{
    "title": "Tooth Patch",
    "inventor_name": "Shigeki Hontsu (et al.)",
    "publication_year": 2012,
    "device_name": "Tooth Patch",
    "goal": "Prevent tooth decay, protect enamel, and provide cosmetic whitening by coating teeth with a thin, biocompatible hydroxyapatite film.",
    "problem_addressed": "Dental decay, enamel erosion, and tooth sensitivity.",
    "concept_summary": "A microscopically thin, flexible, and hard-wearing film made from hydroxyapatite (the main mineral of tooth enamel) is produced by laser ablation of compressed hydroxyapatite blocks in a vacuum. The resulting particles are collected on a heated salt substrate, dissolved, and the film is dried and lifted onto a tooth. The film adheres within about a day, is invisible when applied, and can be made white for cosmetic use.",
    "detailed_description": "Researchers fire lasers at compressed hydroxyapatite blocks in a vacuum, causing particles to pop out and fall onto a heated block of salt. The salt is then dissolved in water, leaving the hydroxyapatite particles on a filter paper which is dried. The resulting film is about 0.004 mm thick, flexible, and can be handled with tweezers. It contains minute holes to allow liquid and air to escape, preventing bubble formation. The film becomes invisible on the tooth surface and adheres firmly after roughly one day. The technology is patented in Japan and South Korea and is being explored for dental and cosmetic applications.",
    "category": "Medical & Dental Technologies",
    "principles": [
        "Biocompatibility of hydroxyapatite",
        "Laser ablation deposition",
        "Thin-film barrier protection",
        "Vacuum particle formation",
        "Salt substrate dissolution"
    ],
    "scientific_domains": [
        "Materials Science",
        "Dentistry",
        "Biomaterials"
    ],
    "mechanisms_of_action": [
        "Physical barrier against acid and bacterial attack",
        "Mimicry of natural enamel mineral composition",
        "Potential remineralization of damaged enamel",
        "Cosmetic whitening when made opaque"
    ],
    "materials": [
        "Hydroxyapatite",
        "Sodium chloride (salt substrate)",
        "Water"
    ],
    "energy_sources": [
        "Laser (for ablation)"
    ],
    "inputs": [
        "Compressed hydroxyapatite blocks",
        "Laser energy",
        "Vacuum environment",
        "Salt (NaCl) block",
        "Water for dissolution"
    ],
    "outputs": [
        "Transparent, flexible hydroxyapatite film (tooth patch)"
    ],
    "claimed_performance": "Film thickness 0.004 mm, hard-wearing, ultra-flexible, invisible when applied, adheres within ~24 hours, can be made white for cosmetic use.",
    "experimental_evidence": "Researchers have applied the film to disused human teeth and are planning animal tests; no quantitative performance data are provided.",
    "replication_status": "Patented in Japan and South Korea; applications underway in US, Europe, and China; still in laboratory testing phase.",
    "keywords": [
        "hydroxyapatite",
        "tooth coating",
        "dental sealant",
        "biocompatible film",
        "laser ablation",
        "enamel repair"
    ],
    "related_technologies": [
        "Dental sealants",
        "Enamel remineralization agents",
        "Biocompatible ceramic coatings"
    ],
    "controversy_level": "low",
    "confidence_score": 0.9,
    "practicability_score": 0.6,
    "fringe_score": 0.2,
    "evidence_strength": 0.4,
    "risk_score": 0.2,
    "trl_estimate": 4,
    "source_urls": [
        "http://www.france24.com/en/20120916-japan-tooth-patch-could-be-end-decay",
        "https://patents.google.com/patent/US2009311297"
    ],
    "organizations": [
        "Kinki University",
        "Osaka Dental University"
    ],
    "applications": [
        "Dental decay prevention",
        "Sensitive-tooth protection",
        "Cosmetic tooth whitening",
        "Artificial enamel repair"
    ],
    "limitations": [
        "Adhesion requires ~1 day",
        "Manufacturing relies on laser equipment and vacuum",
        "Long-term durability not yet demonstrated",
        "Scale-up for mass production not proven"
    ],
    "open_questions": [
        "How effective is the film at preventing caries in vivo?",
        "What is the lifespan of the coating under normal oral conditions?",
        "Can the production process be cost-effective for widespread dental use?",
        "Will the film cause any adverse tissue reactions over long periods?"
    ],
    "red_flags": [],
    "evidence_quotes": [
        "Researchers can create film just 0.004 millimetres (0.00016 inches) thick by firing lasers at compressed blocks of hydroxyapatite in a vacuum to make individual particles pop out.",
        "The moment you put it on a tooth surface, it becomes invisible. You can barely see it if you examine it under a light.",
        "One problem is that it takes almost one day for the film to adhere firmly to the tooth's surface.",
        "Researchers are experimenting on disused human teeth at the moment but the team will soon move to tests with animals.",
        "Five years or more would be needed before the film could be used in practical dental treatment such as covering exposed dentin -- the sensitive layer underneath enamel -- but it could be used cosmetically within three years."
    ]
}