RinshoTrial mobile app: evidence-base dissemination tool

The clinical evidence-base of dental products and the “RinshoTrial” app as dissemination tool

By Prof Steffen Mickenautsch, BDS, PhD

ABSTRACT 

Introduction

Prospective, controlled clinical trials avoid the pitfalls of uncontrolled and/or retrospective studies. 

Aims and objectives

To conduct systematic literature searches for prospective, controlled clinical trials concerning dental products and disseminate results through a smartphone app.

Methods

Databases were searched. Reference lists were checked.  Trial selection criteria were: prospective, controlled clinical trial design; report published 1990 or later; product names reported in trial. From the accepted trials data points were extracted per product, including: full publication reference, city of first author’s affiliation. Data was made accessible as app for Android 5.0 and iOS smartphones. 

Results

1685 data points for 446 products were found for caries preventive / remineralization products, dental filling materials, fissure sealant materials. The results were presented through the RinshoTrial app, available on Google’s Play Store and Apple’s App Store. 

Conclusion

RinshoTrial may assist in the dissemination of commercial product specific prospective, controlled clinical trial references. It generates easy usable reference lists, as well as maps concerning the location of research centers, worldwide. Reference list and maps can be emailed and shared on social media from the app, directly. RinshoTrial gives no indication for trial quality and can only be a supportive tool prior trial appraisal.

Keywords:

Prospective, controlled clinical trials, oral health care products, RinshoTrial.

INTRODUCTION

Belief about the effectiveness of dental products may be supported by many sources: research trials of any type or design, expert opinion or own anecdotal experiences. Whether such belief reflects reality is a matter of whether such sources are valid.  The validity of (and thus the ability to generalise from) expert opinion or own anecdotal experiences has been questioned ^1,2 and the validity of laboratory-based studies has been shown not to reflect clinical reality.³ Hence, the need for clinical trials as evidence-base for therapeutic oral health care products has been emphasized.⁴

However, the validity of clinical trials depends largely on the characteristics of their applied study method, such as whether trials include a comparison against a control intervention and whether they measure therapeutic effects in time (prospectively) or in the past (retrospectively). Retrospective, controlled clinical trials may provide valuable estimates about rare risk factors where prospective trials are not feasible⁵ but unlike prospective, controlled clinical trials they can only be observational and thus carry a high risk of bias.⁶ Uncontrolled clinical trials, even when prospective, simply lack a benchmark or standard against which test treatment results can be compared. For that reason, the causal relationship of intervention characteristics to intervention outcome is uncertain.⁷ Therefore, any judgement based on uncontrolled trials about treatment effectiveness will be arbitrary, since it is not clear whether any other intervention, may it be a placebo or a gold standard treatment, would have yielded the same result in the selected patient cohort. Against such background, it may be concluded that any belief about the effectiveness of commercial dental products should at minimum be based on results from prospective, controlled clinical trials. Of course, results of such trials may still be misleading for many other reasons that are subject to trial appraisal in systematic reviews.⁸

Nonetheless, prospective, controlled clinical trials do at least avoid the pitfalls of uncontrolled and/or retrospective study designs. Hence, the identification of such trials provides an important first step when questioning the evidence-base of any dental product. Dissemination of such information to dental academia with interest e.g. in potential therapeutic gold-standards for future clinical trials, or to oral health care providers with interest in questioning current products on the market, may be assisted through simple online tools such as smartphone apps. One of such app is “RinshoTrial” (Figure 1) available on Google’s Play Store and Apple’s App Store (Figure 2). 

MATERIALS AND METHODS

The RinshoTrial app has been conceptionalized and developed by the author in 2019. The app has a free 3-day try-out period and is available thereafter on a 12-month subscription basis for a low annual fee. The app is neither sponsored nor supported by any product manufacturer or related interest group and, in order to retain its editorial independence, is financed solely through its subscription-user base. 

