Epileptic encephalopathy and amelogenesis imperfecta: What about KohlschüttereTönz syndrome? Case report and literature review

BACKGROUND

KohlschüttereTönz syndrome (KTS), also called amelo-cerebro-hypohidrotic syndrome, is a very rare genetic condition, described for the first time by Kohlschutter, which typically manifests as a triad of symptoms:  amelogenesis imperfecta, infantile onset epilepsy, and intellectual disability. 47 cases were reported in English language literature since 1974-2021.

CASE REPORT

A 7-year-old girl was referred for dental evaluation. Oral examination revealed yellowish color of all the teeth due to enamel hypoplasia. The radiographic exam revealed a thin layer of enamel with decreased radiopacity of the enamel compared to that of dentin. The diagnosis of amelogenesis Imperfecta was established. In addition to that, the child's parents reported that she had spasticity, epileptic seizures and psychomotor developmental delay. The association of all these features leads us to conclude to KTS.

CONCLUSION

It seems that numerous cases of KTS are still undiagnosed in the world, so this paper highlights the common clinical features of Kohlschütter-Tönz Syndrome helping to an early diagnosis and more research about this condition.

Enamel Renal Gingival Syndrome in an Adolescent

Enamel renal gingival syndrome is a rare clinical condition characterized by the presence of amelogenesis imperfecta hypoplastic type, gingival fibromatosis and delayed tooth eruption, in addition to nephrocalcinosis with normal blood calcium levels. It is inherited as an autosomal recessive trait caused by mutations in the FAM20A gene located on chromosome 17q24.2. The purpose of this report is to describe a case of enamel renal gingival syndrome and discuss its distinct features and management.

Ophthalmic Manifestations of Heimler Syndrome in Two Siblings With PEX1 Variants

PURPOSE

To report two new cases with confirmed diagnosis of Heimler syndrome and describe their systemic and ophthalmic phenotype and visual rehabilitation.

METHODS

Retrospective review of medical records.

RESULTS

Both siblings were diagnosed as having sensori-neural hearing loss and retinal dystrophy with exuberant intraretinal cystoid spaces and cone-rod dysfunction. The older sibling also had amelogenesis imperfecta and neither had nail abnormalities. Genetic analysis identified homozygosity for the pathogenic variant c.2528G>A p.(Gly843Asp) in the PEX1 gene in both siblings. The parents were heterozygous carriers of the variant.

CONCLUSIONS

The authors report a familial case of Heimler syndrome due to biallelic PEX1 pathogenic variants that manifested as macular dystrophy characterized by cone-rod dysfunction and complicated by intraretinal cystoid spaces. Review of the literature shows that ocular phenotype is variable in patients with Heimler syndrome. [J Pediatr Ophthalmol Strabismus. 2024;61(1):59-66.].

Association between malocclusions and amelogenesis imperfecta genotype and phenotype: A systematic review

INTRODUCTION

The aim of this systematic review (Prospero CRD42022323188) is to investigate whether an association exists in patients with amelogenesis imperfecta (AI) between occlusal characteristics and genotype on the one hand and enamel structural phenotype on the other.

MATERIAL AND METHODS

Reports up to May 2023 assessing occlusion of individuals with AI were browsed in a systematic search using Medline, Embase, ISI Web of Science, and the grey literature. Randomised control trials, case control studies, and case series specifying both occlusion, assessed by cephalometric or clinical analysis, and genotype or dental phenotype in patients with AI were included without any age limitation. Two authors independently selected the publications and extracted the data in accordance with the PRISMA statement. The risk of bias was assessed with the Critical Appraisal Checklists from the Johanna Briggs Institute.

RESULTS

Twenty-five articles were chosen from the 261 results. Most of the included publications were case series (n=22) and case control studies (n=3). Thirteen studies reported both a genotype (ENAM, FAM83H, FAM20A, DLX3, CNMM4, WDR72) and occlusal diagnostic. The methodological quality of the studies was moderate. All AI phenotypes showed an open bite (OB) rate around 35%, except mixed form. The other malocclusions were not often mentioned. No correlation between occlusal phenotype and genotype or AI phenotype could be identified in patients with AI, as most studies had short occlusal descriptions and small sample sizes.

CONCLUSION

OB malocclusions were more frequently reported in AI. This review highlighted the need for a more accurate description of orofacial features associated with AI, to better clarify the role of amelogenesis genes in the regulation of craniofacial morphogenesis and identify patients requiring orthognathic surgery at an early stage.

