PAR Index Research Articles

4-Pyridoxic Acid/Pyridoxine Ratio in Patients with Type 2 Diabetes is Related to Global Cardiovascular Risk Scores.

Background: Vascular diseases are multifactorial and several risk factors may have synergetic effect on the global vascular risk. Among patients with diabetes, we investigated whether vitamin B6 species differ according to global cardiovascular risk. Methods: The present observational study included 122 patients with type 2 diabetes (mean (SD) age = 69.9 (9.1) years; 50% men). Concentrations of vitamin B6 vitamers were measured. Classical blood biomarkers and risk factors were used to compute a multivariate risk score. Results: Plasma concentrations of 4-pyridoxic acid were higher in patients with high risk versus those with low risk scores (48.2 (63.7) vs. 31.9 (15.0) nmol/L; p = 0.031). Plasma pyridoxine was significantly lowered in patients at high risk (2.8 (28.4) vs. 38.1 (127.8) nmol/L; p = 0.003). PAr index (4-pyridoxic acid/pyridoxal + pyridoxal 5′-phosphate) (1.05 (0.07) vs. 0.84 (0.06); p = 0.017) and the ratio of 4-pyridoxic acid/pyridoxine (7.0 (4.8) vs. 3.9 (3.2); p < 0.001) were higher in patients at high risk. After adjustment for cystatin C and C-reactive protein, only pyridoxine and 4-pyridoxic acid/pyridoxine ratio remained significantly different according to vascular risk scores. 4-Pyridoxic acid/pyridoxine ratio was the best marker to discriminate between patients according to their risk scores—area under the curve (AUC) (95% confidence intervals (CI)) = 0.72 (0.62–0.81). 4-Pyridoxic acid/pyridoxine ratio was directly related to plasma levels of soluble vascular cell adhesion molecule 1. Conclusion: Vitamin B6 metabolism was shifted in patients with multiple vascular risk factors. The catabolism to 4-pyridoxic acid was enhanced, whereas the catabolism to pyridoxine was lowered. High 4-Pyridoxic acid/pyridoxine ratio is independently associated with global cardiovascular risk.

Vitamin B6 catabolism and lung cancer risk: results from the Lung Cancer Cohort Consortium (LC3)

Increased vitamin B6 catabolism related to inflammation, as measured by the PAr index (the ratio of 4-pyridoxic acid over the sum of pyridoxal and pyridoxal-5'-phosphate), has been positively associated with lung cancer risk in two prospective European studies. However, the extent to which this association translates to more diverse populations is not known. For this study, we included 5323 incident lung cancer cases and 5323 controls individually matched by age, sex, and smoking status within each of 20 prospective cohorts from the Lung Cancer Cohort Consortium. Cohort-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between PAr and lung cancer risk were calculated using conditional logistic regression and pooled using random-effects models. PAr was positively associated with lung cancer risk in a dose-response fashion. Comparing the fourth versus first quartiles of PAr resulted in an OR of 1.38 (95% CI: 1.19-1.59) for overall lung cancer risk. The association between PAr and lung cancer risk was most prominent in former smokers (OR: 1.69, 95% CI: 1.36-2.10), men (OR: 1.60, 95% CI: 1.28-2.00), and for cancers diagnosed within 3 years of blood draw (OR: 1.73, 95% CI: 1.34-2.23). Based on pre-diagnostic data from 20 cohorts across 4 continents, this study confirms that increased vitamin B6 catabolism related to inflammation and immune activation is associated with a higher risk of developing lung cancer. Moreover, PAr may be a pre-diagnostic marker of lung cancer rather than a causal factor.

