Prevalence of dental caries in preschool children born preterm and/or with low birth weight: A systematic review with meta‐analysis of prevalence data

The aim of the present systematic review and meta‐analysis was to evaluate the prevalence of dental caries among preschool children who had been born preterm and/or with low birth weight (LBW) compared with those who had been born full term and/or with normal birth weight (NBW). Eight electronic databases were searched from interception up to November 2018 with no restrictions imposed regarding the date of publication or language. Two independent reviewers screened studies, extracted data, and assessed the risk of bias. A random‐effects meta‐analysis was run to pool the crude prevalence of dental caries according to gestational age and birth weight. We performed a narrative synthesis and assessed the certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Fifty‐nine observational studies were included (55 in the meta‐analysis). The prevalence of dental caries was 39% among preterm children, 30% among full‐term children, 40% among LBW children, and 33% among NBW children (I²:97%‐99%). The majority of studies reported that dental caries was not associated with gestational age or birth weight, with very low certainty of evidence. Preschool children born preterm or with LBW have similar dental caries experience as those born full term or with NBW, with very low certainty of evidence (PROSPERO #CDR42018118086).     

Prophylactic antibiotic regimen and dental implant failure: a meta‐analysis

The aim of this meta‐analysis was to investigate whether there are any positive effects of prophylactic antibiotic regimen on implant failure rates and post‐operative infection when performing dental implant treatment in healthy individuals. An electronic search without time or language restrictions was undertaken in March 2014. Eligibility criteria included clinical human studies, either randomised or not. The search strategy resulted in 14 publications. The I² statistic was used to express the percentage of the total variation across studies due to heterogeneity. The inverse variance method was used with a fixed‐ or random‐effects model, depending on the heterogeneity. The estimates of relative effect were expressed in risk ratio (RR) with 95% confidence interval. Six studies were judged to be at high risk of bias, whereas one study was considered at moderate risk, and six studies were considered at low risk of bias. The test for overall effect showed that the difference between the procedures (use versus non‐use of antibiotics) significantly affected the implant failure rates (P = 0·0002), with a RR of 0·55 (95% CI 0·41–0·75). The number needed to treat (NNT) to prevent one patient having an implant failure was 50 (95% CI 33–100). There were no apparent significant effects of prophylactic antibiotics on the occurrence of post‐operative infections in healthy patients receiving implants (P = 0·520). A sensitivity analysis did not reveal difference when studies judged as having high risk of bias were not considered. The results have to be interpreted with caution due to the presence of several confounding factors in the included studies.     

Technical quality of root canal treatment performed by undergraduate students using hand instrumentation: a meta‐analysis

The technical quality of root canal treatment (RCT) may impact on the outcome. The quality of education received during undergraduate school may be linked to the quality of treatment provided in general dental practice. In this context, the aim of this systematic review was to answer the following focused questions: (i) What is the frequency of acceptable technical quality of root fillings, assessed radiographically, performed by undergraduate students? (ii) What are the most common errors assessed radiographically and reported in these treatments? For this purpose, articles that evaluated the quality of root fillings performed by undergraduate students were selected. Data were collected based on predetermined criteria. The key features from the included studies were extracted. GRADE‐tool assessed the quality of the evidence. MAStARI evaluated the methodological quality, and a meta‐analysis on all studies was conducted. At the end of the screening, 24 articles were identified. Overall frequency of acceptable technical quality of root fillings was 48%. From this total, 52% related to anterior teeth, 49% to premolars and 26% to molars. The main procedural errors reported were ledge formation, furcation perforation, apical transportation and apical perforation. The heterogeneity amongst the studies was high (84–99%). Five studies had a high risk of bias, eight had a moderate risk, and 11 had low risk. The overall quality of evidence identified was very low. The conclusion was that technical quality of root fillings performed by undergraduate students is low, which may reveal that endodontic education has limited achievement at undergraduate level. A plan to improve the quality of root fillings, and by extrapolation the overall quality of root canal treatment, should be discussed by the staff responsible for endodontic education and training.     

