Motivational interviewing for caries prevention in adolescents: a randomized controlled trial.

OBJECTIVE: The objective of this study is to investigate the effectiveness of motivational interviewing (MI) in changing health behaviors (snack and toothbrushing) and preventing dental caries among adolescents. METHODS: Five hundred and twelve adolescents with unfavorable caries-related behaviors ("snacking three times or more a day" and/or "toothbrushing less often than twice a day") were randomly assigned to three groups. Group I received prevailing health education (oral health talks and pamphlets). Participants in group II joined a one-on-one face-to-face MI session. In group III, a patient communication tool (Cariogram) was incorporated to facilitate the MI process. At baseline and 24 months post-intervention, a self-administered questionnaire gathered information of participants' sociodemographic characteristics and oral health self-efficacy and behaviors. Their oral hygiene and tooth status were assessed by a blinded examiner. RESULTS: After 24 months, 460 (89.8%) participants were followed up. Compared with group I, (i) restriction of frequent snacking was more likely in group II [OR (95% CI): 3.91 (1.48-10.33)] and group III [OR (95% CI): 6.33 (2.46-16.27)], whereas group III tended to adopt the behavior of toothbrushing twice a day [OR (95% CI): 4.80 (1.79-12.85)]; (ii) no significant between-group difference in plaque score reduction was found (p > 0.05); and (iii) groups II and III developed fewer cavitated teeth (△DICDASII 3-6MFT) [ß (95% CI): - 0.19 (- 0.37, - 0.01) and - 0.20 (- 0.38, - 0.02), respectively], whereas increment of total carious lesions (△DICDASII 1-6MFT) was lower in group III [ß (95% CI): - 0.63 (- 1.24, - 0.02)]. CONCLUSION: MI outperformed prevailing health education in improving oral health behaviors and preventing dental caries among adolescents. CLINICAL RELEVANCE: Incorporating MI into dental care for caries-prone adolescents contributes to optimal health outcomes. TRIAL REGISTRATION: HKUCTR-1852 ( http://www.hkuctr.com/ ) (Hong Kong, 2013).

The effect of systemic antibiotics on clinical and patient-reported outcome measures of oral implant therapy with simultaneous guided bone regeneration.

OBJECTIVES: The aim of the present superiority study was to determine the effect of systemic antibiotics primarily on patient-reported outcome measures (PROMs) and post-surgical complications in patients undergoing oral implant therapy with simultaneous guided bone regeneration (GBR). MATERIALS AND METHODS: A total of 236 medically and periodontally healthy patients received oral implants with simultaneous GBR at seven centres. Pre-operative antibiotics of 2 g amoxicillin were prescribed to the test group 1 hr prior to surgery and 500 mg thrice daily on days 1-3 after surgery. The control group was given a placebo. Group allocation was performed randomly. Primary outcome variables were PROMs recorded as visual analogue scale scores assessed on days 1-7 and 14 on pain, swelling, haematoma and bleeding. Post-operative complications as secondary outcome variables were examined at 1, 2, 4 and 12 weeks from surgery. Chi-square tests and repeated measures of analysis of variance (ANOVA) were performed for statistical evaluation. RESULTS: No statistically significant differences (p > .05) between the two groups were detected for the evaluated PROMs. The same was noted with respect to post-surgical complications. Four implants were lost-three in the test group and one in the control group. CONCLUSION: In this trial, systemic antibiotics did not provide additional benefits to PROMs, nor the prevention of post-surgical complications in medically and periodontally healthy patients undergoing oral implant therapy with simultaneous GBR. However, further studies with larger sample sizes are still required to support the clinical outcomes of this study.

Longitudinal measurement invariance and explanatory IRT models for adolescents' oral health-related quality of life.

