Enhanced control of periodontitis by an artificial intelligence-enabled multimodal-sensing toothbrush and targeted mHealth micromessages: A randomized trial.

AIM: Treatment of periodontitis, a chronic inflammatory disease driven by biofilm dysbiosis, remains challenging due to patients' poor performance and adherence to the necessary oral hygiene procedures. Novel, artificial intelligence-enabled multimodal-sensing toothbrushes (AI-MST) can guide patients' oral hygiene practices in real-time and transmit valuable data to clinicians, thus enabling effective remote monitoring and guidance. The aim of this trial was to assess the effect of such a system as an adjunct to clinical practice guideline-conform treatment. MATERIALS AND METHODS: This was a single-centre, double-blind, standard-of-care controlled, randomized, parallel-group, superiority trial. Male and female adults with generalized Stage II/III periodontitis were recruited at the Shanghai Ninth People's Hospital, China. Subjects received a standard-of-care oral hygiene regimen or a technology-enabled, theory-based digital intervention consisting of an AI-MST and targeted doctor's guidance by remote micromessaging. Additionally, both groups received guideline-conform periodontal treatment. The primary outcome was the resolution of inflamed periodontal pockets (≥4 mm with bleeding on probing) at 6 months. The intention-to-treat (ITT) analysis included all subjects who received the allocated treatment and at least one follow-up. RESULTS: One hundred patients were randomized and treated (50 tests/controls) between 1 February and 30 November 2022. Forty-eight tests (19 females) and 47 controls (16 females) were analysed in the ITT population. At 6 months, the proportion of inflamed periodontal pockets decreased from 80.7% (95% confidence interval [CI] 76.5-84.8) to 52.3% (47.7-57.0) in the control group, and from 81.4% (77.1-85.6) to 44.4% (39.9-48.9) in the test group. The inter-group difference was 7.9% (1.6-14.6, p < .05). Test subjects achieved better levels of oral hygiene (p < .001). No significant adverse events were observed. CONCLUSIONS: The tested digital health intervention significantly improved the outcome of periodontal therapy by enhancing the adherence and performance of self-performed oral hygiene. The model breaks the traditional model of oral health care and has the potential to improve efficiency and reduce costs (NCT05137392).

Ill-fitting prosthesis is associated with an increased risk of elevated blood pressures.

OBJECTIVE: Previous studies focused on the benefits of adequate prosthodontic treatment, while few studies have investigated the prosthodontic-related risks to health. As a modifiable oral health indicator, the association of ill-fitting prosthesis (IFP) with hypertension has not been fully explored. METHODS: This cross-sectional study involved 158,659 adults in Beijing (2009-2017) receiving intra-oral examinations and blood pressure measurements. Logistic regression models were applied to assess the association of IFP with the prevalence of hypertension, systolic blood pressure (SBP) ≧ 140 mmHg and diastolic blood pressure (DBP) ≧ 90 mmHg, as well as subgroup analyses by different fixed IFP subgroups (according to involved teeth number) and removable IFP subgroup. We further investigated effect modifications among stratified populations. RESULTS: 158,659 individuals were included for analysis, 346 (26.86%) in IFP group and 27,380 (17.40%) in non-IFP group (p < 0.001) were hypertensive. After adjustment of sex, age, obesity, dyslipidaemia, diabetes, hsCRP, family history of CVD, self-reported smoking, self-reported drinking and WC, ORs of hypertension, SBP ≧ 140 mmHg and DBP ≧ 90 mmHg were 1.330 (95% CI: 1.162-1.522), 1.277 (95% CI: 1.098-1.486) and 1.376 (95% CI: 1.186-1.596), respectively (p < 0.05). Furthermore, after full adjustment, the number of involved teeth showed a significant incremental trend with hypertension risk in the population with and without IFP (p for trend <0.001). The IFP-blood pressure associations were more pronounced in females, 18-60 years, non-obese and diabetic participants. CONCLUSION: As a modifiable oral indicator, IFP was significantly associated with a higher risk of hypertension.

Impact of periodontitis on type 2 diabetes: a bioinformatic analysis.