Changes in orthodontic occlusal indices after semi-rapid maxillary expansion

ObjectivesTo quantify malocclusion complexity changes after semi-rapid maxillary expansion. Materials and methodThe study sample consisted of pre- and postexpansion dental models and frontal intraoral photographs of 195 consecutive patients treated for maxillary expansion using a removable plate and a semi-rapid screw activation protocol. Differences between the pre- and posttreatment scores of the weighted Peer Assessment Rating Index (PAR), dental health component (DHC), aesthetic component (AC) of Index of Orthodontic Treatment Need (IOTN), and Discrepancy Index (DI) were analyzed. ResultsThe intraclass correlation coefficient test to assess the intraobserver error in PAR index and DI was performed and the value was found to be more than 0.80. The kappa score of 0.923 and 0.926 was observed in DHC and AC indices of IOTN, respectively, suggesting a good intraobserver agreement of scores. The pre- and postexpansion mean values in all the indices showed a significant reduction (P < 0.001). The IOTN-DHC, PAR, IOTN-AC, and DI scores showed improvements in 87.2%, 81.6%, 80.5%, and 72.8% of the subjects, respectively. The percentage change in the scores was maximum for IOTN-DHC (−27.8%) followed by PAR (−23.3%). IOTN-AC and DI showed approximately 20% improvement each. More than 25% improvement in scores was seen in 47% to 82% of the subjects. ConclusionThe study suggests that there is a significant decrease in orthodontic treatment need and treatment complexity after semi-rapid maxillary expansion treatment.

Efficiency of class III malocclusion treatment with 2-premolar extraction and molar distalization protocols

Different treatment protocols have been implemented for management of Class III malocclusion with aim of achieving ideal occlusal goals. The aim of current study was to compare the efficiency of Class III treatment with mandibular 2-premolar extraction and mandibular molar distalization protocol. This retrospective cross sectional study was conducted on pre-treatment and post-treatment dental casts of 60 orthodontic patients who had Class III malocclusion and were treated with a mandibular dentition distalization and mandibular 2-premolars extraction protocol. The study was conducted at orthodontic departments of Dental Section, Faisalabad Medical University/Punjab Medical College and de'Montmorency College of Dentistry, Pakistan. The sample was classified into 2 groups. Group A consisted of 30 patients (20 females, 10 males) (mean age, 18.02years) treated with distalization protocol and Group B consisted of 30 patients (18 females, 12 males) (mean age, 18.97years) treated with mandibular 2-premolars extraction protocol. To compare the efficiency of the treatment protocol in each group, the initial and final occlusal results were assessed on dental models using PAR index while treatment efficiency was assessed using a treatment efficiency index (TX). The groups were compared with t and Mann-Whitney tests. There were no significant differences in the initial age, treatment time, treatment efficiency and any occlusal feature between the groups. Treatment efficiency of Class III malocclusions with mandibular 2-premolar extractions or mandibular dentition distalization protocol is similar.

Results from the European Prospective Investigation into Cancer and Nutrition Link Vitamin B6 Catabolism and Lung Cancer Risk.

Circulating pyridoxal-5'-phosphate (PLP) has been linked to lung cancer risk. The PAr index, defined as the ratio 4-pyridoxic acid/(pyridoxal + PLP), reflects increased vitamin B6 catabolism during inflammation. PAr has been defined as a marker of lung cancer risk in a prospective cohort study, but analysis of a larger numbers of cases are needed to deepen the significance of this study. Here, we conducted a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC, n = 521,330), which included 892 incident lung cancer cases and 1,748 controls matched by center, gender, date of blood collection, and date of birth. The association of PAr with risk of lung cancer was evaluated by using conditional logistic regression. Study participants with elevated PAr experienced higher risk of lung cancer in a dose-response fashion, with a doubling in PAr levels associated with 52% higher odds of lung cancer after adjustment for tobacco smoking, serum cotinine levels, educational attainment, and BMI [OR, 1.52; 95% confidence interval (CI) 1.27-1.81; P < 0.001]. Additional adjustment for intake of vegetables and fruits and physical activity did not materially affect risk association. The association of PAr with lung cancer risk was similar in both genders but slightly stronger in former smokers and in participants diagnosed with squamous cell carcinoma. This study provides robust evidence that increased vitamin B6 catabolism is independently associated with a higher risk of future lung cancer.Significance: This large cohort study firmly establishes an association between an index of vitamin B6 levels with lung cancer risk. Cancer Res; 78(1); 302-8. ©2017 AACR.

The efficacy of orthodontic treatments for anterior crowding with Invisalign compared with fixed appliances using the Peer Assessment Rating Index.

