Craniofacial and dentoalveolar morphology in individuals with Prader-Willi syndrome: a case-control study.

BACKGROUND: Prader-Willi syndrome (PWS) is a complex multisystem genetic disorder with distinct genetic and clinical features. Among other clinical symptoms, PWS is characterized by severe infantile hypotonia with feeding problems, childhood onset hyperphagia, obesity, scoliosis, short stature combined with growth hormone deficiency and developmental delay. PWS is associated with facial dysmorphology, orofacial dysfunction, oral abnormalities, low salivary flow and subsequent severe tooth wear. Little is known about the craniofacial growth direction or dental and skeletal relationships in individuals with PWS in different ages. The purpose of this study was to assess the craniofacial and dentoalveolar characteristics and to investigate the craniofacial growth direction separately in children, young adults and adults with PWS, using a cephalometric analysis of lateral cephalograms. RESULTS: Lateral cephalograms of 42 individuals with a confirmed genetic diagnosis of PWS were analysed and divided into three groups according to their age: Children (< 12 years), young adults (12-20 years) and adults (> 20 years). Cephalometric variables were compared between PWS patients and controls by age and sex. Significant deviations and distinct craniofacial patterns were found in children, young adults and adults with PWS compared with the control group. Children showed retrognatic mandible with a skeletal class II relationship, posterior growth direction and longer anterior face height. The young adults had smaller cranial base angle, a skeletal class II pattern and a higher anterior lower face than the control group. Adults with PWS had a prognathic mandible, skeletal class III relationship with anterior growth direction, more retroclined lower incisors and proclined upper incisors than the controls. Similar results were found when comparing the three groups with PWS; the adults had a prognathic mandible, skeletal class III pattern and anterior growth direction. Children had a retropositioned mandibula, skeletal class II relationship and posterior growth direction. CONCLUSION: This study may contribute to a better understanding of the craniofacial growth pattern in children, young adults and adults with PWS and may have a clinical importance when planning dental treatment, such as prosthodontics and/or orthodontics.

Experiences of daily life and oral rehabilitation in oligodontia - a qualitative study.

OBJECTIVE: Quantitative research indicate increased anxiety and poorer mental health related quality of life (QoL) in individuals with oligodontia (congenital absence of six or more teeth). The aim of this qualitative study was to complement and explore the individuals' experiences of life and oral rehabilitation, hopefully improving the care for these patients. MATERIAL AND METHODS: Twelve participants (6 females, 6 males, aged 21-48) with oligodontia and experiences of comprehensive dental treatments, consented to participate in a semi-structured interview. The questions in the interview guide were based on previous research and clinical experience and included both open (i.e. how is your life?) and specific questions (i.e. do health care personnel know enough about your condition?). The interview transcripts were coded and analysed using a phenomenological method of analysis. The Regional Ethics Committee approved the study. RESULTS: The following themes grew out of the data; 'feeling of being different', 'the burden of treatment', 'shared decision-making', 'treatment increases self-esteem' and 'use of coping strategies'. Psychological distress and reduced QoL seemed to be related to negative aspects of the themes, which covered unacceptable aesthetics, reduced orofacial function, the long-term process of oral rehabilitation, and negative experiences with healthcare services. The informants used problem focused and emotionally focused strategies to meet these challenges. Finalizing oral rehabilitation and shared decision making were positive aspects of the themes. CONCLUSION: All themes expressed by the participants were of importance for experienced QoL and psychological distress, and should be acknowledged by health care personnel when planning and performing treatment.

Gastro-oesophageal reflux - an important causative factor of severe tooth wear in Prader-Willi syndrome?

