Dental Agenesis Research Articles

Genotypic and phenotypic spectra of FGFR1, FGF8, and FGF17 mutations in a Chinese cohort with idiopathic hypogonadotropic hypogonadism

To analyze the prevalence of FGFR1, FGF8, and FGF17 mutations in a Chinese cohort with idiopathic hypogonadotropic hypogonadism (IHH) and to characterize the clinical presentations and therapeutic outcomes of IHH patients with FGFR1, FGF8, and FGF17 mutations. Retrospective cohort. University hospital. A total of 145 IHH probands (125 men and 20 women) were recruited for this study. Hormone assays. Whole-exome sequencing, polymerase chain reaction-Sanger sequencing, in silico functional prediction. Six novel mutations (p.154_158del, p.E496Rfs*12, p.W190X, p.S134D, p.W10X, and c.1552 + 3insT) in FGFR1, two novel mutations (p.E176K and p.R184C) in FGF8, three novel mutations (p.48_52del, p.P120L, and p.K191R) in FGF17, and five reported mutations (p.W289X, p.G237S, p.V102I, p.R250Q, and p.T340M) in FGFR1 were identified in 18 IHH patients. The functional consequences of all mutations were analyzed in silico. In addition to hypogonadotropic hypogonadism, 44.4% (8/18) patients exhibited other clinical deformities, including dental agenesis (3/18, 16.7%), hearing loss (3/18, 16.7%), and hand malformation (2/18, 11.1%). hCG/hMG therapy was effective in promoting sexual development in IHH patients with FGFR1, FGF8, and FGF17 mutations. We extended the mutational spectrum of FGFR1, FGF8, and FGF17 in IHH patients. The prevalence of FGFR1, FGF8, and FGF17 mutations in IHH was 12.4%. hCG/hMG therapy was effective to acquire fertility for patients with FGFR1, FGF8, and FGF17 mutations but has a risk of transmitting the mutations and IHH to the next generation.

Dental anomalies in craniofacial microsomia: A systematic review.

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

Assessment of oral health-related quality of life in adolescents, young adults, and adults with dental agenesis: A comparative study.

To detect the impact on oral health-related quality of life (OHRQoL) in adolescents, young adults, and adults with dental agenesis (DA). A comparative study (1:2) matched for age and sex was designed. Data of participants, aged 14-55 years (group with DA: G1; group without DA: G2), and who answered the Brazilian version of the Oral Health Impact Profile-14 questionnaire, were collected. One-way analysis of variance and Student's t-test were applied, considering p<.05 to be significant. The final sample consisted of 90 participants (G1=30; G2=60), with a mean age of 28.76 (±10.87) years. The mean scores in the G1 and G2 groups were 5.30±5.35 and 2.45±3.95, respectively. Comparing the means of both groups, in terms of the total score (p=.01), psychological discomfort (p=.04), psychological disability (p=.01), and social disability (p=.04) showed statistical differences. Evaluating G1, the age did not influence the negative impact on OHRQoL. The variables, years of study (≥9), DA severity, and location of DA in the anterior and posterior regions negatively influenced OHRQoL in different domains (p<.05). Despite low OHRQoL, DA generated negative impact on OHRQoL in adolescents/young adults, and adults.

Elements of morphology: Standard terminology for the teeth and classifying genetic dental disorders.

Dental anomalies occur frequently in a number of genetic disorders and act as major signs in diagnosing these disorders. We present definitions of the most common dental signs and propose a classification usable as a diagnostic tool by dentists, clinical geneticists, and other health care providers. The definitions are part of the series Elements of Morphology and have been established after careful discussions within an international group of experienced dentists and geneticists. The classification system was elaborated in the French collaborative network "TÊTECOU" and the affiliated O-Rares reference/competence centers. The classification includes isolated and syndromic disorders with oral and dental anomalies, to which causative genes and main extraoral signs and symptoms are added. A systematic literature analysis yielded 408 entities of which a causal gene has been identified in 79%. We classified dental disorders in eight groups: dental agenesis, supernumerary teeth, dental size and/or shape, enamel, dentin, dental eruption, periodontal and gingival, and tumor-like anomalies. We aim the classification to act as a shared reference for clinical and epidemiological studies. We welcome critical evaluations of the definitions and classification and will regularly update the classification for newly recognized conditions.