BACKGROUND: Longitudinal invariance is a perquisite for a valid comparison of oral health-related quality of life (OHRQoL) scores over time. Item response theory (IRT) models can assess measurement invariance and allow better estimation of the associations between predictors and latent construct. By extending IRT models, this study aimed to investigate the longitudinal invariance of the two 8-item short forms of the Child Perception Questionnaire (CPQ11-14) regression short form (RSF:8) and item-impact short form (ISF:8) and identify factors associated with adolescents' OHRQoL and its change. METHODS: All students from S1 and S2 (equivalent to US grades 6 and 7) who were born in April 1997 and May 1997 (at age 12) from 45 randomly selected secondary schools were invited to participate in this study and followed up after 3 years. Data on the CPQ11-14 RSF:8 and CPQ11-14 ISF:8, demographics, oral health behavior and status were collected. Explanatory graded response models were fitted to both short forms of the CPQ11-14 data for assessing longitudinal invariance and factors associated with OHRQoL. The Bayesian estimation method - Monte Carlo Markov Chain (MCMC) with Gibbs sampling was adopted for parameter estimation and the credible intervals were used for inference. RESULTS: Data from 649 children at age 12 at baseline and 415 children at age 15 at follow up were analyzed. For the 12 years old children, healthier oral health behavior, better gum status, families with both parents employed and parents' education level were found to be associated with better OHRQoL. Four items among the 2 short forms lacked longitudinal invariance. With statistical adjustment of longitudinal invariance, OHRQoL were found improved in general over the 3 years but no predictor was associated with OHRQoL in follow-up. For those with decreased family income, their OHRQoL had worsened over 3 years. CONCLUSIONS: IRT explanatory analysis enables a more valid identification of the factors associated with OHRQoL and its changes over time. It provides important information to oral healthcare researchers and policymakers.

Evaluation of psychometric properties and differential item functioning of 8-item Child Perceptions Questionnaires using item response theory.

BACKGROUND: Four-factor structure of the two 8-item short forms of Child Perceptions Questionnaire CPQ11-14 (RSF:8 and ISF:8) has been confirmed. However, the sum scores are typically reported in practice as a proxy of Oral health-related Quality of Life (OHRQoL), which implied a unidimensional structure. This study first assessed the unidimensionality of 8-item short forms of CPQ11-14. Item response theory (IRT) was employed to offer an alternative and complementary approach of validation and to overcome the limitations of classical test theory assumptions. METHODS: A random sample of 649 12-year-old school children in Hong Kong was analyzed. Unidimensionality of the scale was tested by confirmatory factor analysis (CFA), principle component analysis (PCA) and local dependency (LD) statistic. Graded response model was fitted to the data. Contribution of each item to the scale was assessed by item information function (IIF). Reliability of the scale was assessed by test information function (TIF). Differential item functioning (DIF) across gender was identified by Wald test and expected score functions. RESULTS: Both CPQ11-14 RSF:8 and ISF:8 did not deviate much from the unidimensionality assumption. Results from CFA indicated acceptable fit of the one-factor model. PCA indicated that the first principle component explained >30 % of the total variation with high factor loadings for both RSF:8 and ISF:8. Almost all LD statistic <10 indicated the absence of local dependency. Flat and low IIFs were observed in the oral symptoms items suggesting little contribution of information to the scale and item removal caused little practical impact. Comparing the TIFs, RSF:8 showed slightly better information than ISF:8. In addition to oral symptoms items, the item "Concerned with what other people think" demonstrated a uniform DIF (p < 0.001). The expected score functions were not much different between boys and girls. CONCLUSIONS: Items related to oral symptoms were not informative to OHRQoL and deletion of these items is suggested. The impact of DIF across gender on the overall score was minimal. CPQ11-14 RSF:8 performed slightly better than ISF:8 in measurement precision. The 6-item short forms suggested by IRT validation should be further investigated to ensure their robustness, responsiveness and discriminative performance.

Effect of systemic antibiotics on clinical and patient-reported outcomes of implant therapy - a multicenter randomized controlled clinical trial.

OBJECTIVES: To determine the effect of various systemic antibiotic prophylaxis regimes on patient-reported outcomes and postsurgical complications in patients undergoing conventional implant installation. MATERIAL AND METHODS: Three hundred and twenty-nine healthy adults in need of conventional implant installation were randomly assigned to one of four groups: (i) preoperatively 2 g of amoxycillin 1 h before surgery (positive control, PC), (ii) postoperatively 2 g of amoxycillin immediately following surgery (test 1, T1), (iii) preoperatively 2 g of amoxycillin 1 h before and 500 mg thrice daily on days 2 and 3 after surgery (test 2, T2), (iv) preoperatively 2 g of placebo 1 h before surgery (negative control, NC). Subjects were examined clinically by blinded examiners over 8 weeks after implant installation. In addition, Visual Analogue Scales (VAS) for pain, swelling, bruising and bleeding were obtained over 14 days. ANOVA was performed for the VAS. Chi-square tests were applied for postsurgical complications. RESULTS: All VAS scores were low for all groups and decreased over time (P < 0.001). There were no significant differences for the VAS scores between the various groups at any time point (P > 0.05). There was only a significant difference in flap closure at week 4, where NC had 5% of the subjects not achieving complete wound closure compared to 0% for the three other groups (P = 0.01), with no other significant differences for any postsurgical complications (P > 0.05). CONCLUSION: For standard single implant placement, prophylactic systemic antibiotics either before or after, or before and after the surgical procedure do not improve patient-reported outcomes or prevalence of postsurgical complications.