App functions

The app provides a search function for dental products. Products can be searched by name and yield per product a map of geographical locations where prospective, controlled clinical trials were conducted in the world, as well as a full reference list of the published trials reports (Figure 1). In addition, the app allows email forwarding and social media sharing of both maps and lists. The app also provides a function for users to request further information about any product’s evidence-base. The app data for oral health care products is regularly updated (at least once per year) and extended. Updates can be followed through a dedicated online blog.⁹

Systematic literature search

The author conducted systematic literature searches in the databases PubMed, DOAJ, LILACS, IndMed, CNKI and GoogleScholar for published clinical trials and systematic review reports to selecteded product categories without limitations regarding the publication language. Publications in non-English language were translated preliminary with the GoogleTranslate online tool¹⁰ and further in depth with the help of translators. The systematic review reports were traced in full copy and references of included/excluded trial reports extracted. The cut-off dates, trial selection criteria, searched databases and strings of search terms per systematic review were recorded in MS Excel. Subsequent systematic literature search updates from the recorded search cut-off date until 2019 were conducted for some of the included systematic reviews. The reference lists of all identified trial reports were checked for possible further relevant studies. 

Trial selection criteria were: prospective, controlled clinical trial design; trial report published 1990 or later; product names reported in study. From the accepted trial reports data points were extracted, per product name and product category. Each data point comprises of: Name of authors, report title, journal name, publication year, journal volume, first page number; city of first author’s academic affiliation. All data points were entered in Unicode Text-format into the app’s backend portal and made accessible through the app on Android 5.0 or iOS based smartphones. 

RESULTS

The systematic literature search identified a total of 1685 data points for 446 products in the product categories:  Caries preventive products/ remineralization products; Dental filling materials and Fissure sealant materials (Table 1). 

Table 1. Identified data points per products and oral health care topics

Product categories	Caries preventive & tooth remineralization products	Fissure sealant materials	Dental filling materials
Number of products	67	77	302
Data points	225	267	1193

Caries preventive and tooth remineralization products

PubMed was searched on the 10 November 2018 using the string of search terms: (remineralization OR remineralization) OR “Tooth Remineralization”[Mesh] AND (“Dental Enamel”[Mesh] OR enamel) and the following set search limits: Article types: Clinical study, clinical trial, pragmatic clinical trial, randomised controlled trial, systematic reviews, meta-analysis. In total, 218 trial reports and 35 systematic reviews (Table 2) of clinical trials were found. Of the systematic reviews, 20 were further updated in 2019. From the original database search, reference checks of the systematic review reports and their updates, a total of 425 trial reports could be included for review. Of these, 182 trial reports were found in line with the selection criteria and accepted for data extraction (Figure 3). A total of 225 data points, were extracted from the accepted trial reports concerning 67 caries preventive and tooth remineralizing products.

Table 2. Caries preventive and tooth remineralization products: Included published systematic reviews