Nonsyndromic familial Oligodontia in a 13 year old male: A case report

The most common oral developmental anomaly is dental agenesis which can be either in the form of Anodontia, Oligodontia, or Hyperdontia. This can occur either as an isolated finding or as part of a syndrome. Nonsyndromic Oligodontia is rare. Early intervention and prompt management improves quality of life. Here, we report a case of a 13-year-old male child with non-Syndromic Oligodontia without any association with specific systemic disease who allegedly had complete set of primary teeth but failed to develop complete permanent dentition.

REGIONAL ODONTODYSPLASIA: A CASE REPORT

Objective Report a case of regional odontodysplasia in the maxilla of a pediatric patient and the immunohistochemical expression of different types of collagen. Regional odontodysplasia is a rare developmental anomaly, involving the ectoderm and ectomesenchyme of the temporally and permanent teeth. It tends to be locallizated in only one arch of the jaws. Case report A 8-year-old female patient, with no significant hereditary or pathological history. On examination dental agenesis C, D, E is observed. Radiographically revealed 6, 7 and 8 with radiopaque contour and loss of the delimitation between enamel-dentin complex, giving an appearance of ghost teeth. Surgical treatment was performed. Microscopic examination follicular tissue contains scattered collection of enameled congregates and islands of odontogenic epithelium. Immunohistochemical expression of different types of collagens was heterogeneous in the dentin (col. 1,2,3,4,5,6,10 and 11). These results are consistent with an abnormal dentin development. Conclusion Regional odontodysplasia is an alteration that develops at a very early age, so the interdisciplinary management and the choice of treatment are fundamental since the treatment must be specific for each patient.

Tooth autotransplantation using nylon yarns as fixation - a case report

Background: Dental autotransplantation consists of extracting an impacted or partially erupted tooth from the individual and transplantation from one site to another. The advantage of this approach is the possibility of rehabilitating the patient using autologous biological material. This procedure is indicated for replacement of teeth that will undergo exodontia for several reasons: impacted teeth whose orthodontic mechanics is not possible, ectopic teeth, premature tooth loss due to trauma or caries, and dental agenesis. Transplanted teeth have a favorable prognosis in developing patients and are capable and may even establish proprioception during the healing process. The positive prognosis is influenced by the patient's age, dental development stage, donor tooth root anatomy, alveolar preservation, adequate surgical technique and correct postoperative stabilization. The most common complications for this technique are pulp necrosis, root resorption, dental ankylosis and lack of periodontal insertion. L.A. Machado, R.R. do Nascimento, D.M.T.P. Ferreira, C.T. Mattos, O.V. Vilella: Long-term prognosis of tooth autotransplantation: a systematic review and meta-analysis. Int. J. Oral Maxillofac. Surg. 2016; 45: 610–617. K. Almpani, S.N. Papageorgiou, M.A. Papadopoulos: Autotransplantation of teeth in humans: A systematic review and meta-analysis. Clin Oral Invest. 2015; 19: 1157–1179 (OSA).

Avaliação da prevalência de agenesia de incisivos laterais superiores dos pacientes da Faculdade de Odontologia do Centro Universitário da Serra Gaúcha

A agenesia dentária pode ser definida como a falta de desenvolvimento do dente, com a ausência de um até seis dentes, sendo bastante frequente nas dentições decídua e permanente. A etiologia está relacionada tanto à fatores genéticos quanto a ambientais. Quanto maior a contribuição genética na origem de uma alteração, menor a possibilidade de prevenir, assim, pior o prognóstico do tratamento. Com o diagnóstico precoce, consegue-se uma intervenção ortodôntica em uma época adequada. Objetivo: Avaliar a prevalência de agenesia de incisivos laterais superiores (ILS) em radiografias panorâmicas da Faculdade de Odontologia do Centro Universitário da Serra Gaúcha. Métodos: estudo transversal de prevalência realizado no laboratório de Interpretação Radiográfica da FO-FSG envolvendo radiografias panorâmicas realizadas nos anos de 2015 a 2017. Foram registrados dados relativos ao número do prontuário do paciente, idade, sexo do indivíduo, a presença ou não de agenesia, o dente ausente, a presença ou não de diminuição de tamanho e apresentação de anomalia conoíde. Resultados: Nas amostras aplicou-se o teste Qui-quadrado para a heterogeneidade. Verificou-se que o gênero e a agenesia não estão significativamente associados (p&lt;0,05). Conclusão: Os indivíduos com agenesia de ILS, não apresentam diferenças entre os lados e os gêneros. Constata-se que a agenesia bilateral do ILS, é mais frequente do que a agenesia unilateral.