Treatment seeking behaviour in southern Chinese elders with chronic orofacial pain: a qualitative study.

BACKGROUND: Chronic orofacial pain (OFP) is common in general adult populations worldwide. High levels of psychological distress and impaired coping abilities are common among Western people with chronic OFP but limited information was found in southern Chinese people. This study aimed to explore the perceptions and experiences of community dwelling elderly people with chronic OFP symptoms and their treatment seeking behaviour in Hong Kong. METHODS: An exploratory qualitative interview study was conducted. Elderly people experiencing chronic OFP symptoms were invited to take part in an individual semi-structured interview. A total of 25 semi-structured interviews were performed for 25 participants. RESULTS: Pertinent issues relating to the treatment seeking behaviour emerged from the interviews, many of which were inter-related and overlapping. They were organized into three major themes: (i) Impact of chronic OFP on daily life; (ii) Personal knowledge and feeling of chronic OFP; (iii) Management of chronic OFP. The participants were found to have the intention to seek professional treatment, but there were barriers which discouraged them continuing to seek professional treatment. They also received complementary treatment for chronic OFP, such as acupuncture, massage and "chi kung". Moreover, a wide range self-management techniques were also mentioned. On the other hand, those who did not seek professional treatment for the chronic OFP claimed that they had accepted or adapted to the pain as part of their lives. CONCLUSIONS: This qualitative study observed that elderly people affected by chronic OFP symptoms in Hong Kong sought many different ways to manage their pain including traditional and complementary approaches. The role of the dentist in dealing with chronic OFP is unclear. Multiple barriers exist to accessing care for chronic OFP. The findings may be used to inform future chronic OFP management strategies in Hong Kong.

A quantitative comparison of bone resection margin distances in virtual surgical planning versus histopathology: a prospective study.

BACKGROUND: Positive bone margins have been shown to be associated with worse locoregional control and survival performance in oral oncology patients. With the application of computer-assisted surgery and patient-specific surgical guides, the authors can accurately execute the preoperative osteotomy plan. However, how well the authors can predict the margin distance in the final histopathology with a preoperative computed tomography (CT) scan, the factors associated with it, and how much leeway CT should spare when designing the osteotomy planes during virtual surgical planning (VSP) remain to be investigated. MATERIALS AND METHODS: Patients from January 2021 to December 2022 with benign or malignant jaw tumors and with signs of bone marrow involvement in the preoperative CT scan in our center were prospectively recruited to the study. VSP and measurement of the closest margin distance in the CT scan were performed by the single team of surgeons. The resection specimen was processed, and the margin distances were measured by a dedicated senior pathologist with the knowledge of orientation of the osteotomy planes. RESULTS: A total of 35 patients were recruited, with 21 malignant and 14 benign cases. Sixty-eight bone margins were quantitatively analyzed. No significant difference in margin distances measured from the CT scan and final histopathology was detected ( P =0.19), and there was a strong correlation between the two (r s =0.74, P <0.01). A considerable amount of variance was detected in the level of discrepancy between margin distances measured in the CT scan and final histopathology (overall SD=6.26 mm, malignancy SD=7.44 mm, benign SD=4.40 mm). No significant correlation existed between the two margin distances when only maxilla tumor margins were assessed ( P =0.16). CONCLUSION: The bone margin distance in VSP is reliably correlated to the final pathological margin distance. A leeway distance of 15mm and 9mm should be considered when designing the osteotomy planes for malignancy and benign cases, respectively. Extra attention should be paid to maxilla cases when predetermining the osteotomy planes during VSP.

Operationalisation of Successful Ageing in the Oral Health Context: A Citation Analysis.