Association between epilepsy and oral maxillofacial trauma: A systematic review and meta‐analysis

A systematic literature search was conducted (through April 2017), using Web of Science, PubMed and Virtual Health Library, manual reference list, and grey literature searches. The quality of the studies was evaluated using the Newcastle‐Ottawa Quality Assessment Scale. The meta‐analysis was performed using R software. A total of 30 studies was included in this review. From a total of 25 studies included in the meta‐analysis, the prevalence of oral and maxillofacial injuries among epileptic subjects was 19%. Among the epileptic patients who suffered some type of injury due to epileptic seizures, 52% had facial soft tissue injuries (95%CI: 28‐75%), 18% suffered dental trauma (95%CI: 11‐29%), and 12% (95%CI: 4‐28%) suffered maxillofacial fractures. Epileptic patients were more likely to have oral and maxillofacial injuries than healthy individuals (OR: 5.22, 95%CI: 2.84‐9.36) and subjects with psychogenic nonepileptic seizures (OR: 2.77, 95%CI: 1.28‐5.99), but not than patients with special needs (OR: 2.45,95%CI: 0.95‐6.31).     

Does computerized anaesthesia reduce pain during local anaesthesia in paediatric patients for dental treatment? A systematic review and meta‐analysis

This systematic review and meta‐analysis analysed whether pain and disruptive behaviour can be decreased by the use of computerized local dental anaesthesia (CDLA) in children. The literature was screened to select randomized clinical trials that compared computerized and conventional anaesthesia. The primary outcome was pain perception during anaesthesia; the secondary, disruptive behaviour. The risk of bias of individual papers and the quality of the evidence were evaluated. After search, 8389 records were found and 20 studies remained for the qualitative and quantitative syntheses. High heterogeneity was detected for both outcomes. For the pain perception, the overall analysis showed a standard mean difference of ?0.78 (?1.31, ?0.25) favouring CDLA; however, when only studies at low risk of bias were analysed (subgroup analysis), there was no difference between the two techniques [?0.12(?0.46, 0.22)]. For disruptive behaviour, no differences were detected for continuous [?0.26 (?0.68, 0.16)] or dichotomous data [0.81 (0.62, 1.06)]. The quality of evidence was judged as low for pain perception and very low for disruptive behaviour. It is concluded that there is no difference in the pain perception and disruptive behaviour in children subjected to computerized or conventional dental local anaesthesia. Notwithstanding, the quality of the available evidence is low.     

Meta‐Analysis of Association Between Interleukin‐1β C‐511T Polymorphism and Chronic Periodontitis Susceptibility

Background: Many studies have been conducted to explore the association between interleukin (IL)‐1β C‐511T polymorphism and risk of chronic periodontitis (CP) but with different or even contradictory results. A meta‐analysis was performed to further explore their association. Methods: PubMed, Chinese National Knowledge Infrastructure, and EMBASE were searched up to September 30, 2014 for relevant case‐control studies. Two authors (D‐YL and L‐YX) independently selected studies and extracted data from included studies. The meta‐analysis was performed using comprehensive meta‐analysis software. Results: Nineteen case‐control studies involving 2,173 patients with CP and 3,900 healthy controls were included. Using a random‐effects meta‐analysis model, a non‐significant association between IL‐1β C‐511T polymorphism and CP was identified (T versus C: odds ratio [OR] = 1.03, 95% confidence interval [CI] = 0.85 to 1.25; TT versus CC: OR = 1.03, 95% CI = 0.72 to 1.46; CT versus CC: OR = 0.96, 95% CI = 0.71 to 1.30; CT + TT versus CC: OR = 1.00, 95% CI = 0.74 to 1.34; TT versus CT + CC: OR = 1.05, 95% CI = 0.81 to 1.38), and sensitivity analysis indicated that the results were robust. Subgroup analyses also revealed a non‐significant association. No publication bias was detected. Conclusions: Based on currently available evidence, IL‐1β C‐511T polymorphism is not associated with the risk of developing CP. Additional research is warranted to further explore and confirm the association of genetic polymorphism and CP.     