Systematic review reports	Date of most recent update
1	Marinho VC, Higgins JP, Logan S, Sheiham A. Topical fluoride (toothpastes, mouthrinses, gels or varnishes) for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2003;(4):CD002782.	16.06.2019
2	Tubert-Jeannin S, Auclair C, Amsallem E, Tramini P, Gerbaud L, Ruffieux C, Schulte AG, Koch MJ, Rège-Walther M, Ismail A. Fluoride supplements (tablets, drops, lozenges or chewing gums) for preventing dental caries in children. Cochrane Database Syst Rev. 2011 Dec 7;(12):CD007592.	12.10.2011*
3	Marinho VC, Worthington HV, Walsh T, Clarkson JE. Fluoride varnishes for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2013 Jul 11;(7):CD002279.	13.05.2013*
4	Benson PE, Parkin N, Dyer F, Millett DT, Furness S, Germain P. Fluorides for the prevention of early tooth decay (demineralised white lesions) during fixed brace treatment. Cochrane Database Syst Rev. 2013 Dec 12;(12):CD003809.	31.01.2013*
5	Marinho VC, Worthington HV, Walsh T, Chong LY. Fluoride gels for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2015 Jun 15;(6):CD002280.	22.04.2016*
6	Walsh T, Oliveira-Neto JM, Moore D. Chlorhexidine treatment for the prevention of dental caries in children and adolescents. Cochrane Database Syst Rev. 2015 Apr 13;(4):CD008457.	25.02.2015*
7	Riley P, Moore D, Ahmed F, Sharif MO, Worthington HV. Xylitol-containing products for preventing dental caries in children and adults. Cochrane Database Syst Rev. 2015 Mar 26;(3):CD010743.	14.08.2014*
8	Ahovuo-Saloranta A, Forss H, Hiiri A, Nordblad A, Mäkelä M. Pit and fissure sealants versus fluoride varnishes for preventing dental decay in the permanent teeth of children and adolescents. Cochrane Database Syst Rev. 2016 Jan 18;(1):CD003067.	18.12.2015*
9	Takahashi R, Ota E, Hoshi K, Naito T, Toyoshima Y, Yuasa H, Mori R, Nango E. Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing dental caries in the primary teeth of their children. Cochrane Database Syst Rev. 2017 Oct 23;10:CD011850.	25.01.2017*
10	Duangthip D, Jiang M, Chu CH, Lo EC. Non-surgical treatment of dentin caries in preschool children–systematic review. BMC Oral Health. 2015 Apr 3;15:44.	09.07.2019
11	Okada EM, Ribeiro LN, Stuani MB, Borsatto MC, Fidalgo TK, Paula-Silva FW, Küchler EC. Effects of chlorhexidine varnish on caries during orthodontic treatment: a systematic review and meta-analysis. Braz Oral Res. 2016 Nov 28;30(1):e115.	11.07.2019
12	Derks A, Katsaros C, Frencken JE, van’t Hof MA, Kuijpers-Jagtman AM. Caries-inhibiting effect of preventive measures during orthodontic treatment with fixed appliances. A systematic review. Caries Res. 2004 Sep-Oct;38(5):413-20.	19.06.2019
13	James P, Parnell C, Whelton H. The caries-preventive effect of chlorhexidine varnish in children and adolescents: a systematic review. Caries Res. 2010;44(4):333-40.	24.06.2019
14	Slot DE, Vaandrager NC, Van Loveren C, Van Palenstein Helderman WH, Van der Weijden GA. The effect of chlorhexidine varnish on root caries: a systematic review. Caries Res. 2011;45(2):162-73.	24.06.2019
15	Zhang Q, van Palenstein Helderman WH, van’t Hof MA, Truin GJ. Chlorhexidine varnish for preventing dental caries in children, adolescents and young adults: a systematic review. Eur J Oral Sci. 2006 Dec;114(6):449-55.	20.06.2019
16	Mickenautsch S, Yengopal V. Anticariogenic effect of xylitol versus fluoride -a quantitative systematic review of clinical trials. Int Dent J. 2012 Feb;62(1):6-20.	03.07.2019
17	Mickenautsch S, Yengopal V. Effect of xylitol versus sorbitol: a quantitative  systematic review of clinical trials. Int Dent J. 2012 Aug;62(4):175-88.	05.07.2019