OBJECTIVES: The rapidly ageing world has placed considerable demands on health and social care. To address this, the World Health Organization (WHO) and United Nations (UN) have declared action for this decade (2021-2030) to promote healthy ageing. Operationalisation of successful ageing in the oral health context in terms of its dimensions and their interconnectedness was determined. METHODS: A citation analysis was conducted following a scoping review to determine oral health's relationship with 5 key dimensions of successful ageing. This included examining the occurrence and co-occurrence amongst dimensions and over time. Specific consideration of citations by country, journal type, and authors through overlay visualisation was performed to map their interconnectedness. RESULTS: The scoping review identified 263 publications covering 1730 specific terms. There was a growing interest in successful ageing in the oral health context, mostly in the past decade (2010 onwards; 65.8%, 173 publications). The dimension of key consideration was "health and ADLs" (activities of daily living); this dimension appeared in 97.3% of publications (n = 256) and was found earliest to emerge, with the greatest link strengths compared to other dimensions. Country-level variations in citation data were observed, and there was good citation interconnectedness between them. Key oracles for dissemination have been medical rather than dental-specific journals. Amongst authors, there was considerable interconnectedness in the field. CONCLUSIONS: Findings highlight how successful ageing in the oral health context has been studied, with implications for addressing the significance of oral health to older peoples' lives in line with the WHO and UN's agenda. Citation analyses identified the "known unknowns" area for further consideration, and these findings have the potential to inform how dental research may best move forward with the successful ageing agenda to bring about translational impact.

Long-term stability of jaw reconstruction with microvascular bone flaps: A prospective longitudinal study.

OBJECTIVES: Microvascular bone flap jaw reconstruction has achieved satisfactory clinical outcomes. However, little is known about the long-term stability of the reconstructed jaw. This prospective longitudinal study aimed to investigate the long-term stability of jaw reconstruction and factors that were associated with it. METHODS: Patients with successful computer-assisted osseous free-flap jaw reconstruction in the Department of Oral and Maxillofacial Surgery, Queen Mary Hospital, Hong Kong were recruited for this prospective longitudinal study. The three-dimensional jaw models at the pre-operative plan, post-operative 1-month, and 2 years were aligned and compared. RESULTS: A total of 69 patients were recruited, among which 48 patients were available for the long-term analysis. Compared to 1-month after surgery, further deviation from the pre-operative plan was observed at post-operative 2 years. Lack of accuracy in surgery, segmental mandible resection especially with the involvement of mandible angles, and post-operative radiation therapy were identified as the significant factors affecting the positional stability of the reconstructed jaw (p < 0.05). Stable reconstruction was observed in the subgroup analysis of patients without post-operative radiation therapy. CONCLUSION: Up to the best of our knowledge, this is the first prospective longitudinal study reporting the long-term stability of jaw reconstruction and its affecting factors. Our data demonstrated that the reconstructed jaw position lacked stability over the postoperative period. How to improve long-term stability of reconstructed jaw thus optimize the functional outcomes warrants further studies.

Relationship between children's oral health-related behaviors and their caregiver's sense of coherence.

BACKGROUND: Sense of coherence (SOC) is hypothesized to be an important psychological factor that enables people to cope with stressors and successfully maintain and improve health. Mother's SOC has been shown to be an important psychological factor associated with oral health and oral health-related behaviors of adolescents and 11- to 12-year-old children. However, little is known about the relationship between the caregiver's SOC and oral health-related behaviors of the preschool children. The objective of this study was to investigate the relationship between oral health-related behaviors of 5-year-old children in Southern China and SOC of their caregiver. METHODS: A cross-sectional study was conducted in a randomized sample of 1332 children aged 5 years and their caregivers in Guangzhou, Southern China. Data were collected through questionnaires completed by the caregivers. The Chinese short version of Antonovsky's SOC scale (13 items) was employed to assess the caregiver's SOC. The outcome variables were the child's oral health-related behaviors, including frequency of sugary snack intake, toothbrushing frequency, utilization of dental service, and pattern of dental visits. Multiple logistic regression was used to analyze the relationship between the variables. RESULTS: No association was found between the children's sugary snack intake and the mother's or the father's SOC. After adjustment for other significant factors related to the child's oral health-related behaviors, 8.9% of the children whose grandparents (as caregivers) had higher SOC scores had a lower frequency of sugary snack intake, compared with the children whose grandparents had lower SOC scores (OR = 0.61, 95% CI = 0.50-0.73, p = 0.008). The other measures of oral health-related behaviors of the child were not significantly associated with the caregiver's SOC. CONCLUSION: Sugary snack intake behavior of the 5-year-old children was not associated with the mother's or the father's SOC. It was associated with the SOC of their grandparents, who are a small group of the caregivers in China.

A systematic review of post-extractional alveolar hard and soft tissue dimensional changes in humans.

