SILVER DIAMINE FLUORIDE: A REVIEW

ABSTRACT


INTRODUCTION
Silver diamine fluoride (SDF) is a colourless alkaline solution that contain ammonia, silver, and fluorine with a pH value between 9 and 10.1 It is a topical solution with increasing application and acceptance in some countries as the silver ion can inhibit bacterial growth and dentine collagen degradation. 1 The fluoride ion has antimicrobial effects on cariogenic bacteria and can help in remineralisation of dental hard tissues by the formation of fluorapatite on the tooth surface. 2 Silver diamine fluoride (SDF) 38% solution formulation contains 44,800 ppm fluoride 2 ions, ,25% silver ions and 5% fluoride ions dissolved in an 8% ammonia solution, there could be variations according to the manufacturer. Ammonia acts as the solution's concentration stabilizer as the solution is unstable and sensitive to light. The various application1 of silver diamine fluoride include to arrest carious lesions in primary teeth and young permanent teeth , to prevent pit and fissure caries in young permanent teeth , to manage dentinal hypersensitivity1 , to prevent secondary caries, for treatment of inaccessible carious lesion, for treatment of unco-operative children with multiple active carious lesion, for silver modified atraumatic restorative treatment technique , for treatment of carious lesion in children with special health care needs and many others in the literature. Silver diamine fluoride therapy or treatment is simple, nonaerosol-generating, painless, non-invasive, requires simple armamentarium and can be done in resource poor settings with minimal support. It causes dark staining3-4 of the carious tooth tissues, as a result of precipitation of silver phosphate.5 Gingival irritation, mucosal irritations and metallic taste are possible disadvantages of the solution. Considering the various applications, advantages and disadvantages of silver diamine fluoride in the literature; and the diverse ethnic groups with various culture, sociocultural beliefs and practices in African region. The aim of this article is to review the available studies on silver diamine fluoride in Africa.

LITERATURE SEARCH METHOD
An electronic literature search in Web of science, Scopus, PubMed, Google Scholar, African journal online, Researchgate and Google was done in May, 2023. The keywords used were silver diamine fluoride , silver fluoride diamine, diamine silver fluoride, Africa countries, African region, Africa continent, .African population, African people, African children, African adolescents and Africa. Search terms and keywords were combined by Boolean operators. Two independent investigators (research assistants) screened titles and abstracts of publications on silver diamine fluoride studies, and potential references to identify which studies met the inclusion criteria of this literature review. Information was extracted from the abstracts and full texts of articles regarding the location of the research and the main content. The inclusion criteria were original research articles, case report, case series related to silver diamine fluoride ( human studies) conducted in African region and in electronic databases, while review articles, systematic reviews, viewpoints, books, letters, editorials, book chapters, perspectives, and news related to silver diamine fluoride were excluded. Study data of the included articles were extracted and collated in a table, including study details (author(s), year of publication, study location or country, study design) .All identified studies in Africa were included and if relevant data were missing, the authors of the articles were contacted for additional information via e-mail. No specified time frame was used during the search, any additional studies in African region identified from the reference lists of published papers were retrieved from the web using Google scholar and Google search engines.

RESULTS
19 articles were identified, eight duplicate were removed during screening. Abstract and full text were screened using inclusion criteria by two independent research assistants . One article was excluded because it was a systematic review. Ten articles were included as they were assessed to meet the aim of the review.
The ten articles included were four invitro studies, three randomized controlled clinical trial, one randomized clinical trial, one split-mouth, self-controlled clinical trial and one split-mouth, randomized controlled clinical study. Nine of the studies were conducted in Egypt, North Africa, while one was conducted in Nigeria, West Africa.

DISCUSSION
The level of untreated dental caries among African children12 and adolescents are high. Silver diamine fluoride can be used as an intervention to stop the progression13 of active carious lesion and restore untreated carious teeth using the silver modified atraumatic restorative treatment technique. Silver diamine fluoride (SDF), also known as silver fluoride diamine or diamine silver fluoride is not available in most Africa countries,1 and oral health practitioners, parents, caregivers, guardians and children may have concerns of the dark staining of teeth after it use. A formulation of 38% SDF with potassium iodide (KI), 4 applied as a separate reagent, have been suggested by some researchers to reduce the staining effect of silver phosphate, by generating silver iodide, but silver iodide is photosensitive and can darken when exposed to light.
The armamentarium for silver diamine fluoride application10 is simple, the therapy is non-technique sensitive and it could be used in underserved and un-served children with active carious lesions. 13 This review identified studies on silver diamine fluoride from two countries in African region and 90 % of the studies was from one country. One of the studies identified was a school based study, while four of the studies were hospital based studies. None of the studies identified were community based or rural community based studies. More studies from other countries in the region will guide recommendations on evidence based practice for silver diamine fluoride among African children.

CONCLUSION
Studies on silver diamine fluoride (SDF) in African countries are few and limited to few countries. Silver diamine fluoride can be used as an intervention for active and progressing untreated carious lesion in primary teeth among underserved or un-served children. More studies from the diverse ethnic population in Africa will contribute to the existing literature.

CONFLICTS OF INTEREST
There are no conflicts of interest