The purpose of this retrospective study was to determine the efficacy of Invisalign in a large sample of patients compared to fixed appliances. The test group consisted of 100 patients treated with Invisalign compared with a control group treated with conventional fixed appliances matched for sex, age, and initial severity of malocclusion based on the amount of anterior dental crowding (Little Index) and the Peer Assessment Rating (PAR Index) scores. The retainer used was a 0.0175-inch multistranded stainless-steel wire bonded from canine-to-canine in the mandibular arch and from lateral inisor-to-lateral incisor in the maxillary arch. A paired t test was used to compare both initial and final PAR scores. There was an overall 80.9% improvement, and 63 subjects did not need any refinement. The mean number of aligners used was 14 (+ 15 for the refinements) in the maxillary arch and 29 (+ 14 for the refinements) in the mandibular arch. The mean duration of treatment was 14 months (+ 7 months for the refinements). Significant statistical differences were found in the posttreatment scores, within both the Invisalign group and the control group. No differences were found in the follow-up scores. Additionally, the duration of treatment was 4 months longer in the control group. More than 90% of the subjects treated with Invisalign achieved a significant improvement, as shown by the PAR scores. A need for additional aligners was reported for 37% of the patients. Fixed bonded retainers seem to be a good option in preventing tooth relapse after Invisalign and fixed conventional treatments.

The PAr index, an indicator reflecting altered vitamin B-6 homeostasis, is associated with long-term risk of stroke in the general population: the Hordaland Health Study (HUSK)

ABSTRACTBackgroundVitamin B-6 homeostasis is altered during inflammation and immune activation. It is unknown whether altered vitamin B-6 homeostasis is associated with the risk of stroke.ObjectiveWe investigated the relation between the ratio plasma 4-pyridoxic acid: (pyridoxal + pyridoxal-5′-phosphate) (PAr) as an indicator of altered vitamin B-6 homeostasis and the risk of stroke in the general population.DesignWe conducted a prospective analysis of the community-based Hordaland Health Study (HUSK) in 6891 adults (born during 1925–1927 and 1950–1951) without known stroke at baseline (1998–1999). Participants were followed via linkage to the CVDNOR (Cardiovascular Disease in Norway) project and the Cause of Death Registry. HRs and 95% CIs were calculated using Cox proportional hazards analyses.ResultsA total of 390 participants (193 men and 197 women) developed stroke over a median follow-up period of 11 y. Study participants with elevated PAr experienced a higher risk of incident stroke in an essentially linear dose-response fashion. The HR (95% CI) for the highest compared with the lowest quartile of PAr was 1.97 (1.42, 2.73; P-trend <0.001) for total stroke and 2.09 (1.42, 3.09; P-trend <0.001) for ischemic stroke after adjustment for age, sex, body mass index (BMI), smoking, education, physical activity, estimated glomerular filtration rate, hypertension, diabetes, total cholesterol, and statin use. PAr had greater predictive strength than did C-reactive protein, current smoking, diabetes, hypertension, estimated glomerular filtration rate, and physical activity. The associations were similar in subgroups stratified by age group, sex, BMI, current smoking, hypertension, diabetes, and statin use at baseline.ConclusionsHigher plasma PAr was independently associated with increased risk of incident stroke in all participants and across all subgroups stratified by conventional risk predictors. Our novel findings point to and expand the range of inflammation and immune activation processes that may be relevant for the pathogenesis and prevention of stroke. This trial was registered at clinicaltrials.gov as NCT03013725.

Kynurenine Pathway Metabolites in Alzheimer's Disease.

Metabolites of tryptophan, produced via the kynurenine pathway (kynurenines), have been linked to Alzheimer's disease (AD) in small cohorts with conflicting results. To compare differences in plasma kynurenine levels between AD and controls and identify potential associations with cognition. The study included 65 histopathologically-confirmed AD patients and 65 cognitively-screened controls from the Oxford Project to Investigate Memory and Ageing (OPTIMA) cohort. Cognition was assessed using the Cambridge Cognitive Examination (CamCog). Tryptophan, kynurenines, neopterin, and vitamin B6 forms were measured in plasma by liquid chromatography-tandem mass spectrometry. Non-parametric statistics, logistic regression and standardized robust regressions were applied with a false discovery rate of 0.05. Tryptophan, xanthurenic acid, 3-hydroxyanthranilic acid, and quinolinic acid were lower in AD (Odds ratios (ORs) 0.24 -0.47; p-values <0.001 -0.01). Pyridoxal 5'phosphate did not differ between AD and controls. Kynurenine, anthranilic acid, quinolinic acid, and markers of immune activation (neopterin, kynurenine/tryptophan ratio, and the PAr index (Pyridoxic acid/(Pyridoxal 5'phosphate + Pyridoxal)) increased with age (β 0.31 -0.51; p-values <0.001 -0.006). Xanthurenic acid decreased with age (β: -0.42, p < 0.001). Elderly AD patients with high quinolinic acid performed worse on the CamCog test, indicated by a significant age*quinolinic acid interaction (β 0.21, p < 0.001). Plasma concentrations of several kynurenines were lower in patients with AD compared to controls. Low xanthurenic acid occurred in both AD and with aging. Inflammation-related markers were associated with age, but not AD. However, elevated QA was associated with poor cognition in older AD patients.

