WEBVTT 1 00:00:00.160 --> 00:00:03.399 Imagine a patient walks into your clinic complaining that their 2 00:00:03.439 --> 00:00:06.599 favorite hat just doesn't fit anymore, and on top of that, 3 00:00:06.679 --> 00:00:10.160 their dentures are suddenly falling out. A regular mechanic might 4 00:00:10.199 --> 00:00:13.000 look at that and see two completely different parts, you know, 5 00:00:13.599 --> 00:00:15.560 like a head issue and a mouth issue. 6 00:00:15.400 --> 00:00:18.480 Right, But a great diagnostician they know that patient's skull 7 00:00:18.679 --> 00:00:23.039 is actively growing. It's the ultimate clinical puzzle. 8 00:00:22.839 --> 00:00:27.160 Really exactly. You aren't just looking at isolated mechanical failures. 9 00:00:26.839 --> 00:00:30.600 No, not at all. The mouth is essentially the check 10 00:00:30.640 --> 00:00:32.520 engine light for the entire human body. 11 00:00:32.679 --> 00:00:35.039 And that is the exact kind of medical detective work 12 00:00:35.079 --> 00:00:37.880 we are getting into today. Welcome to this deep dive. 13 00:00:38.280 --> 00:00:40.920 We're looking at a massive stack of clinical data today, 14 00:00:41.479 --> 00:00:46.119 specifically the DENTIN NBD Part two board review material. 15 00:00:46.240 --> 00:00:48.600 It's a huge amount of information, it really is. 16 00:00:48.840 --> 00:00:51.320 So whether you are a dental student staring down your 17 00:00:51.320 --> 00:00:54.280 exams or you know a practitioner looking to sharpen your 18 00:00:54.280 --> 00:00:57.280 diagnostic edge, we are going to look way past the 19 00:00:57.359 --> 00:01:00.479 rote memorization. We are going to figure out out how 20 00:01:00.520 --> 00:01:03.759 to read the subtle, often hidden clues the body leaves 21 00:01:03.880 --> 00:01:07.920 right there in the oral cavity. So to solve that 22 00:01:08.040 --> 00:01:10.959 hat puzzle right out of the gate, What is actually 23 00:01:11.000 --> 00:01:12.439 happening to that patient. 24 00:01:12.239 --> 00:01:16.000 Well, you're likely looking at Paget's disease, yeah, or Ossiidi's deformans. 25 00:01:16.040 --> 00:01:20.799 The normal process of bone breaking down and rebuilding goes 26 00:01:20.840 --> 00:01:21.799 completely haywire. 27 00:01:21.879 --> 00:01:23.719 It just loses its structure exactly. 28 00:01:23.799 --> 00:01:26.319 It becomes incredibly unorganized. Like if you run a blood test, 29 00:01:26.319 --> 00:01:30.239 you'll see a massive spike in serum alkaline phosphatase. And 30 00:01:30.239 --> 00:01:34.319 if you take a cranial radiograph, the skull looks bizarrely. 31 00:01:33.840 --> 00:01:37.799 Fluffy, like the classic cotton wool appearance right exactly cotton wool. 32 00:01:37.959 --> 00:01:40.719 The bone is literally expanding, which is exactly why the 33 00:01:40.760 --> 00:01:43.560 hat doesn't fit, and the dentures just lose their seat entirely. 34 00:01:43.959 --> 00:01:47.560 Man, that perfectly illustrates how a systemic issue crashes right 35 00:01:47.599 --> 00:01:48.879 into clinical dentistry. 36 00:01:49.159 --> 00:01:53.159 Let's look deeper into that systemic oral connection, because I mean, 37 00:01:53.640 --> 00:01:55.359 before we even pick up a mirror to look at 38 00:01:55.400 --> 00:01:57.840 a tooth, we really have to respect the endocrine system. 39 00:01:58.040 --> 00:02:01.159 Hormones are basically the master switches for the entire body. 40 00:02:01.480 --> 00:02:05.719 They absolutely are, and the thyroid gland is a prime 41 00:02:05.760 --> 00:02:09.479 example of how extreme those switches can be. Take hyperthyroidism, 42 00:02:09.520 --> 00:02:12.360 where you have this huge excess of the hormone thyroxin. 43 00:02:12.520 --> 00:02:14.879 The patient's metabolism is just redlining at that point. 44 00:02:14.960 --> 00:02:18.120 Oh completely, They're sweating, they're losing weight, their heart rate 45 00:02:18.240 --> 00:02:22.479 is up. You'll often see Graves disease, which presents with 46 00:02:22.599 --> 00:02:25.800 a visibly bulging neck, a goiter, and bulging eyes. 47 00:02:26.039 --> 00:02:30.039 Right, But then there's Plumber's disease, which is similar but different. 48 00:02:30.120 --> 00:02:33.520 Yeah, Plumber's disease features toxic nodules on the thyroid, though 49 00:02:33.599 --> 00:02:36.039 usually you know, without the bulging eyes you see in Graves. 