Open Access
Educational Article
Issue
J Oral Med Oral Surg
Volume 27, Number 2, 2021
Article Number 21
Number of page(s) 9
DOI https://doi.org/10.1051/mbcb/2020060
Published online 15 January 2021

© The authors, 2021

Licence Creative CommonsThis is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Introduction

Williams–Beuren syndrome [WBS] is a rare, congenital, panethnic, multisystem disorder, that is a result of genetic alterations on chromosome 7q11.23 [1]. The disorder is alternatively known as Williams syndrome, Elfin facies syndrome, chromosome 7q11.23 deletion syndrome [2]. Characteristic features of WBS are the developmental, physical and mental abnormalities associated with it.

WBS was first described in 1961 Dr John Williams, a cardiologist, who reported four children with similar facies, supravalvar aortic stenosis, cognitive impairment, learning difficulties and love for music [3]. Strabismus, pulmonary artery stenosis and tooth abnormalities were added as characteristics of the syndrome in 1962 by Dr Beuren [3]. Online Mendelian Inheritance in Man database has assigned a number #194050 to WBS.

The inheritance pattern of WBS is recognized to be of autosomal dominant type [1]. WBS mainly occurs sporadically, with incidence ranging from 1:20 000 to 1:50 000 [3]. There is no gender dominance in inheritance and the disorder is reported in all ethnicities around the world [3].

The learning objectives of this article include the development of the ability of the oral healthcare student or professional to identify a patient with WBS, diagnose the case, and plan a comprehensive oral health care regimen for the patient. Multidisciplinary consultations and referrals can then be made depending upon each case.

Aetiopathology

The first report on the aetiology of WBS proposed Vitamin D teratogenicity as the likely cause. This presumption was made on the basis of experiments on rabbit foetuses which showed supravalvar aortic stenosis and craniofacial abnormalities upon being exposed to high doses of vitamin D [1]. However, two findings subsequently proved that WBS was genetic, not teratogenic. These two findings were (1) parent to child transmission and (2) discovery of phenotypically overlapping autosomal dominant familial supravalvar aortic stenosis syndrome (OMIM number, 185500) [1].

It is now accepted that WBS is a micro-deletion disorder, caused by deletion/loss of a segment of DNA referred to as the WBS critical interval. This interval on chromosome 7q11.23 extends from 1.5 to 1.8 million base pairs, containing 26–28 genes [4]. Therefore, WBS patients carry only a single copy of these 26–28 genes, in contrast to unaffected individuals who carry two copies of each of these genes [4]. Deletion of the WBS critical interval brings about the spectrum of features that characterise WBS. The size of the deletion is similar across all WBS patients, although considerable variability in the extent of physical and mental abnormalities. This aspect of WBS is derived from the fact that ‘duplicons’ or repetitive DNA segments, crowd around the WBS interval, thereby exposing the chromosome 7 pair to mispairing during meiosis [4]. This suggests that WBS arises from the nature of the genetic material on chromosome 7q11.23 and is not influenced by extrinsic factors such as parental influence or environmental exposures.

The deletion of a copy of the elastin gene [ELN] is thought to be the primary factor responsible for the development of cardiovascular features and certain musculoskeletal features of WBS [4]. The autosomal dominant inheritance pattern implies that affected individuals may have a 50% chance of producing WBS children. Healthy parents with a WBS child have a low risk of recurrence. However, somatic cell mosaicism remains a relative possibility [5].

Clinical features

WBS includes a myriad of physical, developmental and neuro cognitive disorders. These features are listed in (Tab. I) [69]. If supravalvar aortic stenosis [SVAS, moderate to severe form] is left untreated, it may progress to left ventricular hypertrophy or heart failure [7]. SVAS is also associated with risk of sudden death in WBS patients, a likely outcome of compromised coronary perfusion [7]. Sudden death can also occur under general anaesthesia, as a result of decreased coronary artery perfusion pressure [7]. In contrast, pulmonary artery stenosis [PAS] often regresses and resolves over time in WBS.