Autoimmune amelogenesis imperfecta in patients with APS-1 and coeliac disease

Ameloblasts are specialized epithelial cells in the jaw that have an indispensable role in tooth enamel formation-amelogenesis1. Amelogenesis depends on multiple ameloblast-derived proteins that function as a scaffold for hydroxyapatite crystals. The loss of function of ameloblast-derived proteins results in a group of rare congenital disorders called amelogenesis imperfecta2. Defects in enamel formation are also found in patients with autoimmune polyglandular syndrome type-1 (APS-1), caused by AIRE deficiency3,4, and in patients diagnosed with coeliac disease5-7. However, the underlying mechanisms remain unclear. Here we show that the vast majority of patients with APS-1 and coeliac disease develop autoantibodies (mostly of the IgA isotype) against ameloblast-specific proteins, the expression of which is induced by AIRE in the thymus. This in turn results in a breakdown of central tolerance, and subsequent generation of corresponding autoantibodies that interfere with enamel formation. However, in coeliac disease, the generation of such autoantibodies seems to be driven by a breakdown of peripheral tolerance to intestinal antigens that are also expressed in enamel tissue. Both conditions are examples of a previously unidentified type of IgA-dependent autoimmune disorder that we collectively name autoimmune amelogenesis imperfecta.

Pathogenesis of Enamel-Renal Syndrome Associated Gingival Fibromatosis: A Proteomic Approach

The enamel renal syndrome (ERS) is a rare disorder featured by amelogenesis imperfecta, gingival fibromatosis and nephrocalcinosis. ERS is caused by bi-allelic mutations in the secretory pathway pseudokinase FAM20A. How mutations in FAM20A may modify the gingival connective tissue homeostasis and cause fibromatosis is currently unknown. We here analyzed conditioned media of gingival fibroblasts (GFs) obtained from four unrelated ERS patients carrying distinct mutations and control subjects. Secretomic analysis identified 109 dysregulated proteins whose abundance had increased (69 proteins) or decreased (40 proteins) at least 1.5-fold compared to control GFs. Proteins over-represented were mainly involved in extracellular matrix organization, collagen fibril assembly, and biomineralization whereas those under-represented were extracellular matrix-associated proteins. More specifically, transforming growth factor-beta 2, a member of the TGFβ family involved in both mineralization and fibrosis was strongly increased in samples from GFs of ERS patients and so were various known targets of the TGFβ signaling pathway including Collagens, Matrix metallopeptidase 2 and Fibronectin. For the over-expressed proteins quantitative RT-PCR analysis showed increased transcript levels, suggesting increased synthesis and this was further confirmed at the tissue level. Additional immunohistochemical and western blot analyses showed activation and nuclear localization of the classical TGFβ effector phospho-Smad3 in both ERS gingival tissue and ERS GFs. Exposure of the mutant cells to TGFB1 further upregulated the expression of TGFβ targets suggesting that this pathway could be a central player in the pathogenesis of the ERS gingival fibromatosis. In conclusion our data strongly suggest that TGFβ -induced modifications of the extracellular matrix contribute to the pathogenesis of ERS. To our knowledge this is the first proteomic-based analysis of FAM20A-associated modifications.

Non-syndromic occurrence of true generalized microdontia with hypodontia: A case report

RATIONAL

Dental abnormalities can occur at any stage of tooth development. Of these abnormalities, true generalized microdontia is a rare condition in which all teeth are smaller than normal, while hypodontia is defined as the absence of 1 to 5 teeth. As far as we are aware, no article has reported a case of the non-syndromic occurrence of true generalized microdontia with hypodontia.

PATIENT CONCERNS

A 9-year-old girl who had no systemic diseases presented with congenital absence of maxillary lateral incisors bilaterally and small teeth involving the whole dentition.

DIAGNOSES

Based on intraoral examinations and panoramic radiograph, the patient was diagnosed with the simultaneous occurrence of true generalized microdontia, hypodontia, and a variation of maxillary 1st molar with a single root and single canal. Also, the patient had premature loss of mandibular molars and canines, periapical periodontitis in the mandible left 1st primary molar and deep caries in mandible left secondary primary molar.

INTERVENTIONS

A removable appliance to hold space for early loss of mandibular molars and canines was made at the present stage. The mandible left 1st primary molar had periapical periodontitis and the affected tooth was extracted. Furthermore, the distal surface of the mandible left 2nd primary molar was filled with complex resin materials. A multi-disciplinary therapy plan was carefully designed including orthodontics, dental implants and esthetic restoration in the future.

OUTCOMES

The patient complied well with instructions for wearing the removable space maintainer, which helps prevent mesial migration of the permanent 1st molars, at the current stage. The therapeutic efficiency on periapical periodontitis and caries lesions was also good.