50 00:02:36.120 --> 00:02:39.319 Okay, but flip that switch the other way to hypothyroidism, 51 00:02:39.400 --> 00:02:42.199 and everything just grinds to a halt. The engine is flooded. 52 00:02:42.360 --> 00:02:45.599 You get weight gain, chronic fatigue. Right, And if it's 53 00:02:45.599 --> 00:02:47.800 severe in adults, it's called mixed adema where the skin 54 00:02:47.840 --> 00:02:50.919 gets really puffy and dry, or you know, it could 55 00:02:50.960 --> 00:02:54.280 be hashimotos which is an autoimmune attack on the thyroid itself. 56 00:02:54.319 --> 00:02:57.280 But what I find crucial is how this actually manifests 57 00:02:57.400 --> 00:02:58.759 in a developing child. 58 00:02:58.840 --> 00:03:03.759 Yeah, that's a massive topic. In children, severe hypothyroidism is 59 00:03:03.759 --> 00:03:08.000 called cretanism, and because the thyroid drives metabolic development, a 60 00:03:08.120 --> 00:03:10.840 lack of it just severely stunts physical growth. 61 00:03:10.919 --> 00:03:13.400 So clinically, what are you seeing in the chair? 62 00:03:13.960 --> 00:03:15.759 You're going to see a delayed eruption of the teeth, 63 00:03:16.080 --> 00:03:21.800 a very underdeveloped jaw, and a macroglossic or abnormally large tone. 64 00:03:22.120 --> 00:03:25.479 Wow, so the mouth is directly reflecting a metabolic traffic jam. 65 00:03:25.680 --> 00:03:28.960 We see similar calcium traffic jams with the parathyroid gland. 66 00:03:29.039 --> 00:03:32.840 Definitely, a hyperactive parathyroid gives you kidney stones and these 67 00:03:32.960 --> 00:03:35.360 crazy giant cell granulomas. 68 00:03:34.759 --> 00:03:37.520 In the jaws, and underactive is linked to conditions like 69 00:03:37.560 --> 00:03:41.360 to Georgia syndrome. But I'm stuck on the pituitary gland. 70 00:03:41.599 --> 00:03:44.919 The source material really emphasizes the timing of a pituitary 71 00:03:44.960 --> 00:03:50.319 tumor secreting excess growth hormone. Why is the timing so incredibly. 72 00:03:49.840 --> 00:03:54.360 Critical because it dictates the entire architectural outcome of the body. 73 00:03:54.439 --> 00:03:56.719 It all hinges on whether the growth plates in the 74 00:03:56.759 --> 00:03:59.680 long bones the epiphysis have fused yet. 75 00:04:00.000 --> 00:04:03.319 Okay, so it's like a factory's production line. If the 76 00:04:03.319 --> 00:04:06.759 growth hormone machine gets stuck on high before the structural 77 00:04:06.759 --> 00:04:09.080 scaffolding of the body is finished, you get a giant 78 00:04:09.120 --> 00:04:10.360 building exactly. 79 00:04:10.360 --> 00:04:11.400 That is gigantism. 80 00:04:11.639 --> 00:04:13.879 But if that machine gets stuck on high after the 81 00:04:13.919 --> 00:04:16.399 building is already done, like in a middle aged adult, 82 00:04:17.000 --> 00:04:19.279 the existing walls just bulge out. 83 00:04:19.480 --> 00:04:21.800 That's acromegaly. And you see it right there in the 84 00:04:21.879 --> 00:04:26.639 dental chair. The mandible literally expands, causing an underbite or prognifism. 85 00:04:27.040 --> 00:04:29.959 The teeth spread apart and the tongue enlarges. 86 00:04:29.439 --> 00:04:32.839 Wild And conversely, if there's a severe lack of growth hormone, 87 00:04:32.879 --> 00:04:36.800 you see dwarfism like achondriplasia, which again gives you delayed 88 00:04:36.800 --> 00:04:38.720 tooth eruption and a really crowded dental art. 89 00:04:38.920 --> 00:04:40.000 Right, it's all connected. 90 00:04:40.240 --> 00:04:43.120 Let's talk about the biological materials themselves for a second. 91 00:04:43.439 --> 00:04:47.759 Osteogenesis in perfecta riddle bone disease. I know this is 92 00:04:48.399 --> 00:04:51.279 a genetic collagen defect, and you might notice a blue 93 00:04:51.319 --> 00:04:53.839 tint to the whites of the patient's size, But how 94 00:04:53.839 --> 00:04:56.279 does faulty collagen actually affect the teeth? 95 00:04:56.680 --> 00:04:59.639 Well, because dentin, the layer just beneath the tooth and 96 00:04:59.680 --> 00:05:04.279 anmel is absolutely packed with collagen. So osteogenesis imperfecta is 97 00:05:04.399 --> 00:05:08.439 tightly linked to type one dentiogenesis imperfecta oh ICEE Yeah, 98 00:05:08.560 --> 00:05:12.439 the teeth often have these bulbous crowns, and on an 99 00:05:12.600 --> 00:05:17.000 X ray the pulp chambers inside the teeth look completely obliterated, 100 00:05:17.160 --> 00:05:19.240 just filled in with faulty dentin. 