Routine Scaling Research Articles

Benefits of Dental Scaling and Polishing in Adults: A Rapid Review and Evidence Synthesis.

This rapid review assessed evidence to inform policy on the clinical effectiveness and optimal frequency of dental scaling and polishing (S&P) for adults, including those with low incomes eligible for the Canadian Dental Care Plan. A rapid review was conducted according to Cochrane Recommendations for Rapid Reviews. Populations included all adults, adults with periodontitis, and those with inequitable access to dental care. Primary outcomes included gingival inflammation, probing depths, and tooth loss. Secondary outcomes included oral health-related quality of life and economic impact. Four databases were searched for randomized clinical trials, systematic reviews, cohort studies, and practice guidelines. Risk of bias was evaluated using Cochrane Risk of Bias, Newcastle-Ottawa, ROBIS, and AGREE II tools. A qualitative synthesis was planned. In total, 3,181 references were retrieved: 4 applied to "all adults" and 4 to those with periodontitis. All reports had low risk of bias. One systematic review and one multicenter trial of adults with regular dental care found no clinical benefit regardless of S&P interval; however, patients valued and were willing to pay for regular scaling. One claims-based study reported regular S&P reduced tooth loss, and 2 clinical practice guidelines found a reduced risk of future attachment and tooth loss, lower overall health care costs for diabetes, and reduced costs for and incidence of acute myocardial infarction in those with regular S&P. There were no studies of underserved populations. For adults with no or early periodontal disease and regular access to dental care, routine S&P may have little clinical benefit but reduces tooth loss and some health care expenses. In patients with periodontitis, scaling intervals tailored to individual risk profile and periodontal status can maintain health. There is no evidence on the impact of routine S&P on patients with barriers accessing care. In terms of the benefits of routine scaling and polishing in adults, this rapid review found mixed evidence with a high level of certainty due to minimal risk of bias in the appraised studies for "regular dental attenders" and those with a diagnosis of periodontal diseases. Tailored intervals for dental scaling are beneficial for those diagnosed with periodontitis but may not provide the clinical benefits previously expected for adults at low risk. There is no evidence that dental polishing is effective. No evidence was found to support recommendations about the clinical effectiveness of scaling or the most appropriate recall intervals for scaling for low-income Canadians eligible for dental services under the new Canadian Dental Care Plan.

Association between periodontitis treatment and dementia in Taiwanese adults

BackgroundThe chronic systemic inflammatory response in periodontitis may be a potential risk factor for dementia, especially in adults. This study determined the association between periodontal treatment and dementia in adults and evaluated the effect of regular scaling treatment on the risk of dementia in this population.MethodsThis case–control study identified 18,930 patients with a dementia-related diagnosis from the Taiwan National Health Insurance Research Database. Scaling and periodontal emergency treatments were evaluated after 1 year and 3 years. Using multivariable logistic regression analysis to evaluate the association between periodontal emergency treatment and dementia risk.ResultsThe results showed that scaling treatment rates were lower in the dementia cohort than the non-dementia cohort after 1 and 3 years. Patients who received periodontal emergency treatment within 3 years had a significantly increased risk of dementia. Furthermore, patients with periodontitis who did not receive scaling treatment within 3 years had a higher risk of dementia than patients without periodontitis (OR, 1.22; 95% CI, 1.10–1.35).ConclusionThis study demonstrated that periodontitis and dementia are associated, and that periodontitis is a risk factor for dementia in adults. The risk of dementia was dependent on the periodontal health status of adults, and our findings suggest that regular scaling can reduce the incidence of dementia in adults. Therefore, regular and routine scaling treatment is suggested for adults.

Routine Dental Polishing for Oral Health

What Is the Issue?
 
 Professional dental care is important to help maintain oral health. Routine dental cleaning usually includes both scaling and polishing. Scaling is the removal of plaque and tartar from the crown and root surfaces of teeth. Polishing is the removal of residual plaque and external stains from the teeth.
 To support decisions about the optimal components for professional dental cleaning, it is important to understand the potential benefits and harms of routine dental polishing when compared to no routine dental polishing.
 
 What Did We Do?
 