BACKGROUND: Removal of teeth results in both horizontal and vertical changes of hard and soft tissue dimensions. The magnitude of these changes is important for decision-making and comprehensive treatment planning, with provisions for possible solutions to expected complications during prosthetic rehabilitation. OBJECTIVES: To review all English dental literature to assess the magnitude of dimensional changes of both the hard and soft tissues of the alveolar ridge up to 12 months following tooth extraction in humans. METHODS: An electronic MEDLINE and CENTRAL search complemented by manual searching was conducted to identify randomized controlled clinical trials and prospective cohort studies on hard and soft tissue dimensional changes after tooth extraction. Only studies reporting on undisturbed post-extraction dimensional changes relative to a fixed reference point over a clearly stated time period were included. Assessment of the identified studies and data extraction was performed independently by two reviewers. Data collected were reported by descriptive methods. Weighted means and percentages of the dimensional changes over time were calculated where appropriate. RESULTS: The search provided 3954 titles and 238 abstracts. Full text analysis was performed for 104 articles resulting in 20 studies that met the inclusion criteria. In human hard tissue, horizontal dimensional reduction (3.79 ± 0.23 mm) was more than vertical reduction (1.24 ± 0.11 mm on buccal, 0.84 ± 0.62 mm on mesial and 0.80 ± 0.71 mm on distal sites) at 6 months. Percentage vertical dimensional change was 11-22% at 6 months. Percentage horizontal dimensional change was 32% at 3 months, and 29-63% at 6-7 months. Soft tissue changes demonstrated 0.4-0.5 mm gain of thickness at 6 months on the buccal and lingual aspects. Horizontal dimensional changes of hard and soft tissue (loss of 0.1-6.1 mm) was more substantial than vertical change (loss 0.9 mm to gain 0.4 mm) during observation periods of up to 12 months, when study casts were utilized as a means of documenting the changes. CONCLUSIONS: Human re-entry studies showed horizontal bone loss of 29-63% and vertical bone loss of 11-22% after 6 months following tooth extraction. These studies demonstrated rapid reductions in the first 3-6 months that was followed by gradual reductions in dimensions thereafter.

A systematic review on survival and success rates of implants placed immediately into fresh extraction sockets after at least 1 year.

BACKGROUND: Type I immediate implant placement has gained popularity because it may reduce treatment time, number of surgeries and post-extraction bone loss. However, this is potentially challenged by inadequate keratinized mucosa for flap adaptation and difficulties in achieving primary stability. Moreover, it has been proven that post-extraction bone loss is an inevitable biological process, which affects treatment outcomes. OBJECTIVES: To estimate survival and success rates of implants and the implant-supported prostheses, the prevalence of biological, technical and aesthetic complications, and the magnitude of soft and hard tissue changes following implant placement immediately into fresh extraction sockets. MATERIAL AND METHODS: An electronic search in MEDLINE (PubMed) and the Cochrane Library from 1991 to July 2010 was performed to include prospective studies on immediate implants with a mean follow-up time of at least 1 year. The survival rates were computed using the STATA statistical software. Weighted means of soft and hard tissue changes were obtained by the inverse variance method. RESULTS: A total of 46 prospective studies, with a mean follow-up time of 2.08 years, were included. The annual failure rate of immediate implants was 0.82% (95% CI: 0.48-1.39%), translating into the 2-year survival rate of 98.4% (97.3-99%). Among the five factors analysed (reasons for extraction, antibiotic use, position of implant [anterior vs. posterior, maxilla vs. mandible), type of loading], only the regimen of antibiotic use affected the survival rate significantly. Lower failure rates were found in groups that were provided with a course of post-operative antibiotics. The success of implant therapy was difficult to assess due to scarce reporting on biological, technical and aesthetic complications. Soft tissue changes occurred mostly in the first 3 months after the provision of restoration, and then stabilized towards end of the first year. Marginal bone loss predominantly took place in the first year after implant placement, with a magnitude generally less than 1 mm. Controversy on hard tissue preservation with platform-switching technique remained unsolved. CONCLUSIONS: Despite the high survival rate observed, more long-term studies are necessary to determine the success of implant treatment provided immediately after tooth extraction. Special attention has to be given to aesthetic outcomes.

Analysis of multilevel grouped survival data with time-varying regression coefficients.