101 00:05:19.519 --> 00:05:23.800 It's fascinating how a single genetic misfire just cascades like that. 102 00:05:24.240 --> 00:05:26.959 Ectodermal dysplasia is another one that caught my eye. The 103 00:05:27.040 --> 00:05:30.120 notes say these patients are often missing teeth and missing hair. 104 00:05:30.839 --> 00:05:32.240 I had to think about that for a second, but 105 00:05:32.279 --> 00:05:33.959 it makes perfect sense, right, because. 106 00:05:33.680 --> 00:05:36.800 Both teeth and hair developed from the ectoderm, the outermost 107 00:05:36.839 --> 00:05:38.040 tissue layer of the embryo. 108 00:05:38.240 --> 00:05:42.040 Exactly the foundational blueprint is flawed. We also see congenital 109 00:05:42.079 --> 00:05:46.040 impacts in down syndrome or trisomy twenty one, which often 110 00:05:46.079 --> 00:05:49.639 presents with missing teeth in a thickened tongue, or pure 111 00:05:49.720 --> 00:05:52.040 robin syndrome in neonates. 112 00:05:51.560 --> 00:05:56.120 Oh purebent is critical for airway management. The infant has micrognathia, 113 00:05:56.160 --> 00:05:58.360 an incredibly small jaw right and. 114 00:05:58.319 --> 00:05:59.959 Because the jaw is so small, there's just no room 115 00:06:00.040 --> 00:06:01.759 for the tongue, so it falls back into the airway. 116 00:06:01.839 --> 00:06:04.079 That's a condition called glossoptosis. 117 00:06:03.439 --> 00:06:05.879 Right spot on glossoptosis. 118 00:06:06.120 --> 00:06:08.240 Okay, So We've tracked how the whole body sets off 119 00:06:08.279 --> 00:06:11.160 alarms in the mouth, But what happens when the systemic 120 00:06:11.199 --> 00:06:13.639 engine is running totally fine and you just have one 121 00:06:14.199 --> 00:06:17.959 highly localized alarm, like a single strange spot on a 122 00:06:18.040 --> 00:06:18.839 jaw radiograph. 123 00:06:19.199 --> 00:06:22.199 This is where we move from systemic medicine into localized 124 00:06:22.360 --> 00:06:27.199 diagnostic imaging. You really have to learn the visual vocabulary 125 00:06:27.240 --> 00:06:28.439 of dental anomalies here. 126 00:06:28.519 --> 00:06:31.120 Some are pretty obvious, I guess, like attrition. 127 00:06:31.040 --> 00:06:33.839 Right attrition where a patient who severely grinds their teeth 128 00:06:33.920 --> 00:06:37.199 leaves flat polished ware of facets on the enamel, or 129 00:06:37.199 --> 00:06:40.800 a Messiodander's, which is just an extra supernumerary tooth popping 130 00:06:40.879 --> 00:06:42.480 up right between the upper front teeth. 131 00:06:42.519 --> 00:06:44.839 And you have densin dente, which sounds like a total 132 00:06:44.879 --> 00:06:47.519 horror movie but is literally just a tooth developing within 133 00:06:47.600 --> 00:06:50.519 a tooth, usually in the upper lateral incisors, and a 134 00:06:50.600 --> 00:06:55.000 hypersomintosis an overgrowth of root tissue, which, wait, that ties 135 00:06:55.079 --> 00:06:56.879 right back to Paget's disease, doesn't it. 136 00:06:56.680 --> 00:06:59.439 It absolutely does. The unorganized bone growth of pagets often 137 00:06:59.439 --> 00:07:03.800 triggers that excess cementum on the roots. But the real 138 00:07:03.839 --> 00:07:06.040 diagnostic tests are the cysts and tumors. 139 00:07:06.319 --> 00:07:09.319 Visual clues are everything here, but honestly, looking at these notes, 140 00:07:09.360 --> 00:07:13.199 some of them seem basically impossible to tell apart. For example, 141 00:07:13.360 --> 00:07:16.920 a globular maxillary cyst is an inverted pear shape between 142 00:07:16.920 --> 00:07:18.600 the upper lateral incisor and the. 143 00:07:18.600 --> 00:07:20.639 Canine right very distinct shape. 144 00:07:20.639 --> 00:07:23.720 And an analobe blustoma is this aggressive tumor that looks 145 00:07:23.759 --> 00:07:27.000 like a cluster of soap bubbles in the bone. But 146 00:07:27.079 --> 00:07:29.800 then I'm looking at a periapical syst versus a dental 147 00:07:29.839 --> 00:07:32.600 granuloma on an X ray. They both just look like 148 00:07:32.759 --> 00:07:34.920 dark circles at the root tip of a dead tooth. 149 00:07:35.399 --> 00:07:37.040 How am I supposed to know which is which? 