 We searched for clinical and cost-effectiveness literature comparing routine dental polishing with no routine dental polishing. We also looked for evidence-based guidelines that provide recommendations about the use of routine dental polishing for the maintenance of oral health in adults and children.
 An information specialist conducted a search of peer-reviewed and grey literature sources published between January 1, 2018, and September 28, 2023.
 Documents were excluded if we could not isolate the effects of dental polishing from other dental procedures or if polishing techniques were used for a purpose other than the routine polishing of teeth.
 
 What Did We Find?
 
 We did not find any studies directly evaluating the clinical or cost-effectiveness of routine dental polishing versus no routine dental polishing, or guidelines about the use of routine dental polishing, that met the inclusion criteria for this review.
 We identified limited literature that examines the combined effects of routine scaling and polishing. Research is needed that distinguishes the effects of routine dental polishing from the effects of other dental procedures.
 
 What Does This Mean?
 
 Without comparative clinical or cost-effectiveness evidence about routine dental polishing versus no routine dental polishing, decision-makers may also wish to consider that patients value routine scaling and polishing, and that the cost of dental care may be a barrier to visiting the dentist for some people.
 New polishing methods, such as air powder polishing, may also be useful to consider when making decisions about routine polishing to support dental health. These methods include some of the benefits of scaling and may present opportunities to reduce periodontal inflammation or the length of a dental appointment.

The Development of Thermoresponsive Polymeric Simvastatin Prodrug for the Treatment of Experimental Periodontitis in Rats.

Periodontitis (PD) is a severe inflammatory gum pathology that damages the periodontal soft tissue and bone. It is highly prevalent in the US, affecting more than 47% of adults. Besides routine scaling and root planing, there are few effective treatments for PD. Developed as an effective treatment for hyperlipidemia, simvastatin (SIM) is also known for its well-established anti-inflammatory and osteogenic properties, suggesting its potential utility in treating PD. Its clinical translation, however, has been impeded by its poor water-solubility, lack of osteotropicity, and side effects (e.g., hepatoxicity) associated with systemic exposure. To address these challenges, an N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-based thermoresponsive polymeric prodrug of SIM (ProGel-SIM) was developed as a local therapy for PD. Its aqueous solution is free-flowing at 4 °C and transitions into a hydrogel at ∼30 °C, allowing for easy local application and retention. After a thorough characterization of its physicochemical properties, ProGel-SIM was administered weekly into the periodontal pocket of an experimental rat model of PD. At 3 weeks post initiation of the treatment, the animals were euthanized with palate isolated for μ-CT and histological analyses. When compared to dose equivalent simvastatin acid (SMA, active form of SIM) treatment, the rats in the ProGel-SIM treated group showed significantly higher periodontal bone volume (0.34 mm3 vs 0.20 mm3, P = 0.0161) and less neutrophil (PMN) infiltration (P < 0.0001) and IL-1β secretion (P = 0.0036). No measurable side effect was observed. Collectively, these results suggest that ProGel-SIM may be developed as a promising drug candidate for the effective clinical treatment of PD.

Perception of Patients Regarding Dental Scaling and Aesthetics, Attending Dental Care in a Tertiary Care Hospital

Background: There is no as such previous study that takes a glance on the perceptions of general public regarding effects of scaling. The objective of the study was to disregard the misconceptions about post-scaling sensitivity and tooth mobility, to disregard the belief that scaling’s purpose is to whiten the teeth and to figure out how much awareness is there in our society regarding scaling. There is no information regarding the misunderstanding of dental scaling. This study is conducted on general public in Pakistan. Methods: A cross-sectional survey conducted via a close ended questionnaire in the twin cities of Pakistan on a random sample of 238 individuals aged from 18 to 60 years age was conducted in April and May 2020. Results: According to the results,72.3% (172/238) participants were females and 27.7% (66/238) were males. More females had received scaling. 21-22 years age group had the highest scaling experience; also education level was related to scaling. About 87.4% (208/238) of the participants had received scaling once in their life, while 12.6% (30/238) had never experienced scaling. Of the subjects with complete data, 47.9% (114/238) got scaling done for teeth whitening, 39.9% (95/238) were advised scaling by their dentists before any procedure (braces, filing) and 12.2% (29/238) to reduce bleeding gums. Of those who had got scaling done, 44.1% (105/238) participants were scared before getting scaling done, 54.2% (129/238) individuals experienced pain and sensitivity during the procedure, 27.3% (65/238) individuals experienced sensitivity before scaling and 72.7% (173/238) had no sensitivity before the procedure. 56.3% (134/238) experienced sensitivity after getting scaling done, and for most of them this sensitivity was relieved within a week after treatment. 46.6% (111/238) individuals were told by their relatives and friends that scaling would increase their pain and loosen their teeth. 71.4% (170/238) patients were informed by their dentist that sensitivity is a normal part of recovery. 93.3% (222/238) patients found the treatment as beneficial and only 6.7% (16/238) marked it harmful. 92% (219/238) patients said that they would recommend scaling to others due to its beneficial effects. Conclusion: This study shows lack of knowledge regarding scaling among general population. The patients should be properly educated about the procedure and its effects, and clear all the misunderstandings, before the procedure. Keywords: Routine scaling and polishing; sensitivity; bleeding; periodontal disease