The risk of moderate‐to‐severe post‐operative pain following the placement of dental implants

In recent years, the implant‐supported dentures have risen rapidly, and thus, more attention was paid to post‐operative pain, following dental implantation. To explore risk factors and establish as well as validate a risk prediction model for moderate‐to‐severe post‐operative pain following dental implantation. A observational study of 352 patients with 563 implants was carried out. The following candidate predictors were collected: age, gender, pain sensitivity, anxiety, pain expectation, operator experience, position, length and number of placed implants, duration of surgery and surgery procedures. The outcome was the presence of moderate‐to‐severe post‐operative pain within the 24 hours post‐surgery. Multivariate logistic regression in combination with bootstrapping techniques was used to explore independent risk factors and establish a prediction model. The mean pain intensity score was 4.21 within 24 hours post‐operatively, while the incidence of moderate‐to‐severe pain was 61.9%. Independent risk factors of moderate‐to‐severe post‐operative pain were flap surgery, surgical template, the interaction between anxiety state and pain sensitivity, the interaction between pain sensitivity and pain expectation and the interaction between implant length and immediate implant. The area under the receiver operator characteristic curve was 0.72. The model's sensitivity was 75.7%, and the specificity was 64.2%. The model reliability was good (Nagelkerke's R² 0.226). The risk factors and the prediction model (needs further improvement) can help dentists to identify patients at increased risk of moderate‐to‐severe post‐operative pain following dental implantation.     

Periodontal Disease and Incident Lung Cancer Risk: A Meta‐Analysis of Cohort Studies

Background: Periodontal disease is linked to a number of systemic diseases such as cardiovascular diseases and diabetes mellitus. Recent evidence has suggested periodontal disease might be associated with lung cancer. However, their precise relationship is yet to be explored. Hence, this study aims to investigate the association of periodontal disease and risk of incident lung cancer using a meta‐analytic approach. Methods: PubMed, Scopus, and ScienceDirect were searched up to June 10, 2015. Cohort and nested case‐control studies investigating risk of lung cancer in patients with periodontal disease were included. Hazard ratios (HRs) were calculated, as were their 95% confidence intervals (CIs) using a fixed‐effect inverse‐variance model. Statistical heterogeneity was explored using the Q test as well as the I² statistic. Publication bias was assessed by visual inspection of funnel plots symmetry and Egger’s test. Results: Five cohort studies were included, involving 321,420 participants in this meta‐analysis. Summary estimates based on adjusted data showed that periodontal disease was associated with a significant risk of lung cancer (HR = 1.24, 95% CI = 1.13 to 1.36; I² = 30%). No publication bias was detected. Subgroup analysis indicated that the association of periodontal disease and lung cancer remained significant in the female population. Conclusion: Evidence from cohort studies suggests that patients with periodontal disease are at increased risk of developing lung cancer.     

Graft‐Free Maxillary Sinus Floor Elevation: A Systematic Review and Meta‐Analysis

Background: This systematic review and meta‐analysis aims to investigate survival rates of dental implants placed simultaneously with graft‐free maxillary sinus floor elevation (GFSFE). Factors influencing amount of vertical bone gain (VBG), protruded implant length (PIL) in sinus at follow‐up (PILf), and peri‐implant marginal bone loss (MBL) are also evaluated. Methods: Electronic and manual searches for human clinical studies on simultaneous implant placement and GFSFE using the lateral window or transcrestal approach, published in the English language from January 1976 to March 2016, were conducted. The random‐effects model and mixed‐effect meta‐regression were used to analyze weighted mean values of clinical parameters and evaluate factors that influenced amount of VBG. Results: Of 740 studies, 22 clinical studies were included in this systematic review. A total of 864 implants were placed simultaneously with GFSFE at edentulous sites having mean residual bone height of 5.7 ± 1.7 mm. Mean implant survival rate (ISR) was 97.9% ± 0.02% (range: 93.5% to 100%). Weighted mean MBL was 0.91 ± 0.11 mm, and it was significantly associated with the postoperative follow‐up period (r = 0.02; R² = 43.75%). Weighted mean VBG was 3.8 ± 0.34 mm, and this parameter was affected significantly by surgical approach, implant length, and PIL immediately after surgery (PILi) (r = 2.82, 0.57, 0.80; R² = 19.10%, 39.27%, 83.92%, respectively). Weighted mean PILf was 1.26 ± 0.33 mm (range: 0.3 to 2.1 mm). Conclusion: Within limitations of the present systematic review, GFSFE with simultaneous implant placement can achieve satisfactory mean ISR of 97.9% ± 0.02%.     

