diff --git a/pom.xml b/pom.xml
index ff30608..f0530a2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -80,11 +80,6 @@
             <artifactId>metafy</artifactId>
             <version>0.1.2</version>
         </dependency>
-        <dependency>
-            <groupId>org.apache.commons</groupId>
-            <artifactId>commons-text</artifactId>
-            <version>1.9</version>
-        </dependency>
     </dependencies>
 
 
diff --git a/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthRule.kt b/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthRule.kt
index bf0d644..f36f61a 100644
--- a/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthRule.kt
+++ b/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthRule.kt
@@ -1,14 +1,14 @@
 package br.ufsc.bridge.platform.validation.rules
 
 import br.ufsc.bridge.platform.validation.engine.Rule
+import br.ufsc.bridge.platform.validation.util.HtmlUtil
 import br.ufsc.bridge.platform.validation.util.RegexUtil
 import br.ufsc.bridge.platform.validation.util.Util
-import org.apache.commons.text.StringEscapeUtils
 
 class RichTextMaxLengthRule(private val maxLength: Int) : Rule<String?> {
 
     override fun validate(value: String?): String? {
-        val text = StringEscapeUtils.unescapeHtml4(value?.replace(RegexUtil.HTML_TAG_PATTERN, ""))
-        return if (!Util.isEmpty(text) && text.length > maxLength) "Deve possuir no máximo $maxLength caractere(s)" else null
+        val text = HtmlUtil.unescapeHtml(value?.replace(RegexUtil.HTML_TAG_PATTERN, ""))
+        return if (!Util.isEmpty(text) && text!!.length > maxLength) "Deve possuir no máximo $maxLength caractere(s)" else null
     }
 }
diff --git a/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthRule.kt b/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthRule.kt
index 2e5c1ab..bd64645 100644
--- a/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthRule.kt
+++ b/src/main/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthRule.kt
@@ -1,15 +1,15 @@
 package br.ufsc.bridge.platform.validation.rules
 
 import br.ufsc.bridge.platform.validation.engine.Rule
+import br.ufsc.bridge.platform.validation.util.HtmlUtil
 import br.ufsc.bridge.platform.validation.util.RegexUtil
 import br.ufsc.bridge.platform.validation.util.Util
-import org.apache.commons.text.StringEscapeUtils
 
 class RichTextMinLengthRule(private val minLength: Int) : Rule<String?> {
 
     override fun validate(value: String?): String? {
-        val text = StringEscapeUtils.unescapeHtml4(value?.replace(RegexUtil.HTML_TAG_PATTERN, ""))
-        return if (Util.isEmpty(text) || text.length < minLength) {
+        val text = HtmlUtil.unescapeHtml(value?.replace(RegexUtil.HTML_TAG_PATTERN, ""))
+        return if (Util.isEmpty(text) || text!!.length < minLength) {
             "Deve possuir ao menos $minLength caractere(s)"
         } else null
     }
diff --git a/src/main/kotlin/br/ufsc/bridge/platform/validation/util/HtmlUtil.kt b/src/main/kotlin/br/ufsc/bridge/platform/validation/util/HtmlUtil.kt
new file mode 100644
index 0000000..c4236e0
--- /dev/null
+++ b/src/main/kotlin/br/ufsc/bridge/platform/validation/util/HtmlUtil.kt
@@ -0,0 +1,105 @@
+package br.ufsc.bridge.platform.validation.util
+
+object HtmlUtil {
+
+    fun unescapeHtml(value: String?): String? {
+        if (value == null || value.indexOf('&') < 0) return value
+        val result = StringBuilder(value.length)
+        var index = 0
+        while (index < value.length) {
+            val char = value[index]
+            if (char != '&') {