150 00:07:37.199 --> 00:07:40.279 Well you can't wait, really, not just by looking the radiograph. No, 151 00:07:40.839 --> 00:07:45.000 they're radiographically identical. The only definitive way to distinguish them 152 00:07:45.319 --> 00:07:48.480 is to biopsy the tissue under a microscope. Oh wow, Yeah, 153 00:07:48.480 --> 00:07:50.800 If the lesion has an epitheal lining, it's a cyst. 154 00:07:51.120 --> 00:07:53.920 If it's just a solid mass of fibrous connective tissue, 155 00:07:54.040 --> 00:07:55.079 it's a granuloma. 156 00:07:55.120 --> 00:07:58.079 Good to know. I'm not just missing something obvious. But 157 00:07:58.120 --> 00:08:02.199 here's a dangerous one. I saw in the material the cementoma, 158 00:08:02.360 --> 00:08:05.160 it shows up as a dark radiolucent spot at the 159 00:08:05.240 --> 00:08:08.399 root apex of the lower front teeth. If it looks 160 00:08:08.399 --> 00:08:12.279 exactly like a periodical abscess from an necrotic tooth, how 161 00:08:12.279 --> 00:08:14.720 do you prevent a well meaning dentist from drilling in 162 00:08:14.759 --> 00:08:17.279 and doing a totally unnecessary root canal. 163 00:08:17.319 --> 00:08:21.000 By understanding the mechanism of where the lesion actually comes from. 164 00:08:21.399 --> 00:08:26.040 A cementoma or a periapical cemental dysplasia arises from the 165 00:08:26.079 --> 00:08:29.000 bone itself, not from a dead nerve inside the tooth. 166 00:08:29.079 --> 00:08:29.279 Aw. 167 00:08:29.399 --> 00:08:31.399 Okay, do you just perform a simple cold or electrical 168 00:08:31.439 --> 00:08:34.159 pulp vitality test if the tooth reex normally the nerve 169 00:08:34.279 --> 00:08:36.240 is alive. That tells you it's a cemon tuna. And 170 00:08:36.279 --> 00:08:39.399 the most important clinical step here, what's that? Do absolutely nothing? 171 00:08:39.480 --> 00:08:42.399 It requires zero treatment and will eventually calcify and turn 172 00:08:42.440 --> 00:08:43.919 white on the X ray all by itself. 173 00:08:44.039 --> 00:08:46.919 Man, a quick vitality test saves a lot of unnecessary drilling. 174 00:08:47.120 --> 00:08:49.759 Speaking of those X rays, the notes heavily emphasize the 175 00:08:49.840 --> 00:08:52.360 rule of occult diseases. What's the protocol there? 176 00:08:52.480 --> 00:08:55.600 It's a very strict rule of radiation safety. You never 177 00:08:55.679 --> 00:08:58.639 expose a patient to radiation just to go fishing for 178 00:08:58.720 --> 00:09:02.440 hidden or a cult cysts or tumors if they have 179 00:09:02.559 --> 00:09:03.759 zero clinical symptoms. 180 00:09:03.840 --> 00:09:06.840 So no random X ray is just to check exactly. 181 00:09:07.000 --> 00:09:10.000 The only exception is screening for cavities because decay is 182 00:09:10.039 --> 00:09:13.080 just so universally common. However, once you take an X 183 00:09:13.159 --> 00:09:16.399 ray for a valid reason, you are legally and ethically 184 00:09:16.440 --> 00:09:21.120 obligated to meticulously evaluate the entire image for those hidden lesions. 185 00:09:21.279 --> 00:09:24.639 Right and remember, for anyone studying this, the dentist, not 186 00:09:24.720 --> 00:09:27.720 the hygienis, not the assistant, is the only one who 187 00:09:27.720 --> 00:09:29.759 can legally prescribe those radiographs. 188 00:09:29.799 --> 00:09:32.879 Absolutely, and doing it digitally cuts the radiation exposure by 189 00:09:32.879 --> 00:09:35.559 fifty to eighty percent anyway, Plus, if you want to 190 00:09:35.600 --> 00:09:38.240 actually see the crystal bone to check for period dombal disease, 191 00:09:38.600 --> 00:09:39.960 you have to take vertical bite wings. 192 00:09:40.000 --> 00:09:42.720 Okay, getting the diagnosis is only half the battle. Right now, 193 00:09:42.759 --> 00:09:46.080 you have a living, breathing, potentially medically compromised human sitting 194 00:09:46.120 --> 00:09:48.080 in your chair. How do we safely manage them? 195 00:09:48.399 --> 00:09:51.759 You rely on physiological protocols. If a patient goes into 196 00:09:51.799 --> 00:09:56.799 cardiac arrest, it's caab compressions airway breathing thirty compressions to 197 00:09:56.840 --> 00:09:57.440 two breaths. 198 00:09:57.679 --> 00:10:01.200 And what if a diabetic patient becomes hypoglycemic, like there 199 00:10:01.200 --> 00:10:04.279 are blood sugar crashes, they get confused, cold, sweaty. 200 00:10:04.519 --> 00:10:07.679 You need fast acting carbs immediately, a third of a 201 00:10:07.679 --> 00:10:10.360 cup of orange juice every five minutes until they stabilize. 