BACKGROUND: Prader-Willi syndrome (PWS) is the most common genetic human obesity syndrome and is characterized by hypotonia, endocrine disturbances, hyperphagia, obesity and mild mental retardation. Oral abnormalities, such as decreased salivary flow rates and extreme tooth wear, have also been described. Studies have shown a significant increase in reflux symptoms in individuals with obstuctive sleep apnoea syndrome and increased BMI, both of which are typical findings in PWS. Gastro-oesophageal reflux disease (GORD) has been identified in some individuals with PWS and is a significant intrinsic factor in dental tooth wear. The aim of this study was therefore to estimate the prevalence of GORD in adults and children and to evaluate a possible correlation between GORD and tooth wear in adults with PWS. They were all registered at the TAKO-centre. RESULTS: Twenty-nine individuals, 17 adults with a mean age of 32.6 years (range 18-48) and 12 children with a mean age of 8.8 years (range 3-17), agreed to undergo 24-hour oesophageal pH monitoring, and 90% of those enrolled managed to complete the examination. Four children and eleven adults were diagnosed with pathological gastro-oesophageal reflux, which is defined as acid exposure (pH less than 4) more than 3.6 or 4.3 percent of the time, respectively. Manometry performed in the adult group showed a pathologically high lower oesophageal sphincter pressure in four of the five individuals who had normal oesophageal pH values (pH under 4 less than 4.3% of the time). The two groups (reflux and non-reflux) were well balanced according to BMI, genotype, tooth grinding and hyposalivation. However, twice as many individuals in the reflux group as in the non-reflux group reported high consumption of acidic foods and drinks. Increased tooth wear was significantly correlated with GORD in the two groups (reflux n=6 and non-reflux n=6). CONCLUSIONS: The prevalence of gastro-oesophageal reflux is high in individuals with PWS. Tooth wear was strongly associated with GORD and acidic drinks, and both may be important aetiological factors underlying the extreme tooth wear in this group. Our data suggest a need for routine screening for GORD and dental wear in young individuals with Prader-Willi syndrome.

Associations between ectodermal dysplasia, psychological distress and quality of life in a group of adults with oligodontia.

OBJECTIVE: The aim of this study was to assess demographics, self-reported signs of ectodermal dysplasia (problems with hair, nails, skin and sweat glands), present teeth, previous dental treatment, psychological distress and QoL in individuals with oligodontia, and to explore the associations between these factors. We also aimed to compare the level of psychological distress and QoL between the study group and normative samples. METHODS: Forty-seven individuals with oligodontia registered at a resource centre in Norway were included in the study. The participants completed self-administered questionnaires on demographics, ED signs, dental treatments, psychological distress and QoL (overall, health-related- and oral health-related QoL). Relevant statistics (independent t-test, correlation analysis and hierarchical multiple regressions) were used. RESULTS: Thirty-five participants reported ED signs. Forty-one participants had tooth replacements (nine had removable dentures). Sixteen had ≤10 present teeth, 13 perceived dry mouth and seven were unemployed. Persons with ≤10 present teeth had higher anxiety- and depression-scores than those having >10 present teeth. Unemployment, dry mouth and removable dentures indicated poor health-related- and oral health related QoL. Compared to a normative sample; the study group had significantly poorer mental health (MH)-related QoL, mean (SD); (51.1(8.2) versus 46.8(9.3), p < .001) and more anxiety, mean (SD); (4.5(3.1) versus 6.7(3.6), p < .001). ED signs and treatments were most important for psychological distress and MH related QoL (MCS), whereas demographic parameters were most important for the other QoL measures. CONCLUSIONS: The psychological burden of oligodontia is significant, emphasizing the importance of a holistic approach by caregivers.

Microscopic structure of dental hard tissues in primary and permanent teeth from individuals with Prader-Willi syndrome.