Resource Allocation in a National Dental Service Using Program Budgeting Marginal Analysis.

In any health system, choices must be made about the allocation of resources (budget), which are often scarce. Economics has defined frameworks to aid resource allocation, and program budgeting marginal analysis (PBMA) is one such framework. In principle, patient and public values can be incorporated into these frameworks, using techniques such as willingness to pay (WTP). However, this has not been done before, and few formal resource allocation processes have been undertaken in dentistry. This study aimed to undertake a PBMA with embedded WTP values in a national dental setting. The PBMA process was undertaken by a panel of participant-researchers representing commissioners, dentists, dental public health staff, and academics. The panel reviewed current allocations and generated a set of weighted criteria to evaluate services against. Services to be considered for removal and investment were determined by the panel and wider discussion and then scored against the criteria. Values from a nationally representative WTP survey of the public contributed to the scores for interventions. Final decisions on removal and investment were taken after panel discussion using individual anonymous electronic voting. The PBMA process resulted in recommendations to invest in new program components to improve access to general dentists, care home dentistry, and extra support for dental public health input into local government decisions. Disinvestments were recommended in orthodontics and to remove routine scaling and polishing of teeth. The PBMA process was successful in raising awareness of resource allocation issues. Implementation of findings will depend on the ability of decision makers to find ways of operationalizing the decisions. The process illustrates practical aspects of the process that future dental PBMAs could learn from. This study illustrates a framework for resource allocation in dental health services and will aid decision makers in implementing their own resource allocation systems.

Identifying periodontitis risk factors through a retrospective analysis of 80 cases.

ABSTRACTObjectives:To investigate periodontitis risk factors and to establish a reference framework for identifying factors that place individuals at greater risk for periodontitis.Methods:Clinical data from 80 periodontitis patients admitted in the Department of Stomatology at Hebei Provincial People’s Hospital and treated between March 2020 and March 2021 were retrospectively analyzed.Results:Univariate analysis showed that lower daily brushing frequencies, decreased tooth brushing duration, decreased scaling frequency, dietary habits, smoking and drinking, genetic factors, diabetes, hypertension, and obesity were more prevalent among periodontitis patients than healthy controls. Multivariate binary logistic analysis showed that daily brushing frequency, routine scaling, smoking, drinking, heredity, diabetes, hypertension, and obesity were all risk factors for periodontitis.Conclusions:There are many risk factors for periodontitis. Clinicians need to be aware of these factors for early detection and treatment of the disease.

The Effects of Prednisone/Ketoprofen Administration in Association with Amoxicillin Clavulanate Following Periodontal Surgical Therapy in Patients with Severe Chronic Periodontitis.

Background and Objectives: The aim of this study was to evaluate and compare the effects of two different anti-inflammatory drugs (ketoprofen and prednisone) combined with an antibiotic (amoxicillin + clavulanic acid) and periodontal surgery on dental and periodontal parameters in patients with severe chronic periodontitis. In addition, salivary stress expressed by cortisol levels was assessed. Materials and Methods: An interventional study was performed on 22 periodontal subjects and 19 clinical healthy controls. The patients were divided in four groups, depending on treatment planning, as follows: eight patients received prednisone and antibiotherapy, associated with surgical periodontal therapy; seven patients received ketoprofen and antibiotherapy, associated with surgical periodontal therapy (group II); seven patients received only prednisone. Periodontal healthy patients underwent routine scaling and polishing. Bleeding on probing (BOP), dental mobility and salivary cortisol (ng/mL) were assessed before and after treatment. The means and standard deviations for the salivary cortisol levels (SCLs), dental and periodontal parameters were calculated for all groups using each patient as a unit of analysis. Results: Data analyses showed that the two different anti-inflammatory drugs associated with or without surgical therapy were efficient on inflammation periodontal parameters (BOP, dental mobility). Prednisone treatment alone was associated with a significant decrease of SCLs between pretreatment and post-treatment. Conclusions: In the present study, the effects of either of the anti-inflammatory drugs on inflammation evolution and salivary stress were comparable in patients undergoing antibiotherapy and surgical periodontal therapy.