Long-term (≥15 years) post-treatment changes and outcome quality after Class II:1 treatment in comparison to untreated Class I controls.

To investigate the long-term (≥15 years) post-treatment (Tx) occlusal changes and outcome quality after Class II:1 Tx. Herbst-MBA Tx had been performed at age 12.8 ± 2.7 years in 119 patients. A recall was conducted and study models from before and after active Tx, after retention as well as after recall were evaluated using standard occlusal variables and the PAR index. These data were compared to 31 untreated Class I controls. 52 out of 119 patients could be located and participated at 33.6 ± 3.1 years. Compared to the 67 patients who did not participate in the recall, the pre- and post-Tx occlusal data of the participants did not differ systematically; however, the PAR scores were higher by 3.0-4.7 points at all times. Pre-Tx, the mean values of the 52 participants were: PAR = 27.2 ± 7.6, Class II molar relationship (MR) = 0.7 cusp widths (cw), overjet = 8.2 mm, overbite = 4.1 mm. After Tx, the PAR score was 3.4 ± 2.2. A Class I MR (0.0 ± 0.1 cw) with normal overjet (2.3 ± 0.7 mm) and overbite (1.3 ± 0.7 mm) existed. At recall, a mild PAR score increase to 8.2 ± 5.5 points had occurred; this was mainly due to increased overjet and overbite values (3.6 ± 1.1 and 2.8 ± 1.6 mm) while the MR was stable (0.0 ± 0.2 cw). For all these variables, similar findings were made in the untreated controls. The occlusal outcome of Class II:1 Tx showed very good long-term stability. While mild changes occur post-Tx, the long-term result is similar to untreated Class I controls.

Treatment duration and gingival inflammation in Angle’s Class I malocclusion patients treated with the conventional straight-wire method and the Damon technique: a single-centre, randomised clinical trial

To compare the duration of orthodontic treatment and Gingival Index (GI) scores in Class I malocclusion patients treated with a conventional straight-wire method (CG) or the Damon technique (DT). Two-arm, parallel, randomised clinical trial Setting: A postgraduate orthodontic clinic Participants: Patients with a balanced facial profile, a full permanent dentition and Angle's Class I malocclusion with moderate crowding. The primary outcome was the duration of orthodontic treatment in months. GI scores throughout treatment were secondary outcomes and the PAR index was also assessed. Randomisation was accomplished using a table of random numbers and the allocation was concealed in sequentially numbered and opened, opaque, sealed envelopes. Blinding was applicable for PAR assessment only. Comparison of data between groups was performed with appropriate tests for independent samples. Twenty-two patients were randomly allocated to treatment in a 1:1 ratio to either CG or DT group. Age at the start of treatment, initial PAR index and GI scores were similar between groups. All patients completed the study, but the total duration of orthodontic treatment was almost half of the initial assumption. No statistically significant differences were observed in treatment duration (CG: Mean ([Formula: see text]) = 14.5 months, Standard Deviation (SD) = ±3.03; DT: [Formula: see text] months, SD = ±2.93; 95% Confidence Interval: -0.40 to 4.90; P = 0.093; t-test). The two groups did not differ statistically regarding the GI scores during the observational period. No serious harms were observed other than gingival inflammation associated with oral biofilm accumulation. The present study did not reveal statistically significant differences between the compared, conventional straight-wire method and Damon technique-treated, Angle's Class I malocclusion groups regarding total treatment duration and GI scores.

Excellent versus unacceptable orthodontic results: influencing factors.