18	Tang X, Sensat ML, Stoltenberg JL. The antimicrobial effect of chlorhexidine varnish on mutans streptococci in patients with fixed orthodontic appliances: a systematic review of clinical efficacy. Int J Dent Hyg. 2016 Feb;14(1):53-61.	10.07.2019
19	Wierichs RJ, Meyer-Lueckel H. Systematic review on noninvasive treatment of root caries lesions. J Dent Res. 2015 Feb;94(2):261-71.	01.05.2014*
20	Janakiram C, Deepan Kumar CV, Joseph J. Xylitol in preventing dental caries: A systematic review and meta-analyses. J Nat Sci Biol Med. 2017 Jan-Jun;8(1):16-21.	10.07.2019
21	Freires IA, Denny C, Benso B, de Alencar SM, Rosalen PL. Antibacterial Activity of Essential Oils and Their Isolated Constituents against Cariogenic Bacteria: A Systematic Review. Molecules. 2015 Apr 22;20(4):7329-58.	10.07.2019
22	Abdullah Z, John J. Minimally Invasive Treatment of White Spot Lesions—A Systematic Review. Oral Health Prev Dent. 2016;14(3):197-205.	01.06.2014*
23	Azarpazhooh A, Main PA. Fluoride varnish in the prevention of dental caries in children and adolescents: a systematic review. J Can Dent Assoc. 2008 Feb;74(1):73-9.	01.01.2007*
24	Indrapriyadharshini K, Madan Kumar PD, Sharma K, Iyer K. Remineralizing potential of CPP-ACP in white spot lesions – A systematic review. Indian J Dent Res. 2018 Jul-Aug;29(4):487-496.	11.07.2019
25	Xiaotong W, Nanquan R, Jing X, Yuming Z, Lihong G. [Remineralization effect of casein phosphopeptide-amorphous calcium phosphate for enamel demineralization: a system review]. Hua Xi Kou Qiang Yi Xue Za Zhi. 2017 Dec 1;35(6):629-635.	12.07.2019
26	Höchli D, Hersberger-Zurfluh M, Papageorgiou SN, Eliades T. Interventions for orthodontically induced white spot lesions: a systematic review and meta-analysis. Eur J Orthod. 2017 Apr 1;39(2):122-133.	11.07.2019
27	Elhennawy K, Schwendicke F. Managing molar-incisor hypomineralization: A systematic review. J Dent. 2016 Dec;55:16-24.	11.07.2019
28	Gao SS, Zhang S, Mei ML, Lo EC, Chu CH. Caries remineralisation and arresting effect in children by professionally applied fluoride treatment – a systematic review. BMC Oral Health. 2016 Feb 1;16:12.	08.07.2019
29	Lenzi TL, Montagner AF, Soares FZ, de Oliveira Rocha R. Are topical fluorides effective for treating incipient carious lesions?: A systematic review and meta-analysis. J Am Dent Assoc. 2016 Feb;147(2):84-91.	11.07.2019
30	Urquhart O, Tampi MP, Pilcher L, Slayton RL, Araujo MWB, Fontana M, Guzmán-Armstrong S, Nascimento MM, Nový BB, Tinanoff N, Weyant RJ, Wolff MS, Young DA, Zero DT, Brignardello-Petersen R, Banfield L, Parikh A, Joshi G, Carrasco-Labra A. Nonrestorative Treatments for Caries: Systematic Review and Network Meta-analysis. J Dent Res. 2019 Jan;98(1):14-26.	01.06.2017*
31	Yengopal V, Mickenautsch S. Caries preventive effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP): a meta-analysis. Acta Odontol Scand. 2009;67(6):321-32.	23.06.2019
32	Chen H, Liu X, Dai J, Jiang Z, Guo T, Ding Y. Effect of remineralizing agents on white spot lesions after orthodontic treatment: a systematic review. Am J Orthod Dentofacial Orthop. 2013 Mar;143(3):376-382.	04.11.2011*
33	Lopatiene K, Borisovaite M, Lapenaite E. Prevention and Treatment of White Spot Lesions During and After Treatment with Fixed Orthodontic Appliances: a Systematic Literature Review. J Oral Maxillofac Res. 2016 Jun 30;7(2):e1.	11.07.2019
34	Wang Y, Li J, Sun W, Li H, Cannon RD, Mei L. Effect of non-fluoride agents on the prevention of dental caries in primary dentition: A systematic review. PloS One. 2017 Aug 7;12(8):e0182221.	16.12.2016*
35	Tao S, Zhu Y, Yuan H, Tao S, Cheng Y, Li J, He L. Efficacy of fluorides and CPP-ACP vs fluorides monotherapy on early caries lesions: A systematic review and meta-analysis. PLoS One. 2018 Apr 30;13(4):e0196660.	01.08.2017*

