Natural History of Mandibular Function in Spinal Muscular Atrophy Types 2 and 3.

Background: Hereditary proximal spinal muscular atrophy (SMA) is characterized by abnormal alpha motor neuron function in brainstem and spinal cord. Bulbar dysfunction, including limited mouth opening, is present in the majority of patients with SMA but it is unknown if and how these problems change during disease course. Objective: In this prospective, observational, longitudinal natural history study we aimed to study bulbar dysfunction in patients with SMA types 2 and 3. Methods: We included 44 patients with SMA types 2 and 3 (mean age was 33.6 (95% CI 28.4;38.9) and re-examined them after on average 4 years. None were treated with SMN-modulating treatments before or during the course of this study. Longitudinal assessments included a questionnaire on mandibular and bulbar function, the Mandibular Function Impairment Questionnaire (MFIQ), and a clinical examination of masticatory performance, maximum voluntary bite force, and mandibular movements including the active maximal mouth opening. Results: We found significant higher MFIQ scores and a significant decrease of all mandibular movements in patients with SMA type 2 (p < 0.001), but not in SMA type 3. Masticatory performance and maximum voluntary bite force did not change significantly. Mean reduction of active maximal mouth opening at follow-up was 3.5 mm in SMA type 2 (95% CI: 2.3; 4.7, p < 0.001). SMA type 2 was an independent predictor for a more severe reduction of the mouth opening (ß= -2.0 mm (95% CI: -3.8; -0.1, p = 0.043)). Conclusions: Bulbar functions such as mandibular mobility and active maximum mouth opening decrease significantly over the course of four years in patients with SMA type 2.

Diagnostics and Management of Pediatric Headache: An Exploratory Study among Dutch Physical Therapists.

Physiotherapists are often part of a multidisciplinary treatment plan for children with headaches. The literature on physical therapeutic diagnostics and management of headaches is often focused on adults. To gain insight, identify knowledge gaps, and increase the evidence needed for clinical physical therapeutic practice with children with headaches, an exploratory method is warranted. The purpose of this study was to describe the views, beliefs, and experiences of physical therapists regarding diagnostics and treatment options for children with headaches. The method consisted of a survey and two peer consultation group meetings. A total of 195 individual surveys were returned and 31 out of 47 peer consultation groups participated. Most participants were specialized in pediatric physical therapy (93.3%). They use the 4P-factor model (predisposing, precipitating, perpetuating, and protective factors) as a guiding principle in the diagnostic and therapeutic process in children with headaches. This model helps to organize and to understand how a variety of factors interact in a biopsychosocial relationship. Pediatric physical therapists focus their treatments on factors interfering with movement and functional abilities of the child with headaches. Knowledge of how temporomandibular disfunction can relate to headaches is currently insufficient for pediatric physical therapists.

Biomechanical properties of different endocrown designs on endodontically treated teeth.

OBJECTIVE: To compare the biomechanical properties of different endocrown designs on endodontically treated teeth with an extensive defect in the mesial wall using a three-dimensional finite element method (3D FEM). METHODS: Four finite element analysis models were designed and built up based on different endocrown configurations in a mandibular molar. One model was designed as a butt joint preparation with 2 mm occlusal thickness(control), the other three models were butt joint designs with different distances between the bottom of the mesial wall preparation and the cemento-enamel junction (CEJ): 2 mm, 1 mm and 0 mm respectively. A vertical load parallel with the longitudinal axis of the tooth and an oblique load with a 45°angle to the longitudinal axis were applied to the occlusal surfaces. The maximum Von Misses (VM) stresses and stress distribution patterns were calculated and compared. Weibull risk-of-rupture analysis was used to analyze the survival probability of the restorations and tooth in the different models. RESULTS: For the restoration, the model with a mesial wall destruction at the level of CEJ showed much higher risk of failure than other models. Overall, none of the four models showed failure. Under oblique loading, VM stress in the cement layer of the models with a mesial wall defect was higher than in the control model. In the dentin, the highest VM stresses were found in the peri-cervical dentin. Under the oblique loading, the model with the mesial wall destruction at the level of CEJ restored by endocrown showed the highest risk of failure. CONCLUSION: Under the oblique loading, with the increase of the simulated defect in the mesial wall, the peak VM stress values in the cement layer increased accordingly. In the model with a mesial wall defect up to the level of CEJ risk of failure was highest in the cervical dentin.

