Dental and craniofacial characteristics in a patient with leprechaunism treated with insulin-like growth factor-I

Strategic treatment planning for anterior open bite: A comprehensive approach

Anterior open bite (AOB), characterized by the lack of vertical overlap between upper and lower anterior teeth, poses a considerable challenge in orthodontics. The condition depends on many factors that combine to render it difficult to achieve post treatment stability. AOB is commonly classified as dental, skeletal, or functional on the basis of the clinical presentation and causative factors. Traditionally, skeletal AOB necessitates surgical intervention, whereas nonsurgical approaches such as extrusion arches and the Multiloop Edgewise Archwire Technique (MEAW) can be employed in more straightforward cases. Functional appliances are reserved for situations in which a patient's growth potential offers the possibility of effectively addressing AOB. This review presents a strategic treatment approach for addressing AOB, taking into account the classification and severity of the condition. The proposed SHE framework describes the use of mini-screws (S) for anchorage and vertical control, encouragement to correct habits (H), and the utilization of extractions and elastics (E). By incorporating extra-radicular mini-screws, AOB closure is achieved through anterior retraction in extraction cases or whole arch distalization of dentition with elastics in non-extraction cases. This framework emphasizes habit correction through a regimen of oral myofunctional therapy (OMT) and habit-correcting appliances to enhance posttreatment stability. This review suggests that nonsurgical correction is viable in the majority of cases, whereas surgical intervention should be reserved for severe cases of skeletal vertical overgrowth or horizontal discrepancies.

Severe insulin resistance syndrome - A rare case report and review of literature

Insulin Resistance syndromes (IR's), are a group of genetic disorders caused due a functional defect in chromosome 19p13. It is an autosomal recessive condition. Donohue Syndrome was initially described by Donohue and Uchida in 1948 and 1954, a case of sisters born to parents with a first-degree consanguineous marriage. Infants presented with typical facial features that resembled the Leprechaun elves of Irish fairy tales. The following is a report of a rare case of dental complications of Severe Insulin Resistance Syndrome. An eight year old female child, with characteristic features of severe insulin resistance syndrome, reported to the Department of Pediatric and Preventive Dentistry, Pravara Institute of Medical Sciences, Loni, presenting with cariously destructed molars and a previous history of dental treatment under local anaesthesia. Given her condition, it was decided to reduce the multiple appointments, to one appointment with all procedures done under general anaesthesia. The following case report discusses the advantages, disadvantages and post operative complications faced when forming a treatment strategy for Severe Insulin Resistance Syndrome.

Clinical characteristics of insulin resistance syndromes: A nationwide survey in Japan

AIMS/INTRODUCTION

Insulin resistance syndrome (IRS) of type A or B is triggered by gene abnormalities of or autoantibodies to the insulin receptor, respectively. Rabson-Mendenhall/Donohue syndrome is also caused by defects of the insulin receptor gene (INSR), but is more serious than type A IRS. Here, we carried out a nationwide survey of these syndromes in Japan.

MATERIALS AND METHODS

We sent questionnaires to a total of 1,957 academic councilors or responsible individuals at certified facilities of the Japan Diabetes Society, as well as at the department pediatrics or neonatology in medical centers with >300 beds.

RESULTS

We received 904 responses with information on 23, 30 and 10 cases of type A or B IRS and Rabson-Mendenhall/Donohue syndrome, respectively. Eight cases with type A IRS-like clinical features, but without an abnormality of INSR, were tentatively designated type X IRS, with five of these cases testing positive for PIK3R1 mutations. Fasting serum insulin levels at diagnosis (mean ± standard deviation) were 132.0 ± 112.4, 1122.1 ± 3292.5, 2895.5 ± 3181.5 and 145.0 ± 141.4 μU/mL for type A IRS, type B IRS, Rabson-Mendenhall/Donohue syndrome and type X IRS, respectively. Type A and type X IRS, as well as Rabson-Mendenhall/Donohue syndrome were associated with low birthweight. Type B IRS was diagnosed most frequently in older individuals, and was often associated with concurrent autoimmune conditions and hypoglycemia.

CONCLUSIONS

Information yielded by this first nationwide survey should provide epidemiological insight into these rare conditions and inform better healthcare for affected patients.

Insulin-like growth factor 1 modulates bioengineered tooth morphogenesis

Regenerative therapy to replace missing teeth is a critical area of research. Functional bioengineered teeth have been produced by the organ germ method using mouse tooth germ cells. However, these bioengineered teeth are significantly smaller in size and exhibit an abnormal crown shape when compared with natural teeth. The proper sizes and shapes of teeth contribute to their normal function. Therefore, a method is needed to control the morphology of bioengineered teeth. Here, we investigated whether insulin-like growth factor 1 (IGF1) can regulate the sizes and shapes of bioengineered teeth, and assessed underlying mechanisms of such regulation. IGF1 treatment significantly increased the size of bioengineered tooth germs, while preserving normal tooth histology. IGF1-treated bioengineered teeth, which were developed from bioengineered tooth germs in subrenal capsules and jawbones, showed increased sizes and cusp numbers. IGF1 increased the number of fibroblast growth factor (Fgf4)-expressing enamel knots in bioengineered tooth germs and enhanced the proliferation and differentiation of dental epithelial and mesenchymal cells. This study is the first to reveal that IGF1 increases the sizes and cusp numbers of bioengineered teeth via the induction of enamel knot formation, as well as the proliferation and differentiation of dental epithelial and mesenchymal cells.