BACKGROUND: Periodontitis is strongly associated with type 2 diabetes (T2D) that results in serious complications and mortality. However, the pathogenic role of periodontitis in the development of T2D and the underlain mechanism have not been fully elucidated. METHODS: A Mendelian randomization (MR) was performed to estimate the causality between two diseases. Bioinformatics tools, including gene ontology and pathway enrichment analyses, were employed to analyze the common differentially expressed genes (DEGs) in periodontitis and T2D. MR and colocalization analyses were then utilized to investigate the causal associations between potential pathogenic gene expression and the risk of T2D. Single cell-type expression analysis was further performed to detect the cellular localization of these genes. RESULTS: Genetically predicted periodontitis was associated with a higher risk of T2D (OR, 1.469; 95% CI, 1.117-1.930; P = 0.006) and insulin resistance (OR 1.034; 95%CI 1.001-1.068; P = 0.041). 79 common DEGs associated with periodontitis and T2D were then identified and demonstrated enrichment mainly in CXC receptor chemokine receptor binding and interleutin-17 signaling pathway. The integration of GWAS with the expression quantitative trait locis of these genes from the peripheral blood genetically prioritized 6 candidate genes, including 2 risk genes (RAP2A, MCUR1) and 4 protective genes (WNK1, NFIX, FOS, PANX1) in periodontitis-related T2D. Enriched in natural killer cells, RAP2A (OR 4.909; 95% CI 1.849-13.039; P = 0.001) demonstrated high risk influence on T2D, and exhibited strong genetic evidence of colocalization (coloc.abf-PPH4 = 0.632). CONCLUSIONS: This study used a multi-omics integration method to explore causality between periodontitis and T2D, and revealed molecular mechanisms using bioinformatics tools. Periodontitis was associated with a higher risk of T2D. MCUR1, RAP2A, FOS, PANX1, NFIX and WNK1 may play important roles in the pathogenesis of periodontitis-related T2D, shedding light on the development of potential drug targets.

Heterospecific eavesdropping on disturbance cues of a treefrog.

Alarm signals and cues are crucial to animal survival and vary greatly across species. Eavesdropping on heterospecific alarm signals and cues can provide eavesdroppers with information about potential threats. In addition to acoustic alarm signals, evidence has accumulated that chemical alarm cues and disturbance cues can also play a role in alerting conspecifics to potential danger in adult anurans (frogs and toads). However, there is very little known about whether disturbance cues are exploited by heterospecifics. In the present study, we conducted a binary choice experiment and a prey chemical discrimination experiment, respectively, to test the responses of a sympatric anuran species (red webbed treefrogs, Rhacophorus rhodopus) and a sympatric predator species (Chinese green tree vipers, Trimeresurus stejnegeri) to disturbance odors emitted by serrate-legged small treefrogs (Kurixalus odontotarsus). In the binary choice experiment, we found that the presence of disturbance odors did not significantly trigger the avoidance behavior of R. rhodopus. In the prey chemical discrimination experiment, compared with odors from undisturbed K. odontotarsus (control odors) and odorless control, T. stejnegeri showed a significantly higher tongue-flick rate in response to disturbance odors. This result implies that disturbance odor cues of K. odontotarsus can be exploited by eavesdropping predators to detect prey. Our study provides partial evidence for heterospecific eavesdropping on disturbance cues and has an important implication for understanding heterospecific eavesdropping on chemical cues of adult anurans.

Development of a machine learning multiclass screening tool for periodontal health status based on non-clinical parameters and salivary biomarkers.

AIM: To develop a multiclass non-clinical screening tool for periodontal disease and assess its accuracy for differentiating periodontal health, gingivitis and different stages of periodontitis. MATERIALS AND METHODS: A cross-sectional diagnostic study on a convenience sample of 408 consecutive subjects was conducted by applying three non-clinical index tests estimating different features of the periodontal health-disease spectrum: a self-administered questionnaire, an oral rinse activated matrix metalloproteinase-8 (aMMP-8) point-of-care test (POCT) and determination of gingival bleeding on brushing (GBoB). Full-mouth periodontal examination was the reference standard. The periodontal diagnosis was made on the basis of the 2017 classification of periodontal diseases and conditions. Logistic regression and random forest (RF) analyses were performed to predict various periodontal diagnoses, and the accuracy measures were assessed. RESULTS: Four-hundred and eight subjects were enrolled in this study, including those with periodontal health (16.2%), gingivitis (15.2%) and stage I (15.9%), stage II (15.9%), stage III (29.7%) and stage IV (7.1%) periodontitis. Nine predictors, namely 'gum disease' (Q1), 'a rating of gum/teeth health' (Q2), 'tooth cleaning' (Q3a), the symptom of 'loose teeth' (Q4), 'use of floss' (Q7), aMMP-8 POCT, self-reported GBoB, haemoglobin and age, resulted in high levels of accuracy in the RF classifier. High accuracy (area under the ROC curve > 0.94) was observed for the discrimination of three (health, gingivitis and periodontitis) and six classes (health, gingivitis, stages I, II, III and IV periodontitis). Confusion matrices showed that the misclassification of a periodontitis case as health or gingivitis was less than 1%-2%. CONCLUSIONS: Machine learning-based classifiers, such as RF analyses, are promising tools for multiclass assessment of periodontal health and disease in a non-clinical setting. Results need to be externally validated in appropriately sized independent samples (ClinicalTrials.gov NCT03928080).