Nano-Bio Fusion Gingival Gel in the management of fixed orthodontic treatment-induced gingivitis: An empirical study

This research aimed to investigate the effect of Nano-Bio Fusion Gingival Gel ([NBFG] NanoCureTech, Gangdong-gu, Seoul, Korea) as an aid along with oral hygiene advice and routine scaling in patients with malocclusion to control treatment-induced gingivitis and periodontitis in patients undergoing fixed orthodontic treatment. A split-mouth design, prospective analysis after application of NBFG in 32 subjects with fixed orthodontic treatment-induced gingivitis was conducted. Patients applied NBFG to their gingiva twice daily, after brushing, for 90 consecutive days. Outcomes measured included: the plaque index (PI), papillary bleeding gingival index (PBI), probing depth (PD), and clinical attachment loss using standard assessment. PI, PBI, PD, and clinical attachment loss were measured at baseline, on the seventh day of gel application, at the next visit at the orthodontic clinic (28th day), and after 90days. From baseline to the seventh day to the 90th day, the treatment group showed significant improvement in PI, PBI, and PD over time compared with the placebogroup. NBFG showed positive clinical effects in patients undergoing fixed orthodontic treatment. Clinical outcomes were measured in a comparatively short period.

Thermoresponsive Hydrogel-Based Local Delivery of Simvastatin for the Treatment of Periodontitis.

Except for routine scaling and root planing, there are few effective nonsurgical therapeutic interventions for periodontitis and associated alveolar bone loss. Simvastatin (SIM), one of the 3-hydroxy-3-methylglutaryl-cosenzyme A reductase inhibitors, which is known for its capacity as a lipid-lowering medication, has been proven to be an effective anti-inflammatory and bone anabolic agent that has shown promising benefits in mitigating periodontal bone loss. The local delivery of SIM into the periodontal pocket, however, has been challenging due to SIM's poor water solubility and its lack of osteotropicity. To overcome these issues, we report a novel SIM formulation of a thermoresponsive, osteotropic, injectable hydrogel (PF127) based on pyrophosphorolated pluronic F127 (F127-PPi). After mixing F127-PPi with F127 at a 1:1 ratio, the resulting PF127 was used to dissolve free SIM to generate the SIM-loaded formulation. The thermoresponsive hydrogel's rheologic behavior, erosion and SIM release kinetics, osteotropic property, and biocompatibility were evaluated in vitro. The therapeutic efficacy of SIM-loaded PF127 hydrogel on periodontal bone preservation and inflammation resolution was validated in a ligature-induced periodontitis rat model. Given that SIM is already an approved medication for hyperlipidemia, the data presented here support the translational potential of the SIM-loaded PF127 hydrogel for better clinical management of periodontitis and associated pathologies.

Are We Causing Antibiotic Resistance with Antibiotic Abuse? A Study among Dentists

INTRODUCTION: With the invention of any new technology their comes the boon and curse both. The invention and use of antibiotics comes a problem of antibiotic resistance which is much more in extent than treating the infectious disease. Keeping this in mind the WHO in 2011 gave the theme “combat drug resistance- No action today, No cure tomorrow” which was very significant. The present study was done with the aim to know the prescription pattern of antibiotics for various dental procedures by dental practitioners.MATERIALS AND METHODS: A specially prepared questionnaire exclusively designed for the study recording all the required relevant general information and information related to antibiotic prescribing patterns was used for data collection. The questionnaire consisted of three sections. The first part of the questionnaire collected the demographic details of the study population like age, gender, Graduate or postgraduate degree, area of specialization and years of practice. In the second section the Questions related to antibiotics use in certain dental clinical procedures and conditions in apparently healthy people were asked from the participants. In the last section of the questionnaire the participants were asked about the questions related to antibiotics use for certain dental clinical procedures in medically compromised cases.RESULTS: Questionnaire response rate of 73% was recorded. The study showed Augmentin to be the first choice of antibiotic by most of the respondents. The study showed that 64% of the endodontists and 74% of the general dentists prescribed antibiotics during root canal therapy where ideally operative intervention would have sufficed. Overuse of antibiotics for routine scaling and extraction was observed.CONCLUSION: The dental profession as a whole needs to acquire a deeper understanding of the global effects of unnecessary antibiotic prescription. Antibiotics when judiciously used are precise life-saving drugs.