Oral health status of New Hampshire Head Start children, 2007‐2008

Objectives: We report on the baseline prevalence and severity of dental caries of children enrolled in the New Hampshire Head Start program during the 2007‐2008 school year. Methods: We selected a random cluster sample of 607 children aged 3‐5 years attending 27 Head Start centers across the state. Four volunteer dentists provided oral examinations and determined the presence of untreated dental caries, caries experience, and treatment urgency. Results: Overall, 40 percent of the participating children had experienced dental caries, and 31 percent had at least one untreated decayed tooth. Approximately 22 percent of the children had evidence of maxillary anterior caries, 23 percent were in need of dental care, and <1 percent needed urgent care. Conclusions: The prevalence of dental caries is comparable with that reported by Head Start programs elsewhere. The prevalence of caries affecting maxillary anterior teeth is higher. Further studies should examine state‐specific barriers to dental care among this population.     

Evaluation of plasma treatment effects on improving adhesive–dentin bonding by using the same tooth controls and varying cross‐sectional surface areas

The objective of this study was to evaluate and verify the effectiveness of plasma treatment for improving adhesive–dentin interfacial bonding by performing microtensile bond‐strength (μTBS) testing using the same‐tooth controls and varying cross‐sectional surface areas. Extracted unerupted human third molars were used after removal of the crowns to expose the dentin surface. One half of each dentin surface was treated with a non‐thermal argon plasma brush, whilst the other was shielded with glass slide and used as an untreated control. Adper Single Bond Plus adhesive and Filtek Z250 dental composite were then applied as directed. The teeth thus prepared were further cut into micro‐bar specimens, with cross‐sectional sizes of 1 × 1 mm², 1 × 2 mm², and 1 × 3 mm², for μTBS testing. The test results showed that plasma‐treated specimens gave substantially stronger adhesive–dentin bonding than their corresponding same‐tooth controls. Compared with their untreated controls, plasma treatment gave statistically significant higher bonding strength for specimens with a cross‐sectional area of 1 × 1 mm² and 1 × 2 mm², with mean increases of 30.8% and 45.1%, respectively. Interface examination using optical and electron microscopy verified that plasma treatment improved the quality of the adhesive–dentin interface by reducing defects/voids and increasing the resin tag length in dentin tubules.     

Risk of Implant Failure and Marginal Bone Loss in Subjects with a History of Periodontitis: A Systematic Review and Meta‐Analysis

Background: A number of studies have suggested that implant failure and associated bone loss is greater in subjects with a history of periodontitis. Purpose: To evaluate the risk for marginal bone loss around implants and implant failure in subjects with a history of periodontitis compared with periodontally healthy subjects in studies with a minimum 3‐year follow‐up. Materials and Methods: Data sources: The MEDLINE, EMBASE, and PubMed databases and relevant journals were searched up to July 1, 2008, with restriction to English language. Review Methods: Prospective and retrospective longitudinal observational clinical studies comparing periodontal/peri‐implant variables among subjects with periodontitis and subjects who were periodontally healthy were included. Screening of studies, quality assessment, and data extraction were conducted independently and in duplicate. Clarification of missing and unclear information was not sought. Outcome measures were: implant survival/failure, peri‐implant parameters, changes in radiographic marginal bone level, probing pocket depth, and gingival index. Results: Seventeen potential studies were identified and six studies were accepted comparing patients with periodontitis and periodontally healthy patients treated with implants. Five studies were eligible for meta‐analysis of implant survival and four studies were eligible for meta‐analysis of bone loss around implants. The odds ratio for implant survival was significantly in favor of periodontally healthy patients (3.02, 95% confidence intervals 1.12–8.15). A random effects model showed more marginal bone loss in periodontitis subjects compared with periodontally healthy subjects (standard mean difference 0.61, 95% confidence interval 0.14–1.09). Conclusions: Within the limitations of the heterogenous studies available, a moderate level of evidence indicates that periodontitis subjects were at significantly higher risk for implant failure and greater marginal bone loss as compared with periodontally healthy subjects. Prospective observational studies with subject‐based designs are recommended.     