SUN-219 Human Congenital Arhinia Is Associated with GnRH Deficiency and Primary Testicular Defects

Congenital arhinia (absent external nose) is an extremely rare mendelian disorder (<100 case reports in the past century) caused by heterozygous missense mutations in the gene SMCHD1. Arhinia is frequently accompanied by ocular and reproductive defects, a clinical triad which defines the Bosma arhinia microphthalmia syndrome (BAMS). The etiology and spectrum of reproductive defects in BAMS is unknown. We studied eleven subjects with arhinia or nasal hypoplasia (aged 18-53 yrs; 5 males) to assess endogenous luteinizing hormone (LH) secretion (n=11), a validated marker of GnRH, responsiveness to pulsatile GnRH (n=2), and non-reproductive phenotypes (n=11). Clinical data abstracted from questionnaires were analyzed in 33 additional international patients. Nearly every male demonstrated clinical and biochemical signs of severe congenital GnRH deficiency (CGD) including a history of microphallus and/or cryptorchidism, testicular volumes < 3 ml, hypogonadotropic hypogonadism (HH), low inhibin B levels, and apulsatile LH profiles; two young boys (studied from afar) had normal genitals but an absent mini-puberty of infancy was confirmed biochemically in one case. Pulsatile GnRH administered to one adult male and hCG to two others also revealed testicular resistance. Several females reported spontaneous breast bud development, but all had primary amenorrhea, small ovaries on pelvic ultrasound, HH, and apulsatile LH profiles. Pulsatile GnRH administered to one female induced ovulation on treatment day 21. Two females (studied from afar) reported normal thelarche and menstrual cycles. The 11 subjects studied in detail were completely anosmic with absent internal olfactory structures on brain MRI but normal hypothalamic-pituitary anatomy. Subjects with arhinia demonstrated some, but not all, non-reproductive phenotypes characteristic of Kallmann syndrome (KS) and/or CHARGE syndrome including dental agenesis (56%) and congenital mirror movements (CMMs; 50%); none had renal agenesis, severe congenital heart defects, or deafness. This study demonstrates for the first time that the hypogonadotropism observed in BAMS is indeed secondary to GnRH deficiency. In contrast to the male predominance (3-5:1) in KS, there is no sex bias in the incidence of BAMS. However, females may demonstrate partial or complete pubertal development whereas males are severely affected with some showing both hypothalamic and testicular defects. The combination of defects in the nasal skeleton, olfactory structures, and GnRH ontogeny point to aberrant development of the nasal placode in BAMS, yet the high prevalence of CMMs, a sign of misrouted commissural axons, suggests insults may occur even earlier in neurogenesis, at the neural plate border.

Syndromes associated with dental agenesis.

Dental agenesis is the congenital absence of a variable number of teeth due to the lack of formation of the corresponding tooth germ. The aim of this work was to investigate the syndromic conditions characterized by dental agenesis. Based on the research conducted through the OMIM® (Online Mendelian Inheritance in Man) and PubMed online databases, more than ninety syndromes associated with severe or moderate agenesis have been found. The main clinical features of these syndromes are described, especially those concerning the stomatognathic apparatus, referring to the most recent literature. Among these syndromes there are three clinical conditions associated with dental agenesis that are common for the clinician: Down Syndrome, ectodermal dysplasia and labio-palatal cleft. It must be kept in mind that the success of the treatment of these patients is based on the compliance of the patient as well as on the collaboration among specialists.