LESSONS

The non-syndromic presence of true generalized microdontia is extremely rare. A personalized treatment plan with multi-disciplinary considerations should be given for these patients. The pathogenesis remains unclear but may be related to genetic as well as environmental factors. More studies are urgently needed to explore the pathogenesis and treatment options for the future.

Weaker dental enamel explains dental decay

Dental caries continues to be the most prevalent bacteria-mediated non-contagious disease of humankind. Dental professionals assert the disease can be explained by poor oral hygiene and a diet rich in sugars but this does not account for caries free individuals exposed to the same risk factors. In order to test the hypothesis that amount of amelogenin during enamel development can influence caries susceptibility, we generated multiple strains of mice with varying levels of available amelogenin during dental development. Mechanical tests showed that dental enamel developed with less amelogenin is "weaker" while the dental enamel of animals over-expressing amelogenin appears to be more resistant to acid dissolution.

Conservative orthodontic treatment for skeletal open bite associated with amelogenesis imperfecta

Amelogenesis imperfect (AI) is a hereditary dental condition that affects tooth enamel, resulting in small and discolored teeth, tooth sensitivity, poor esthetics, and anterior open bite associated with severe discrepancy in the vertical relation of the jaws. Treatment can be complex and includes an interdisciplinary approach involving orthodontics, oral surgery, and restorative therapy. The purpose of this report is to describe the case of a 12-year-old girl with AI and severe open bite who received conservative, non-surgical therapy that led to good functional occlusion and acceptable dental and facial esthetics. A three-year follow-up showed excellent post-treatment stability.

Conservative treatment for amelogenesis imperfecta: a case report

Amelogenesis imperfecta is a hereditary condition that can alter the thickness, color, and shape of tooth enamel. Recent adhesive materials and techniques have provided less invasive treatment options. This case report presents the treatment of a patient whose anterior teeth had color alterations, white spots, pits, and shape defects. Using a more conservative technique, the mandibular and maxillary anterior teeth were restored using veneer direct composite restorations. After 6 years, the restorations demonstrated no deterioration, and no pathology was seen in association with the rehabilitation.

Amelogenesis imperfecta with bilateral nephrocalcinosis

A 12-year-old patient presented with a severe delay of eruption in permanent maxillary and mandibular incisors. On examination, there was over-retained primary teeth and delayed eruption of permanent teeth. Retained primary teeth showed light yellow discolouration whereas permanent teeth were distinct yellow with thin or little enamel. Subsequent imaging revealed all the premolars except maxillary left first premolar showed signs of intra-alveolar coronal resorption, nephrocalcinosis with bilateral multiple calculi and small papillary tip calcifications, marked increase in alkaline phosphatase. Subsequent dental treatment for restoring the functional and aesthetic requirement followed by appropriate treatment for renal problem was undertaken.

The restoration of function and esthetics of a patient with amelogenesis imperfecta using a combination of orthodontic and prosthodontic treatment: a case report

AIM

The purpose of this case report is to present the esthetic and functional rehabilitation of the teeth in a 20-year-old patient with amelogenesis imperfecta (AI), facial asymmetry due to functional mandibular shift, and unilateral posterior crossbite.

BACKGROUND

AI is a group of hereditary defects of enamel unassociated with any other generalized defects. AI results in poor development or the complete absence of the enamel of the teeth caused by improper differentiation of ameloblasts.

CASE DESCRIPTION

This report describes the diagnosis and treatment of a young female patient with AI and facial asymmetry using a combined orthodontic-prosthodontic approach. Initially, the posterior crossbite, mandibular shift, and facial asymmetry were treated orthodontically. Later, metal-ceramic crowns for posterior teeth and all-ceramic crowns for anterior teeth were fabricated for final restorations.

SUMMARY

Coordinated orthodontic and prosthodontic treatment, with careful consideration of patient expectations and requests, were critical for a successful outcome and patient satisfaction.

CLINICAL SIGNIFICANCE

The complexity of the management of patients with AI supports the suggestion that the dental profession should have appropriate methods for the rehabilitation of rare dental disorders.

Overdenture as a restorative option for hypocalcified-hypoplastic amelogenesis imperfecta: a case report

AIM

The aim of this report is to describe the restorative treatment of an 18-year-old patient diagnosed with autosomal recessive hypocalcified-hypoplastic amelogenesis imperfecta (AI).

BACKGROUND

Esthetic and functional rehabilitations in AI cases are challenging and should consider individual aspects, such as age, socioeconomic status, AI type, and intraoral condition.

REPORT

AI was diagnosed in an 18-year-old patient.

SUMMARY

Considering the short length of crowns and roots, patient life expectancy, minimal invasiveness, amount of treatment time required, and lower costs, oral rehabilitation with overdentures provided an adequate functional and esthetic rehabilitation of the patient.