To retrospectively compare patients with excellent and unacceptable orthodontic treatment results with respect to possible prognostic factors. All patients, who completed treatment at the Department of Orthodontics of the Justus-Liebig-University Giessen, Germany between 1993 and 2009 with an excellent or unacceptable outcome according to the Ahlgren index. Possibly influencing factors regarding case history, treatment, cephalometrics, and plaster casts were analyzed. Furthermore, PAR index pre- and post-treatment was compared. The explorative statistical analysis was performed using Fishers Exact test, Chi-square test, and Mann-Whitney U-test. Out of 1653 patients, treatment outcome was excellent in 226 (13.7 per cent) and inacceptable in 56 (3.4 per cent) patients. For the remaining cases, a good or acceptable outcome was assessed. Pretreatment PAR scores showed no difference between the excellent and unacceptable group. The following factors were significantly more common in the unacceptable group: male predominance (P = 0.009), occurrence of general diseases (P = 0.003), habits (P < 0.001), prolonged active appliance treatment duration (P = 0.014), negative cooperation (P < 0.001), denial of recommended appliance or premature removal of appliances (P < 0.001), decreased pretreatment overbite (P = 0.005), and hyperdivergent jaw base relationships (P = 0.005). Patient cooperation remains the outstanding parameter determining treatment success. A proportionally higher frequency of unacceptable treatment results must be expected in patients with open bite configurations (skeletally, dentally, and functionally).

Research insights: Orthodontic therapists – has their introduction affected outcomes?

Objective To assess the effect of the introduction of orthodontic therapists (OTs) on the quality of orthodontic treatment outcomes in two specialist orthodontic practices in the UK. Study design Retrospective cross sectional observational study. Setting Multi-centre evaluation at two specialist orthodontic practices in Yorkshire. Data collection was carried out during 2014. Materials and methods The treatment undertaken by three specialist orthodontic clinicians (A, B and C) was evaluated at two time points. The first time point (T1) was before the introduction of OTs when the specialist orthodontic clinicians were solo operators. The second time point (T2) followed the introduction of OTs. Patients at T2 had their treatment planned by a specialist orthodontist and were seen for care by both the orthodontist and an OT who had been qualified for a minimum of three years. A sample size of 30 orthodontic patients per clinician at each time point was chosen. Included participants had completed a course of fixed appliance therapy. They were consecutively selected from cases that had been completed in the specified time frame for each clinician. Main outcome measures The quality of treatment was assessed objectively using the quantitative Peer Assessment Rating index (PAR index). Data extracted from the specialist practice databases also allowed conclusions to be drawn about the length of treatment time and number of appointments in each treatment group. Results and conclusions There appears to have been no change in orthodontic treatment outcomes following the introduction of supervised OTs at two specialist orthodontic practices.

Orthodontic therapists - has their introduction affected outcomes?

Objective To assess the effect of the introduction of orthodontic therapists (OTs) on the quality of orthodontic treatment outcomes in two specialist orthodontic practices in the UK.Study design Retrospective cross sectional observational study.Setting Multi-centre evaluation at two specialist orthodontic practices in Yorkshire. Data collection was carried out during 2014.Materials and methods The treatment undertaken by three specialist orthodontic clinicians (A, B and C) was evaluated at two time points. The first time point (T1) was before the introduction of OTs when the specialist orthodontic clinicians were solo operators. The second time point (T2) followed the introduction of OTs. Patients at T2 had their treatment planned by a specialist orthodontist and were seen for care by both the orthodontist and an OT who had been qualified for a minimum of three years. A sample size of 30 orthodontic patients per clinician at each time point was chosen. Included participants had completed a course of fixed appliance therapy. They were consecutively selected from cases that had been completed in the specified time frame for each clinician.Main outcome measures The quality of treatment was assessed objectively using the quantitative Peer Assessment Rating index (PAR index). Data extracted from the specialist practice databases also allowed conclusions to be drawn about the length of treatment time and number of appointments in each treatment group.Results and conclusions There appears to have been no change in orthodontic treatment outcomes following the introduction of supervised OTs at two specialist orthodontic practices.

Factors influencing orthodontic treatment time for non-surgical Class III malocclusion.