Association of the number of natural teeth with dietary diversity and nutritional status in older adults: A cross-sectional study in China.

AIM: To investigate the association of the number of natural teeth with overall dietary diversity and nutritional status in a nationally representative study among older adults in China. MATERIALS AND METHODS: A cross-sectional analysis was conducted among community-dwelling adults aged 65 years or older from the Chinese Longitudinal Healthy Longevity Study. According to the self-reported number of natural teeth, participants were categorized into ≥20, 10-19, 1-9 natural teeth, and edentulous. Dietary diversity score (DDS) was constructed based on intake frequencies of 10 food groups assessed by a simplified food frequency questionnaire. The geriatric nutritional risk index was used to measure the malnutrition status (i.e., normal, mild malnutrition, and moderate-to-severe malnutrition) among a subgroup of participants. Linear and multinomial logistic regression models were used to examine the corresponding associations. RESULTS: Among 54,796 study participants, the mean (SD) age was 87.86 (11.45) years, 82.7% had poor dentition (<20 natural teeth), and 27.3% wore dentures. After multivariable adjustment, participants with poor dentition had lower DDSs (ßedentulous  = -0.39, 95% confidence interval [CI], -0.48, -0.30; ß1-9 teeth  = -0.46, 95% CI, -0.55, -0.37; ß10-19 teeth  = -0.36, 95% CI, -0.46, -0.26) than those with 20 natural teeth or more. For individual food items, edentulous, 1-9 and 10-19 natural teeth were associated with lower odds of regular intake of fresh fruits, fresh vegetables, meat, fish and aquatic products, eggs, legumes, preserved vegetables, tea, and garlic, but higher odds of regular intake of sugar and sweets. Among participants with poor dentition, individuals without dentures had lower intake frequencies of most food groups than those wearing dentures. In addition, poor dentition was related to lower odds of normal nutritional status (odds ratio = 0.49, 95% CI, 0.27, 0.89). CONCLUSIONS: Older adults with poor dentition had significantly lower dietary diversity and worse nutritional status. Future studies are warranted to identify effective interventions to improve the dietary quality and nutrition status among partially and fully edentulous individuals, including those with Stage IV periodontitis.

Diagnostic accuracy of active matrix metalloproteinase-8 point-of-care test for the discrimination of periodontal health status: Comparison of saliva and oral rinse samples.

BACKGROUND AND OBJECTIVES: Assessment of biomarkers, specifically active matrix metalloproteinase-8 (aMMP-8), in saliva/oral rinses is a promising diagnostic approach for periodontal health and disease. Different oral fluids have specific advantages and limitations. This study investigates the effect of sampling different fluids on the accuracy of an aMMP-8 point of care test (POCT). METHODS: Unstimulated whole saliva, a first, and a second oral rinse were sequentially taken from 95 consecutive adults. aMMP-8 was quantitatively determined with a lateral flow immunoassay (index test). A full-mouth periodontal examination was used to establish a diagnosis according to the 2017 World Workshop classification of periodontal diseases (reference standard). Diagnostic measures of the area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity were assessed and compared. RESULTS: In all oral fluid samples, periodontitis patients (N = 61) had significantly elevated aMMP-8 levels and increased test positivity rates compared with subjects with periodontal health or gingivitis (N = 34). The intra-individual comparison showed that aMMP-8 levels were significantly higher in 1st oral rinse compared with other samples (1st oral rinse > saliva = 2nd oral rinse, p = .007). The aMMP-8 test using 1st oral rinse exhibited the best accuracy for detecting periodontitis with a sensitivity of 80.3%, a specificity of 67.8% and an AUROC of 0.740. CONCLUSIONS: A 30-second oral rinse with water omitting the prerinse provided the best accuracy to discriminate periodontal health and disease with an aMMP-8 POCT. This regimen seems promising for further studies in large representative populations to verify the current findings.