Pectus excavatum denotes a sunken or caved-in chest, usually a result of deformity of the rib cage and sternum, leading to a structural alteration of the anterior thoracic wall [6]. Chiari malformation type I refers to a condition in which a small or deformed skull causes the brain (cerebellum) to be displaced into the upper spinal canal [9]. Kyphoscoliosis denotes a spinal deformity in which the spine is abnormally curved, both in the coronal and saggital planes [9]. A hallus valgus deformity results in painful disability and denotes the malpositioning of the first metatarsophalangeal joint as a result of lateral deviation of the great toe with a medial deviation of the first metatarsal bone [9]. Paralysis of the vocal chords may bring about a rough or coarse voice in WBS individuals [6].

The orofacial features characteristic of WBS are listed in (Tab. II) [5,6,1013] and illustrated in (Fig. 1). Mass and Belostoky [10], in 1993, described four skeletal features as characteristic of the facial features of children with WBS: shortened anterior skull base, steep mandibular plane angle, disproportionate upper-to-lower anterior facial height and posterior-to-anterior facial height, although overall facial height is unaffected, and a deficient albeit non-retrognathic chin [11]. The dysmorphic facial features in WBS syndrome are typically known as “elfin facies” [12]. Maritsi et al. reported a case of benign paroxysmal torticollis (BPT) in a 14 month old with WBS [14]. Cingano et al. observed that in younger patients, poor oral hygiene measures brought about by a combination of factors such as lack of co-operation from patients, malocclusion and tooth agenesis resulted in a higher prevalence of gingival and periodontal diseases [15]. Furthermore, the authors stressed on the absence of the gene located on chromosome 7 in these patients which regulates the formation of elastin. Absence or significant alteration of elastin in the connective tissue of the gingiva and periodontal ligament predisposes these tissues to damage from plaque microbes [15].

WBS is not usually associated with malignancy. However, two types of malignant tumours have been reported in WBS patients, namely lymphomas (2 cases of Burkitt lymphoma,one case of non-Hodgkin lymphoma and one of T cell lymphoblastic lymphoma) and gliomas (one case of astrocytoglioma and one case of anaplastic oligodendroglioma) [16]. WBS patients must therefore be investigated for presence of such tumours, especially when neurological symptoms fall outside those commonly noted with the disorder.

Table I

Clinical features of Williams–Beuren syndrome.

Table II

Orofacial features of Williams–Beuren syndrome.

thumbnail Fig. 1

Facial and dental features of WBS. (A and B) Skeletal class II malocclusion, mandibular retrognathism, dental biprotrusion, thick lips. (C) deep bite, overjet, screwdriver shaped incisors and diastema. (D and E) thick lips, and small chin. (F) cross-bite, dental biprotrusion, and diastemas. (G and H) front and lateral pictures showing wide mouth, midface flattening. (Reprinted from Castro T, de Paula Martins Santos C, de Oliveira Lira Ortega A, Gallottini M. Oral characteristics and medical considerations in the dental treatment of individuals with Williams syndrome. Special Care in Dentistry. 2019 Mar; 39(2):108–13. DOI: https://doi.org/10.1111/scd.12361, with permission.)

Diagnosis

According to the American Academy of Pediatrics (APP) [Committee on Genetics, 2001], the clinical diagnostic criteria for WBS is based on 7 groups of findings, each with specific scoring [17]. These findings are growth disturbances (1 point), behavior and development (1 point), dysmorphic facial features (3 points), echocardiographic disturbances evident of SVAS or peripheral pulmonary artery stenosis (5 points) and other cardiovascular disorders (1 point), connective tissue disorders (2 points), and serum calcium assessment (2 points). If the total score is <3, then clinical diagnosis of WBS is unlikely and if ≥3, further investigations for WBS with genetic testing are recommended.

However, clinical presentation of WBS can be varied, courtesy of the atypical copy number variations (CNVs) associated with the chromosome region. In some instances, Noonan syndrome and Turner syndrome present with symptoms that may be identical to those of WBS, thus creating a diagnostic dilemma [18].

Genetic testing methods involve determination of the copy number of sequences on chromosome 7 and may include targeted deletion analysis by fluorescence in situ hybridization (FISH) technique [19]. Although the American College of Medical Genetics and Genomics (ACMG) recommends FISH as the primary diagnostic test for WBS, it is not ideal for the study of copy number variations (CNVs) [20]. Recently, two techniques namely Chromosomal microarray analysis (CMA) and Multiplex ligation dependent probe amplification (MLPA) have been successfully applied to detect the CNVs in the 7q11.23 regions [21].