CLINICAL SIGNIFICANCE

This report demonstrated overdentures to be a viable, relatively inexpensive, and non-invasive treatment choice of a patient with AI with concerns about treatment longevity, invasiveness, cost, esthetics, and long-term maintenance.

Interdisciplinary approach to treating a patient with amelogenesis imperfecta: a clinical report

Treatment of a patient with amelogenesis imperfecta (AI) presents a real problem from both functional and esthetic points of view. An esthetic result also will result in an improvement in the patient's quality of life. This clinical report illustrates the oral rehabilitation of a 24-year-old man diagnosed with hypomature type of AI. The aim of treatment was to both restore esthetics and improve masticatory function. Esthetic expectations of the patient were successfully attained by placing all-porcelain crowns from canine to canine in each arch, 12 crowns total. Moreover, metal-ceramic three-unit fixed partial dentures for the missing mandibular right first molars were fabricated for the patient's masticatory function. Resin composite restorations were applied to the maxillary premolars, the maxillary right first molar, the mandibular left premolars, and the right first premolar to modify the occlusion. No deterioration in the restorations and no pathology associated with the rehabilitation were found at the 1-year recall, and the patient's esthetic and functional expectations were satisfied. CLINICAL SIGNIFICANCE This article provides an overview of an interdisciplinary approach to treating the difficult condition of AI using a combination of treatments to achieve optimal esthetics and function.

Severely hypoplastic amelogenesis imperfecta with taurodontism

BACKGROUND

The prominent dental feature of a boy was severely hypoplastic enamel in both primary and permanent teeth.

CASE REPORT

Many permanent teeth were already infected while emerging in the oral cavity. Panoramic radiograph showed enlarged and elongated pulp chambers (taurodontism) in the permanent first molars. The clinical and radiological diagnosis was either hypomaturation-hypoplastic amelogenesis imperfecta with taurodontism (AIHHT) or tricho-dento-osseous syndrome (TDO). Histological examination of the upper right permanent first molar revealed thin lamellar or somewhat thicker amorphous enamel on approximal surface only with no rods or incremental lines visible. Histologically, the Witkop type AIG designated 'enamel agenesis' cannot be excluded. The medical and dental history of the family members, as well as the boy's medical examination, was noncontributing. He had thick, blond, curly hair. The bone structure of the jaws and skull was normal. For genetic analysis, DLX3 gene was sequenced but no mutation was found.

CONCLUSIONS

Since the gene defect of TDO has been localized only in the DLX3 gene, the more probable diagnosis was AI.

Is amelogenesis imperfecta an indication for renal examination?

BACKGROUND

The term 'amelogenesis imperfecta' (AI) describes a diverse group of hereditary conditions primarily affecting the quality and/or quantity of dental enamel.

CASE REPORT

This paper describes a case in which hypoplastic AI with delayed/failure of eruption of the permanent teeth was shown to be associated with renal calcification.

CONCLUSION

Given the importance of the renal involvement, the authors suggest that paediatric dentists consider referring all children with this dental phenotype for renal ultrasound examination.

Restorative therapy of primary teeth severely affected by amelogenesis imperfecta

OBJECTIVE

Primary teeth severely affected by amelogenesis imperfecta (AI) often show an extensive loss of enamel. Such defects are difficult to restore with resin composites, since neither the correct anatomic form nor the marginal fit can be guaranteed.

METHODS AND MATERIALS

After clinical and scanning electron microscopic examinations were performed on replica models of 5 patients with primary teeth affected by AI, impressions were made without previous preparation by rotary instruments. Composite crowns and veneers were manufactured and luted adhesively using the total bonding technique and low-viscosity resin composite.

RESULTS

The pre-restorative scanning electron microscopic analysis showed that the dentinal tubules were exposed and that the border of the residual enamel was in the process of splitting. The preoperative oral examination had revealed tooth discoloration, masticatory disturbances, hypersensitivity, and speech problems. After placement of the restorations, patients reported improvements in tooth sensitivity, articulation, and mastication.

CONCLUSIONS

A new protocol for restoration of primary teeth with an extensive loss of enamel is offered. It is quick and easy to perform, highly esthetic, and can be applied in children younger than 4 years old.

An overview of tooth discoloration: extrinsic, intrinsic and internalized stains

The causes of tooth discoloration are varied and complex but are usually classified as being either intrinsic, extrinsic or internalized in nature. Dietary chromogens and other external elements deposit on the tooth surface or within the pellicle layer either directly or indirectly to form extrinsic discoloration. Stains within the dentine or intrinsic discoloration often results from systemic or pulpal origin, while internalized stains are the result of extrinsic stains entering the dentine via tooth defects such as cracks on the tooth surface.