Correlated or multilevel grouped survival data are common in medical and dental research. Two common approaches to analyze such data are the marginal and the random-effects approaches. Models and methods in the literature generally assume that the treatment effect is constant over time. A researcher may be interested in studying whether the treatment effects in a clinical trial vary over time, say fade out gradually. This is of particular clinical value when studying the long-term effect of a treatment. This paper proposed to extend the random effects grouped proportional hazards models by incorporating the possibly time-varying covariate effects into the model in terms of a state-space formulation. The proposed model is very flexible and the estimation can be performed using the MCMC approach with non-informative priors in the Bayesian framework. The method is applied to a data set from a prospective clinical trial investigating the effectiveness of silver diamine fluoride (SDF) and sodium fluoride (NaF) varnish in arresting active dentin caries in the Chinese preschool children. It is shown that the treatment groups with caries removal prior to the topical fluoride applications are most effective in shortening the arrest times in the first 6-month interval, but their effects fade out rapidly since then. The effects of treatment groups without caries removal prior to topical fluoride application drop at a very slow rate and can be considered as more or less constant over time. The applications of SDF solution is found to be more effective than the applications of NaF vanish.

Investigation of factors associated with treatment-seeking in Southern Chinese with orofacial pain.

AIMS: To investigate key factors associated with treatment-seeking for orofacial pain symptoms in community-dwelling adult Chinese people in Hong Kong. METHODS: A cross-sectional study was conducted using a Hong Kong Hospital Authority Family Medicine Clinic as the sampling frame. People aged 35 to 70 years with recent orofacial pain symptoms participated. Standard questions were asked about orofacial pain symptoms and characteristics in the previous month, Oral Health Impact Profile (OHIP-14), General Health Questionnaire (GHQ-12), Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) depression/nonspecific physical symptoms (NPS) scales, sleep and illness behavior measures, and questions on pain disability, professional treatment-seeking, pain medication usage, and dental attendance were administered prior to a standard clinical assessment. Multiple logistic regression with a forward stepwise selection method was used for data analysis. RESULTS: Two hundred people with orofacial pain symptoms participated in the definitive study. Twenty-seven percent had sought professional advice. The majority had consulted a medical practitioner (66.7%) or dentist (40.7%), 16.7% had consulted a traditional Chinese medicine (TCM) practitioner, and the majority (60%) had taken pain medication. There was no significant association between different orofacial pain diagnoses and professional treatment-seeking (P = .602). Four independent factors were significantly related to an increased likelihood of treatment-seeking (P < .05): more frequent dental attendance for check-up (odds ratio [OR] > 3), time when pain was experienced during the past month (days) (OR > 5), multiple pain symptoms (OR = 4.99), and use of TCM when ill (OR = 3.31). CONCLUSION: Professional treatment-seeking for orofacial pain was low in this ethnic group. The strongest predictor of treatment-seeking for orofacial pain was an increase in the number of days when pain was experienced during the past month. Key factors associated with treatment-seeking should be considered when formulating community health outreach programs. A further validation study with a larger sample size is recommended to confirm the present findings.

Effects of smoking on healing response to non-surgical periodontal therapy: a multilevel modelling analysis.

AIM: To investigate the factors predicting non-surgical periodontal treatment responses using multilevel multiple regression. MATERIAL AND METHODS: Forty men (mean 45.6 years) were recruited; 20 were smokers. A 12-month reduction in probing pocket depth (PPD) and gain in probing attachment level (PAL) of 5814 sites were analysed, with 594 being initially diseased sites (initial PPD> or =5 mm). RESULTS: Variance Component models showed that site-level variations contributed about 70-90% of the total variance. About a 10% reduction of the total variations of PPD reduction in initially diseased sites was achieved with the inclusion of the 10 predictors in the multilevel multiple regression. Multilevel multiple regression showed that three predictors, subject level: non-smokers; tooth-level: anterior teeth; and site level: sites without plaque at baseline, were significantly associated with a greater reduction in PPD in initially diseased sites over the 12-month study period (p<0.05). No consistent predictor was found for PAL gain. CONCLUSION: Multilevel analysis was applied on periodontal treatment response data. Smokers showed less favourable PPD reduction at deep sites after non-surgical periodontal therapy.

Risk predictors of dental root caries: A systematic review.