Association between Dental Agenesis and Cancer-A Systematic Review of Literature

Association between Dental Agenesis and Cancer-A Systematic Review of Literature

Prevalence and distribution of dental agenesis among orthodontic patients of Kathmandu, Nepal

Background: Tooth agenesis is the most common developmental dental anomaly in humans with a wide variability of distribution among different population. Objective: The objective of this study was to find out the prevalence of dental agenesis among Nepalese orthodontic patients of Kathmandu and its occurrence with relation to gender, sides, and jaw. Materials and Methods: This study consisted of 601 patients (242 males and 359 females) aged between 10 and 35 years who require orthodontic treatment. Dental panoramic radiographs were evaluated for dental anomalies causing disturbance in number by a trained observer who followed a preestablished protocol. Chi-square test was used to determine the difference in the prevalence of dental agenesis between genders, sides, and jaws. Results: The prevalence of dental agenesis was 7.48% (45) while excluding the third molar and 27.62% (166) while including the third molar. The prevalence of oligodontia was 0.33% (2). The total number of missing teeth including the third molar was 371 and it was 72 while excluding the third molar. Maxillary lateral incisor was the most lost (48.61%) followed by mandibular lateral incisor (19.44%), mandibular central incisor (8.33%), mandibular second premolar (6.94%), and maxillary second premolar (5.55%) while excluding the third molars. There was no statistically significant difference in the prevalence of missing teeth in between gender (P = 0.996), in between right and left sides (P = 0.590), and in between upper and lower jaws (P = 0.010). Conclusion: The most common missing teeth were maxillary lateral incisor followed by mandibular lateral incisor, mandibular central incisor, and mandibular second premolar. Orthodontists have the responsibility to observe each patient carefully for dental agenesis and have full knowledge to plan the best possible treatments.

Digital smile designing, pressing and stratifying ceramic lithium disilicate veneers to rehabilitate dental agenesis: a clinical report

ABSTRACT This article had the objective of reporting a case of aesthetic rehabilitation with laminated facets from the 14 to the 24 teeth made with IPS E.max Ceram ceramics (Ivoclar-Vivadent), which replaced previous unsatisfactory composite resin restorations in the anterior region. The patient had agenesis of 12 and 22 teeth, making it necessary to anatomize the anterior teeth. A digital smile design was first virtually created and then followed by a diagnostic wax-up. The following was performed in a single day: periodontal surgery using the flapless technique to achieve prosthetic space; teeth preparation; an additionalsilicone impression; and multiple provisional restorations of bis-acryl composite resins were fabricated. Fourteen days later, in the second session the ceramic veneers were etched with 5% hydrofluoric acid for 20s; they received a silane application and a silane heat treatment, then lastly an ultrasonic bath. A universal adhesive was used in combination with a light curing cement.Cementation was performed immediately following an occlusal adjustment. The patient returned for a follow-up appointment another fourteen days after the luting process, in which a further occlusal adjustment was performed, and he reported complete satisfaction with the treatment.

Prevalence of Hypodontia in Unilateral and Bilateral Cleft Lip and Palate Patients Inside and Outside Cleft Area: A Case-Control Study.

The aim of this study is to evaluate the prevalence and distribution of hypodontia, inside and outside the cleft area, in an Italian population with a non-syndromic unilateral (UCLP) and bilateral (BCLP) cleft lip and palate on panoramic radiographs and comparing it with a control sample. Case group was ethnically uniform and consisted in 233 patients. The control group was composed of 1000 subjects. Patients included were between seven and fifteen years old. Descriptive analysis, using absolute and relative frequencies, was performed to check out the prevalence of gender distribution, hypodontia and cleft formation. Statistical analysis was conducted with Chi-squared test, Yate's correction and the Fisher's exact test. The power was set higher than 0.8 for each test. 160 cleft patients (68.68%) presented at least one missing tooth, while 88 patients in the control groups presented agenesis (8.80%). A statistically significant difference was found in case and control groups for upper lateral incisors (37.34% and 48.07% in the case group against 2.50% and 2.60% in the control group), upper and lower second premolars (8.58%, 6.44%, 5.58% and 6.01% in the cleft group and 0.60%, 0.60%, 2.50% and 2.70% in the control group). Higher prevalence of dental agenesis in the maxillary dental arch is explained by the cleft defect. Higher prevalence of mandibular second premolars agenesis cannot be explained by the anatomical defect and suggests a multifactorial aetiology, including environmental and genetic factors, of the cleft condition.