202 00:10:10.480 --> 00:10:14.240 Got it. For seizure patients, the priority is preventing self harm, 203 00:10:14.320 --> 00:10:16.960 so you use bite blocks. For pregnant patients, if they 204 00:10:17.039 --> 00:10:19.840 need elective work, you aim for the second and third trimesters. 205 00:10:20.399 --> 00:10:26.279 But the protocols for radiation patients this is incredibly heavy. 206 00:10:26.360 --> 00:10:27.320 It is very serious. 207 00:10:27.519 --> 00:10:31.159 The notes say you absolutely must extract any unsalvagable teeth 208 00:10:31.320 --> 00:10:34.799 before radiation therapy begins to the head and neck. Why 209 00:10:34.879 --> 00:10:36.360 is the timing so rigid. 210 00:10:36.360 --> 00:10:40.639 Because radiation fundamentally and permanently damages the blood vessels in 211 00:10:40.679 --> 00:10:44.039 the bone, particularly in the dense mandible. If you pull 212 00:10:44.039 --> 00:10:46.720 a tooth after radiation, the bone just has no blood 213 00:10:46.720 --> 00:10:48.600 supply to heal the extraction socket. 214 00:10:48.799 --> 00:10:50.879 Oh man, So it just doesn't heal at all. 215 00:10:50.960 --> 00:10:53.679 It doesn't. The bone simply dies and gets infected. That's 216 00:10:53.759 --> 00:10:57.039 called osteo radiotocrosis. And you face a very similar risk 217 00:10:57.120 --> 00:11:01.080 with patients taking ivy bisphosphonates for us zeoporosis or cancer. 218 00:11:01.559 --> 00:11:04.000 The bones healing mechanism is zerrely compromised. 219 00:11:04.279 --> 00:11:07.120 You really have to understand the microscopic mechanisms to keep 220 00:11:07.159 --> 00:11:12.080 patients safe, which actually brings us to pharmacology. Drugs binding 221 00:11:12.080 --> 00:11:14.519 to receptors to make things happen. I know we have 222 00:11:14.559 --> 00:11:19.159 different bonds electrostatic, ionic bonds, hydrogen bonds, Drugs that open 223 00:11:19.240 --> 00:11:22.720 ion channels or use g proteins for second messengers. 224 00:11:22.480 --> 00:11:24.720 Right, and some even bypass all of that and act 225 00:11:24.759 --> 00:11:28.200 as nucleus receptors to alter DNA transcription directly. And at 226 00:11:28.240 --> 00:11:31.480 those receptors, drugs act as either agonists which trigger an 227 00:11:31.480 --> 00:11:34.000 effect or antagonists which block it. 228 00:11:34.200 --> 00:11:36.720 Right, And if an antagonist is competitive, it means it's 229 00:11:36.720 --> 00:11:39.679 just fighting for the exact same parking spot as the agonist. 230 00:11:40.000 --> 00:11:41.600 So if you flood the system with enough of the 231 00:11:41.600 --> 00:11:43.559 agonist drug, you can overpower. 232 00:11:43.080 --> 00:11:44.480 The blocker perfectly stated. 233 00:11:44.720 --> 00:11:47.840 But I'm looking at the adrenergics, the drugs that mimic 234 00:11:47.879 --> 00:11:51.480 our fight or flight sympathetic nervous system. I get how 235 00:11:51.559 --> 00:11:55.080 isoproteronal is a powerful agonist that dilates the bronchioles and 236 00:11:55.120 --> 00:11:58.080 the lungs. But how does methyl dopo work for high 237 00:11:58.120 --> 00:12:01.480 blood pressure? The notes say it creates a false transmitter. 238 00:12:01.840 --> 00:12:05.000 Mythyl dopa is brilliant. Actually, it essentially acts as a 239 00:12:05.039 --> 00:12:07.639 trojan horse. It gets taken up by the nerve endings 240 00:12:07.840 --> 00:12:10.000 and converted into a fake version of neropine. 241 00:12:10.039 --> 00:12:11.840 Front wait, a fake version. 242 00:12:12.039 --> 00:12:14.759 Yeah, And this fake neurotransmitter gets stored in the nerve 243 00:12:15.399 --> 00:12:17.799 so when the nervous system fires to raise blood pressure, 244 00:12:18.200 --> 00:12:21.559 it releases this fake inactive chemical instead of the real thing. 245 00:12:22.159 --> 00:12:25.399 It effectively keeps the blood pressure lowered. It's heavily used 246 00:12:25.440 --> 00:12:28.000 for hypertension, especially in patients with kidney damage. 247 00:12:28.080 --> 00:12:32.200 That is a wildly elegant mechanism. Now contrast that with 248 00:12:32.240 --> 00:12:37.519 something blunt, like a neuromuscular blocker. Yeah, sucunal coline oh signalochline. 