ABSTRACTTo improve orthodontic treatment efficiency, orthodontists must know which variables could interfere with orthodontic treatment time.Objective:To identify variables and their effect size on orthodontic treatment time of Class III malocclusion.Material and Methods:Forty-five Class III malocclusion cases were selected from 2008 patients’ records. Clinical charts, cephalometric radiographs, and pre and posttreatment dental casts were evaluated. Age, sex, PAR index at T1 and T2, overjet, missing teeth, extractions, number of treatment phases, missed appointments, appliance breakages, and cephalometric variables SNA, SNB, ANB, Wits, SnGoGn, CoA, CoGn, IMPA, 1.PP were investigated by multiple linear regression analysis and stepwise method at p<0.05. The sample was also divided into two groups: Group 0-2 (patients who had missed two clinical appointments or less) and Group >2 (patients who missed more than 2 appointments), to detect the influence of this data on treatment time and the quality of the treatment (PAR T2).Results:Average treatment time was 30.27 months. Multiple regression analysis showed that missed appointment (R2=0.4345) and appliance breakages (R2=0.0596) are the only variables able to significantly predict treatment duration. Treatment time for patients who missed more than 2 appointments was nearly one year longer. However, no significant influence on PAR T2 was observed for those patients.Conclusion:Orthodontic treatment duration in Class III patients is mainly influenced by factors related to patient compliance. Patients who missed more appointments did not show worse orthodontic finishing, but longer treatment. No occlusal, cephalometric, or demographic variable obtained before treatment was able to give some significant prediction about treatment time in Class III patients.

Direct and Functional Biomarkers of Vitamin B6 Status.

Measures of B6 status are categorized as direct biomarkers and as functional biomarkers. Direct biomarkers measure B6 vitamers in plasma/serum, urine and erythrocytes, and among these plasma pyridoxal 5'-phosphate (PLP) is most commonly used. Functional biomarkers include erythrocyte transaminase activities and, more recently, plasma levels of metabolites involved in PLP-dependent reactions, such as the kynurenine pathway, one-carbon metabolism, transsulfuration (cystathionine), and glycine decarboxylation (serine and glycine). Vitamin B6 status is best assessed by using a combination of biomarkers because of the influence of potential confounders, such as inflammation, alkaline phosphatase activity, low serum albumin, renal function, and inorganic phosphate. Ratios between substrate-products pairs have recently been investigated as a strategy to attenuate such influence. These efforts have provided promising new markers such as the PAr index, the 3-hydroxykynurenine:xanthurenic acid ratio, and the oxoglutarate:glutamate ratio. Targeted metabolic profiling or untargeted metabolomics based on mass spectrometry allow the simultaneous quantification of a large number of metabolites, which are currently evaluated as functional biomarkers, using data reduction statistics.

The Impact of Fixed Orthodontic Therapy in Correction of Malocclusion in Adults

Objective: To measure the impact of fixed orthodontic therapy in the correction of malocclusion in adults and to evaluate the influence of factors associated with this impact. Methods: The sample consisted of 288 adult patients who had undergone fixed orthodontic therapy. The adequacy of orthodontic treatment was assessed by the PAR index in models of initial and final study. Associated factors were divided into two groups: socio-economic demographic variables (gender, education level, type of service, age at end of treatment), and the independent orthodontic variables (DHC-IOTN, AC-IOTN, satisfactory use of retainer, conducting speech therapy, and main complaints). For data analysis, we used the chisquare tests and multivariate logistic regression for a confidence level of 95%. Results: Independent of associated factors, the improvement of the treated cases was greater than 88.2% of the sample, with significant improvement in cases with moderate or severe initial need of treatment (p = 0.008) and in patients older than 25 years at the time of treatment (p = 0.015). Conclusion: The orthodontic therapy resulted in significant improvement, especially in cases with moderate or severe orthodontic treatment need and in adults over the age of 25 years.

Herbst appliance: combination with fully individualized lingual vs conventional buccal braces vs surgery