Interprofessional learning in a student-run dental clinic: The effect on attitudes of students in oral healthcare.

The purpose of this study was to gain insight into change in attitudes held by students in oral healthcare about interprofessional learning and collaboration after one year of work in a student-run dental clinic (SRDC). Third- and fourth-year bachelor of dental hygiene students (n = 221) and first- and second-year master of dentistry students (n = 203) participated in baseline and follow-up measurements and completed 570 questionnaires. The Readiness for Interprofessional Learning Scale (RIPLS) was used to measure changes in attitudes toward Interprofessional Education (IPE) during participation in the SRDC. To validate the questionnaire for the setting, professional groups, and wording of RIPLS, we performed exploratory and confirmatory factor analyses. Two modified subscales remained: "Teamwork & Collaboration" and "Negative Professional Identity." Mixed linear models were used to assess relationships between students' attitudes toward IPE and participation in the SRDC. Overall, the students had positive attitudes toward IPE. At baseline, the attitudes of the dental hygiene and dentistry students were almost equally positive. After one year, dental hygiene students demonstrated a significantly more positive attitude toward collaborative learning and teamwork than the dentistry students. Further research should investigate whether the positive attitudes impact behavior in professional practice.

An innovative interprofessional dental clinical learning environment using entrustable professional activities.

INTRODUCTION: Changes in society, new public demands for dental care and contemporary educational insights have influenced dental education worldwide and demand a renewed perspective. Following this perspective, an innovative interprofessional dental Master curriculum was developed at Radboud University Nijmegen in the Netherlands. EDUCATIONAL PRINCIPLES: The curriculum is based on five contemporary educational principles and the core of the curriculum consists of a Student Run Dental Clinic that is fully run by students under professional supervision. THE NEW CURRICULUM: In the Student Run Dental Clinic, Master dental students and Bachelor oral hygiene students are responsible for the care of approximately 750 patients. The students work within the same clinic for 3 years and patients receive oral health care from the same students over a long period. The clinic is a longitudinal cross-disciplinary clinic with different dental subdisciplines. Entrustable professional activities (also known as EPAs), to our knowledge not yet widely used in dental education, were introduced to facilitate learning and assessment. Fourteen EPAs have been developed to stimulate interprofessional education and learning. Of these, five EPAs are identical for the dental and oral hygiene curriculum, leading to extended interprofessional education and learning in the Student Run Dental Clinic. DISCUSSION: Preliminary results show that EPAs are generally well received by supervisors and students. CONCLUSION: To monitor and investigate the exact effect of the interventions and underlying mechanisms, a research programme on interprofessional learning, practice-based learning and EPAs and entrustment in dental education was recently set up.

Mandibular residual ridge morphology in relation to complete dentures and implant overdentures-Part I: Predictors for perceived conventional denture stability.

BACKGROUND: There is lack of reliable predictors for success of conventional complete denture (CCD) therapy, which in turn might affect the effectiveness of subsequent implant-retained overdenture (IOD) therapy. PURPOSE: To investigate relationships between digitally obtained geometrical mandibular residual ridge measures and perceived CCD-stability. MATERIALS AND METHODS: 30 CCD wearing patients (67.9 ± 7.0 years) for whom a new set of CCDs was advised, were treated with new CCDs. Digitalized mandibular gypsum models were measured using the Geomagic Studio 2013 software. Data were obtained for (1) height, width, and cross-section surface area of the residual ridge at different locations (midline, premolar, and anterior edge of retromolar pad) and (2) denture base surface area. Scatter plots and multivariate regression analyses were used to investigate associations between the geometric data and denture base surface area, and correlated with denture stability scores (Spearman rank test). RESULTS: Scatter plots showed that best model fit for denture base surface area was mean ridge height (R2 = 0.906). Multivariate regression showed that height at premolar location (p = 0.001) had largest effect on denture base surface area (R2 = 0.796). Ridge morphology variables, except width at midline location, were significantly correlated with CCD-stability (p-values <0.05). CCD-stability was significantly correlated with denture base surface area (p ≤ 0.001). CONCLUSION: Residual ridge height at premolar location was most predictive for denture base surface area and perceived CCD-stability.

Mandibular residual ridge morphology in relation to complete dentures and implant overdentures-Part II: Predictors for effectiveness of implant overdenture therapy.