OBJECTIVES: To identify the risk predictors of root caries and to describe their relationship with the incidence and increment of root caries. DATA: Observational longitudinal studies. SOURCES: Four electronic databases (PubMed, MEDLINE, EMBASE, and Scopus) (From 1 January 1990 to 31 January 2019). STUDY SELECTION: Information on the factors associated with the incidence or increment of decayed and filled root surfaces (DF-root) and/or decayed root surfaces (D-root) were extracted by two reviewers independently. The factors were put into six categories, namely social-demographic background, general health, health behaviors, fluoride exposure, oral health habits and oral health condition. From the 440 potential papers identified, 19 papers reporting on 16 cohort studies were finally included. The total sample size was 7340 participants from different countries worldwide, with age ranging from 20 to 100 years. Positive correlations between new root caries and age, baseline root caries experience, gingival recession and use of tobacco were reported while negative correlations were found for socio-economic status, good oral hygiene and use of fluorides. Mixed findings were detected for the association between new root caries and the number of natural teeth. CONCLUSION: This systematic review discovered a number of root caries risk predictors in different categories. People who are older, in lower socio-economic status or tobacco users, and those with more root caries experience, gingival recession and poor oral hygiene have higher risk of developing new root caries. CLINICAL SIGNIFICANCE: This systematic review provides support that improvement of oral hygiene, prevention of gingival recession, and use of fluoride would be useful strategy for prevention of new root caries.

Chronic orofacial pain in southern Chinese people: experience, associated disability, and help-seeking response.

AIMS: To investigate chronic orofacial pain experience, psychosocial impact, and help-seeking response in adult Chinese people in Hong Kong. METHODS: A cross-sectional population-based telephone interview survey identified 1352 randomly selected people aged > or =18 years. Standard questions were asked about current or episodic and prior (> or = 6 months) experience of 7 orofacial pain symptoms. Pain intensity and psychosocial impact were assessed through the Graded Chronic Pain Scale, and the help-seeking response was assessed using the 4-item Level of Expressed Need (LEN) measure. RESULTS: Current or episodic symptoms of orofacial pain were reported by 57.0% of respondents, and 13.2% of this group reported symptoms that had lasted for a 6 months (chronic subgroup). In the chronic subgroup, toothache was the most common symptom (42.2%) and oral sores the least common (7.8%). The mean pain intensity in the chronic pain subgroup was 46.6 (SD 21.7) with no age or gender differences (P > .05); 88.2% had low disability levels and 11.8% had high levels. 81.4% had low LEN scores and 18.6% had high scores, with no age/gender differences (P > .05). CONCLUSION: The prevalence of current/episodic orofacial pain was relatively high, whereas chronic orofacial pain was much less common. Although the intensity of chronic orofacial pain was significant, associated psychosocial disability was low, as was the level of perceived need for treatment. These findings may be related to more effective pain-coping strategies and greater acceptance of pain in this ethnic group compared to other ethnic groups.

Trends in self-reported oral health of US adults: National Health and Nutrition Examination Survey 1999-2014.

OBJECTIVE: Single-item self-reported oral health (SROH) is a convenient and reliable measure for the assessment of population-based oral health. However, little is known about trends and its associations among US adults. This study investigated trends in SROH (aged 20+ years) and the associated factors among adults living in the United States. METHODS: Self-reported oral health data for 41 621 adults aged 20+ years from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2014 were analysed. Survey-weighted descriptive statistics were computed to provide nationally representative estimates. Multivariable logistic regression was performed separately for each survey period with SROH as the primary outcome. Independent variables included were age, gender, race/ethnicity, education level and family poverty income ratio or PIR. Pooled survey-weighted multivariable logistic regression was also performed to consider possible time-changing effects. RESULTS: The survey-weighted proportions of "excellent or very good" in SROH increased from 27% in 1999-2000 (n = 4873) to 38% in 2013-2014 (n = 5765). Separate multivariable logistic analyses for each survey period suggested that females, Whites (vs Mexican and Black Americans) as well as respondents from high family PIR had higher odds of reporting their oral health as "excellent or very good" (P < .05). The pooled multivariable logistic model confirmed results in the separate logistic regression, and respondents in the more recent survey periods had higher probabilities of reporting "excellent or very good" oral health. Respondents aged 50-59 years were found to have relatively lower probabilities of reporting "excellent or very good" oral health, while people aged 20-29 years had higher probabilities than those aged 30-39 years. Compared to respondents with lower education, those with higher education were more likely to report their oral health as excellent or very good. CONCLUSIONS: Self-reported oral health improved from 1999 to 2014. In general, respondents who were young, female, White, had higher education or higher income or were surveyed in more recent years reported excellent or very good oral health.