OBJECTIVE: severe tooth wear, in terms of both erosive wear and attrition, is a significant problem in individuals with Prader-Willi syndrome (PWS). The purpose of the present study was to describe the structure of enamel and dentine in primary and permanent teeth from individuals with PWS. DESIGN: thirty-two primary and 10 permanent teeth representing 16 individuals with PWS were investigated in the study. The enamel surface was studied using scanning electron microscopy (SEM). The microscopic structure of enamel and dentine was studied using SEM, microradiography and light microscopy. RESULTS: the microscopic structure of enamel and dentine was found to be normal with the exception of a slight increase of interglobular dentine (IGD). Severe erosive defects were observed in primary teeth and also in permanent teeth with long exposure to the oral environment. CONCLUSION: the erosive enamel defects in individuals with PWS seem more related to the factors in the oral environment than to enamel structure which appeared normal. The occurrence of IGD indicate deficient mineralization but is probably of minor clinical significance. Gastro-oesophageal reflux is worthy of further investigation in individuals with Prader-Willi syndrome.

Saliva in Prader-Willi syndrome: quantitative and qualitative characteristics.

OBJECTIVE: To evaluate salivary flow rates and assess whole salivary total protein, MUC7 and cystatin in individuals with Prader-Willi syndrome (PWS) compared with healthy controls. DESIGN: The participants were forty-eight individuals with PWS (mean age 20.2 ± 9.5) and an age- and sex-matched control group. Flow rates of unstimulated whole saliva (UWS), stimulated whole saliva (SWS), submandibular/sublingual (SS), and parotid saliva (PS) were recorded (ml/min) and unstimulated whole saliva used for further protein analysis. Total protein concentration was determined via the bicinchoninic acid method, and MUC7 and cystatin levels via a Dot Blot. RESULTS: Mean UWS (0.12 ± 0.11 vs. 0.32 ± 0.20, p<0.001), SWS (0.41 ± 0.35 vs. 1.06 ± 0.63, p<0.001) and SS (0.27 ± 0.19 vs. 0.50 ± 0.29, p<0.001) salivary flow rates were significantly lower in PWS compared with controls. No significant difference was found in PS flow rate between the two groups. The mean total protein concentration (mg/ml) was 3.19 ± 3.04 in PWS compared with 1.32 ± 1.11 in controls (p<0.001). Median concentration of MUC7 (mg/ml) was 1.29 (0.11-10.85) in the PWS group, and 0.39 (0.03-2.22) in the control group (p<0.001). No significant difference was found in cystatin concentration between the groups. The output of proteins did not differ significantly between PWS and controls. CONCLUSION: With the exception of parotid saliva, salivary flow rates were lower among individuals with PWS than in their matched controls. Saliva protein concentrations in UWS were high compared with the healthy group, although the protein output did not differ significantly.

Severe tooth wear in Prader-Willi syndrome. A case-control study.

BACKGROUND: Prader-Willi syndrome (PWS) is a rare complex multsystemic genetic disorder characterized by severe neonatal hypotonia, endocrine disturbances, hyperphagia and obesity, mild mental retardation, learning disabilities, facial dysmorphology and oral abnormalities. The purpose of the present study was to explore the prevalence of tooth wear and possible risk factors in individuals with Prader-Willi syndrome. METHODS: Forty-nine individuals (6-40 years) with PWS and an age- and sex-matched control group were included. Tooth wear was evaluated from dental casts and intraoral photographs and rated by four examiners using the Visual Erosion Dental Examination (VEDE) scoring system and the individual tooth wear index IA. In accordance with the VEDE scoring system, tooth wear was also evaluated clinically. Whole saliva was collected. RESULTS: Mean VEDE score was 1.70 ± 1.44 in the PWS group and 0.46 ± 0.36 in the control group (p < 0.001). Median IA was 7.50 (2.60-30.70) in the PWS group and 2.60 (0.90-4.70) among controls (p < 0.001). In the PWS group tooth wear correlated significantly with age (VEDE; r = 0.79, p < 0.001, IA; r = 0.82, p < 0.001) and saliva secretion (VEDE; r = 0.46, p = 0.001, IA; r = 0.43, p = 0.002). Tooth grinding was also associated with tooth wear in the PWS group, as indicated by the mean VEDE 2.67 ± 1.62 in grinders and 1.14 ± 0.97 in non-grinders (p = 0.001) and median IA values 25.70 (5.48-68.55) in grinders and 5.70 (1.60-9.10) in non-grinders (p = 0.003). Multivariate linear regression analysis was performed with tooth wear as the dependent variable and PWS (yes/no), age, tooth grinding and saliva secretion as independent variables. PWS (yes/no), age and tooth grinding retained a significant association with tooth wear, VEDE (p < 0.001) and log IA (p < 0.001). The only factor significantly associated with tooth wear in the control group was age. CONCLUSIONS: Our study provides evidence that tooth wear, in terms of both erosion and attrition, is a severe problem in Prader-Willi syndrome. There is therefore considerable need for prosthodontic rehabilitation in young adults with PWS.