249 00:12:37.720 --> 00:12:42.240 It's a depolarizing blocker used for endotracheal intubation. It forces 250 00:12:42.240 --> 00:12:45.320 the muscle receptor to fire once, causing a brief twitch, 251 00:12:45.639 --> 00:12:47.240 and then completely paralyzes it. 252 00:12:47.279 --> 00:12:49.600 But there is a massive danger there, huge. 253 00:12:49.399 --> 00:12:53.279 Danger if a patient genetically lacks the enzyme's pseudocolon esterrays 254 00:12:53.360 --> 00:12:56.200 to break that drug down, they will suffer from prolonged 255 00:12:56.240 --> 00:12:58.440 respiratory paralysis. They won't be able to breathe on their 256 00:12:58.480 --> 00:12:59.720 own for a very long time. 257 00:13:00.120 --> 00:13:02.879 Terrifying, but essential to know if you're taking the boards. 258 00:13:03.919 --> 00:13:07.720 Let's talk about pain management and drug interactions. We know 259 00:13:07.960 --> 00:13:12.200 mixing alcohol with certain drugs causes the disulfuum ethanol reaction, 260 00:13:12.559 --> 00:13:16.919 severe vomiting, headache, plunging blood pressure. But in dentistry we 261 00:13:17.000 --> 00:13:21.360 constantly combine drugs intentionally for pain, like hydro codone and ibuprofen. 262 00:13:21.440 --> 00:13:22.879 Why give two different. 263 00:13:22.519 --> 00:13:25.720 Pills because you are attacking the pain pathway at two 264 00:13:25.840 --> 00:13:28.159 completely different anatomical locations. 265 00:13:28.159 --> 00:13:31.080 So it's like a military flank attack like that. Exactly, 266 00:13:31.200 --> 00:13:34.799 the narcotic, the hydrocodone, crosses into the central nervous system 267 00:13:34.840 --> 00:13:36.759 to hit the brain and just you know, shut off 268 00:13:36.759 --> 00:13:41.600 the alarm bells. Meanwhile, the nsaid the ibuprofen stays in 269 00:13:41.639 --> 00:13:44.799 the peripheral nervous system, traveling to the actual site of 270 00:13:44.840 --> 00:13:47.240 the surgery to put out the inflammatory fire at the 271 00:13:47.240 --> 00:13:47.919 tissue level. 272 00:13:47.960 --> 00:13:50.399 That's a great way to visualize it, and a clinical bonus, 273 00:13:50.679 --> 00:13:53.000 narcotics do not affect blood clotting. Go if you have 274 00:13:53.039 --> 00:13:55.919 a patient on blood thinners like warker and narcotics are safe, 275 00:13:56.000 --> 00:13:58.720 and if an overdose occurs with a narcotic, you immediately 276 00:13:58.840 --> 00:14:01.960 use a reversal agent like mel mephine or nultrexone to 277 00:14:02.039 --> 00:14:03.559 knock the drug off the receptors. 278 00:14:03.919 --> 00:14:07.480 Okay, the patient is stabilized, their numb they're safe. Now 279 00:14:07.519 --> 00:14:09.799 we put on our engineering hats to rebuild the teeth. 280 00:14:10.200 --> 00:14:13.240 Let's jump into prosodontics and operative dentistry. 281 00:14:13.399 --> 00:14:18.120 Let's do it. When designing a removable partial denture or RPD, 282 00:14:18.279 --> 00:14:22.639 the foundation is applegates rules for Kennedy classifications. One major 283 00:14:22.720 --> 00:14:25.440 rule is you always classify the arch after any planned 284 00:14:25.440 --> 00:14:29.120 extractions are completed. It completely dictates the design makes sense. 285 00:14:29.320 --> 00:14:32.399 And if you are building a maxillary major connector using 286 00:14:32.440 --> 00:14:35.600 ap straps across the roof of the mouth, those straps 287 00:14:35.679 --> 00:14:39.360 must be at least fifteen millimeters apart for structural integrity, 288 00:14:40.000 --> 00:14:42.720 and they must never cross onto the vibrating soft palette 289 00:14:42.960 --> 00:14:44.519 where the patient just won't tolerate it. 290 00:14:44.720 --> 00:14:48.120 What about complete dentures? The primary support comes from the 291 00:14:48.159 --> 00:14:51.159 residual bony ridge and the hard palette, but the notes 292 00:14:51.159 --> 00:14:54.159 say you must provide relief over the median palatal raph. 293 00:14:54.480 --> 00:14:57.440 I'm trying to picture this. Why would a perfectly fitted 294 00:14:57.519 --> 00:15:00.200 denture suddenly start rocking like a bad restaurant. 295 00:15:00.399 --> 00:15:02.679 Because the medium pelladal raft is the suture line running 296 00:15:02.759 --> 00:15:04.120 right down the middle of the roof of the mouth. 297 00:15:04.720 --> 00:15:07.759 The tissue there is paper thin over solid bone. Oh 298 00:15:07.799 --> 00:15:11.039 I see yeah, whereas the tissue everywhere else is squishy 299 00:15:11.039 --> 00:15:14.240 and resilient. So when the patient bites down, the denture 300 00:15:14.279 --> 00:15:17.399 sinks into the squishy tissue but bottoms out hard on 301 00:15:17.399 --> 00:15:20.080 that middle raft, causing it to rock. You have to 302 00:15:20.120 --> 00:15:22.600 carve out a relief space in the denture base to 303 00:15:22.639 --> 00:15:24.799 accommodate that difference in tissue yield. 