General health management

The American Academy of Pediatrics Committee on Genetics, has laid down specific criteria for the healthcare supervision of children with confirmed WBS [22]. These guidelines are age-specific and assist the pediatrician in providing adequate care and guidance to the child through his/her developmental years through to adulthood. Table III presents the guidelines [22].

Special considerations for the WBS child must include: avoiding multivitamin preparations owing to possible untoward effects of vitamin D on serum calcium [22], minimizing endogenous production of vitamin D by the appropriate use of sunscreen lotions, periodic cardiovascular evaluations notwithstanding normal baseline findings, hypertension screening periodically, and establishment of a medical home with active participation of caregivers as partners in continual healthcare management [22]. When hypercalcemia is observed, a pediatric dietician/nutritionist must be consulted to implement and monitor dietary calcium restriction. A pediatric urologist referral should be considered. In case hypercalciuria is observed, repeated urine calcium-creatinine ratio (morning and afternoon) monitoring must be undertaken. In case of continual elevation, serum calcium is rechecked and renal ultrasonography is ordered for nephrocalcinosis [22].

Table III

Guidelines for healthcare supervision of children through adulthood with WBS.

Oral healthcare management

The cardiovascular disorders in WBS may be serious enough to place the patient's life at risk when dental treatment is rendered, either under local or general anaesthesia [18]. It is therefore imperative that the oral health care provider consults a pediatric cardiologist for possible antibiotic prophylaxis and other strategies to minimize the inherent risks (Table IV). Congenital heart defects account for 53–80% of individuals with WBS [5]. Antibiotic prophylaxis regime in such patients is 2 g or 50 mg/kg of amoxycillin orally, given 30 minutes to 1 hour prior to invasive procedures, according to the guidelines laid down by the American Heart Association and American College of Cardiology [23]. For those unable to take oral medication, ampicillin 2 g or 50 mg/kg orcefazolin/ceftriaxone 1 g or 50 mg/kg is administered IM/IV. Patients allergic to penicillins or ampicillin can be administred oral cephalexin 2 g or 50 mg/kg, clindamycin 600 mg or 20 mg/kg, azithromycin/ clarithromycin 500 mg or 15 mg/kg. If patient is allergic to penicillins or ampicillin and unable to take oral medication, cefazolin/ceftriaxone 1 g or 50 mg/kg IM/IV or clindamycin 600 mg or 20 mg/kg IM/IV can be administered [24].

The great vessels of the heart constrict before the age of 5 years in WBS childrenand cardiac disease severity worsens with progressive age [5]. Therefore, before any dental intervention, cardiac status must be reviewed. Intravenous catheterization under general anesthesia has lead to myocardial infraction or cardiac arrest in infants [25]. Furthermore, significant morbidity and early (sudden) death in children in majority of cases is attributed to cardiac abnormalities such as arterial narrowing (stenosis), hypoplasia or coarctation [5].

Considering the cardiac risk factors, the fact that dental treatment may incite anxiety in WBS patients [5], mental retardation and tendency towards uncooperative behavior in the dental office, it will be prudent to think that dental treatment may preferably be provided under conscious sedation or general anesthesia in a hospital setting. However, there is no contraindication to routine dental treatment in the dental office, under local anesthesia, in cooperative patients with mild cardiac/systemic abnormalities. Collins et al. proposed a risk stratification system for anesthetic administration in WBS patients [26]. Table V presents this stratification system. Furthermore, cardiac evaluation and general anesthesia must be performed by experienced specialist pediatric cardiologists/anesthesiologists.

A high dental caries prevalence is observed in WBS individuals owing to hypercalcemia-induced enamel hypoplasia and hypomineralization, with concomitant delayed tooth eruption [18]. Anorexia and vomiting are other risk factors reported to be responsible for enhanced caries vulnerability [27]. Prevention of infection in the oral cavity is the best way to minimize dental problems, especially in vulnerable WBS individuals such as those with severe enamel hypoplasia, high dental caries incidence and severe cardiac conditions [18]. Intense preventive and dietary counseling must be organized for such individuals, particularly children. Fluoride mouthwash, topical fluoride applications, tooth brushing twice a day, oral water rinse after every feed, use of a dental floss once every night, regular quarterly professional prophylaxis, and pit and fissure sealants are some of the preventive measures. Use of a powered toothbrush may be indicated for those with mental disabilities or those who have tooth brushing performed by caregivers [28].