+                result.append(char)
+                index++
+                continue
+            }
+            val semicolonIndex = value.indexOf(';', index + 1)
+            if (semicolonIndex < 0) {
+                result.append(value, index, value.length)
+                break
+            }
+            val unescaped = unescapeEntity(value.substring(index + 1, semicolonIndex))
+            if (unescaped != null) {
+                result.append(unescaped)
+                index = semicolonIndex + 1
+            } else {
+                result.append('&')
+                index++
+            }
+        }
+        return result.toString()
+    }
+
+    private fun unescapeEntity(entity: String): String? {
+        if (entity.isEmpty()) return null
+        if (entity[0] != '#') return NAMED_ENTITIES[entity]?.toString()
+        val isHex = entity.length > 1 && (entity[1] == 'x' || entity[1] == 'X')
+        val codePoint = if (isHex) entity.substring(2).toIntOrNull(16) else entity.substring(1).toIntOrNull()
+        return if (codePoint != null && codePoint in 0..0x10FFFF) String(Character.toChars(codePoint)) else null
+    }
+
+    // Entidades definidas pelo HTML 4.0 ("apos" nao faz parte do HTML 4 e por isso nao eh tratada)
+    private val NAMED_ENTITIES: Map<String, Char> = HashMap<String, Char>().apply {
+        put("quot", '"')
+        put("amp", '&')
+        put("lt", '<')
+        put("gt", '>')
+
+        // Entidades ISO-8859-1, com codigos sequenciais a partir de 160
+        listOf(
+            "nbsp", "iexcl", "cent", "pound", "curren", "yen", "brvbar", "sect",
+            "uml", "copy", "ordf", "laquo", "not", "shy", "reg", "macr",
+            "deg", "plusmn", "sup2", "sup3", "acute", "micro", "para", "middot",
+            "cedil", "sup1", "ordm", "raquo", "frac14", "frac12", "frac34", "iquest",
+            "Agrave", "Aacute", "Acirc", "Atilde", "Auml", "Aring", "AElig", "Ccedil",
+            "Egrave", "Eacute", "Ecirc", "Euml", "Igrave", "Iacute", "Icirc", "Iuml",
+            "ETH", "Ntilde", "Ograve", "Oacute", "Ocirc", "Otilde", "Ouml", "times",
+            "Oslash", "Ugrave", "Uacute", "Ucirc", "Uuml", "Yacute", "THORN", "szlig",
+            "agrave", "aacute", "acirc", "atilde", "auml", "aring", "aelig", "ccedil",
+            "egrave", "eacute", "ecirc", "euml", "igrave", "iacute", "icirc", "iuml",
+            "eth", "ntilde", "ograve", "oacute", "ocirc", "otilde", "ouml", "divide",
+            "oslash", "ugrave", "uacute", "ucirc", "uuml", "yacute", "thorn", "yuml"
+        ).forEachIndexed { offset, name -> put(name, (160 + offset).toChar()) }
+
+        // Entidades de simbolos, letras gregas e pontuacao
+        listOf(
+            "fnof" to 402,
+            "Alpha" to 913, "Beta" to 914, "Gamma" to 915, "Delta" to 916, "Epsilon" to 917,
+            "Zeta" to 918, "Eta" to 919, "Theta" to 920, "Iota" to 921, "Kappa" to 922,
+            "Lambda" to 923, "Mu" to 924, "Nu" to 925, "Xi" to 926, "Omicron" to 927,
+            "Pi" to 928, "Rho" to 929, "Sigma" to 931, "Tau" to 932, "Upsilon" to 933,
+            "Phi" to 934, "Chi" to 935, "Psi" to 936, "Omega" to 937,
+            "alpha" to 945, "beta" to 946, "gamma" to 947, "delta" to 948, "epsilon" to 949,
+            "zeta" to 950, "eta" to 951, "theta" to 952, "iota" to 953, "kappa" to 954,
+            "lambda" to 955, "mu" to 956, "nu" to 957, "xi" to 958, "omicron" to 959,
+            "pi" to 960, "rho" to 961, "sigmaf" to 962, "sigma" to 963, "tau" to 964,