Mecasermin in Insulin Receptor-Related Severe Insulin Resistance Syndromes: Case Report and Review of the Literature

Mutations in the insulin receptor (INSR) gene underlie rare severe INSR-related insulin resistance syndromes (SIR), including insulin resistance type A, Rabson–Mendenhall syndrome and Donohue syndrome (DS), with DS representing the most severe form of insulin resistance. Treatment of these cases is challenging, with the majority of DS patients dying within the first two years of life. rhIGF-I (mecasermin) has been reported to improve metabolic control and increase lifespan in DS patients. A case report and literature review were completed. We present a case involving a male patient with DS, harbouring a homozygous mutation in the INSR gene (c.591delC). Initial rhIGF-I application via BID (twice daily) injection was unsatisfactory, but continuous subcutaneous rhIGF-I infusion via an insulin pump improved weight development and diabetes control (HbA1c decreased from 10 to 7.6%). However, our patient died at 22 months of age during the course of a respiratory infection in in Libya. Currently available data in the literature comprising more than 30 treated patients worldwide seem to support a trial of rhIGF-I in SIR. rhIGF-I represents a treatment option for challenging SIR cases, but careful consideration of the therapeutic benefits and the burden of the disease is warranted. Continuous application via pump might be advantageous compared to single injections.

Successful rhIGF1 treatment for over 5 years in a patient with severe insulin resistance due to homozygous insulin receptor mutation

BACKGROUND

Congenital insulin resistance syndromes are caused by biallelic mutations within the insulin receptor gene (INSR). Recombinant human insulin-like growth factor (rhIGF1) has been used with mixed success; however, rigorous assessment of its efficacy is lacking. Here, we describe a child with a homozygous mutation in INSR successfully treated with rhIGF1 for more than 5 years.

CASE REPORT

The patient presented with osmotic diabetes symptoms and was noted to have dysplastic dentition, hypertrichosis, coarse and dysmorphic facial features. Acanthosis nigricans, skin tags and rugated hyperkeratosis were also evident on the posterior neck, axilla and groin. A homozygous INSR essential splice site mutation (c.1268 + 2T > C, p.G374 fs*12) was identified, for which both parents were found to be heterozygous. The patient was treated with twice daily injections of rhIGF1 and metformin for more than 5 years with improvement in her acanthosis nigricans, hyperkeratosis and hypertrichosis. A dramatic fall in fasting insulin, HOMA-IR and HbA1c has been maintained over the entire course of treatment without adverse effects. Her linear growth velocity has remained on target for her predicted adult height.

DISCUSSION

Our case demonstrates the effectiveness of rhIGF1 as an early treatment in a patient with a biallelic mutation within INSR without evidence of fluid retention, retinopathy, muscle pain, heart failure, cerebral infarcts or benign intracranial hypertension. Her case suggests rhIGF1 can and should be considered as an initial treatment option instead of as a final option in those with INSR mutations.

Do prenatal and postnatal hypothyroidism affect the craniofacial structure?: An experimental study

OBJECTIVE

To investigate the effect of experimental prenatal and postnatal hypothyroidism (HT) on the craniofacial structure in rats.

MATERIALS AND METHODS

Female Wistar albino rats were mated with males for fertilization. Pregnant rats were divided into three groups. Group 1 (methimazole [MMI]-induced prenatal hypothyroidism group) mother rats were given MMI water during and after pregnancy. Group 2 (MMI-induced postnatal hypothyroidism group) mother rats were given MMI water after pregnancy. After the breast-feeding period, group 1 and 2 rat pups received the same water as their lactating mothers drank. Group 3 (control group) pregnant rats and rat pups were given normal tap water. When the rat pups were 90 days of age, lateral cephalometric and posteroanterior films were taken under anesthesia.

RESULTS

Posteroanterior radiographs revealed that palatal, cranial, bizygomatic arch, and bigonial width measurements were significantly shorter in prenatal HT and postnatal HT groups compared to the control group (P < .001). Intragroup comparisons in lateral cephalometric radiographs showed that, nearly all of the comparisons were statistically significant (P < .05), with the exception of the Co-Gn, E-Pg/S-Gn measurements between the prenatal and postnatal HT groups.

CONCLUSIONS

Sagittal and transverse measurements showed that untreated HT has detrimental effects on the growth of the maxilla and mandible.