Most WBS children exhibit varying degrees of anxiety and uncooperative behavior in the dental office. Behavior modification can be brought about through modulating sessions that use the basic behavior guidance techniques recommended by the American Academy of Paediatric Dentistry (AAPD) guidelines on behavior guidance for pediatric dental patients [29]. These guidelines recommend methods such as efficient communication with and communication guidance for the patient, tell-show-do technique, appropriate use of voice control, non verbal communication, use of positive reinforcement, distracting the patient, parental presence/absence and nitrous oxide/oxygen inhalation sedation to modulate child behavior positively and to gain cooperation for dental treatment [29].

Visual acuity may be affected to varying degrees in WBS patients. Inability to visualize the surroundings and operative equipment may increase the patients' anxiety, apprehension and fear of the unknown [30]. Patients may be allowed to have tactile stimulation by touching operative instruments, the dental chair, and take a tour of the dental office to acclimatize themselves to the surroundings since they have a better chance to overcome apprehension and fear of the unknown, at the same time forging a strong bond with the support staff at the dental office [18].

WBS patients exhibit a strong affinity towards music. This fact can be utilized to advantage at the dental office to gain cooperation from patients and assist in keeping them more relaxed during treatment, especially considering the hyperacusis associated with WBS patients. Allowing patients to use their headphones and listen to their choice of music is preferable in WBS patients. Furthermore, hyperacusis predisposes WBS patients to easy distraction during dental procedures making them vulnerable to mishaps from sudden involuntary movements while in the dental chair [31]. The dental chair operating light may be disturbing to WBS patients owing to photophobia and allowing them to wear a pair of sunglasses may assist in mitigating this issue [18].

Benefits of early dental evaluation and parental education cannot be understated in WBS patients, considering that dental caries and pulpal infection may increase the risk of serious complications due to congenital heart defects and the inherent risk of subacute bacterial endocarditis (SABE) [18]. A comprehensive radiographic examination must be undertaken to evaluate any dental anomalies and establish a treatment plan for restorative and orthodontic rehabilitation of patients [18].

Yamaguchi et al. have reported the treatment of a 4 year old WBS patient with isolated cleft palate who was followed up of 20 years [32]. They successfully completed non invasive procedures such as orthodontic treatment, invasive procedures such as maxillary anterior segmental distraction osteogenesis and dental implant supported prosthetic rehabilitation. They highlighted the fact that in WBS patients with minimal systemic compromise, acceptable mental abilities and cooperative behavior, oral healthcare provision could be carried out without untoward incidents. Orthodontic evaluation and treatment is advisable in WBS children as soon as their behavior allows cooperation. Primary and mixed dentition stages are preferable for eradication of mucogingival problems associated with anterior cross-bite and pseudo class III malocclusion [18].

Important information to remember in WBS patients is that they have an increased chance of developing impaired glucose tolerance with reduced insulin sensitivity, eventually progressing to type 2 diabetes mellitus [33]. Therefore, it would be prudent to recheck their glycemic levels before every dental appointment when spaced a few months to a year apart [34]. Urban et al. demonstrated with the use of electron microscopy, that elastin gene deletion in WBS resulted in reduced elastin fibre deposition and accumulation of abnormal elastin fibres in the skin [35]. This compromised the mechanical properties of the skin. It would be prudent to think that all facial incisions used to access jaw fractures such as condylar fractures may be avoided and treatment be completed by conservative methods such as maxillo-mandibular fixation. Similarly, it would be wise to avoid raising mucoperiosteal flaps in the oral cavity such as are used in third molar surgery, endodontic surgery and periodontal flap surgeries. The risk of wound dehiscence is greater in WBS patients.