+            "upsilon" to 965, "phi" to 966, "chi" to 967, "psi" to 968, "omega" to 969,
+            "thetasym" to 977, "upsih" to 978, "piv" to 982,
+            "bull" to 8226, "hellip" to 8230, "prime" to 8242, "Prime" to 8243, "oline" to 8254,
+            "frasl" to 8260, "weierp" to 8472, "image" to 8465, "real" to 8476, "trade" to 8482,
+            "alefsym" to 8501,
+            "larr" to 8592, "uarr" to 8593, "rarr" to 8594, "darr" to 8595, "harr" to 8596,
+            "crarr" to 8629, "lArr" to 8656, "uArr" to 8657, "rArr" to 8658, "dArr" to 8659,
+            "hArr" to 8660,
+            "forall" to 8704, "part" to 8706, "exist" to 8707, "empty" to 8709, "nabla" to 8711,
+            "isin" to 8712, "notin" to 8713, "ni" to 8715, "prod" to 8719, "sum" to 8721,
+            "minus" to 8722, "lowast" to 8727, "radic" to 8730, "prop" to 8733, "infin" to 8734,
+            "ang" to 8736, "and" to 8743, "or" to 8744, "cap" to 8745, "cup" to 8746,
+            "int" to 8747, "there4" to 8756, "sim" to 8764, "cong" to 8773, "asymp" to 8776,
+            "ne" to 8800, "equiv" to 8801, "le" to 8804, "ge" to 8805, "sub" to 8834,
+            "sup" to 8835, "nsub" to 8836, "sube" to 8838, "supe" to 8839, "oplus" to 8853,
+            "otimes" to 8855, "perp" to 8869, "sdot" to 8901,
+            "lceil" to 8968, "rceil" to 8969, "lfloor" to 8970, "rfloor" to 8971,
+            "lang" to 9001, "rang" to 9002, "loz" to 9674,
+            "spades" to 9824, "clubs" to 9827, "hearts" to 9829, "diams" to 9830,
+            "OElig" to 338, "oelig" to 339, "Scaron" to 352, "scaron" to 353, "Yuml" to 376,
+            "circ" to 710, "tilde" to 732,
+            "ensp" to 8194, "emsp" to 8195, "thinsp" to 8201, "zwnj" to 8204, "zwj" to 8205,
+            "lrm" to 8206, "rlm" to 8207, "ndash" to 8211, "mdash" to 8212,
+            "lsquo" to 8216, "rsquo" to 8217, "sbquo" to 8218,
+            "ldquo" to 8220, "rdquo" to 8221, "bdquo" to 8222,
+            "dagger" to 8224, "Dagger" to 8225, "permil" to 8240,
+            "lsaquo" to 8249, "rsaquo" to 8250, "euro" to 8364
+        ).forEach { (name, code) -> put(name, code.toChar()) }
+    }
+}
diff --git a/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthTest.kt b/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthTest.kt
index d717115..faad2b8 100644
--- a/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthTest.kt
+++ b/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMaxLengthTest.kt
@@ -21,4 +21,40 @@ class RichTextMaxLengthTest : ValidationTest() {
     fun `Atributo com length menor que o max eh valido`(){
         assertNull(validate("Lorem <em>dolor</em> sit <strong>ipsum</strong>.", richTextMaxLength(25)))
     }
+
+    @Test
+    fun `Atributo com length igual ao max eh valido`() {
+        assertNull(validate("<p>12345</p>", richTextMaxLength(5)))
+    }
+
+    @Test
+    fun `Atributo apenas com tags eh valido`() {
+        assertNull(validate("<p><br></p>", richTextMaxLength(0)))
+    }
+
+    @Test
+    fun `Entidade conta como um unico caractere`() {
+        // "&lt;ab&gt;" representa "<ab>", 4 caracteres
+        assertNull(validate("<p>&lt;ab&gt;</p>", richTextMaxLength(4)))
+        assertNotNull(validate("<p>&lt;ab&gt;</p>", richTextMaxLength(3)))
+    }
+
+    @Test
+    fun `Entidade numerica conta como um unico caractere`() {
+        // "d&#39;agua" representa "d'agua", 6 caracteres
+        assertNull(validate("<p>d&#39;agua</p>", richTextMaxLength(6)))
+        assertNotNull(validate("<p>d&#39;agua</p>", richTextMaxLength(5)))