Professional oral prophylaxis: Assessment of practice by oral health professionals in Southeastern Nigeria

Background: Professional oral prophylaxis reduces plaque and calculus levels and improves oral health. This study identified the practice of routine scaling and polishing among oral health professionals. Methodology: This was a cross-sectional study of 73 oral health professionals who attended the Southeast Oral Health Forum at Onitsha, Anambra State, Nigeria. Data on sociodemographic profile, the undertaking of scaling and polishing of the teeth, reasons for the scaling and polishing, recommendation of scaling and polishing to their patients, and duration of recall were recorded. Data analysis was done using SPSS Version 21. The association between demographic profile and practice of scaling and polishing at 6 months' interval was tested using the Chi-square test at a significance level of P

Triphala: A phytomedicine for local drug delivery – A strategic intervention

Background:In the Indian system of medicine (ISM) Triphala is one of the oldest and longest used natural herbal remedy which consist of mixture of equal parts of the Embilica officinalis Gaertn. (Family- Euphorbiaceae), Terminalia Chebula Retz. (Family- Combretaceae) and Terminalia beleria [Gaertn.] Roxb. (Family- Combretaceae). Currently, Triphala is being extensively researched for its various therapeutic effects including its anti-caries, antioxidant, anti-collagenase and anti-microbial activities. This fruit extract is used in various forms in the treatment of periodontitis.Aim:The aim of the present study was to compare the clinical and microbiological benefits of routine scaling and root planing (SRP) with adjunctive use of Triphala (Hiora GA) as local drug delivery agent in the management of periodontitis.Materials and Methods:Thirteen patients diagnosed with chronic periodontitis were included in the present study. The control sites received SRP alone and the test sites received SRP with locally delivered Triphala (Hiora GA). The clinical parameters were evaluated at baseline, 15 days and 1 month. The plaque samples were cultured anaerobically for the keystone-periodontal pathogen Porphyromonas gingivalis, Fusobacterium nucleatum and Prevotella intermedia. The Mann–Whitney U-test and Wilcoxon signed-rank tests were performed to compare the results between the test and control groups.Results:Statistically significant improvement was observed in both groups. Intergroup comparison of prevalence of microorganisms also revealed a statistically significant difference (P = 0.0007) at 15 days and 1 month.Conclusion:Subgingivally delivered Triphala (Hiora GA) as an adjunct to SRP in the treatment of chronic periodontitis has shown anticipative results revealing slow and constant releasing property of Triphala.

Routine scale and polish for periodontal health in adults.

Routine scale and polish for periodontal health in adults.

Effect of routine scaling and prophylactic polishing on the surface roughness of nano-filled restorative materials: In vitro study

AimThis study aimed at investigating in vitro the effect of routine scaling (hand/ultrasonic) and polishing on the surface roughness of three nano-filled restorative materials. Materials and methodsNano-filled universal resin composite (Filtek Z350), nano-filled flowable resin campsite (Filtek Supreme Plus Flow) and resin modified glass ionomer (Ketac N100) were tested. Ninety discs (10 mm × 2 mm) were prepared and divided into 3 groups (n = 30/material). Each group was divided into 5 subgroups (n = 6). Subgroup 1: control (surface against matrix), subgroup 2: ultrasonically scaled (US), subgroup 3: hand scaled, subgroups 4 and 5 were US, hand scaled then received prophylactic polishing respectively. The mean surface roughness (Ra μm) of all specimens was measured by a profilometer. Data were statistically analyzed by ANOVA and post-hoc tests (P ≤ 0.05). Representative specimens were examined by the SEM. ResultsUnder all testing conditions, Ketac N showed the highest mean Ra value expect for hand scaled/non-polished specimens, where they were not significantly different than the Filtek Z350 as confirmed by SEM. However, under all testing conditions, Filtek Flow revealed the lowest mean Ra values except for polished specimens after either hand or US scaling; there was insignificant difference between Filtek Z350 and Filtek Flow. ConclusionsScaling method tends to have material dependent effect on the Ra. All polished material's Ra exceeded the critical threshold roughness values. Clinical significanceRoutine periodontal scaling and prophylactic polishing of nano-filled resin restorations should be carried out with caution. Nano-filled flowable resin composite can be recommended in Class V restorations.