BACKGROUND: The significance of mandibular residual ridge height and satisfaction with conventional complete dentures (CCD) as predictors for the added value of implant-overdenture (IOD) therapy is unknown. PURPOSE: To investigate the predictive value of thresholds for (1) residual ridge height at premolar location (PRH), and (2) satisfaction with CCD-stability for the added value of two intraforaminal implants supporting the mandibular CCD. METHODS: Thirty CCD wearing patients (67.9 ± 7.0 years) for whom a new CCD was advised, received a new CCD. Mandibular gypsum models were digitally measured. After 3 months free of complaints (T1), perceived CCD-stability was evaluated, and participants received two intraforaminal implants. At T1 and T2 (3 months free of complaints after IOD therapy) participants completed OHIP14-CN, and denture satisfaction (VAS) questionnaires, and performed mixing ability tests. Participants were grouped according to PRH of ≥6.15 mm versus < 6.15 mm, and perceived CCD-stability satisfied vs. dissatisfied. Scores at T2 were compared to T1 (paired t-tests). Predictive values of PRH and CCD-stability were analyzed with logistic multivariate regression models. RESULTS: At T2, only participants with PRH of <6.15 mm or dissatisfied with CCD-stability had significant lower OHIP-total and domain scores for 'physical pain' and 'physical disability' and significantly higher VAS scores for perceived chewing function, denture retention and oral comfort. Regression analyses showed that participants with PRH of <6.15 mm, or dissatisfied with CCD-stability had significantly higher chance for lower OHIP-total and domain scores 'physical pain' and 'physical disability', and for higher VAS scores for perceived chewing function, denture retention and oral comfort at T2. Masticatory performance improved significantly after IOD therapy, but independent of PRH and CCD-stability. CONCLUSION: PRH and satisfaction with CCD-stability were adequate prognostic indicators for improvement of oral health-related quality of life and denture satisfaction by mandibular IOD therapy.

Physical Treatments Reduce Pain in Children with Tension-Type Headache: A Systematic Review and Meta-Analysis.

AIMS: To assess the effectiveness of a variety of physical treatments in the management of tension-type headache (TTH) in children. METHODS: This review is reported in accordance with the PRISMA guidelines and was registered in the PROSPERO database (CRD42014015290). Randomized and nonrandomized controlled trials that examined the effects of all treatments with a physical component in the management of TTH in children and compared these treatments to a placebo intervention, no intervention, or a controlled comparison intervention were included. The Physiotherapy Evidence Database (PEDro) criteria for bias assessment and the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) Working Group criteria were used to assess the quality of the body of evidence. The outcome measures were pain, functioning, and quality of life. Only RCTs were included in the meta-analyses. RESULTS: An initial search produced 10,464 published articles. Of these, 17 were relevant trials, including 1,815 participants. The overall GRADE rating of the included studies was moderate, and 11 of the 17 studies could be used in the meta-analyses. The effectiveness of physical treatments in terms of a reduction of pain of 50% or more showed a risk ratio (RR) of 2.37 (95% CI: 1.69 to 3.33). Relaxation training was the most evaluated intervention and proved to be significantly effective (RR: 3.00 [95% CI: 1.94 to 4.63]). In children having TTH combined with temporomandibular disorders, occlusal appliances were effective (RR: 2.58 [95% CI: 1.37 to 4.85]). CONCLUSION: This review supports the use of physical treatments to reduce pain in children with TTH.

A systematic review of interventions after restoring the occluding surfaces of anterior and posterior teeth that are affected by tooth wear with filled resin composites.

OBJECTIVES: The aim of this systematic review was to assess intervention rates of direct composite restorations in the worn dentition based on data published in clinical trials. METHODS: Searches of electronic data bases, grey Literature and hand searches were completed, and selection criteria were applied at the title, abstract and full paper stages. Unavailable full papers or papers with unsuitable data were excluded. A reference search was conducted, and a final set of papers were selected for data analysis. Data were extracted and noted as any intervention required or performed, or intervention free. Descriptive statistics were used to summarise the findings and the odds ratios were calculated. RESULTS: 1683 titles were found in the initial searches. On application of selection criteria, 140 abstracts were selected (Kappa 0.885), 17 papers were chosen by 3 reviewers (Kappa 0.914 - 0.942) and 12 selected for statistical analysis (Kappa 0.924). A total of 3540 composites in 386 participants were analysed, with 1919 in the anterior region, and 1044 in the posterior region of these 11.7 % required intervention. Annual Intervention Rates (AIR) ranged from 0.8 to 17.9% reflecting the variation in reporting. CONCLUSION: There was wide variation between studies on the type of intervention. Overall the intervention rate of 11.6 % shows a favourable outcome but suggests some form intervention may be needed. CLINICAL SIGNIFICANCE: Direct composites remain a viable option to treat tooth wear but the outcome varies. Provided patients appreciate that some maintenance may be needed they are an effective intervention.