Amelogenesis imperfecta and unusual gingival hyperplasia

BACKGROUND

Amelogenesis imperfecta (AI) is a group of hereditary conditions that primarily involves the defective formation and/or calcification of enamel. The association of AI with gingival enlargement-like lesions has also been reported.

METHODS

This paper reports a case of a hypoplastic AI associated with unusual generalized gingival hyperplasia.

RESULTS

Histological aspect of the gingival growth was characterized by a dense connective tissue with a mild mononuclear inflammatory infiltrate, calcified bodies, and islands of odontogenic epithelium.

CONCLUSION

The present case represents a very interesting demonstration of the fact that, although rare, AI may be associated with generalized gingival enlargement.

Endodontic management of an impacted premolar

This report demonstrates a simple endodontic solution to an interdisciplinary case of a patient with multiple gene deficiencies. An adolescent patient presented with an impacted premolar that could not be extracted due to high-risk conditions. A suspicious degree of radiolucency around the crown was clinically diagnosed as dentigerous cyst. The treatment dilemma and implementation are discussed. This case report offers a different treatment option for impacted teeth when significant differential diagnosis of a pericoronal lesion dictates treatment.

Amelogenesis imperfecta: the multidisciplinary approach. A case report

Amelogenesis imperfecta is a hereditary developmental disorder of the dental enamel, in both primary and permanent dentition. The main clinical characteristics are extensive loss of tooth tissue, poor esthetics, and tooth sensitivity. Transmission of the gene takes place by either autosomal, dominant X-linked, or recessive modes. This clinical report describes a treatment sequence based on a multidisciplinary approach. A 21-year-old girl with hypoplastic amelogenesis imperfecta was referred to the Ege University School of Dentistry clinic. She was concerned about the poor appearance and sensitivity of her teeth. The patient presented with an anterior open bite, although orthodontic treatment had been completed previously. Periodontal gingivectomy of her posterior teeth followed by endodontic treatment where indicated was proposed. The prosthodontic treatment consisted of metal ceramic fixed partial dentures of precious alloy. At the end of treatment, function and esthetics were improved to a level acceptable to both the patient and the dental team.

Case report: clinical management of hypoplastic amelogenesis imperfecta

BACKGROUND

The fundamental therapeutic problems related to amelogenesis imperfecta treatment are governed by the need to effect primary prevention interventions, reducing the risk of calculus accumulation and caries. There are also aesthetic and functional rehabilitative needs. Clinical management rehabilitation techniques vary depending on the AI type, but usually require restoration of affected teeth. Where orthodontic problems also exist, these should be corrected prior to the final restorative treatment.

CASE REPORT

The use of composite resins in aesthetic restoration of permanent anterior and posterior teeth as affected by hypoplastic AI type is described. This case illustrates a patient who suffered from less attrition than those of the hypomineralized varieties. The therapeutic choice has allowed the correction of vertical dimension without the use of preformed crowns.

Amelogenesis imperfecta and nephrocalcinosis: a new case of this rare syndrome

This article describes a new case of a rare syndrome including enamel agenesis of the primary and permanent dentition, delayed or absent eruption of the permanent dentition, coronal intra-alveolar resorption and gingival enlargement. Renal symptoms include medullary nephrocalcinosis without any apparent cause, and evolution to a renal failure. The early diagnosis provided by the oral symptoms leads to a better renal prognosis. As a consequence, pediatric dentists should be aware of this pathology.

Central odontogenic fibroma-like tumors, hypodontia, and enamel dysplasia: review of the literature and report of a case

A patient with multiple odontogenic fibroma-like tumors in the mandible and enamel dysplasia is presented, bringing the total number of cases reported in the literature to 3. In addition to these manifestations, this case had hypodontia. The absence of associated teeth, the size of the lesions, the lingual expansion, and the green-yellow polarization of collagen with Picrosirius stains supported the neoplastic nature of the central odontogenic fibroma-like tumors in the case presented. Laminated psammomatous deposits distinguished the tumors from the World Health Organization-type central odontogenic fibroma.

Amelogenesis imperfecta with growth hormone deficiency in a 12 year-old boy

Amelogenesis imperfecta (AI) is a diverse group of hereditary disorders that are characterized by a defect in the formation of the tooth enamel and a high degree of clinical diversity. X-linked, autosomal dominant and recessive inheritance have been demonstrated. Growth hormone (GH) has an effect on bone and soft tissue development. Dental and facial abnormalities associated with pituitary dwarfism have been reported, but GH deficiency with AI is very rare. We describe a 12 year-old pre-pubertal boy who was referred to our hospital with teeth deformities and growth retardation. His teeth had brown-yellow pigmented surfaces, and dental examination showed extensive enamel deficiency in his permanent teeth. He also had severe growth retardation; height SDS was -3.6. Laboratory examinations showed reduced GH levels, and he was diagnosed as having idiopathic isolated GH deficiency and AI.