Network Meta‐Analysis for Evaluating Interventions in Implant Dentistry: The Case of Peri‐Implantitis Treatment

Background/Aim: Evidence from head‐to‐head comparison trials on peri‐implantitis treatment is limited, and it is therefore impossible to conduct a direct meta‐analysis. We propose an alternative statistical method, network meta‐analysis, for evidence synthesis, which enables to compare the results of multiple treatments. Methods: We searched, in triplicate, for randomized controlled trials (RCTs) and controlled trials in the PubMed, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and Latin American and Caribbean Health Sciences Literature databases up to and including August 2010. We also conducted a manual search of the reference lists regarding published systematic reviews and searched for gray literature in OpenSIGLE. We assessed changes in clinical attachment level (CAL) and pocket probing depth (PPD) after nonsurgical and surgical treatments of peri‐implantitis. The risk of bias of selected studies was determined by the use of specific criteria, and it was performed in triplicate and independently. We used multilevel mixed modeling to perform the network meta‐analysis and Markov Chain Monte Carlo simulation to obtain confidence intervals for the fixed and random effects. Results: Eleven studies were included in the review. All RCTs are at unclear or high risk of bias. Surgical therapy in conjunction with bone grafts and non‐resorbable membranes achieved 3.52 mm greater PPD reduction than nonsurgical therapy alone, 95% high‐probability density (HPD) intervals: ?0.19, 6.81. Surgical treatment in conjunction with bone grafts and resorbable membranes achieved 2.80 mm greater CAL gain than nonsurgical therapy alone, 95% HPD intervals: ?0.18, 5.59. Conclusion: Surgical procedures in peri‐implantitis treatment achieve more PPD reduction and CAL gain than nonsurgical approaches. Nevertheless, these results should be interpreted with caution because of the limited number of studies included and their low methodological quality. Network meta‐analysis is a useful statistical methodology for evidence synthesis and to summarize the strength and limitation in the current evidence.     

Risk factors for impaired oral health among 18‐ to 34‐year‐old Australians

Objectives: The objective of this study was to determine risk factors for a summary measure of oral health impairment among 18‐ to 34‐year‐olds in Australia. Methods: Data were from Australia's National Survey of Adult Oral Health, a representative survey that utilized a three‐stage, stratified, clustered sampling design. Oral health impairment was defined as reported experience of toothache, poor dental appearance, or food avoidance in the last 12 months. Multivariate Poisson regression models were used to evaluate effects of sociodemographic characteristics, self‐perceived oral health, dental service utilization, and clinical oral disease indicators on oral health impairments. Effects were quantified as prevalence ratios (PR). Results: The estimated percent of 18‐ to 34‐year‐olds with oral health impairment was 42.4 [95 percent confidence interval (CI) 37.7‐47.2]. In the multivariate model, oral health impairment was associated with untreated dental decay (PR 1.38, 95 percent CI 1.13‐1.68) and presence of periodontal pockets 4 mm+ (PR 1.29, 95 percent CI 1.03‐1.61). In addition to those clinical indicators, greater prevalence of oral health impairment was associated with trouble paying a $100 dental bill (PR 1.37, 95 percent CI 1.12‐1.68), usually visiting a dentist because of a dental problem (PR 1.46, 95 percent CI 1.15‐1.86), reported cost barriers to dental care (PR 1.46, 95 percent CI 1.16‐1.85), and dental fear (PR 1.43, 95 percent CI 1.18‐1.73). Conclusions: Oral health impairment was highly prevalent in this population. The findings suggest that treatment of dental disease, reduction of financial barriers to dental care, and control of dental fear are needed to reduce oral health impairment among Australian young adults.     

Meta‐research publications in dentistry: a review

The present scoping review has the objective of providing an overview of meta‐research in dentistry. A search of the PubMed database was performed for the period 11 October 2014 to 10 October 2019. Study selection and data extraction were performed independently by one author; prior to this, a random sample of 10% of the retrieved titles and abstracts were independently screened by two authors, achieving agreement of >80% on eligibility for initial inclusion, corresponding to good agreement. The following information was extracted from the full text of each article: meta‐research area of interest; study design; type of studies evaluated in the meta‐research; type of methodology used in assessment of the primary research; conflicts of interest reported; sponsorships reported; dental discipline; journal of publication; country of the first author; number of citations; and impact factor. A total of 7800 documents were initially retrieved. After analysis of the title/abstract and the full text of each article, and a snowballing procedure, 155 meta‐research studies were identified and included. The ‘methods’ and ‘reporting’ meta‐research areas were the most prevalent, with 73 (47%) and 61 (40%) studies, respectively. General dentistry, and orthodontics and dentofacial orthopaedics were the dental specialties with the greatest number/proportion of included studies with 45 (29%) and 28 (18%) studies, respectively. These findings may help to prioritize future meta‐research in dentistry, consequently avoiding unnessecary investigations, and increasing the value of oral and dental research.     