Wish-fulfilling medicine and wish-fulfilling dentistry.

OBJECTIVES: to explain the practice of wish-fulfilling medicine and how it relates to dentistry. SOURCES: Relevant papers, and reports from authoritative institutions were identified in Pubmed and Google Scholar. RESULTS: Wish-fulfilling medicine refers to services provided by professionals using medical methods in a medical setting to address non-medical wishes of patients. Care-providers, medical industries, and health-insurance companies also contribute to wish-fulfilling in medicine and dentistry. Various concepts of health and illness compounded by blurred borders between health and illness offer an unstable foundation for wish-fulfilling medicine, and growing demands for these services where healthcare resources are limited can displace medically necessary treatments. Moreover, treatments without a medical or a dental necessity, can be harmful and bear the risk of futile or excessive treatments not in patients' long-term interest. Examples in dentistry are found in the field of cosmetic interventions, prosthodontics and orthodontics, where perceptions of small 'deviations' from normality prompt wishes or recommendations for intervention. Ethically, wish-fulfilling services confront the principles of the common morality if the autonomy of a patient is compromised, beneficence is unclear, harm is foreseeable, or distributive justice is compromised. Wish-fulfilling dental treatment can be restricted by legislation if it conflicts with safe, effective and efficient care, or if it interferes with patient's real needs or undermines established professional standards. CONCLUSIONS: The general understanding of wish-fulfilling medicine including its ethical and legal themes is relevant to dentistry. CLINICAL RELEVANCE: Ethical considerations and legislation can guide a dentist to reflect critically on clinical decisions regarding wish-fulfilling dentistry.

Coherence of jaw and neck muscle activity during sleep bruxism.

BACKGROUND: Studies have shown co-contraction of jaw and neck muscles in healthy subjects during (sub) maximum voluntary jaw clenching, indicating functional inter-relation between these muscles during awake bruxism. So far, coherence of jaw and neck muscles has not been evaluated during either awake or sleep bruxism. OBJECTIVE: The objective of this study was to evaluate the coherence between jaw and neck muscle activity during sleep bruxism. METHODS: In a cross-sectional observational design, the electromyographic activity of jaw (masseter, temporalis) and neck (sternocleidomastoid, trapezius) muscles in individuals with "definite" sleep bruxism was measured using ambulatory polysomnography (PSG). Coherence for masseter-temporalis, masseter-sternocleidomastoid and masseter-trapezius was measured during phasic and mixed rhythmic masticatory muscle activity episodes using coherence-analysing software. Outcome measures were as follows: presence or absence of significant coherence per episode (in percentages), frequency of peak coherence (FPC) per episode and sleep stage. RESULTS: A total of 632 episodes within 16 PSGs of eight individuals were analysed. Significant coherence was found between the jaw and neck muscles in 84.9% of the episodes. FPCs of masseter-temporalis were significantly positively correlated with those of masseter-sternocleidomastoid or masseter-trapezius (P < .001). Sleep stages did not significantly influence coherence of these muscular couples. CONCLUSION: During sleep bruxism, jaw and neck muscle activation is significantly coherent. Coherence occurs independently of sleep stage. These results support the hypothesis of bruxism being a centrally regulated phenomenon.

Food avoidance is associated with reduced dentitions and edentulousness.