* Systematic review not updated to date.

Fissure sealant materials

PubMed was searched on the 26 July 2019 for systematic review reports using the search term: ‘fissure sealant’. A total of 58 citations were found. Of these, 15 systematic reviews of clinical trials were included (Table 3). Two of the systematic reviews were further updated in 2019. From the reference check of the systematic reviews a total of 205 trial reports were included for review. Of these, 143 trial reports were found in line with the selection criteria and accepted for data extraction (Figure 3). A total of 267 data points were extracted from the accepted trial reports concerning 77 fissure sealant materials.

Table 3. Fissure sealant materials: Included published systematic reviews

Systematic review reports	Date of most recent update
1	Alirezaei M, Bagherian A, Sarraf Shirazi A. Glass ionomer cements as fissure sealing materials: yes or no?: A systematic review and meta-analysis. J Am Dent Assoc. 2018 Jul;149(7):640-649.e9.	20.09.2017*
2	Papageorgiou SN, Dimitraki D, Kotsanos N, Bekes K, van Waes H. Performance of pit and fissure sealants according to tooth characteristics: A systematic review and meta-analysis. J Dent. 2017 Nov;66:8-17.	23.02.2017*
3	Ahovuo-Saloranta A, Forss H, Walsh T, Nordblad A, Mäkelä M, Worthington HV. Pit and fissure sealants for preventing dental decay in permanent teeth. Cochrane Database Syst Rev. 2017 Jul 31;7:CD001830.	03.08.2016*
4	Wright JT, Tampi MP, Graham L, Estrich C, Crall JJ, Fontana M, Gillette EJ, Nový BB, Dhar V, Donly K, Hewlett ER, Quinonez RB, Chaffin J, Crespin M, Iafolla  T, Siegal MD, Carrasco-Labra A. Sealants for preventing and arresting pit-and-fissure occlusal caries in primary and permanent molars: A systematic review of randomized controlled trials-a report of the American Dental Association and the American Academy of Pediatric Dentistry. J Am Dent Assoc. 2016 Aug;147(8):631-645.e18.	01.05.2013*
5	Mickenautsch S, Yengopal V. Caries-Preventive Effect of High-Viscosity Glass Ionomer and Resin-Based Fissure Sealants on Permanent Teeth: A Systematic Review of Clinical Trials. PLoS One. 2016 Jan 22;11(1):e0146512.	16.01.2015*
6	Hiiri A, Ahovuo-Saloranta A, Nordblad A, Mäkelä M. Pit and fissure sealants versus fluoride varnishes for preventing dental decay in children and adolescents. Cochrane Database Syst Rev. 2010 Mar 17;(3):CD003067.	01.11.2009*
7	Mickenautsch S, Yengopal V. Validity of sealant retention as surrogate for caries prevention–a systematic review. PLoS One. 2013 Oct 23;8(10):e77103.	21.10.2012*
8	Mickenautsch S, Yengopal V. The modified Ottawa method to establish the update need of a systematic review: glass-ionomer versus resin sealants for caries prevention. J Appl Oral Sci. 2013 Sep-Oct;21(5):482-9.	01.05.2012*
9	Kühnisch J, Mansmann U, Heinrich-Weltzien R, Hickel R. Longevity of materials for pit and fissure sealing–results from a meta-analysis. Dent Mater. 2012 Mar;28(3):298-303.	30.09.2011*
10	Yengopal V, Mickenautsch S. Resin-modified glass-ionomer cements versus resin-based materials as fissure sealants: a meta-analysis of clinical trials. Eur Arch Paediatr Dent. 2010 Feb;11(1):18-25.	15.04.2009*
11	Yengopal V, Mickenautsch S, Bezerra AC, Leal SC. Caries-preventive effect of  glass ionomer and resin-based fissure sealants on permanent teeth: a meta analysis. J Oral Sci. 2009 Sep;51(3):373-82.	15.01.2008*
12	Azarpazhooh A, Main PA. Pit and fissure sealants in the prevention of dental caries in children and adolescents: a systematic review. J Can Dent Assoc. 2008 Mar;74(2):171-7.	01.01.2007*
13	16: Beiruti N, Frencken JE, van ‘t Hof MA, van Palenstein Helderman WH. Caries-preventive effect of resin-based and glass ionomer sealants over time: a systematic review. Community Dent Oral Epidemiol. 2006 Dec;34(6):403-9.	01.12.2004*
14	18: Muller-Bolla M, Lupi-Pégurier L, Tardieu C, Velly AM, Antomarchi C. Retention of resin-based pit and fissure sealants: A systematic review. Community Dent Oral Epidemiol. 2006 Oct;34(5):321-36.	09.09.2019
15	20: Mejàre I, Lingström P, Petersson LG, Holm AK, Twetman S, Källestål C, Nordenram G, Lagerlöf F, Söder B, Norlund A, Axelsson S, Dahlgren H. Caries-preventive effect of fissure sealants: a systematic review. Acta Odontol Scand. 2003 Dec;61(6):321-30.	19.08.2019