Should fatty acid signature proportions sum to 1 for diet estimation?

AbstractKnowledge of predator diets, including how diets might change through time or differ among predators, provides essential insights into their ecology. Diet estimation therefore remains an active area of research within quantitative ecology. Quantitative fatty acid signature analysis (QFASA) is an increasingly common method of diet estimation. QFASA is based on a data library of prey signatures, which are vectors of proportions summarizing the fatty acid composition of lipids, and diet is estimated as the mixture of prey signatures that most closely approximates a predator's signature. Diets are typically estimated using proportions from a subset of all fatty acids that are known to be solely or largely influenced by diet. Given the subset of fatty acids selected, the current practice is to scale their proportions to sum to 1.0. However, scaling signature proportions has the potential to distort the structural relationships within a prey library and between predators and prey. To investigate that possibility, we compared the practice of scaling proportions with two alternatives and found that the traditional scaling can meaningfully bias diet estimators under some conditions. Two aspects of the prey types that contributed to a predator's diet influenced the magnitude of the bias: the degree to which the sums of unscaled proportions differed among prey types and the identifiability of prey types within the prey library. We caution investigators against the routine scaling of signature proportions in QFASA.

Microbiological Efficacy of Photodynamic Therapy as an Adjunct to Non-surgical Periodontal Treatment: A Clinical Trial.

The efficiency of routine scaling and root planning is negatively influenced by the tooth anatomy and residual bacteria all possibly affecting the treatment outcomes in future. The present study compared the microbiologic effectiveness of the photodynamic therapy (PDT) as an adjunctive treatment modality for nonsurgical treatment in chronic periodontitis. In this randomized controlled clinical trial, 18 chronic periodontitis patients were selected. Four quadrants were randomly treated by scaling and root planning (SRP), diode laser (810n m wavelength, 1.5 W and 320 μm fiber, contact and sweeping technique), SRP + PDT (with diode laser 808 nm, 0.5 W) and laser + SRP (with diode laser 808 nm, 1 W) in each patient. Presence of periodontal pathogen species in the treated areas were measured before the treatment, at 1 and 3 months afterwards. The identification and reproduction of the specific genes of pathogen bacteria were done by means of polymerase chain reaction (PCR) technique. Presence of oral pathogen bacteria in the treatment groups were analyzed by chi-square test. A semi quantitative analysis was used to measure the intensity of white light in each band. This was calculated by number of pixels in each band. In the qualitative analysis, Fusobacterium nucleatum (Fn) and Treponema denticola (Td) species were killed after 1 month in all treatment modalities. PDT had more effects to decrease Prevotella intermedia (Pi) species than SRP while Tannerella forsythensis count (Tf) species increased in all treatments. Furthermore, Actinobacillus actinomycetemcomitans (Aa) species decreased in all treatments and Porphyromonas gingivalis (P.g) species increased in all treatments after 1 and 3 months. It can be concluded that PDT was more effective as an adjunctive treatment to SRP than SRP alone; however, no distinct differences were found between both treatment modalities regarding reduction of certain pathogen bacteria.

Prevention and management of scale and polish damage to resin composite restorations.

Background The use of resin composite in the restoration of, in particular, posterior teeth is increasing. This trend is set to continue, with the momentum-gathering shift towards minimal-intervention direct approaches to the restoration of diseased, damaged and worn teeth, and subsequent to the signing of the Minamata Convention, aimed, amongst other measures, at ‘phasing down’ the use of dental amalgam.1–3 As a result, members of the dental team should, it is suggested, give consideration to the prevention and management of the damage that routine scaling and polishing may cause to the margins and surfaces of restorations of resin composite, or indeed restorations of other tooth-coloured restorative systems. Such damage may compromise the aesthetic qualities and reduce the life expectancy of tooth-coloured restorations. This article focuses on the prevention and management of scale and polish damage to resin composite restorations.