OBJECTIVES: To investigate associations between food avoidance and dental status, age, gender, and socio-economic status (SES). MATERIALS AND METHODS: The Chinese sample comprised 1463 dentulous (≥ 1 tooth in each jaw) and 124 edentulous (in one or both jaws) participants aged ≥ 40 yrs. The Vietnamese sample comprised 2820 dentulous and 253 edentulous participants aged ≥ 20 yrs. Food avoidance due to chewing difficulties was scored for regionally common 4 soft and 4 hard foods. Dental status was classified according to the multi-level hierarchical dental functional classification system (HDFC) based on the number and location of teeth and posterior occlusal pairs. Associations were analyzed using multivariate logistic regression analyses. RESULTS: For dentulous participants, the chance of avoiding foods was significantly larger with < 10 teeth in each jaw (OR = 2.26 (Chinese sample), respectively 1.74 (Vietnamese sample)), incomplete anterior region (OR = 1.78, respectively 1.84), "impaired" premolar region (OR = 2.22, respectively 1.71), or "impaired" molar region (OR = 2.46, respectively 1.84). Edentulous participants had twice the chance of avoiding foods (OR = 2.01 respectively 2.20). Avoiding foods was significantly associated with higher age. Participants of low SES (Chinese sample, OR = 1.93) and females (Vietnamese sample, OR = 1.27) had a larger chance of avoiding foods. CONCLUSIONS: Avoiding foods was significantly associated with reduced dentitions, edentulousness, and higher age; low SES only in the Chinese and being female only in the Vietnamese sample. CLINICAL RELEVANCE: Incomplete anterior regions, "impaired" premolar or molar regions, and especially edentulousness can be considered significant risk indicators for food avoidance.

Perceptions of interprofessional collaboration in education of dentists and dental hygienists and the impact on dental practice in the Netherlands: A qualitative study.

INTRODUCTION: The purpose of this study was to evaluate the perceptions of dentists and dental hygienists regarding their own and each other's roles in interprofessional collaboration following a clinical interprofessional educational programme (CIEP) as part of their graduate programme at Radboud university medical center (Radboudumc) and HAN University of Applied Sciences (HAN UAS), Nijmegen, the Netherlands, respectively. Perceptions were obtained at the end of their study (2014) and two years after their graduation (2016). METHODS: A qualitative study was conducted using a questionnaire with open-ended questions. Sixty-two dentists and thirty-eight dental hygienists were invited. Theory-based analyses were applied in combination with principles of Grounded Theory to analyse and synthesise the collected data from the open-ended questions. RESULTS: At baseline, 100% responded. At follow-up, thirty-two dentists (51.6%) and twenty-six dental hygienists (68.4%) responded; twenty-seven dentists (43.5%) and eighteen dental hygienists (47.4%) were included. Many similarities were found between baseline and follow-up regarding perceptions of each other's expertise and responsibility, learning from and with each other, and the behaviour of students and the "novice" professionals in interprofessional collaboration. Both dentists and dental hygienists experienced the CIEP as useful for interprofessional collaboration. The "novice" dentists and dental hygienists indicated that in dental practices interprofessional collaboration was less common. CONCLUSION: The CIEP resulted in more understanding amongst dentists and dental hygienists with regard to interprofessional roles, but in practice the "novice" dentists and dental hygienists face difficulties in applying the interprofessional roles.

The relationship between masticatory ability, age, and dental and prosthodontic status in an institutionalized elderly dentate population in Qingdao, China.

OBJECTIVES: To identify relationships between masticatory ability and age, and dental and prosthodontic status amongst an institutionalized elderly dentate population in China. MATERIALS AND METHODS: A sample of 512 elders living in eight nursing homes in Qingdao was categorized based on a hierarchical dental functional classification system with and without tooth replacements. Masticatory disability scores (MDSs) were analyzed using multiple regression models with only age, and age and dentition variables for participants having ≥ 10 natural and those having < 10 natural teeth in each jaw. RESULTS: Overall, associations between MDS and age, number of teeth, and number of teeth replaced by dental prostheses were identified. For participants having ≥ 10 natural teeth in each jaw, no significant associations between MDS and age and dental and prosthodontic status were found. Participants having < 10 natural teeth in each jaw had higher MDS (increasing chewing difficulties) at higher ages. However, when "premolar region sufficient" and "molar region sufficient" were included, MDS was not associated with age, but with these dentition variables. For participants having ≥ 10 teeth including prosthodontically replaced teeth in each jaw, age was the only variable associated with MDS. For participants having < 10 teeth including teeth replaced in each jaw, the significant factor was "premolar region sufficient." Overall, lower MDS was associated with increasing number of teeth, as well as with increasing number of teeth replaced by dental prostheses. CONCLUSIONS: In this population of institutionalized dentate elderly, masticatory ability was significantly associated with dental and prosthodontic status. CLINICAL RELEVANCE: For institutionalized elderly, having less than ten natural teeth in each jaw is associated with chewing problems. Most important dentition factor is the presence of three to four premolar pairs. Teeth added by partial removable dental prostheses compensate impaired masticatory ability due to tooth loss for 50% compared to natural teeth.

Association between self-reported bruxism and anger and frustration.