Restoring function and esthetics in a patient with amelogenesis imperfecta: a case report

Amelogenesis imperfecta is a hereditary disorder that affects enamel on primary and permanent teeth. It is a rare dental disease but represents a major restorative challenge for the dentist. A 14-year-old boy presented with sensitive, discolored, and mutilated teeth and a decreased vertical dimension of occlusion. The aim of treatment was to reduce dental sensitivity, to restore esthetics, and to correct the vertical dimension of occlusion. To modify the occlusion, and to protect the dentin from chemical and thermal attacks, nickel-chrome onlays were placed on the molars. To improve the esthetics of the incisors and premolars, resin composite restorations were applied. The patient was regularly recalled during the postoperative period. Radiographic and clinical examinations 10 months posttreatment revealed no evidence of disorders associated with the restored teeth or their supporting structures.

Clinical and radiographic features of a family with autosomal dominant amelogenesis imperfecta with taurodontism

This paper describes the clinical features of a family of four generations with autosomal dominant amelogenesis imperfecta with taurodontism (ADAIT). Considerable variation in phenotype was seen, both between individuals and within the dentition of some individuals. Many of the adults had received extensive dental restorative work. These findings re-enforce previous observations of variable phenotype in this and other forms of the condition and add to the argument for a revision of methods of classification. This history of this large family draws further attention to the restorative demands of this group of dental anomalies and, by their generous co-operation, will prove an invaluable help in the investigation by molecular genetic techniques of this disfiguring condition.

Amelogenesis imperfecta: a case report

A case of amelogenesis imperfecta in a Nigerian is presented. Although the patient had almost full complement of teeth, their structure was physically weak and many of them were discoloured. Many of the teeth had lost their enamel and worn down rapidly causing great sensitivity, pain and aesthetic problems for the patient. The clinical features and management of this case are discussed.

Unusual indelible enamel staining following fixed appliance treatment

Two cases are described of indelible enamel staining following fixed appliance therapy. The acquired pigmentation occurred in patients with an identifiable enamel defect prior to treatment. The interaction of factors to cause the staining is discussed and it's prevention in future cases highlighted. Subsequent restoration of the affected teeth is shown.

Hypomaturation amelogenesis imperfecta: account of a family with an X-linked inheritance pattern

Amelogenesis imperfecta (AI) is a heterogeneous genetic disorder which affects the dental enamel. It can have an autosomal dominant, autosomal recessive or X-linked pattern. The authors describe a case of a family with hypomaturation X-linked AI and discuss the clinical and histopathological aspects of this disorder.

Dental anomalies associated with amelogenesis imperfecta: a radiographic assessment

Amelogenesis imperfecta, a group of hereditary conditions primarily affecting the enamel, has been associated with dental anomalies, including taurodontism, congenitally missing teeth, delayed eruption, crown resorption, and abnormal enamel density. The purpose of this study was to assess the prevalence of these anomalies in an amelogenesis imperfecta population. The study group consisted of members of 9 unrelated families--22 family members with amelogenesis imperfecta and 13 unaffected family members. Panoramic radiographs were evaluated for taurodontism, congenitally missing teeth, delayed tooth eruption, pathologic dental resorption, pulp calcification, and radiographic enamel density. The prevalence of taurodontism was similar in people with amelogenesis imperfecta and normal people; all of the remaining parameters were more commonly observed in people with amelogenesis imperfecta. The radiographic enamel density was quantitatively reduced in teeth affected by amelogenesis imperfecta in comparison with teeth with normal enamel. These findings suggest that some of the features associated with amelogenesis imperfecta result from abnormal enamel formation (eg, decreased enamel density, crown resorption) whereas others may occur as a result of expression of the genetic mutation in cells other than ameloblasts (eg, abnormal eruption, pulp calcification).