Effect of occlusal reduction on postendodontic pain: A systematic review and meta‐analysis of randomised clinical trials

The purpose of this systematic review was to assess the effect of occlusal reduction on post‐operative pain following root canal treatment and was performed in accordance with the PRISMA statement being registered in the PROSPERO database (CRD42018089941). Two reviewers independently conducted a systematic literature search in the PubMed (MEDLINE), Dentistry & Oral Sciences Source and the Cochrane Library databases. Seven studies were included, of which three were used to perform meta‐analysis for 6 days post‐operative and the rest for qualitative synthesis. Three studies were assessed as low risk of bias, three as some concern, and one as high risk of bias. Occlusal reduction diminishes the post‐operative pain (SMD ?1.10 (95%CI ?2.06, ?0.15) I² = 96.9%) at 6 days for teeth diagnosed as irreversible pulpitis, and, overall, likely reduces post‐operative pain for patients presenting with irreversible pulpitis and/or symptomatic apical periodontitis. Future high‐quality clinical trials are needed to better understand the role of occlusal reduction.     

The One Abutment–One Time Protocol: A Systematic Review and Meta‐Analysis

Background: The use of definitive abutments (DAs) at time of implant placement has been introduced to overcome limitations of dis/reconnection of healing/provisional abutments (PAs). With little and inconsistent information in the literature regarding the effectiveness of using DAs, the aim of this systematic review is to examine marginal bone and soft tissue level changes, technical and biologic complications, and implant failure rate associated with use of DAs and PAs. Methods: This systematic review was prepared according to guidelines of the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and online trial registers were searched for studies comparing use of DAs and PAs. The Cochrane Collaboration risk of bias tool was used to assess selected studies, and meta‐analyses were performed using statistical software. Results: A total of 1,124 citations were identified. Of these, seven trials with 363 dental implants in 262 participants were included in the analysis. Pooled estimates for marginal bone level changes showed significant differences between the two prosthetic techniques in favor of using DAs. No significant differences were found in soft tissue level changes, technical and biologic complications, or implant failure rate. Conclusions: Within the limitations of this review, DAs appear to be a viable alternative to PAs at time of implant placement. However, favorable changes in peri‐implant marginal bone level associated with use of DAs should be viewed with caution as its clinical significance is still uncertain.     

Epidemiology and risk factors of peri‐implantitis: A systematic review

The purpose of this systematic review and meta‐analysis was to assess the prevalence, incidence and risk factors of peri‐implantitis in the current literature. An electronic search was performed to identify publications from January 1980 until March 2016 on 9 databases. The prevalence and incidence of peri‐implantitis were assessed in different subgroups of patients and the prevalences were adjusted for sample size (SSA) of studies. For 12 of 111 identified putative risk factors and risk indicators, forest plots were created. Heterogeneity analysis and random effect meta‐analysis were performed for selected potential risk factors of peri‐implantitis. The search retrieved 8357 potentially relevant studies. Fifty‐seven studies were included in the systematic review. Overall, the prevalence of peri‐implantitis on implant level ranged from 1.1% to 85.0% and the incidence from 0.4% within 3 years, to 43.9% within 5 years, respectively. The median prevalence of peri‐implantitis was 9.0% (SSA 10.9%) for regular participants of a prophylaxis program, 18.8% (SSA 8.8%) for patients without regular preventive maintenance, 11.0% (SSA 7.4%) for non‐smokers, 7.0% (SSA 7.0%) among patients representing the general population, 9.6% (SSA 9.6%) for patients provided with fixed partial dentures, 14.3% (SSA 9.8%) for subjects with a history of periodontitis, 26.0% (SSA 28.8%) for patients with implant function time ≥5 years and 21.2% (SSA 38.4%) for ≥10 years. On a medium and medium‐high level of evidence, smoking (effect summary OR 1.7, 95% CI 1.25‐2.3), diabetes mellitus (effect summary OR 2.5; 95% CI 1.4‐4.5), lack of prophylaxis and history or presence of periodontitis were identified as risk factors of peri‐implantitis. There is medium‐high evidence that patient’s age (effect summary OR 1.0, 95% CI 0.87‐1.16), gender and maxillary implants are not related to peri‐implantitis. Currently, there is no convincing or low evidence available that identifies osteoporosis, absence of keratinized mucosa, implant surface characteristics or edentulism as risk factors for peri‐implantitis. Based on the data analyzed in this systematic review, insufficient high‐quality evidence is available to the research question. Future studies of prospective, randomized and controlled type including sufficient sample sizes are needed. The application of consistent diagnostic criteria (eg, according to the latest definition by the European Workshop on Periodontology) is particularly important. Very few studies evaluated the incidence of peri‐implantitis; however, this study design may contribute to examine further the potential risk factors.     