304 00:15:24.879 --> 00:15:26.799 That makes perfect sense. You have to account for the 305 00:15:26.799 --> 00:15:30.360 tissue dynamics under pressure. This also brings up the VDO, 306 00:15:30.480 --> 00:15:34.120 the vertical dimension of occlusion. Why is losing that vertical 307 00:15:34.159 --> 00:15:35.720 height such a disaster for patient? 308 00:15:36.039 --> 00:15:39.480 If the VIDO decreases, meaning the patient's upper and lower 309 00:15:39.559 --> 00:15:43.039 jaws are overclosing because the teat or dentures are worn down, 310 00:15:43.360 --> 00:15:46.360 the facial mechanics just collapse. The lips lose their border, 311 00:15:46.360 --> 00:15:49.279 and the face scrunches up. That sounds uncomfortable, It is 312 00:15:49.960 --> 00:15:53.519 mechanically the patient will chronically bite their cheeks. Chemically, the 313 00:15:53.600 --> 00:15:56.279 overclosure creates deep folds at the corners of the mouth 314 00:15:56.320 --> 00:16:00.440 where saliva pools, causing a constant, painful fungal infection called 315 00:16:00.519 --> 00:16:01.519 angular kilitis. 316 00:16:02.120 --> 00:16:06.240 Form truly dictates function. This is exactly why over dentures 317 00:16:06.240 --> 00:16:09.200 are so prized. Right If you can keep just a 318 00:16:09.240 --> 00:16:12.639 few retained tooth roots in the bone underneath the denture, 319 00:16:12.919 --> 00:16:16.639 it preserves the alveolar bone and stops that vertical collapse exactly. 320 00:16:16.679 --> 00:16:18.840 And when we're picking the fake teeth, we use the 321 00:16:18.840 --> 00:16:21.679 golden proportion one point six eight to one point zero 322 00:16:21.759 --> 00:16:25.480 to zero point six, so the teeth look mathematically natural 323 00:16:25.480 --> 00:16:26.679 as they fade into the smile. 324 00:16:26.840 --> 00:16:29.840 And we use plastic teeth, not porcelain, so they chemically 325 00:16:29.879 --> 00:16:31.240 bond to the acrylic base. 326 00:16:31.600 --> 00:16:35.559 Right now, when we shift to fixed partial dentures bridges 327 00:16:35.559 --> 00:16:39.559 that are cemented in booth, even the temporary plastic bridge 328 00:16:39.639 --> 00:16:42.960 has to do two critical jobs. It must insulate the 329 00:16:43.000 --> 00:16:45.480 living pulp from hot and cold, and it must hold 330 00:16:45.519 --> 00:16:48.720 positional stability with tight inter proximal contacts so. 331 00:16:48.639 --> 00:16:51.240 The adjacent teeth don't drift While you're waiting for the 332 00:16:51.279 --> 00:16:53.960 lab to make the final ceramic bridge exactly and the 333 00:16:54.000 --> 00:16:56.440 design of the pontic, the faked tooth suspended in the 334 00:16:56.440 --> 00:16:59.200 middle of the bridge can make or break the tissue health. 335 00:16:59.600 --> 00:17:02.200 The material says to never use a saddle pontic, but 336 00:17:02.279 --> 00:17:05.000 it looks natural because it straddles both sides of the gumbridge. 337 00:17:05.079 --> 00:17:06.000 So why is it banned? 338 00:17:06.319 --> 00:17:10.799 Because it creates a microscopic concave cave underneath it. It is 339 00:17:10.880 --> 00:17:15.160 physically impossible for the patient to run floss under saddle pontic. 340 00:17:15.839 --> 00:17:20.160 Plaque accumulates instantly, causing massive chronic tissue inflammation. 341 00:17:20.480 --> 00:17:21.880 So what do you use instead? 342 00:17:22.079 --> 00:17:25.119 In non esthetic zones like the lower molars, use a 343 00:17:25.160 --> 00:17:28.720 hygienic or fish belly pontic. It leaves a three millimeter 344 00:17:28.880 --> 00:17:31.559 open gap above the tissue, so a toothbrush can sweep 345 00:17:31.640 --> 00:17:32.200 right under it. 346 00:17:32.359 --> 00:17:35.000 We see that same demand for exact geometry and operative 347 00:17:35.039 --> 00:17:38.640 dentistry like filling cavities, But first you have to understand 348 00:17:38.680 --> 00:17:41.640 the decay itself carries happens in zones. Zone one is 349 00:17:41.680 --> 00:17:45.359 normal dentin, Zone two is subtransparent, dentin. Zone three is 350 00:17:45.400 --> 00:17:46.759 transparent dentin right. 