Food intake, masticatory function, tooth mobility, loss of posterior support, and diminished quality of life are associated with more advanced periodontitis stage diagnosis.

AIM: To describe periodontal and functional characteristics of subjects diagnosed with different stages of periodontitis and to associate measures of masticatory function and quality of life with periodontitis stage. MATERIALS AND METHODS: This was a cross-sectional study on a convenience sample of 214 subjects with periodontitis seeking oral care in a hospital setting. They received a full-mouth intra-oral examination including dental and periodontal charting by a single calibrated examiner who also established the periodontitis stage diagnosis. Subjects were assessed using the OHIP-14, a validated masticatory dysfunction questionnaire, and a quantitative test based on the ability to mix a dual colour chewing gum. Mixing was quantified based on the variance of hue (VOH) with a colorimetric software. Descriptive, univariate, and multivariate analyses were performed. RESULTS: Subjects with stage IV periodontitis reported greater impairment of oral-health-related quality of life, reduced food intake or altered food type intake attributed to difficulties in chewing, objective measures of masticatory dysfunction, tooth loss, as well as more advanced periodontal breakdown compared with subjects with stages I-III of the disease. Quantitative assessment of masticatory function was associated, in a multivariate analysis, with (i) loss of functional tooth units in the premolar/molar region, presence of hypermobile teeth, and severity of periodontal attachment loss, and (ii) age, body mass index, and periodontitis stage IV and grade C diagnosis. CONCLUSIONS: Subjects with stage IV periodontitis are characterized by a specific set of signs and symptoms of advanced periodontal breakdown and functional impairment, which impact on the quality of life and masticatory function/food intake choices. Stage IV periodontitis captures a clinical entity with distinct features and treatment needs. This study is registered in ClinicalTrials.gov (NCT03928080).

Does machine-vision-assisted dynamic navigation improve the accuracy of digitally planned prosthetically guided immediate implant placement? A randomized controlled trial.

OBJECTIVES: This randomized controlled clinical trial was designed to compare the accuracy of machine-vision (MV)-based dynamic navigation (DN)-assisted immediate implant placement with the conventional freehand technique. MATERIAL AND METHODS: A total of 24 subjects requiring immediate implant placement in maxillary anterior teeth were randomly assigned to either the control (freehand by an experienced surgeon, n = 12) or the test group (MV-DN, n = 12). Implant platform, implant apex, angular, and depth deviations with respect to prosthetically guided digital planning and differences in implant insertion torque (ITV) and implant stability quotient (ISQ) were compared between the groups. RESULTS: MV-DN resulted in more accurate immediate implant position: significantly smaller global platform deviation (1.01 ± 0.41 mm vs. 1.51 ± 0.67 mm, p = .038), platform depth deviation (0.44 ± 0.46 mm vs. 0.95 ± 0.68 mm, p = .045), global apex deviation (0.88 ± 0.43 mm vs. 1.94 ± 0.86 mm, p = .001), and lateral apex deviation (0.68 ± 0.30 mm vs. 1.61 ± 0.88 mm, p = .004) were found in MV-DN compared to controls. No significant intergroup differences were observed for ITV and ISQ. CONCLUSIONS: MV-DN achieved more precise immediate implant position and comparable primary stability. Further trials are necessary to assess the benefits in terms of esthetics and tissue health/stability.

Conspecific odor cues induce different vocal responses in serrate-legged small treefrogs, but only in the absence of acoustic signals.