The Herbst appliance –first presented to the dental community in 1909- is a traditional fixed bite-jumping device aiming at skeletal and/or dentoalveolar correction of class II malocclusions. It is especially indicated in the permanent dentition at or just after the pubertal peak of growth (Pancherz, 1997). An upper age limit for successful treatment with the Herbst device is difficult to define (Pancherz and Ruf, 2008). The oldest patient treated with this appliance was –to the best knowledge of literature by the author– 44.4 years old (Ruf and Pancherz, 2006). The Herbst device can be considered an alternative to orthognathic surgery in borderline adult skeletal class II malocclusions, especially when a great facial improvement is not the main treatment goal (Ruf and Pancherz, 2004). Orthodontic therapy with fully individualized lingual appliances does not only offer evident aesthetic superiority and a high accuracy (Grauer and Proffit, 2011), but also -and this is decisive in comparison to treatment with conventional braces and wires- medical advantages with respect to avoidance of white spot lesions, that progress or develop approximately 5 times less (van der Veen et al., 2010) and in combination with the Herbst appliance: • with a mean of only 2.2°+/-1° (Wiechmann et al., 2010) as compared to data from literature (El-Fateh und Ruf, 2011) undesired proclination of the lower front teeth is considerably less; due to the exact fit of slot and wire even an uprighting of the mandibular incisors is possible (Wiechmann et al., 2008), if planned in the set up (Wiechmann et al., 2010). • as compared to data given in literature the mean correction of the axis of the upper incisors and the mean reduction of PAR index are better, the mean reduction of overjet is better or identical (Vu et al., 2012). • in the event of agenesis of teeth distal to the lower canines and planned orthodontic space closure additional (skeletal) anchorage is unnecessary, as mesialization can be performed against the force vector of the telescopes.

’Where did the time go?’ – an analysis of orthodontic care in a district general hospital over a 24-year period

A longitudinal prospective analysis was carried out within a District General Hospital's Orthodontic Department over the entire career of a Consultant Orthodontist, using the IOTN and PAR indices, to monitor continuously the ‘appropriateness’ and ‘quality’ of orthodontic treatment undertaken. Following the retirement of that Consultant, the cumulative results are presented. The results confirm that referrals to the Department were appropriate, demonstrate a generally high standard of treatment for a large number of patients over that period, and a trend towards the treatment of more complex cases, enabling some conclusions to be drawn. Clinical Relevance: This paper demonstrates the recent level of activity and quality of an Orthodontic Service within a District General Hospital.

Carbon dioxide fluxes over a temperate meadow in eastern Inner Mongolia, China

Understanding the carbon dynamics in grassland is essential to precisely estimate global atmospheric carbon budget in response to climatic change. Eddy flux measurements were carried out during 2011 and 2012 to characterize seasonal and annual variability of carbon exchanges above a temperate meadow in eastern Inner Mongolia, China. The CO2 flux showed obvious diurnal variations and the monthly mean amplitudes of diurnal course followed June/July > August > May > September. The daily maximum NEE reached up to −8.0 and −7.7 g C m−2 for 2011 and 2012, respectively. CO2 uptake was mainly from May to August, with seasonal peaks of −16.0 g C m−2 day−1 in both two years. Gross primary production (GPP) and ecosystem respiration (Re) were −1,084.5, 987.1 g C m−2 year−1 in 2011, and −1,123.3, 1,040.2 g C m−2 year−1 in 2012, respectively. The meadow acted as a stable carbon sink, with integrated net ecosystem exchange (NEE) of −97.4 and −83.1 g C m−2 year−1 for 2011 and 2012, respectively. Compared with 2011, the ecosystem assimilated more carbon and meanwhile respired even more, leading to a less carbon sequestration in 2012. PAR and leaf area index (LAI) dominated the seasonal variations in NEE, with PAR explaining 61–69 % of the variance in NEE as LAI maintaining the plateau during June to July. Harvest significantly decreased ecosystem carbon uptake. The interannual variability in GPP and Re resulted primarily from the variations in temperature and its effect on biomass growth.

The PAR index for evaluation of treatment outcomes in orthodontics: A clinical audit of 50 cases

In the context of this study, a clinical audit of cases treated by a single orthodontist was carried out to illustrate one practical application of the PAR index. Fifty pairs of dental casts taken from the patient group before and at the end of orthodontic treatment were evaluated by an orthodontist trained in the use of the PAR index. This evaluation shows that the average overall PAR score for the subjects included in the study fell from an initial value of 25.64 ± 11.73 points to 1.78 ± 2.79 points at the end of orthodontic treatment. The average reduction attributable to orthodontic treatment was 23.86 ± 0.95 points, for an average percentage reduction of 93.36 ± 9.02%. When cases were classified according to the degree of improvement suggested by the nomogram of the PAR index, 23 (46%) were in the "Improved" category after treatment, and 27 cases (54%) in the "Greatly improved" category. This adds up to a total of 100% in these two categories, with none in the "No better" or "Worse" categories. It should be recalled that a high standard of orthodontic treatment is considered to be reached when the average percentage reduction of the PAR score exceeds 70% and when the number of cases in the "Worse or no better" category is below 5%.