+    }
+
+    @Test
+    fun `Texto com acentos escapados eh medido pelo texto convertido`() {
+        // "valida&ccedil;&atilde;o" representa "validação", 9 caracteres
+        assertNull(validate("valida&ccedil;&atilde;o", richTextMaxLength(9)))
+        assertNotNull(validate("valida&ccedil;&atilde;o", richTextMaxLength(8)))
+    }
+
+    @Test
+    fun `Quebras de linha sao removidas da contagem`() {
+        assertNull(validate("<p>abc</p>\n<p>def</p>", richTextMaxLength(6)))
+    }
 }
diff --git a/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthTest.kt b/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthTest.kt
index b233f84..3b33e7c 100644
--- a/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthTest.kt
+++ b/src/test/kotlin/br/ufsc/bridge/platform/validation/rules/RichTextMinLengthTest.kt
@@ -30,4 +30,40 @@ class RichTextMinLengthTest : ValidationTest() {
     fun `Atributo com length maior que o min eh valido`(){
         assertNull(validate("Lorem <em>dolor</em> sit <strong>ipsum</strong>.", Rules.richTextMinLength(10)))
     }
+
+    @Test
+    fun `Atributo com length igual ao min eh valido`() {
+        assertNull(validate("<p>12345</p>", Rules.richTextMinLength(5)))
+    }
+
+    @Test
+    fun `Atributo vazio eh invalido`() {
+        assertNotNull(validate("", Rules.richTextMinLength(1)))
+    }
+
+    @Test
+    fun `Entidade conta como um unico caractere`() {
+        // "&lt;ab&gt;" representa "<ab>", 4 caracteres
+        assertNull(validate("<p>&lt;ab&gt;</p>", Rules.richTextMinLength(4)))
+        assertNotNull(validate("<p>&lt;ab&gt;</p>", Rules.richTextMinLength(5)))
+    }
+
+    @Test
+    fun `Entidade numerica conta como um unico caractere`() {
+        // "d&#39;agua" representa "d'agua", 6 caracteres
+        assertNull(validate("<p>d&#39;agua</p>", Rules.richTextMinLength(6)))
+        assertNotNull(validate("<p>d&#39;agua</p>", Rules.richTextMinLength(7)))
+    }
+
+    @Test
+    fun `Texto com acentos escapados eh medido pelo texto convertido`() {
+        // "valida&ccedil;&atilde;o" representa "validação", 9 caracteres
+        assertNull(validate("valida&ccedil;&atilde;o", Rules.richTextMinLength(9)))
+        assertNotNull(validate("valida&ccedil;&atilde;o", Rules.richTextMinLength(10)))
+    }
+
+    @Test
+    fun `Quebras de linha nao contam para o tamanho minimo`() {
+        assertNotNull(validate("<p>ab</p>\n<p>cd</p>", Rules.richTextMinLength(5)))
+    }
 }
\ No newline at end of file
diff --git a/src/test/kotlin/br/ufsc/bridge/platform/validation/util/HtmlUtilTest.kt b/src/test/kotlin/br/ufsc/bridge/platform/validation/util/HtmlUtilTest.kt
new file mode 100644
index 0000000..9d88931
--- /dev/null
+++ b/src/test/kotlin/br/ufsc/bridge/platform/validation/util/HtmlUtilTest.kt
@@ -0,0 +1,115 @@
+package br.ufsc.bridge.platform.validation.util
+
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertNull
+
+class HtmlUtilTest {
+
+    @Test
+    fun `Null retorna null`() {
+        assertNull(HtmlUtil.unescapeHtml(null))
+    }
+
+    @Test
+    fun `String vazia retorna vazia`() {
+        assertEquals("", HtmlUtil.unescapeHtml(""))
+    }
+
+    @Test
+    fun `String sem entidades eh mantida`() {
+        assertEquals("Lorem ipsum dolor", HtmlUtil.unescapeHtml("Lorem ipsum dolor"))
+    }
+
+    @Test
+    fun `Entidades basicas sao convertidas`() {
+        assertEquals("<teste>", HtmlUtil.unescapeHtml("&lt;teste&gt;"))
+        assertEquals("a & b", HtmlUtil.unescapeHtml("a &amp; b"))