Craniofacial features associated with amelogenesis imperfecta

Craniofacial alterations occur with increased frequency in patients with amelogenesis imperfecta (AI). The purpose of this study was to characterize the craniofacial features associated with AI in families from the US. Twenty-seven people with AI and 14 unaffected family members from nine separate kindreds were evaluated. The diagnosis was established by history, clinical, and radiographic examination, and histological and or biochemical analysis of enamel. The kindreds were generally classified as hypoplastic AI (HPAI), hypocalcified AI (HCAI), or hypomaturation AI (HMAI) and then further subclassified based on phenotype and mode of inheritance. Linear and angular cephalometric measures were converted to z-scores using gender/age matched values from the Bolton and Behrent's standards. Statistical analyses included t-tests and ANOVA accepting P < or = 0.05 as significant. The vertical dimension of the lower face was significantly increased (ANSMe; P = 0.001), especially in affected individuals compared with unaffected relatives, in all kindreds with HCAI and HMAI but in only one kindred with autosomal recessive rough AI. Clinically, an anterior open bite (overbite < 0 mm) was observed in 26% of all dentate individuals with AI and none of their unaffected relatives. Skeletal morphology was highly variable depending on the AI type and kindred. While this study shows an association of altered craniofacial morphology with certain AI kindreds, the relationship of the AI genotype to the observed malocclusions remains to be defined.

Management of gingival overgrowth associated with generalized enamel defects in a child

Gingival overgrowth is usually associated with systemic conditions or treatment (e.g. blood dyscrasias, anti-epileptic or immunosuppressive agents). A child is presented, who had enlarged gingiva associated with a generalized enamel defect (amelogenesis imperfecta (AI), hypoplastic type) and document the periodontal and restorative management of this case.

Hypocalcification type amelogenesis imperfecta in permanent dentition in association with heavily worn primary teeth, gingival hyperplasia, hypodontia and impacted teeth

A female patient with hypocalcification type amelogenesis imperfecta in permanent dentition in association with heavily worn primary teeth, gingival hyperplasia, hypodontia and impacted teeth is presented.

Open bite deformity in amelogenesis imperfecta. Part 2: Le Fort I osteotomies and treatment results

Functional conditions, skeletal and dento-alveolar stability and condylar changes in 15 patients with mandibular hypoplasia, anterior open bite (AOB) and amelogenesis imperfecta (AI), who had undergone a Le Fort I osteotomy, were analysed after a mean follow-up of 5 years. Two patients underwent a one-piece Le Fort I intrusion osteotomy and 13 patients a multi-segment Le Fort I osteotomy. In three of these patients, an additional bilateral sagittal split osteotomy was performed. Thirteen patients underwent a genioplasty. Surgery was followed by prosthetic rehabilitation in 10 patients. Skeletal and dento-alveolar stability were analysed on lateral cephalometric radiographs and condylar changes on orthopantomographic radiographs. Transverse stability of the dental arches was analysed on dental casts. The treatment results in this group were compared with patients with similar skeletal features but without amelogenesis imperfecta. The harmony of the long faces was restored and a reasonable vertical stability of the maxilla was achieved, however, a slight open bite and tongue interposition was still present. The transverse stability of dental arches (60%) was disappointing. Rigid internal fixation produced better transverse stability. Progressive condylar resorption was seen in two patients (13%). Less occlusal stability could be achieved in patients with AI, but resulted neither in less skeletal stability nor in more susceptibility to morphological condylar changes.

Open bite deformity in amelogenesis imperfecta. Part 1: An analysis of contributory factors and implications for treatment

Anterior open bite (AOB) is often seen in patients with amelogenesis imperfecta (AI). The skeletal and dental components were analysed in 15 patients with AI and AOB. Measurements on cephalometric radiographs and dental models were compared with those of 130 patients with AOB but without enamel anomalies. Skeletal components in the AI and non-AI group were comparable. The AI group showed omega-shaped dental arches and a reversed mandibular curve of Spee. Orthodontic treatment options are limited because of the conical form of the teeth, tight contacts in the posterior regions and the condition of enamel resulting in difficulties in bonding brackets. Fixation problems encountered during surgery are discussed. A multidisciplinary treatment is outlined consisting of a multi-segment Le Fort I osteotomy followed by prosthetic rehabilitation to stabilize occlusion for at least one year postoperatively.

Congenital hypodontia of maxillary lateral incisors in association with coloboma of the iris and hypomaturation type of amelogenesis imperfecta in a large kindred

The dental, clinical, genetic, radiological and dermatoglyphic findings in patients from a large kindred with congenital hypodontia of maxillary lateral incisors (CHMLI) in association with coloboma of the iris (Cl) and hypomaturation type of amelogenesis imperfecta (HTAI) are presented. The pedigree of the kindred showing multiple consanguinaeous marriages and the findings of the family members with CHMLI and a family member with CHMLI, Cl and HTAI and two members with both CHMLI and HTAI suggested that the isolated CHMLI was due to an autosomal recessive gene, but, the Cl was determined by an autosomal dominant gene linked to CHMLI gene. HTAI was an autosomal recessive character linked to both CHMLI and Cl.