The proceedings at the 15th professional conference on Williams Syndrome, 2016, provided guidelines for selection of the type of anesthesia for dental procedures [36]. The panel suggested that, since a private dentist's office would generally be unable to appropriately monitor patients during and after sedation (ECG, oxygen saturation), for procedures under conscious sedation, dental procedures (especially in WBS children) are best performed at a center with specialized expertise in anesthesia [36]. Therefore, low cardiac risk individuals (Tab. IV, Collins et al. [26]) are the only WBS subset of individuals who can safely be treated under local and/or behavioral treatment at the dental office. Adrenaline must not be used with local anesthesia in WBS patients [36]. Accordingly, mild risk individuals requiring sedation and moderate/high risk individuals are treated in a hospital setting only.

Presence of significant renal compromise may complicate oral healthcare in WBS patients. Constant blood pressure monitoring is advisable in light of the fact that hypertension is a risk factor for cardiac complications. Nephrotoxic drugs such as aminoglycosides and tetracyclines must be avoided [37]. Penicillins, cephalosporins and clindamycin are safe antibiotic choices. Paracetamol is the best drug for pain relief, although severe pain can be managed with codeine, even in an unmodified dose [37]. Aspirin and NSAIDs ate contraindicated in WBS patients with significant renal disease since they increase bleeding tendency and may contribute to deterioration of renal function [37]. If patients are on hemodialysis, dental procedures must be planned on the day following the dialysis. Local anesthetics may be safely used since they are eliminated from the hepatic route [37].

Renal disease also predisposes the WBS patient to bleeding tendencies due to anemia and platelet aggregation disorders [37]. Some WBS patients may also be on oral anticoagulants due to cardiac issues. International normalized ratio (INR) and a blood hemogram with coagulation time testing would be mandatory before any invasive procedure. Local hemostatic measures such as digital compression, cold applications, tranexamic acid mouthwash, cellulose sponges and sutures are generally sufficient to arrest local haemorrhage in patients with INR ≤2 [37]. In patients with INR >2, a nephrologist consultation to reduce the level to below 2 must be undertaken to plan dental procedures.

Table IV

Risk factors for oral healthcare and specific treatement modifications required.

Table V

Risk stratification for WBS undergoing procedures under general anesthesia.

Conclusion

Considering the significant impediments to oral healthcare provision in WBS patients, prevention of oral infection seems to be the best strategy. Dietary counselling, periodic oral examinations, oral prophylaxis, and early recognition and treatment of dental problems can mitigate serious complications and risks involved in treating advanced oral infections in WBS patients. The choice of local anesthetia/sedation/general anesthesia for carrying out dental procedures in WBS individuals must be made considering the needs of the procedure, as well as the physiologic/mental abilities of the patient. A coordinated, multidisciplinary approach to oral healthcare could provide the patient with a healthy oral cavity, in a safe environment, which in turn would mean a healthier patient.

Conflict of interest

None declared.

Funding source

Self funded.

IRB approval

Not applicable.