On the Axisymmetric Turbulent Boundary Layer Growth Along Long Thin Circular Cylinders

Even after several decades of experimental and numerical testing, our present-day knowledge of the axisymmetric turbulent boundary layer (TBL) along long thin circular cylinders still lacks a clear picture of many fundamental characteristics. The main issues causing this reside in the experimental testing complexities and the numerical simplifications. An important characteristic that is crucial for routine scaling is the boundary layer length scales, but the downstream growth of these scales (boundary layer, displacement, and momentum thicknesses) is largely unknown from the leading to trailing edges. Herein, we combine pertinent datasets with many complementary numerical computations (large-eddy simulations) to address this shortfall. We are particularly interested in expressing the length scales in terms of the radius-based and axial-based Reynolds numbers (Rea and Rex). Although the composite dataset gave an averaged shape factor H = 1.09 that is substantially lower than the planar value (H = 1.27), the shape factor distribution along the cylinder axis actually begins at the flat plate value then decays logarithmically to near unity. The integral length scales displayed power-law evolutions with variable exponents until high Rea (Rea &gt; 35,000) where both scales then mimic streamwise consistency. Beneath this threshold, their streamwise growth is much slower than the flat plate (especially at low-Rea). The boundary layer thickness grew according to an empirical expression that is dependent on both Rea and Rex where its streamwise growth can far exceed the planar turbulent flow. These unique characteristics rank the thin cylinder axisymmetric TBL as a separate canonical flow, which was well documented by the previous investigations.

Routine scale and polish for periodontal health in adults

Many dentists or hygienists provide scaling and polishing for patients at regular intervals, even if those patients are considered to be at low risk of developing periodontal disease. There is debate over the clinical effectiveness and cost effectiveness of 'routine scaling and polishing' and the 'optimal' frequency at which it should be provided.The main objectives were: to determine the beneficial and harmful effects of routine scaling and polishing for periodontal health; to determine the beneficial and harmful effects of providing routine scaling and polishing at different time intervals on periodontal health; to compare the effects of routine scaling and polishing provided by a dentist or professionals complementary to dentistry (PCD) (dental therapists or dental hygienists) on periodontal health.We searched the Cochrane Oral Health Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Reference lists from relevant articles were scanned and the authors of eligible studies were contacted where possible to identify trials and obtain additional information. Date of most recent searches: 5th March 2007.Trials were selected if they met the following criteria: design - random allocation of participants; participants - anyone with an erupted permanent dentition who were judged to have received a 'routine scale and polish' (as defined in this review); interventions - 'routine scale and polish' (as defined in this review) and routine scale and polish provided at different time intervals; outcomes - tooth loss, plaque, calculus, gingivitis, bleeding and periodontal indices, changes in probing depth, attachment change, patient-centred outcomes and economic outcomes.Information regarding methods, participants, interventions, outcome measures and results were independently extracted, in duplicate, by two review authors. Authors were contacted where possible and where deemed necessary for further details regarding study design and for data clarification. A quality assessment of all included trials was carried out. The Cochrane Collaboration's statistical guidelines were followed and both standardised mean differences and mean differences were calculated as appropriate using random-effects models.Nine studies were included in this review. All studies were assessed as having a high risk of bias.Two split-mouth studies provided data for the comparison between scale and polish versus no scale and polish. One study, involving patients attending a recall programme following periodontal treatment, found no statistically significant differences for plaque, gingivitis and attachment loss between experimental and control units at each time point during the 1 year trial. The other study, involving adolescents in a developing country with high existing levels of calculus who had not received any dental treatment for at least 5 years, reported statistically significant differences in calculus and gingivitis (bleeding) scores between treatment and control units at 6, 12 and 22 months (in favour of 'scale and polish units') following a single scale and polish provided at baseline to treatment units. For comparisons between routine scale and polish provided at different time intervals, there were some statistically significant differences in favour of scaling and polishing provided at more frequent intervals: 2 weeks versus 6 months, 2 weeks versus 12 months (for the outcomes plaque, gingivitis, pocket depth and attachment change); 3 months versus 12 months (for the outcomes plaque, calculus and gingivitis). There were no studies comparing the effects of scaling and polishing provided by dentists or professionals complementary to dentistry.The research evidence is of insufficient quality to reach any conclusions regarding the beneficial and adverse effects of routine scaling and polishing for periodontal health and regarding the effects of providing this intervention at different time intervals. High quality clinical trials are required to address the basic questions posed in this review.