* Systematic review not updated to date.

Dental filling materials

The databases PubMed, DOAJ, LILACS, IndMed, GoogleScholar were searched up to 26 April 2018 using several strings of search terms (Table 4). In addition, journal hand search was conducted. CNKI database was searched up to 25 July 2018. These two searches were updated on the 27 June 2019 and 14 July 2019, respectively. A total of 739 trial reports were found in line with the selection criteria and accepted for data extraction (Figure 3). A total of 1193 data points were extracted from the accepted trial reports concerning 302 dental filling materials.

Table 4. Dental filling materials: Strings of search terms

Database searched: PubMed / Online: http://www.ncbi.nlm.nih.gov/pubmed

Search terms:[1] (((tooth restoration) OR tooth filling) OR dental filling) OR “Dental Restoration, Permanent”[Mesh] Sort by: PublicationDate Filters: Clinical Trial; Abstract; Humans[2] (amalgam OR composite OR glass-ionomer OR compomer) AND restoration Sort by: PublicationDate Filters: Clinical Trial; Abstract; Humans[3] atraumatic restorative treatment (no filters)[4] composite restorations (Filters activated: Clinical Trial, Abstract.)[5] compomer restoration (Filters activated: Clinical Trial, Abstract.)[6] amalgam restoration (Filters activated: Clinical Trial, Abstract.)[7] glass ionomer restoration (Filters activated: Clinical Trial, Abstract.)

Database searched: DOAJ / Online: http://www.doaj.org

[1] Dental Restoration [2] composite restoration [3] compomer restoration [4] amalgam restoration [5] glass ionomer restoration [6] atraumatic restorative treatment

Database searched: LILACS / Online: http://pesquisa.bvsalud.org/portal/

[1] Dental Restoration [2] composite restoration [3] compomer restoration [4] amalgam restoration [5] glass ionomer restoration [6] atraumatic restorative treatment

Database searched: IndMed / Online: http://indmed.nic.in/indmed.htmlLimit: Controlled Clinical Trial

[1] Dental AND Restoration [2] composite AND restoration [3] compomer AND restoration [4] amalgam AND restoration [5] glass ionomer AND restoration [6] atraumatic AND restorative AND treatment

Database searched: GoogleScholar/ Online: http://indmed.nic.in/indmed.html

[1] “tooth Restoration”+”clinical trial” [2] “composite restoration”+”clinical trial” [3] “compomer restoration”+”clinical trial” [4] “atraumatic restorative treatment”+”clinical trial” [5] “glass ionomer restoration”+”clinical trial” [6] “amalgam restoration”+”clinical trial”

Database searched CNKI / Online: http://cnki.net   Limit: Clinical study

[1] tooth Restoration[2] composite restoration [3] compomer restoration [4] atraumatic restorative treatment [5] glass ionomer restoration [6] amalgam restoration [7] 玻璃离子水门汀                    [8] 光固化复合树脂 AND 修复牙                                 [9] 银汞合金 AND 修复牙