References

  1. Pober BR. Williams-Beuren syndrome. N Engl J Med. 2010;362:239–52. [Google Scholar]
  2. Online Mendelian Inheritance in Man. #194050. Johns Hopkins University. Available from https://www.omim.org/entry/194050 (accessed on 27 May 2020). [Google Scholar]
  3. Castro T, de Paula Martins Santos C, de Oliveira Lira Ortega A, Gallottini M. Oral characteristics and medical considerations in the dental treatment of individuals with Williams syndrome. Spec Care Dentist. 2019;39:108–113. [Google Scholar]
  4. Shin J, Lee J. Considerations for dental treatment of Williams syndrome patients. J Korean Acad Oral Health. 2018;42:238–241. [Google Scholar]
  5. Moskovitz M, Brener D, Faibis S, Peretz B. Medical considerations in dental treatment of children with Williams syndrome. Oral Surg Oral Med Oral Pathol Oral Radiol Endodontol. 2005;99:573–580. [Google Scholar]
  6. Online Mendelian Inheritance in Man. #194050. Johns Hopkins University. Available from https://www.omim.org/clinicalSynopsis/194050 (accessed on 27 May 2020). [Google Scholar]
  7. Gray III JC, Krazinski AW, Schoepf UJ, Meinel FG, Pietris NP, Suranyi P, et al. Cardiovascular manifestations of Williams syndrome: imaging findings. Journal of cardiovascular computed tomography. 2013;7:400–407. [Google Scholar]
  8. Sammour ZM, Gomes CM, de Bessa Jr J, Pinheiro MS, Kim CA, Hisano M, et al. Congenital genitourinary abnormalities in children with Williams–Beuren syndrome. J Pediatr Urol. 2014;10:804–809. [Google Scholar]
  9. Copes LE, Pober BR, Terilli CA. Description of common musculoskeletal findings in Williams Syndrome and implications for therapies. Clin Anat. 2016;29:578–589. [Google Scholar]
  10. Mass E, Belostoky L. Craniofacial morphology of children with Williams syndrome. Cleft-Palate Craniofac J. 1993;30:343–349. [Google Scholar]
  11. Dogan OA, Kiper PO, Utine GE, Alikaşifoglu M, Boduroglu K. A diagnosis to consider in an adult patient with facial features and intellectual disability: Williams syndrome. Korean J Fam Med. 2017;38:102. [Google Scholar]
  12. Pereira L, Soares DN, de Lima Pedro R, da Silva Fidalgo TK, Costa MC, de Araújo Castro GF. Orofacial findings and dental management of a child with Williams syndrome. Revista Odonto Cienc. 2016;31:41–44. [Google Scholar]
  13. Torres CP, Valadares G, Martins MI, Borsatto MC, Díaz-Serrano KV, Queiroz AM. Oral findings and dental treatment in a child with Williams–Beuren syndrome. Braz Dent J. 2015;26:312–316. [Google Scholar]
  14. Maritsi D, Kossiva L, Vartzelis G. Williams syndrome with a “twist”. Case Rep Med. 2010;2010:726845. [Google Scholar]
  15. Cingano L, Servetto R, Loria P, Calcagno E. Odontostomatological aspects in patients with Williams syndrome: a series of 4 cases. Minerva Stomatol. 2013;62:447–54. [PubMed] [Google Scholar]
  16. Chonan M, Kanamori M, Kumabe T, Saito R, Tominaga T. Pilomyxoidastrocytoma of the cerebellum with Williams syndrome: a case report. Childs Nerv Syst. 2013;29:1211–1214. [Google Scholar]
  17. Tekendo-Ngongang C, Dahoun S, Nguefack S, Gimelli S, Sloan-Béna F, Wonkam A. Challenges in clinical diagnosis of Williams-Beuren syndrome in sub-Saharan Africans: case reports from Cameroon. Mol Syndromol. 2014;5:287–292. [Google Scholar]
  18. Campos-Lara P, Santos-Diaz MA, Ruiz-Rodríguez MS, Garrocho-Rangel JA, Pozos-Guillén AJ. Orofacial findings and dental management of Williams-Beuren syndrome. J Clin Pediatr Dent. 2012;36:401–404. [Google Scholar]
  19. Morris CA. Williams Syndrome. 1999 Apr 9 [Updated 2017 Mar 23]. In: Adam MP, Ardinger HH, Pagon RA, et al. (editors). GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993–2020. Available from https://www.ncbi.nlm.nih.gov/books/NBK1249/ [Google Scholar]
  20. Manning M, Professional HL. Practice and Guidelines Committee. Array-based technology and recommendations for utilization in medical genetics practice for detection of chromosomal abnormalities. Genet Med. 2010;12:742–745. [Google Scholar]
  21. Xia Y, Huang S, Wu Y, Yang Y, Chen S, Li P, Zhuang J. Clinical application of chromosomal microarray analysis for the diagnosis of Williams–Beuren syndrome in Chinese Han patients. Mol Genet Genom Med. 2019;7:e00517. [Google Scholar]
  22. Committee on Genetics. Health care supervision for children with Williams syndrome. Pediatrics. 2001;107:1192–1204. [PubMed] [Google Scholar]
