigilance with regard to the occurrence of such an entity.

Revisiting peripheral osteoma of the mandible with case series and review of literature

Osteomas are benign lesions composed of mature compact and cancellous bone usually arising from craniofacial region. They can be central or peripheral, solitary or multiple. We are presenting few cases of giant peripheral osteoma's of the mandible along with review literature of other jaw lesions with their diagnostic features and differential diagnosis. The purpose of presenting this paper is to evaluate radiopaque lesions of the jaw which require proper clinical and histological evaluation to reach a final diagnosis.

Bilateral Sertoli cell tumors of the testis-a likely new extracolonic manifestation of familial adenomatous polyposis

Testicular Sertoli cell tumors are rare and usually sporadic and unifocal. The large cell calcifying Sertoli cell tumor variant is known to be associated with Carney and Peutz-Jeghers syndromes and can be bilateral in these patient populations. There has been no documented association of Sertoli cell tumor with familial adenomatous polyposis (FAP) in the literature. The case presented is a bilateral Sertoli cell tumor occurring in a 34-year-old patient with FAP. The tumor had a conventional Sertoli cell tumor morphology, but with different morphology in the left and right sites. Beta-catenin immunostain showed strong nuclear reactivity in the tumor cells but not the nonneoplastic Sertoli cells. The presence of bilaterality as well as overexpression of beta-catenin by this tumor supports an association of the development of Sertoli cell tumor with the patient's FAP syndrome and adenomatous polyposis coli inactivation.