BACKGROUND: Signal detection is crucial to survival and successful reproduction, and animals often modify behavioral decisions based on information they obtained from the social context. Undeniably, the decision-making in male-male competition and female choice of anurans (frogs and toads) depends heavily on acoustic signals. However, increasing empirical evidence suggests that additional or alternative types of cue (e.g., visual, chemical, and vibratory) can be used to detect, discriminate and locate conspecifics in many anuran species. Nevertheless, few studies have investigated whether conspecific odor cues affect male's calling behavior. In this study, we conducted an experiment to investigate whether and how different chemical cues (male odors, female odors, and stress odors) from conspecifics affect male's calling strategies in serrate-legged small treefrogs (Kurixalus odontotarsus), and whether the combined chemical and acoustic stimuli have additive effects on calling behavior or not. RESULTS: We found that compared with female odors, male K. odontotarsus reduced calling investment in response to male odors or stress odors, in the absence of rival's advertisement calls. When odor stimuli and advertisement calls were presented simultaneously, however, there were no differences in the vocal response of focal males among odor groups. CONCLUSIONS: These results provide evidence that male treefrogs switch calling investment according to different odor cues from conspecifics, and further demonstrate that calling behavior can be affected by chemical cues in anuran species. Our study highlights the potential role of airborne chemical cues in sex identification and contributes to increase our understanding of anuran communication.

Multisensory modalities increase working memory for mating signals in a treefrog.

Animal choruses, such as those found in insects and frogs, are often intermittent. Thus, females sampling males in the chorus might have to remember the location of the potential mates' calls during periods of silence. Although a number of studies have shown that frogs use and prefer multimodal mating signals, usually acoustic plus visual, it is not clear why they do so. Here we tested the hypothesis that preference for multimodal signals over unimodal signals might be due to multimodal signals instantiating longer memories than unimodal signals, particularly during the inter-chorus intervals. We tested this hypothesis in serrate-legged small treefrogs Kurixalus odontotarsus whose males produce advertisement calls accompanied by conspicuous vocal sac inflation. Females were tested with acoustic and acoustic + visual (video of inflating-deflating vocal sac) mating calls. We found that females prefer multimodal calls over unimodal, audio-only calls. Furthermore, multimodal calls are still preferred after a silent period of up to 30 s, a time that spans the average silent period of the chorus. This was not true of unimodal calls. Our results demonstrate that a multimodal signal can engage longer working memory than a unimodal signal, and thus female memory might favour the evolution of multimodal signals in males through sexual selection. Selection might also favour female preference for multimodal signals if longer memory facilitates mate searching and assessment. Our study does not allow us to elucidate the sequence of evolution of this trait and preference.

Gingival bleeding on brushing as a sentinel sign of gingival inflammation: A diagnostic accuracy trial for the discrimination of periodontal health and disease.

AIM: To assess the accuracy of self-reported gingival bleeding on brushing (GBoB) for differentiating between periodontal health and disease and explore the optimal haemoglobin concentration that enables visual detection of GBoB. MATERIALS AND METHODS: Self-assessment of GBoB was conducted in supervised sessions for 408 consecutive adults. The haemoglobin levels in saliva/toothpaste slurry (TPS) were analysed, followed by a full-mouth periodontal examination. Periodontal diagnoses were made based on the 2017 classification of periodontal diseases. Gingival inflammation was defined as presence of at least 10% of sites with bleeding on probing (BOP). Logistic regression and area under the receiver operating characteristic curve (AUROC) analyses were applied to assess the accuracy of GBoB. RESULTS: Overall, 37.1% of the subjects claimed self-reported GBoB, and they had higher values of BOP (median: 25.0%; interquartile range (IQR): 16.0%-37.5%) than those without GBoB (median: 13.5%; IQR: 8.0%-24.8%, p < .001). The concentration/total amount of haemoglobin in TPS was positively correlated with the number of bleeding sites (r = .409/r = .520, p < .001). Haemoglobin concentration of 90.58 µg/ml or 0.51 µl blood volume enabled visual detection of GBoB with an AUROC of 0.848. Self-reported GBoB exhibited significantly increased values of diagnostic odds ratios (3-8) for varying degrees of gingival inflammation and periodontal disease (gingivitis and periodontitis). It showed low to moderate accuracy for discriminating periodontitis and gingivitis from periodontal health, with a sensitivity of 37.1% and 61.3% and a specificity of 84.8% and 84.4%, respectively. Absence of self-reported GBoB and low levels of haemoglobin had 93%-98% predictive values for periodontal health. CONCLUSIONS: Despite its low sensitivity for the discrimination of periodontitis, self-reported GBoB is a promising sentinel sign for periodontal health and disease, and gingival inflammation in particular. It is visually detectable after minor blood loss. After validation in an independent population, identification of GBoB may promote earlier detection and better prevention and treatment of periodontal disease, thereby eventually reducing the global burden of the disease.