BACKGROUND: Even though bruxism has been shown to be associated with several psychological factors, few studies have been performed on its relationships with anger and frustration. OBJECTIVE: This study aimed to determine the association between self-reported awake and sleep bruxism and anger and frustration. METHODS: In this longitudinal observational study, 55 healthy adult participants with "possible" bruxism reported their experienced level of bruxism and several psychosocial factors and lifestyle factors for 28 consecutive days using a personal logbook. The logbook consisted of a daily diary and a weekly questionnaire composed of Dutch versions of validated questionnaires. The primary outcome data were analysed using multiple regression models. RESULTS: An increase in SB of 1 unit (on a scale ranging from 1 to 10) was associated with an increase in the anger-scale of 0.03 units, and the frustration-scale of 0.04 units. However, the random intercepts were 0.22 for anger and 0.19 for frustration, meaning that there were major differences between individuals. For awake bruxism (AB), the effects were an increase of 0.04 for anger with a random intercept of 0.21 and an increase of 0.03 for frustration with a random intercept of 0.06. The effects of anger and frustration on both SB and AB were not statistically significant. CONCLUSION: The association between anger and frustration and self-reported bruxism is small on group level. In individual cases, anger and frustration and self-reported bruxism may be co-existent.

Masticatory muscle stretching for the management of sleep bruxism: A randomised controlled trial.

BACKGROUND: Sleep bruxism is a phenomenon associated with masticatory muscle hyperactivity. While stretching of limb and trunk muscles has been extensively studied for musculoskeletal disorders, little is known about the effectiveness of stretching of masticatory muscles in the management of bruxism. OBJECTIVE: The aim of this study is to determine the effectiveness of stretching of the masticatory muscles for sleep bruxism. METHODS: Twenty four pain-free individuals with sleep bruxism were randomly assigned to either an intervention group or a control group. Both groups were given sleep hygiene advice and the intervention group additionally received muscle-stretching exercises for 10 days. Primary outcome measures, bruxism bursts and episodes per hour of sleep, were measured by ambulant polysomnography. Secondary outcome measures were among others pain-free active maximum mouth opening (MMO) and masseter pressure pain threshold (PPT). RESULTS: The number of bruxism episodes per hour of sleep increased more in the intervention group than in the control group (by 1.1 episodes, P = 0.066), as did the number of bruxism bursts per hour of sleep (by 8.6 bursts, P = 0.049). MMO and PPT increased significantly more in the intervention group (by 3.2 mm, P = 0.020; and by 1.0 kg/cm2 , P = 0.036, respectively). CONCLUSION: Static stretching of the masticatory muscles resulted in a minor increase in sleep bruxism episodes (not significant) and bursts (significant). It also led to a significant increase in MMO and PPT. Therefore, masticatory muscle stretching was not effective in reducing sleep bruxism in the absence of pain and/or dysfunction.

Masticatory efficiency in patients with partially dentate dentitions.

OBJECTIVES: To assess associations amongst masticatory performance, dental functional status, and perceived chewing problems with common soft and hard foods. MATERIALS AND METHODS: 387 adult participants with reduced natural dentitions were included and underwent an oral examination, completed a written structured questionnaire and performed a two-color chewing gum test for masticatory efficiency. A multivariate regression model was used to analyze associations between masticatory efficiency and a number of dental conditions, with age, gender and perceived chewing difficulties as background variables. Likelihood ratios were calculated to analyze the relationship between masticatory efficiency and dental conditions within a validated hierarchical dental functional classification system expressed by (1) number of teeth in upper and lower jaw, (2) completeness of anterior regions, (3) number of premolar occluding pairs, and (4) number of molar occluding pairs. RESULTS: The regression model showed a significant positive association between unmixed ratio and self-reported problems with chewing (p = .004), and age (p < 0.001), and negative associations with having a sufficient premolar region (p < 0.001). In the hierarchical dental functional classification system, the likelihoods of having a high unmixed ratio and chewing problems with hard foods were highest for the predictor 'less than 10 teeth in each jaw' (LRs 4.01, respectively 13.06). CONCLUSIONS: In partially dentates people, perceived chewing difficulties were associated with lower objective masticatory efficiency. Having fewer than 10 teeth in each jaw and having an impaired premolar region were best predictors for low masticatory efficiency. CLINICAL SIGNIFICANCE: This study shows that having fewer than 10 teeth in each jaw and having an impaired premolar region are associated with low masticatory efficiency and chewing problems. Preservation of at least 10 teeth in each jaw and 3 to 4 premolars is important for preventing chewing difficulties.