Salivary flow rate and oral findings in Prader-Willi syndrome: a case-control study.

BACKGROUND. Prader-Willi syndrome (PWS) is a rare complex multisystemic genetic disorder. AIM. The objective of this study was to provide a systematic assessment of whole saliva secretion and oral manifestations associated with PWS. DESIGN. Fifty individuals (5-40 years) with PWS and an age- and sex-matched control group were included. Whole saliva was collected. All participants underwent an anamnestic interview. Radiological and dental clinical examinations were carried out to identify hypodontia, dental caries, enamel defects and gingival inflammation. RESULTS. Mean whole salivary flow rate was 0.12 ± 0.11 mL/min in the study group compared with 0.32 ± 0.20 mL/min in the control group (P < 0.001). Hypodontia was significantly more common in PWS (P < 0.001), and dental caries in the age group >19 years was significantly lower in PWS (P = 0.04) compared with the controls. There was no significant difference in the prevalence of dental caries in the primary dentition or in the frequency of enamel defects in the permanent dentition between the two groups. Median Gingival Index was significantly higher in the Prader-Willi group compared with the controls (P = 0.02). CONCLUSIONS. Low salivary flow is a consistent finding in PWS. Nevertheless, despite dry mouth and dietary challenges, dental caries is not increased in Norwegian individuals with PWS.

Orofacial dysfunction in individuals with Prader-Willi syndrome assessed with NOT-S.

OBJECTIVE: The objective of the study was to evaluate orofacial dysfunction in individuals with Prader-Willi syndrome (PWS) and compare it with a healthy reference group. METHODS AND MATERIALS: The Nordic Orofacial Test-Screening (NOT-S) protocol was used for evaluation of orofacial function in 45 (23 Male, 22 Female) individuals with PWS, aged 19.8 ± 9.5 years, and a reference group of 40 (18 M, 22 F) healthy individuals, aged 24.0 ± 16.3 years. RESULTS: The NOT-S score was markedly higher for the individuals with PWS than for the healthy reference group (3.9 ± 2.1 vs 0.3 ± 0.5, p < 0.001). The most common domains of dysfunction in individuals with PWS were Oral motor function (60.0%), Habits (55.6%), Face at rest (53.3%), Speech (44.4%), Drooling (44.4%) and Breathing (42.2%). CONCLUSIONS: Eighty-seven per cent of the participants with PWS demonstrated dysfunction in two or more domains, particularly in the domains Oral motor function, Habits and Face at rest.

Oral findings in adults with osteogenesis imperfecta.

This paper describes oral findings in an adult population with osteogenesis imperfecta (OI) in Norway (n=94). All participants underwent a structured interview and an oral examination. Panoramic radiographs were analyzed. The findings were compared with data from other Nordic epidemiological studies. Seventeen individuals (19%) had clinical signs of dentinogenesis imperfecta (DI). Persons with OI had twice as many missing teeth as the general population, and the number of endodontically treated teeth was higher than in the general population. All persons in the study had an acceptable state of tooth tissue loss. Almost all (97%) of the participants in the study group visited a dentist or a dental hygienist regularly. The results of the study indicated a low prevalence of clinical DI compared with previous reported studies. Oral health was not as good in the population with OI when compared with the general population, although daily oral health habits were good and dental visits were regular.