Diagnostic accuracy of self-reported measures of periodontal disease: A clinical validation study using the 2017 case definitions.

AIM: To clinically validate a self-reported questionnaire for periodontal disease and assess its accuracy for differentiating periodontal health and different stages of periodontitis. METHODS: A Chinese (Cantonese) version of a self-reported questionnaire was prepared by translating and validating the original English questions proposed by the Centers for Disease Control and Prevention/American Academy of Periodontology (CDC/AAP). The utility of the CDC/AAP questionnaire and its individual questions was assessed against a full-mouth periodontal examination. Periodontal case definition was based on the 2017 World Workshop classification of periodontal diseases. Multivariable logistic regression and the area under the receiver operating characteristic curve (AUROC) analysis were performed to assess the accuracy of the questionnaire. RESULTS: 408 subjects enrolled in this study, including those with periodontal health (16.2%), gingivitis (15.2%), Stages I/II periodontitis (31.8%) and Stages III/IV periodontitis (36.8%). Overall, the questionnaire had poor accuracy in detecting the presence of Stages I/II periodontitis with an AUROC 0.608. While it showed moderate to high accuracy for identifying periodontal disease (gingivitis and periodontitis), periodontitis and Stages III/IV periodontitis with an AUROC of 0.837, 0.803 and 0.870, respectively. Self-reported measures in combination with age and tobacco smoking showed excellent performance for identifying Stages III/IV periodontitis with a high AUROC of 0.953, a sensitivity of 95.7%, and a specificity of 89.0%. Specific questions and combinations provided greater utility to discriminate the various periodontal case definitions. CONCLUSIONS: The self-reported CDC/AAP questionnaire may be a feasible tool for detecting periodontitis, and its combination with demographic and lifestyle factors is useful for the identification of individuals with Stages III/IV periodontitis. This questionnaire seems less helpful in screening of Stages I/II periodontitis. Further studies are needed to test the validity in larger community-based populations.

Diagnostic accuracy of a point-of-care aMMP-8 test in the discrimination of periodontal health and disease.

AIM: To assess the diagnostic utility of an oral rinse active matrix metalloproteinase-8 (aMMP-8) point-of-care test (POCT) for differentiating periodontal health, gingivitis, as well as different stages and grades of periodontitis. MATERIALS & METHODS: The aMMP-8 index test was undertaken in 408 consecutive adults, followed by a full-mouth periodontal examination. The reference standard was the 2017 World Workshop classification of periodontal diseases. Sensitivity, specificity, and the area under the receiver operating characteristic curve (AUROC) were assessed. RESULTS: 68.6% of the participants were diagnosed with periodontitis, including Stages I (15.9%), II (15.9%), III (29.7%) and IV (7.1%). A positive aMMP-8 POCT was associated with periodontitis after adjusting for age, gender, tobacco smoking and systemic diseases, while it was unable to differentiate among the stages/grades of periodontitis and between gingivitis/periodontal health. This test showed a sensitivity of 33.2% and a specificity of 93.0% for detecting periodontitis (threshold level >10 ng/ml). The levels of aMMP-8 adjusted by the number of teeth present (aMMP-8/NTP) performed better for periodontitis (sensitivity: 67.1%; specificity: 68.8%). Notably, aMMP-8/NTP were strongly predictive for Stage IV periodontitis (threshold level =0.4312 ng/ml) (sensitivity: 89.7%; specificity: 73.6%; and AUROC: 0.856). The test performance greatly improved in combination with age and smoking, with a sensitivity of 82.5%, a specificity of 84.4%, and an AUROC of 0.883. CONCLUSION: This aMMP-8 POCT is able to detect periodontitis with better specificity than sensitivity across the spectrum of its severity. This test may be useful for periodontal screening in conjunction with subject characteristics and/or other sensitive screening tools. Further validation studies are needed.

Autologous connective tissue graft or xenogenic collagen matrix with coronally advanced flaps for coverage of multiple adjacent gingival recession. 36-month follow-up of a randomized multicentre trial.