351 00:17:46.680 --> 00:17:49.079 And the key here is that zones two and three 352 00:17:49.200 --> 00:17:52.400 are demineralized but they do not contain bacteria. 353 00:17:52.559 --> 00:17:55.119 And because they are bacteria free, if you seal them up, 354 00:17:55.160 --> 00:17:58.240 they are entirely capable of remineralizing. You don't actually have 355 00:17:58.279 --> 00:18:00.599 to drill them away. When you do d say for 356 00:18:00.640 --> 00:18:03.839 a class two silver amalgam, the microscopic geometry is vital. 357 00:18:03.880 --> 00:18:06.680 You only bevel the deep gingible floor of the prep. 358 00:18:06.759 --> 00:18:09.160 If that margin sits on enamel, why what does the 359 00:18:09.160 --> 00:18:10.440 bevil actually do well. 360 00:18:10.559 --> 00:18:14.240 Enamel is made of millions of tiny crystalline rods. If 361 00:18:14.240 --> 00:18:17.240 your drill leaves short, unsupported rods at the edge of 362 00:18:17.240 --> 00:18:20.559 the filling, the moment the patient bites down on that amalgam, 363 00:18:20.960 --> 00:18:23.400 those rods will shatter, breaking the seal. 364 00:18:23.640 --> 00:18:28.119 Ah, So the bevel sweeps away the fragile, unsupported rods exactly. 365 00:18:28.400 --> 00:18:30.279 And if you are deeper down on the root cementum, 366 00:18:30.480 --> 00:18:33.079 there are no rods, so no bevel is needed. 367 00:18:33.240 --> 00:18:35.160 And while you are cutting that prep, you have to 368 00:18:35.279 --> 00:18:37.720 use water as a bird coolant. If you just blast 369 00:18:37.759 --> 00:18:41.400 it with air, you dehydrate the dentin. The fluid inside 370 00:18:41.440 --> 00:18:46.079 the microscopic dentin tubules evaporates, creating a vacuum that literally 371 00:18:46.200 --> 00:18:50.480 sucks the nerve endings. The odonto blasts up into the tubules. 372 00:18:49.960 --> 00:18:52.640 Which it causes massive post operative hypersensitivity. 373 00:18:52.720 --> 00:18:56.759 Sounds brutal, which perfectly sets up our final foundational concept. 374 00:18:57.319 --> 00:19:00.759 You can engineer a mathematically flawless amalgam or bridge, but 375 00:19:00.839 --> 00:19:03.599 it means absolutely nothing if the ground underneath it is sinking. 376 00:19:04.119 --> 00:19:06.720 We have to discuss periodontics. 377 00:19:05.880 --> 00:19:10.319 The biological bedrock. When a patient had deep periodontal pockets, 378 00:19:10.559 --> 00:19:13.440 surgery is often the answer, and a foundational cut is 379 00:19:13.480 --> 00:19:14.759 the internal bevel incision. 380 00:19:14.839 --> 00:19:17.119 I've always thought of this like tailoring a fine suit. 381 00:19:17.359 --> 00:19:20.920 That's a highly accurate analogy with an internal bevel incision. 382 00:19:21.319 --> 00:19:24.839 Your blade removes the diseased, frayed lining on the inside 383 00:19:24.839 --> 00:19:28.480 of the pocket, but it completely concerns the healthy, pristine 384 00:19:28.599 --> 00:19:31.960 outer fabric of the gums. It creates a sharp, clean 385 00:19:32.079 --> 00:19:35.039 margin that you can stitch tightly back against the bone. 386 00:19:35.240 --> 00:19:39.319 And if the tissue contours are bulky and uncleansible, then 387 00:19:39.400 --> 00:19:40.119 we reshape. 388 00:19:40.160 --> 00:19:43.640 We use a gingy voplasty to recontour the soft tissue 389 00:19:43.680 --> 00:19:47.400 for physiological form. Note this doesn't eliminate pockets, it just 390 00:19:47.480 --> 00:19:50.240 improves the shape. And for bone, if the bone itself 391 00:19:50.279 --> 00:19:53.400 is bulky, we use an osteoplasty to reshape the non 392 00:19:53.400 --> 00:19:57.079 supporting alveolear bone, being very careful not to damage the 393 00:19:57.079 --> 00:19:58.920 bone actually attached to the tooth root. 394 00:19:59.400 --> 00:20:01.200 But before when we make a single cut, we have 395 00:20:01.240 --> 00:20:04.200 to measure the damage. The periodonal probe is arguably the 396 00:20:04.200 --> 00:20:07.119 most important instrument in the tray because it calculates clinical 397 00:20:07.119 --> 00:20:08.240 attachment loss right. 398 00:20:08.359 --> 00:20:10.920 Pocket depth alone is deceptive. If a patient has a 399 00:20:10.920 --> 00:20:14.160 four milimeters pocket, but their gums have receded three millimeters 400 00:20:14.200 --> 00:20:17.160 down the route, their total clinical attachment loss is actually 401 00:20:17.200 --> 00:20:19.920