+        assertEquals("\"aspas\"", HtmlUtil.unescapeHtml("&quot;aspas&quot;"))
+    }
+
+    @Test
+    fun `Entidades ISO-8859-1 sao convertidas`() {
+        assertEquals(" ", HtmlUtil.unescapeHtml("&nbsp;"))
+        assertEquals("ação", HtmlUtil.unescapeHtml("a&ccedil;&atilde;o"))
+        assertEquals("é É à Ü ñ ÿ", HtmlUtil.unescapeHtml("&eacute; &Eacute; &agrave; &Uuml; &ntilde; &yuml;"))
+        assertEquals("© ® ° ÷ ×", HtmlUtil.unescapeHtml("&copy; &reg; &deg; &divide; &times;"))
+    }
+
+    @Test
+    fun `Entidades de simbolos e letras gregas sao convertidas`() {
+        assertEquals("α β Ω π", HtmlUtil.unescapeHtml("&alpha; &beta; &Omega; &pi;"))
+        assertEquals("• … ™ €", HtmlUtil.unescapeHtml("&bull; &hellip; &trade; &euro;"))
+        assertEquals("← → ∑ ≠ ≤", HtmlUtil.unescapeHtml("&larr; &rarr; &sum; &ne; &le;"))
+        assertEquals("‘aspas’ “duplas” – —", HtmlUtil.unescapeHtml("&lsquo;aspas&rsquo; &ldquo;duplas&rdquo; &ndash; &mdash;"))
+    }
+
+    @Test
+    fun `Entidades numericas decimais sao convertidas`() {
+        assertEquals("A", HtmlUtil.unescapeHtml("&#65;"))
+        assertEquals("d'agua", HtmlUtil.unescapeHtml("d&#39;agua"))
+        assertEquals("ç", HtmlUtil.unescapeHtml("&#231;"))
+    }
+
+    @Test
+    fun `Entidades numericas hexadecimais sao convertidas`() {
+        assertEquals("A", HtmlUtil.unescapeHtml("&#x41;"))
+        assertEquals("A", HtmlUtil.unescapeHtml("&#X41;"))
+        assertEquals("'", HtmlUtil.unescapeHtml("&#x27;"))
+    }
+
+    @Test
+    fun `Entidade numerica fora do BMP gera par substituto`() {
+        assertEquals("💩", HtmlUtil.unescapeHtml("&#128169;"))
+        assertEquals("💩", HtmlUtil.unescapeHtml("&#x1F4A9;"))
+    }
+
+    @Test
+    fun `Entidade desconhecida eh mantida`() {
+        assertEquals("&desconhecida;", HtmlUtil.unescapeHtml("&desconhecida;"))
+        assertEquals("&apos;", HtmlUtil.unescapeHtml("&apos;"))
+    }
+
+    @Test
+    fun `Entidade sem ponto e virgula eh mantida`() {
+        assertEquals("&amp", HtmlUtil.unescapeHtml("&amp"))
+        assertEquals("&#65", HtmlUtil.unescapeHtml("&#65"))
+        assertEquals("a & b", HtmlUtil.unescapeHtml("a & b"))
+    }
+
+    @Test
+    fun `Entidade malformada eh mantida`() {
+        assertEquals("&;", HtmlUtil.unescapeHtml("&;"))
+        assertEquals("&#;", HtmlUtil.unescapeHtml("&#;"))
+        assertEquals("&#x;", HtmlUtil.unescapeHtml("&#x;"))
+        assertEquals("&#12ab;", HtmlUtil.unescapeHtml("&#12ab;"))
+        assertEquals("&#-12;", HtmlUtil.unescapeHtml("&#-12;"))
+        assertEquals("&#1114112;", HtmlUtil.unescapeHtml("&#1114112;"))
+    }
+
+    @Test
+    fun `Escape duplo eh convertido apenas uma vez`() {
+        assertEquals("&amp;", HtmlUtil.unescapeHtml("&amp;amp;"))
+        assertEquals("&lt;", HtmlUtil.unescapeHtml("&amp;lt;"))
+    }
+
+    @Test
+    fun `Entidades sao sensiveis a maiusculas e minusculas`() {
+        assertEquals("Σ σ", HtmlUtil.unescapeHtml("&Sigma; &sigma;"))
+        assertEquals("&AMP;", HtmlUtil.unescapeHtml("&AMP;"))
+    }
+
+    @Test
+    fun `Texto com varias entidades misturadas eh convertido`() {
+        assertEquals(
+            "São José <1 & >2  fim",
+            HtmlUtil.unescapeHtml("S&atilde;o Jos&eacute; &lt;1 &amp; &gt;2 &nbsp;fim")
+        )
+    }
+
+    @Test
+    fun `E comercial seguido de entidade valida converte apenas a entidade`() {
+        assertEquals("&<", HtmlUtil.unescapeHtml("&&lt;"))
+        assertEquals("&foo<", HtmlUtil.unescapeHtml("&foo&lt;"))
+    }
+}