AIM: To report the 36-month follow-up of a trial comparing the adjunct of a xenogenic collagen matrix (CMX) or connective tissue graft (CTG) to coronally advanced flaps (CAF) for coverage of multiple adjacent recessions. MATERIAL AND METHODS: 125 subjects (61 CMX) with 307 recessions in 8 centres from the parent trial were followed-up for 36 months. Primary outcome was change in position of the gingival margin. Multilevel analysis used centre, subject and tooth as levels and baseline parameters as covariates. RESULTS: No differences were observed between the randomized and the follow-up population. Average baseline recession was 2.6 ± 1.0 mm. 3-year root coverage was 1.5 ± 1.5 mm for CMX and 2.0 ± 1.0 mm for CTG (difference of 0.32 mm, 95% CI from -0.02 to 0.65 mm). The upper limit of the confidence interval was over the non-inferiority margin of 0.25 mm. No treatment differences in position of the gingival margin were observed between 6- and 36-month follow-up (difference 0.06 mm, 95% CI -0.17 to 0.29 mm). CONCLUSION: CMX was not non-inferior with respect to CTG in multiple adjacent recessions. No differences in stability of root coverage were observed between groups and in changes from 6 to 36 months. Previously reported shorter time to recovery, lower morbidity and more natural appearance of tissue texture and contour observed for CMX in this trial are also relevant in clinical decision-making.

Prevalence and morphological characteristics of disto-lingual roots in mandibular first molars: a cone beam CT study with diagnostic and therapeutic implications.

OBJECTIVES: High prevalence of disto-lingual roots (DLR) at the mandibular molar in Chinese can complicate the management of periodontitis. This study assessed the prevalence and morphological features of mandibular first molar DLR and furcation entrances in a Hong Kong population by analysis of cone beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT including the mandibular 1st molar region were identified from the Prince Philip Dental Hospital archive and analyzed by a single investigator. Morphologic features and location of DLR were studied and presented as 95% confidence intervals. RESULTS: A total of 398 CBCTs with 716 mandibular first molars were analyzed. The prevalence of DLRs in mandibular first molars on subject based was 20.1% (95% C.I. 16.2-24%). DLR was located 44.5° ± 8.9° (95% C.I. 42.8-46.1°) to the mid-lingual of the mandibular first molar, with a bucco-lingual width 3.3 mm ± 0.5 mm (95% C.I. 3.2-3.4 mm). The mesial furcation entrance was located 4.0 mm ± 0.9 mm (95% C.I. 3.8-4.2 mm) apical to the cemento-enamel junction (CEJ) while the distal was 5.2 mm ± 1.3 mm (95% C.I. 5.0-5.4 mm) from the CEJ. The surface area of the DLR was 106.9 mm2 ± 41.2 mm2 (95% C.I. 98.9-114.8 mm2). CONCLUSIONS: Chinese population has a high prevalence of DLRs. The present information is critical for understanding the morphological features of DLR and guide diagnosis and treatment of stage III periodontitis as well as for secondary prevention and supportive care of stage II periodontitis. CLINICAL RELEVANCE: Little is known about the location and morphology of disto-lingual roots of mandibular 1st molars, yet they are frequently present in patients with Chinese ethnic background, thus complicating diagnosis and treatment. The present study utilized CBCT to analyze the prevalence and morphological features of the mandibular first molar DLR and furcation entrance. It is the first study reporting on the position of the DLR, degree of separation of the furcation, and the surface area of the DLR.

Nasal and Oral Subunits Reconstruction of Localized Scleroderma Deformities.

ABSTRACT: Localized scleroderma is a rare soft tissue disorder characterized by a thickening of the skin from excessive collagen deposits. For patients with face involved, soft tissue depression and atrophy could cause serious facial contour deformity and adversely affect the patients' quality of social life. However, localized scleroderma cases with delicate facial aesthetic subunits defects were rarely reported to be surgically reconstructed. In this study, we present 2 patients with nasal subunits and oral subunit deformities caused by localized scleroderma respectively. The first patient with a right-side alar defect and nasal dorsum depression, forehead depression and eyebrow depression were treated through a 2-stage surgical approach, with microvascular preauricular and helical rim flap and dermofat graft transplantation. The lower lip and mandible defects of the second patient were reconstructed with a combination of submental flap and fat grafting. The transplanted dermofat graft, fat graft, the microvascular free flap, and the submental flap survived completely and maintained adequate tissue volume and facial contour during the follow-up time of 2 years. Both patients were satisfied with the overall aesthetic results. This clinical report supports the use of microsurgical flap and tissue grafts on the treatment of localized scleroderma (LS) caused facial aesthetic subunits deformities.