Symmetry of dental agenesis in Down Syndrome children

Background/purposeDown syndrome (DS) may affect the mouth, influencing its function, feeding and hence overall health status. We aim at investigating the frequency and type of dental agenesis in a school-age DS sample, evaluating gender, laterality, upper or lower side, and mono- or bi-laterality. Materials and methodsOral clinical and radiological exams were performed. Forty-six (20 female and 26 male) panoramic radiographs, done when DS patients were 8–12 years old, were examined, from patients between 3 and 25 years old at the first visit. ResultsThe percentage of missing teeth was compared with chi-squared test: 65% of patients presented agenesis of one or more teeth. The most frequently missing teeth were the upper left lateral incisor, the lower second premolars and the upper right lateral incisor. Usually, the absence was bilateral. There was no difference between sexes, between mandible and maxilla, either in the left or in the right side. ConclusionA high occurrence of dental agenesis was observed in DS patients: some teeth were mostly affected and bilateral agenesis was frequent. Due to the high prevalence of teeth agenesis in DS patients, special care is devised for correct development of oral functions and for avoidance of oral pathologies.

Novel dental phenotype in non-syndromic Pierre Robin Sequence: A retrospective study

ObjectiveThe objective was to investigate dental phenotypes in individuals with non-syndromic Pierre Robin Sequence (ns-PRS) and compare the prevalence of these phenotypes with subjects with non-syndromic cleft palate (ns-CP) and a control group with subjects without any craniofacial anomalies. MethodsA total of 760 panoramic radiographs of 330 individuals (110 with ns-PRS; 110 with ns-CP and 110 without any malformations) were digitized and evaluated regarding the diagnosis of taurodontism, tooth agenesis, root dilaceration and tooth transposition. Chi-square test was applied to compare the occurrence of dental phenotypes between groups. A P value of less than 0.05 was considered statistically significant. ResultsTotal prevalence of dental phenotypes was 94.5% of ns-PRS; 54.5% of ns-CP and 59.1% of the control group subjects with a statistically significant difference for the ns-PRS when compared to the other two groups. Two dental phenotypes, taurodontism and dental agenesis were identified with statistically significant higher prevalences in subjects with ns-PRS when compared with the ns-CP group and the control group (p < 0.001). Taurodontism was the most prevalent dental phenotype, with 92.73% in the ns-PRS group, 40.91% for ns-CP and 44.55% in the control group. Tooth agenesis had a prevalence of 22.7% for ns-PRS, 4.5% for ns-CP and no case in the control group. For the prevalence of root dilaceration and tooth transposition, no statistically significant differences were observed between the three groups. ConclusionsDue to the high frequency of taurodontism in individuals with ns-PRS, we suggested that this novel phenotype would be important in the phenotypic screening of ns-PRS and could be considered as a phenotype associated with ns-PRS.

A radiographic assessment of the prevalence and pattern of dental agenesis in a Nigerian population

Objective: Dental agenesis is responsible for dental presentation for orthodontic, restorative and prosthodontic reasons. This study presents the prevalence and pattern of permanent tooth agenesis in a group of Nigerian patients. Methods: Orthopantomograms of orthodontic patients were assessed for missing permanent teeth. Demographic data was obtained, and the prevalence and pattern of individual tooth agenesis presented. The relationship between dental agenesis and gender, jaw as well as side affected was assessed using the Chi square test while the Student's T-test was used to assess the variation in number of missing teeth across the genders. Data was analysed using the SPSS version 22. Statistical significance was set at p<0.05. Results: Tooth agenesis including third molars was observed in 37(17.1%) while exclusion of the third molars gave an agenesis prevalence of 10.2% in 22 patients. There was no significant difference in the prevalence of dental agenesis based on gender whether third molars were considered or not (p=0.77 and p=0.37). There was no significant difference in mean number of missing tooth per person based on gender whether third molars were considered (p=0.12) or excluded from analysis (p=0.26). There was significant difference in the type of tooth involved in agenesis and the arch affected (p=0.01). Conclusion: The prevalence of dental agenesis among this group of patients is comparable with that from other populations. Excluding third molars, incisors are more predisposed to agenesis in the maxilla, while premolars are more likely not to develop in the mandible. Keywords: Agenesis, prevalence, pattern, Nigeria

Novel rare variations in IRF6 in subjects with non-syndromic cleft lip and palate and dental agenesis.