  23. Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP 3rd, Fleisher LA, et al. AHA/ACC Focused Update of the2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease: a Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation 2017;135:e1159-e1195. [Google Scholar]
  24. ADA. Antibiotic prophylaxis prior to dental procedures. Oral Health Topics 2017 [cited 31st March 2017]; Available from http://www.ada.org/en/member-center/oral-health-topics/antibiotic-prophylaxis [Google Scholar]
  25. Bird LM, Billman GF, Lacro RV, Spicer RL, Jariwala LK, Hoyme HE, et al. Sudden death in Williams syndrome: report of ten cases. J Pediatr. 1996;129:926–931. [Google Scholar]
  26. Collins II RT, Collins MG, Schmitz ML, Hamrick JT. Peri-procedural risk stratification and management of patients with Williams syndrome. Congenit Heart Dis. 2017;12:133–142. [Google Scholar]
  27. Lourenço M, Azevedo A, Brandao I, Petit C, Jung S, Huck O. Orofacial manifestations in outpatients with anorexia nervosa and bulimia nervosa focusing on the vomiting behavior. Clin Oral Invest. 2018;22:1915–1922. [Google Scholar]
  28. Waldron C, MacGiolla Phadraig C, Nunn J, Comiskey C, Swift DE, Guerin S, et al. Oral hygiene programmes for people with intellectual disabilities. Cochrane Database Syst Rev. 2017;2017:CD012628. [Google Scholar]
  29. American Academy on Pediatric Dentistry Clinical Affairs Committee Behavior Management Subcommittee; American Academy on Pediatric Dentistry Council on Clinical Affairs. Guideline on behavior guidance for the pediatric dental patient. Pediatr Dent. 2011-2012;33:161–173. [Google Scholar]
  30. Royston R, Howlin P, Waite J, Oliver C. Anxiety disorders in Williams syndrome contrasted with intellectual disability and the general population: a systematic review and meta-analysis. J Autism Dev Disord. 2017;47:3765–3777. [Google Scholar]
  31. Poornima P, Patil PS, Subbareddy VV, Arora G. Dentofacial characteristics in William's syndrome. Contemp Clin Dent. 2012;3:S41. [Google Scholar]
  32. Yamaguchi T, Shirota T, Adel M, Takahashi M, Haga S, Nagahama R, et al. Orthodontic treatment and maxillary anterior segmental distraction osteogenesis of a subject with Williams–Beuren Syndrome and isolated cleft palate: a long-term follow-up from the age of 5 to 24 years. Case Rep Dent. 2017;2010:7019045. [Google Scholar]
  33. Axelsson S, Bjørnland T, Kjaer I, Heiberg A, Storhaug K. Dental characteristics in Williams syndrome: a clinical and radiographic evaluation. Acta Odontol Scand. 2003;61:129–136. [Google Scholar]
  34. Wong D, Ramachandra SS, Singh AK. Dental management of patient with Williams syndrome − a case report. Contemp Clin Dent. 2015;6:418–420. [Google Scholar]
  35. Urban Z, Peyrol S, Plauchu H, Zabot MT, Lebwohl M, Schilling K, et al. Elastin gene deletions in Williams syndrome patients result in altered deposition of elastic fibers in skin and a subclinical dermal phenotype. Pediatr Dermatol. 2000;17:12–20. [Google Scholar]
  36. Walton JR, Martens MA, Pober BR. The proceedings of the 15th professional conference on Williams Syndrome. Am J Med Genet A. 2017;173:1159–1171. [Google Scholar]
  37. Costantinides F, Castronovo G, Vettori E, Frattini C, Artero ML, Bevilacqua L, et al. Dental care for patients with end-stage renal disease and undergoing hemodialysis. Int J Dent. 2018;2018:9610892. [Google Scholar]

All Tables

Table I

Clinical features of Williams–Beuren syndrome.

Table II

Orofacial features of Williams–Beuren syndrome.

Table III

Guidelines for healthcare supervision of children through adulthood with WBS.

Table IV

Risk factors for oral healthcare and specific treatement modifications required.

Table V

Risk stratification for WBS undergoing procedures under general anesthesia.

All Figures

thumbnail Fig. 1

Facial and dental features of WBS. (A and B) Skeletal class II malocclusion, mandibular retrognathism, dental biprotrusion, thick lips. (C) deep bite, overjet, screwdriver shaped incisors and diastema. (D and E) thick lips, and small chin. (F) cross-bite, dental biprotrusion, and diastemas. (G and H) front and lateral pictures showing wide mouth, midface flattening. (Reprinted from Castro T, de Paula Martins Santos C, de Oliveira Lira Ortega A, Gallottini M. Oral characteristics and medical considerations in the dental treatment of individuals with Williams syndrome. Special Care in Dentistry. 2019 Mar; 39(2):108–13. DOI: https://doi.org/10.1111/scd.12361, with permission.)

In the text

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.