Male serrate-legged treefrogs adjust competition strategies according to visual or chemical cues from females.

There is increasing evidence that many anurans use multimodal cues to detect, discriminate and/or locate conspecifics and thus modify their behaviors. To date, however, most studies have focused on the roles of multimodal cues in female choice or male-male interactions. In the present study, we conducted an experiment to investigate whether male serrate-legged small treefrogs (Kurixalus odontotarsus) used visual or chemical cues to detect females and thus altered their competition strategies in different calling contexts. Three acoustic stimuli (advertisement calls, aggressive calls and compound calls) were broadcast in a randomized order after a spontaneous period to focal males in one of four treatment groups: combined visual and chemical cues of a female, only chemical cues, only visual cues and a control (with no females). We recorded the vocal responses of the focal males during each 3 min period. Our results demonstrate that males reduce the total number of calls in response to the presence of females, regardless of how they perceived the females. In response to advertisement calls and compound calls, males that perceived females through chemical cues produced relatively fewer advertisement calls but more aggressive calls. In addition, they produced relatively more aggressive calls during the playback of aggressive calls. Taken together, our study suggests that male Kodontotarsus adjust their competition strategies according to the visual or chemical cues of potential mates and highlights the important role of multisensory cues in male frogs' perception of females.

Self-reported bleeding on brushing as a predictor of bleeding on probing: Early observations from the deployment of an internet of things network of intelligent power-driven toothbrushes in a supportive periodontal care population.

BACKGROUND: Bleeding on brushing (BoB) is an important sign of gingival inflammation. Recently, the use of intelligent toothbrushes and oral health Apps has shown potential to improve oral and periodontal health. In the context of the introduction of an Internet of things network of intelligent power-driven toothbrushes in a supportive periodontal care programme, the aim of this study was (a) to audit the adoption and retention of this new technology; and (b) to preliminarily assess the feasibility to gather data on BoB and associate them with clinical periodontal parameters. METHODS: 100 subjects with different periodontal case diagnoses participating in supportive periodontal care (SPC) were provided with and instructed on the use of an intelligent power-driven toothbrush connected with an App (I-Brush). Brushing sessions and occurrence of BoB were recorded through the App and stored in a data protection compliant backend. Subject retention was audited over time. BoB recorded in the two weeks before the SPC appointment was associated with clinical parameters observed by the clinician blind to App data. RESULTS: 75% of subjects provided data from using the power toothbrush and the App for a minimum of 10 brushing sessions over an average period of 362 days. Compared with baseline, subjects' oral hygiene, bleeding on probing and prevalence of residual pockets improved gradually while using the I-Brush. The number of BoB episodes in the two weeks leading to the SPC appointment and the number of residual pockets predicted BOP (p < .001) detected during the examination. App use in the previous two weeks was associated with lower plaque scores at SPC. CONCLUSIONS: These preliminary observations indicate good adoption and retention of a mobile health system built around an intelligent power toothbrush in a SPC population. The App was able to gather clinically relevant information predicting the observed degree of gingival inflammation. Deployment of mHealth systems seems feasible in dental practice and may bring significant oral health benefits. More investigations are needed in this area.

[Numerical study on the performance effect of the ratio of long axis to short axis of upright polypropylene infusion bag].

The study aims to investigate the effect of the ratio of long axis to short axis (RLS) of upright polypropylene infusion bag on discharging process and to search the best RLS. Aiming at five different RLS (1. 5 : 1, 2 : 1, 3 : 1, 4 : 1 and 5 : 1, respectively) with the volume of 100 mL, 250 mL and 500 mL, respectively, based on finite element method, analyzing the variation of stress distribution, emptying rate, drugging space and steadiness coefficient, etc. For the bags of the same volume, emptying rate increased with increasing of RLS, but the steadiness coefficient decreased with increasing of RLS. The specific increasing amplitude of emptying rate and decreasing range of steadiness coefficient were as follows: 20% and 49% for 100 mL infusion bag, 9% and 51% for 250 mL infusion bag, and 11% and 46% for 500 mL infusion bag, respectibvely, when RLS increased from 1. 5 : 1 to 5 : 1. Comparatively speaking, the increasing amplitude of the emptying rate is remarkably less than the decreasing range of the steadiness coefficient. By comprehensive consideration of both emptying rate and steadiness coefficient, lower RLS is recommended for upright polypropylene infusion bag.