Root canal treatment as a treatment modality for temporary tooth retention in adolescent patients

In certain cases root canal treatment may be an adequate intermediate therapy, mainly for severely traumatized teeth in adolescent patients that probably cannot be retained permanently. The treatment aims at temporary retention of otherwise hopeless teeth until definite treatment, for example insertion of bridges or dental implants, may be performed. This kind of treatment can help to avoid the application of removable prostheses in young patients. This treatment modality requires intensive information to be presented to the patients and their parents on the benefits and risks of the treatment procedures, endodontic treatment under aseptic conditions respecting the general guidelines for root canal treatment, and a strict recall regimen to avoid occurrence or increase of pathological conditions. Four cases (five teeth) of temporary tooth retention by endodontic treatment are presented.

Oral rehabilitation of a patient with amelogenesis imperfecta

A patient with Type I hypoplastic patterned amelogenesis imperfecta, subtype D, presented for prosthodontic evaluation. This article describes the developmental and pathophysiological background of this disease. A clinical report describing the diagnosis, treatment planning, and dental rehabilitation of the patient is reviewed.

Restoring function and esthetics in a patient with amelogenesis imperfecta

Amelogenesis imperfecta is a rare dental disease and presents a major challenge to the dentist. With the tremendous advances in the field of esthetic dentistry, especially in bonding to dentin, it is today possible to restore function and esthetics to an acceptable level. The need for full crown preparation has been decreased to an absolute minimum. A case of amelogenesis imperfecta, complicated by a malocclusion, is presented. A combination of periodontal treatment and resin-bonded porcelain onlays and nobel alloys resulted in a highly successful outcome. The virtual absence of enamel was overcome with the aid of dentin bonding.

Supraoccluding cobalt-chrome onlays in the management of amelogenesis imperfecta in children: a 2-year case report

Children suffering from the inherited dental anomaly amelogenesis imperfecta frequently present with sensitive, discolored teeth and decreased lower facial height. The aim of treatment is to reduce sensitivity while maintaining the maximum amount of hard tissue possible until the patient reaches an age at which advanced restorative techniques can be used to rehabilitate the dentition. A case is presented in which amelogenesis imperfecta in the mixed dentition was managed by the placement of adhesive cast restorations. These restorations have been in place for 2 years.

[Incidence of structural disorders of teeth in hereditary epidermolysis bullosa]

Authors present a 12-year old boy, whose diagnosis was epidermolysis bullosa. Beside the general characteristics of the illness they discuss the dental status of the patient and sum up the literary references together with other anomalies occurring in epidermolysis bullosa hereditaria.

Dental development in amelogenesis imperfecta: a controlled study

The present investigation studied dental development in 23 subjects with amelogenesis imperfecta (AI), aged 4.2 to 15.6 years, compared with 46 race-, age-, and sex-matched, healthy, normal controls. The dental ages of the children were assessed from panoramic radiographs using previously established methods. Their chronologic ages at the time of radiographic examination were compared with their dental ages. The results showed that all subjects with AI showed a significant acceleration of dental age of approximately 1.13 +/- 0.78 years compared with control children (P < 0.001). All children were consistently affected regardless of the AI variant. Furthermore, the study found a six-fold increase (26.1 vs. 4.3%) in tendency of AI patients to show impaction of the permanent teeth and associated anomalies such as follicular cysts. These results may be important in planning orthodontic treatment in AI patients, and indicate that they should have early screening to detect these abnormalities.

Craniofacial structure related to inheritance pattern in amelogenesis imperfecta

The aim of this study was to investigate the craniofacial structure in 66 children and adolescents, 34 girls and 32 boys, with known clinical manifestations and inheritance patterns for amelogenesis imperfecta (AI), and to compare the results with those obtained in a control group of age and sex matched persons with normal occlusion. The ages ranged from 6.8 to 21.2 years. Clinically, AI was divided into cases characterized by either hypoplasia or hypomineralization of the enamel. In a further subgrouping, eight clinical variants were diagnosed. Measurements of 12 angular and 15 linear, parameters on lateral cephalometric radiographs were included in comparisons between the AI and the control group. Compared with the control group, the AI group displayed statistically significant differences indicating a skeletal open bite. In the analysis of inheritance patterns and clinical manifestations, a skeletal open bite was associated with autosomal dominant (AD) and X-linked inheritance, and in the AD group with hypomineralization. When all cases except those with X-linked inheritance were pooled, deviations indicating a skeletal open bite were found in the subgroups "rough hypoplastic AI" and "hypomineralization AI." Since a skeletal open bite was found both with X-linked inheritance and in some of the subgroups connected with autosomal inheritance, the hypothesis of a pleiotropic gene effect as the cause of the simultaneous occurrence can be ruled out. The influence of modifying genes or environmental factors is suggested.