DISCUSSION

Limitations of the applied systematic search strategy

The aim of the applied systematic literature search was to identify as many prospective, clinical controlled trials for caries preventive products/ remineralization products, dental filling materials and fissure sealant materials, as possible. The most important limitations of the search results were the inability to trace 124 trial reports in full copy to date with potential relevance for caries preventive products/ remineralization products and the fact that, so far, 20 out of 35 and 2 out of 15 systematic reviews were updated, only, for caries preventive products/ remineralization products and fissure sealant materials, respectively. However, the RhinshoTrial app, like any systematic review of clinical trials, relies on consistent, regular updating, in order to remain relevant. Hence, continued updates are ongoing, including the tracing of remaining trial reports, which will be added in time to the app’s database. App users can inform themselves about these updates via the app’s online blog.⁹

App strengths 

While many systematic reviews provide their information per product types (Table 2 and 3), such as ‘fluoride varnishes’ or ‘fissure sealants’, the RinshoTrial app provides a unique reference source directly related to specific commercial dental products, based on systematic literature searches exclusively concerning prospective, controlled clinical trials.  Reason for the commercial product focus was the considerations that in the ‘real world’ oral health care providers apply specific products during patient treatment and trialists include specific products into their clinical trials and not random samples of a particular product type. This is important, since many products of the same product type may differ substantially from each other in their (often undisclosed by manufactures) chemical composition and clinical merits.                      

The RinshoTrial app generates easy usable, product specific, reference lists that can be directly emailed from the app to e.g. a collaborating librarian for article tracing. It also provides a geographic overview in form of maps, concerning the location of research centers in the world that included any particular products in their clinical trials (Figure 1). In addition, both reference lists and maps can be easily shared from the app on social media for peer-to-peer or group discussions about a specific product’s clinical evidence-base.

The app provides further opportunities for dental academics, interested in conducting a systematic review to a particular product or product range, in form of a first bibliographic basis as evidence overview. Oral health care provider, who are interested in existing products on the market, have the opportunity to easily access reference lists of clinical trial reports, relevant for reading up on clinical product efficacy. Furthermore, the app provides interested users the opportunity to compare the volume of current clinical evidence between different, perhaps even competing, products.

App limitations

Besides its strengths, RinshoTrial’s most important limitation is its lack of trial quality measure, i.e. the lack of indication regarding trial validity and precision. In this context, app users need to be aware that a large volume of listed trials for a particular product may lead to the false impression that such product has a strong evidence-base or perhaps at least stronger than a product with a fewer amount of listed trials. It is important to note that prospective, controlled clinical trials, albeit being of higher quality than retrospective, uncontrolled or laboratory studies, may still suffer from severe shortcomings, such as a too low sample size or lack of effective randomization. Therefore, further appraisal of trial quality remains warranted before any quality judgment about the evidence-base of a specific product can be made.

Another important limitation of the RinshoTrial app is the ambiguity of non-included products, since such products may either not been included, due to lack of prospective, controlled clinical trials for them or due to any existing trials not been captured into the app’s database, yet. Hence, the app gives no indication for the evidence-base of not included products.

A further limitation is that the app includes only a few dental product categories, so far. However, the utility of the app will increase with its extension to further relevant clinical topics, such as implantology, endodontics or orthodontics. App users are able to receive notification about the inclusion of further added product categories, via the app’s dedicated online notifier.⁹

SUMMARY

Prospective, controlled clinical trials avoid the pitfalls of uncontrolled and/or retrospective clinical study designs. Hence, the identification of such trials provides an important first step when questioning the evidence-base of any dental product. Dissemination of such information to dental academia or oral health care providers with interest in questioning current products on the market, may be assisted through the RinshoTrial app. The app generates easy usable, product specific, reference lists that can be directly emailed from the app and geographic overviews in form of maps, concerning the location of research centers in the world that included any particular product in their clinical trials. In addition, the reference list and maps can be easily shared from the app on social media for peer-to-peer or group discussions. The app’s main limitation is that it gives no indication for the quality of the included trials and thus can only be a supportive tool prior actual trial appraisal.

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