The Effect of Coating Patterns with Spinel‐Based Investment on the Castability and Porosity of Titanium Cast into Three Phosphate‐Bonded Investments

Purpose: This study evaluated the effect of pattern coating with spinel‐based investment Rematitan Ultra (RU) on the castability and internal porosity of commercially pure (CP) titanium invested into phosphate‐bonded investments. The apparent porosity of the investment was also measured. Materials and Methods: Square patterns (15 × 15 × 0.3 mm³) were either coated with RU, or not and invested into the phosphate‐bonded investments: Rematitan Plus (RP), Rema Exakt (RE), Castorit Super C (CA), and RU (control group). The castings were made in an Ar‐arc vacuum‐pressure machine. The castability area (mm²) was measured by an image‐analysis system (n = 10). For internal porosity, the casting (12 × 12 × 2 mm³) was studied by the X‐ray method, and the projected porous area percentage was measured by an image‐analysis system (n = 10). The apparent porosity of the investment (n = 10) was measured in accordance with the ASTM C373‐88 standard. Results: Analysis of variance (One‐way ANOVA) of castability was significant, and the Tukey test indicated that RU had the highest mean but the investing technique with coating increased the castability for all phosphate‐bonded investments. The analysis of the internal porosity of the cast by the nonparametric test demonstrated that the RP, RE, and CA with coating and RP without coating did not differ from the control group (RU), while the CA and RE casts without coating were more porous. The one‐way ANOVA of apparent porosity of the investment was significant, and the Tukey test showed that the means of RU (36.10%) and CA (37.22%) were higher than those of RP (25.91%) and RE (26.02%). Conclusion: Pattern coating with spinel‐based material prior to phosphate‐bonded investments can influence the castability and the internal porosity of CP Ti.     

Soft tissue changes following extraction vs. nonextraction orthodontic fixed appliance treatment: a systematic review and meta‐analysis

The aim of this systematic review was to assess the effect of systematic extraction protocols during orthodontic fixed appliance treatment on the soft tissue profile of human patients. Nine databases were searched until December 2016 for controlled clinical studies including premolar extraction or nonextraction treatment. After elimination of duplicate studies, data extraction, and risk‐of‐bias assessment according to the Cochrane guidelines, random‐effects meta‐analyses of mean differences (MD) or standardized mean differences (SMD) and their 95% CIs were performed, followed by subgroup, meta‐regression, and sensitivity analyses. Extraction treatment was associated with increased lower lip retraction (24 studies; 1,456 patients; MD = 1.96 mm), upper lip retraction (21 studies; 1,149 patients; MD = 1.26 mm), nasolabial angle (21 studies; 1,089 patients; MD = 4.21°), soft‐tissue profile convexity (six studies; 408 patients; MD = 1.24°), and profile pleasantness (three studies; 249 patients; SMD = 0.41). Patient age, extraction protocol, and amount of upper incisor retraction during treatment were significantly associated with the observed extraction effects, while the quality of evidence was very low in all cases due to risk of bias, baseline confounding, inconsistency, and imprecision. Although tooth extractions seem to affect patient profile, existing studies are heterogenous and no consistent predictions of profile response can be made.