The prognostic role of PD-L1 expression for survival in head and neck squamous cell carcinoma: A systematic review and meta-analysis.

BACKGROUND: Programmed death-ligand 1 (PD-L1) is an immune checkpoint that is primarily located on the surface of tumor cells. PD-L1 expression detected by immunohistochemistry (IHC) assays has been widely studied to predict survival outcomes in head and neck squamous cell carcinoma (HNSCC) recently. We aimed to review comprehensively the prognostic role of PD-L1 expression for survival in HNSCC. METHODS: We systematically searched PubMed, Embase, Web of Science, Cochrane Library and Scopus to identify studies investigating the prognostic role of PD-L1 expression in HNSCC. All studies published before March 31, 2018 were screened. Included studies were assessed using the Quality in Prognosis Studies (QUIPS) tool. Data were extracted and overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), disease-specific survival (DSS) were combined and presented as hazard ratios (HR) with 95% confidence interval (CI) using the generic inverse-variance method. RESULTS: Twenty-three studies with 3105 patients were analysed. The overall positive rate of PD-L1 in HNSCC was 0.42 (95% CI: 0.36-0.48). There was no significant difference between PD-L1-positive and -negative HNSCC patients in OS (HR: 0.98; 95% CI: 0.71-1.37; p = 0.93), DFS (HR: 1.07; 95% CI: 0.68-1.70; p = 0.76), and DSS (HR: 0.90; 95% CI: 0.63-1.29; p = 0.56). An improved PFS was observed in patients with positive PD-L1 expression (HR: 0.71; 95% CI: 0.55-0.93; p = 0.01). In patients with low CD8+ tumor-infiltrating T cells, a poorer OS was detected in patients with positive PD-L1 expression (HR: 1.90; 95% CI: 1.07-3.36; p = 0.03). Patients with HPV-positive HNSCC were associated with increased PD-L1 expression (OR: 1.99; 95% CI: 1.50-2.64; p < 0.001). However, PD-L1 expression showed no significant benefit on OS in HPV-positive HNSCC (HR: 1.04; 95% CI: 0.65-1.65; p = 0.88). CONCLUSIONS: PD-L1 expression detected by IHC was not recommended to predict survival in HNSCC patients. However, the positive PD-L1 expression might predict better PFS in patients with advanced HNSCC. The combined effects of PD-L1 expression and CD8+ tumor-infiltrating T cells should be further elucidated.

Distinct epidermal growth factor receptor and KRAS mutation patterns in non-small cell lung cancer patients with different tobacco exposure and clinicopathologic features.

PURPOSE: This study evaluated the mutational profile of epidermal growth factor receptor (EGFR) and KRAS in non-small cell lung cancers in Hong Kong and determined their relation with smoking history and other clinicopathologic features. EXPERIMENTAL DESIGN: Mutational profile of exons 18 to 21 of EGFR and codons 12, 13, and 61 of KRAS were determined in 215 adenocarcinomas, 15 squamous cell (SCC), and 11 EBV-associated lymphoepithelioma-like carcinomas (LELC). RESULTS: EGFR mutations were prevalent in adenocarcinomas (115 of 215), uncommon in LELC (1 of 11), and not found in SCC (P < 0.001). Among adenocarcinomas, mutations were associated with nonsmokers (83 of 111; P < 0.001), female gender (87 of 131; P < 0.001), and well-differentiated (55 of 86) compared with poorly differentiated (11 of 41) tumors (P < 0.001). Decreasing mutation rates with increasing direct tobacco exposure was observed, with 74.8% (83 of 111) in nonsmokers, 61.1% (11 of 18) in passive, 35.7% (10 of 28) in previous, and 19.0% (11 of 58) in current smokers. There were 53% amino acid substitutions, 43% in-frame deletions, and 4% insertions. Complex patterns with 13% double mutations, including five novel substitutions, were observed. For KRAS, mutations occurred in adenocarcinoma only (21 of 215) and were associated with smokers (11 of 58; P = 0.003), men (14 of 84; P = 0.009) and poorly differentiated (7 of 41) compared with well-differentiated (4 of 86) tumors (P = 0.037). EGFR and KRAS mutations occurred in mutually exclusive tumors. Regression analysis showed smoking history was the significant determinant for both mutations, whereas gender was a confounding factor. CONCLUSION: This study shows EGFR mutations are prevalent in lung adenocarcinoma and suggests that it plays an increasing oncogenic role with decreasing direct tobacco damage.