Correction to: The 3.5-year survival rates of primary molars treated according to three treatment protocols: a controlled clinical trial.

Mw. M. Mijan will defend her PhD thesis on 15th September 2017. Whilst reviewing her work in preparation to the event, we discovered a few irregularities that prompted a recheck of the database and ditto analyses. These activities have lead to a few textual changes in the publication.

Long-term follow-up indicates unimpaired oral health-related quality of life for people having shortened dental arches.

OBJECTIVES: To assess and analyse OHRQoL of people with shortened dental arches (SDA) in a long-term cohort study. METHODS: All participants of a long-term cohort study on SDA who were still attending the university dental clinic and still had an SDA (SDA group) with 3-5 posterior occluding pairs and intact anterior areas, an SDA plus removable dental prosthesis (SDA plus PRDP group) or complete dental arch (CDA group) completed the Dutch version of the Oral Health Impact Profile (OHIP-49NL) and additional questions on satisfaction with their dental status (yes/no). Mann-Whitney tests were performed for OHIP total scores and OHIP domain scores. The chance that the difference in median OHIP scores between the groups was larger than 6 OHIP units, was calculated by a bootstrapping procedure. RESULTS: 10 participants were eligible for SDA group and 11 for CDA group. The SDA plus PRDP group (n=1) was excluded from analyses. Mean follow-up period was 29.3±5.5 for SDA group and 36.7±5.5years for CDA group. Mean OHIP-49NL score was 13.9±10.9 for SDA group and 11.3±8.6 for CDA group. Differences in mean total scores and mean scores per domain were not statistically different. The probability that a difference in median OHIP total scores between groups was larger than 6 OHIP units was 0.25. Both groups showed high percentages of satisfaction with dental condition, except for dental appearance. CONCLUSION: OHRQoL of people with a long-term SDA condition was similar to that of people with CDA. CLINICAL SIGNIFICANCE: People having SDA for long periods are expected to report similar OHRQoL and satisfaction levels/oral comfort as people with CDA.

The effect of a daily application of a 0.05% chlorhexidine oral rinse solution on the incidence of aspiration pneumonia in nursing home residents: a multicenter study.

BACKGROUND: Dysphagia and potential respiratory pathogens in the oral biofilm are risk factors for aspiration pneumonia in nursing home residents. The aim of the study was to examine if the daily application of 0.05% chlorhexidine oral rinse solution is effective in reducing the incidence of aspiration pneumonia in nursing home residents with dysphagia. Associations between background variables (age, gender, dysphagia severity, care dependency, medication use, number of medical diagnoses, teeth and dental implants, and wearing removable dentures) and the incidence of aspiration pneumonia were also examined. METHODS: This study is a multicenter study in which for 1 year participants with dysphagia in the intervention group received the usual oral hygiene care with the addition of a 0.05% chlorhexidine oral rinse solution, whereas participants in the control group received only oral hygiene care. RESULTS: Data of 103 participants in 17 nursing homes were analyzed. Survival analysis showed no significant difference in the incidence of pneumonia between both groups (Cox regression, HR = 0.800; 95% CI [0.368-1.737], p = 0.572). Cox regression analysis for Functional Oral Intake Scale (FOIS)-level showed a significant risk of the incidence of pneumonia (HR = 0.804; 95% CI [0.656-0.986], p = 0.036). After adjustment for Group and FOIS-level, Cox multivariate proportional hazard regression analysis showed that the variables age, gender, Care-dependency Scale-score (CDS) number of diseases, medication use, number of teeth, and the presence of dental implants or removable dentures were not significantly associated with the incidence of pneumonia. CONCLUSIONS: Chlorhexidine oral rinse solution 0.05% as an adjunctive intervention in daily oral hygiene care was not found to reduce incidence of aspiration pneumonia. The requested number of participants to achieve sufficient power was not established and high drop-out rate and non-structural compliance was present. The power was considered to be sufficient to analyze the associations between the background variables and the incidence of pneumonia in the included nursing home residents with dysphagia. Dysphagia was found to be a risk factor for aspiration pneumonia. TRIAL REGISTRATION: Registration in The Netherlands National Trial Register: TC = 3515. Approval for the study was obtained from the Medical Ethical Committee of the Radboud University Medical Center (NL. nr:41,990.091.12).