Subjects with cleft lip and palate (CLP) present high prevalence of dental agenesis. Among candidate genes for these phenotypes is IRF6. However, genetic studies do not analyze dental agenesis as a phenotype associated with cleft. Therefore, we investigated the frequency of rare and novel variations in IRF6 in subjects with non-syndromic unilateral cleft lip and palate (NSUCLP), with and without dental agenesis. Genomic DNA samples of 100 subjects with NSUCLP with and without dental agenesis and 50 controls were sequenced. IRF6 mutational screening was conducted by direct sequencing. Ten new and rare missense variations were identified, two in the group cleft with agenesis and eight in the group cleft without agenesis, and none were found in control group. In silico analysis revealed four variations as potentially deleterious, being two in the group with cleft and agenesis and two in the group with cleft without agenesis. The study identified novel IFR6 variations in subjects with NSUCLP with or without associated dental agenesis. The hypothesis of a higher frequency of deleterious variations in the subjects with cleft associated with dental agenesis, when compared to the group of cleft without agenesis and control without cleft, was not supported.

Impact of Hematopoietic Stem Cell Transplantation on Dental Development

To investigate dental development in patients treated with a hematopoietic stem cell transplantation (HSCT), 42 children and young adults who were under 12 years old at time of HSCT were examined for dental agenesis, microdontia, and root-to-crown ratio. Conditioning regimens were total body irradiation (TBI) based in 12 patients, busulfan based in 21 patients, and 9 patients had other chemotherapeutic agents. Sixteen patients were <3 years old, 9 patients were 3 to 6 years old, and 17 patients were 6 to 12 years old at HSCT. Prevalence of agenesis and microdontia of at least 1 permanent tooth were, respectively, 51.3% and 46.2% in the study population, and 76.3% had an aberrant root-to-crown ratio. All these results were highly different from the prevalence in the healthy population. Patients treated before the age of 3 years had more microdontia (76.9%) and agenesis (92.3%) compared with patients treated at an older age. In the subgroup of patients treated after 6 years, there was more microdontia when treated with busulfan (50%) compared with treatment with TBI (0%) (P = .044). Patients treated with HSCT had many disturbances in dental development. Age at HSCT and possibly also the conditioning regimen used had an effect on their type and prevalence. Dental follow-up should be incorporated in the multidisciplinary follow-up program of these patients.

Dentinogenesis imperfecta type II in Swedish children and adolescents

BackgroundDentinogenesis imperfecta (DGI) is a heritable disorder of dentin. Genetic analyses have found two subgroups in this disorder: DGI type I, a syndromic form associated with osteogenesis imperfecta (OI), and DGI type II, a non-syndromic form. The differential diagnosis between types I and II is often challenging. Thus, the present cross-sectional study had two aims: to (i) investigate the prevalence and incidence of DGI type II among Swedish children and adolescents and (ii) search out undiagnosed cases of DGI type I by documenting the prevalence of clinical symptoms of OI in these individuals. We invited all public and private specialist pediatric dental clinics (n = 47) in 21 counties of Sweden to participate in the study. We then continuously followed up all reported cases during 2014−2017 in order to identify all children and adolescents presenting with DGI type II. Using a structured questionnaire and an examination protocol, pediatric dentists interviewed and examined patients regarding medical aspects such as bruising, prolonged bleeding, spraining, fractures, hearing impairment, and family history of osteoporosis and OI. Joint hypermobility and sclerae were assessed. The clinical oral examination, which included a radiographic examination when indicated, emphasized dental variables associated with OI.ResultsThe prevalence of DGI type II was estimated to be 0.0022% (95% CI, 0.0016–0.0029%) or 1 in 45,455 individuals. Dental agenesis occurred in 9% of our group. Other findings included tooth retention (17%), pulpal obliteration (100%), and generalized joint hypermobility (30%). Clinical and radiographic findings raised a suspicion of undiagnosed OI in one individual, a 2-year-old boy; he was later diagnosed with OI type IV.ConclusionsThese results show a significantly lower prevalence of DGI type II than previously reported and point to the importance of excluding OI in children with DGI.