张三锡曰∶《内经》曰中央黄色，入通于脾，开窍于口。
又口属上焦心肺，有病则口亦病。胃中有邪热，亦炎上作楚。原其所由，七情烦扰，五味过伤，皆能致此。
是以肝热则口酸，心热则口甜，肺热则口辛，肾热则口咸。有口淡者，知胃热也。又有谋虑不决，肝移热于
胆而口苦者；有脾胃气弱。木乘土位而口酸者；有膀胱移热于小肠，膈肠不便，上为口糜者，故口疮舌破，
炎上之故，不独脾也。而丹溪又曰∶劳役过度，虚火上炎，服凉药不效，属中气虚。虚火炎上，游行无制，
用炮姜、理中汤。理可见矣。
赵养葵曰∶口疮者，上焦实热，中焦虚寒，下焦阴火，各经传变，当分别而治之。如发热作渴饮冷，实
热也，轻则补中益气，重则六君子。饮食少思，大便不实，中气虚也，用人参理中汤。手足逆冷，肚腹作痛，
中气虚寒，用附子理中汤。晡热内热，血虚也，用八物加丹皮、五味、麦冬。发热作渴，唾痰，小便频数，
肾水虚也，用八味。日晡发热，或从小腹起，阴虚也，用四物加参、术、五味、麦冬；不应，用加减八味丸。
若热来复去，昼见夜伏，夜见昼伏，不时而动，或无定处，或从肺起，乃无根之火也，亦用前丸，及十全
大补加麦冬、五味，更以附子末唾津调，涂涌泉穴。若概用寒凉，为害非轻。
王节斋曰∶鼻塞不闻香臭，或但遇寒月多塞，或略感风寒便塞；不时举发者，世俗皆以为肺寒，而用
解表通利辛温之药。殊不知此是肺经素有火邪，火郁甚则喜得热而恶见寒。故遇寒便塞，遇感便发也。治法，
清肺降火为主，而佐以通气之剂。若如常鼻塞不闻香臭者，再审其平素，只作肺热治之，清金泻火消痰，或丸
药噙化，或末药轻调缓服，久服无不效矣。其原无旧症，一时偶感者，自作风寒调治。鼻 者，由饮酒血热
熏肺，外遇风寒，血凝不散也；亦有非饮酒而自
赤者，肺风血热之故。其鼻疮、鼻痔、鼻痈，皆因肺热所致，但有浅深之不同，受病之有异。日久不已，
经成 肉，如枣塞鼻中。丹溪曰∶胃中有食积热痰流注，故浊凝结而生 肉也。鼻 宜化滞生新，四物加
片芩、红花、茯苓、陈皮、甘草、生姜等药，调五灵末服，如气弱加黄 。
齿属肾，上下龈属阳明，上龈阳明胃，下龈阳明大肠。凡动摇袒脆而痛，或不痛，或出血，或不出血，全
具如欲落之状者，皆属于肾。龈肿不动，溃烂痛秽者，皆属阳明。或诸经错杂之邪，与外因为患，俱分虚实
治之。肾经寒者，安肾丸、还少丹，重则八味丸主之。如齿痛摇动，肢体倦怠，饮食少思者，脾胃亏损之症，
用安肾丸，补中益气汤并服。如喜寒恶热者，乃胃血伤也，清胃汤。若恶寒喜热者，胃气伤也，补中益气汤。
凡齿痛遇劳即发，或午后甚者，口渴而黧，或遗精者，皆脾胃虚热，补中益气，用六味丸或十全大补汤。
若齿龈肿痛， 连腮颊，此胃经风热，犀角升麻汤。若善饮者，齿痛，颊 肿，此胃经湿热，清胃汤加葛根，
或解酲汤。海藏云∶齿龈臭秽不可近，当作阳明蓄血治，桃仁承气汤为末，蜜丸服之。间有齿缝出血者，余以
六味地黄汤加骨碎补，大剂一服即瘥。间有不瘥者，肾中火衰也，本方加五味子、肉桂可也。
王节斋曰∶牙床肿痛，齿痛动摇，或黑烂脱落，世人皆作肾虚治，殊不知此属阳明湿热症也。盖齿虽
属肾，而生于牙床，上下床属阳明大肠与胃，犹木生于土也。肠胃伤于美酒浓味，膏粱甘滑之物，以致湿热
上攻，则牙床不清，而为肿为痛，或出血，或生虫，由是齿不得安，而动摇黑烂脱落也。治宜泻阳明之湿热，
则牙床清宁而齿固矣。
张介宾曰∶口苦口酸等症，《原病式》皆指为热，不知口
苦未必因心火，口淡未必尽胃热。凡思虑、劳倦、色欲，多有口苦舌燥，饮食无味。或因心脾虚，肝胆邪
溢而为苦；或因肝肾虚，真阴不足而为燥。凡口淡，或大劳、大汗、大泄、大病后，多有此。若无火症火
脉，皆劳伤之症。
凡口渴与口干不同∶渴因火燥有余，多实热，干因津液不足，为阴虚。然渴有实热之渴，亡阴之渴。凡
大泻、大汗、大劳、大病、新产、痈疽后，悉由亡阴水亏所致。
舌苔黑，有虚火、实火之别∶实热之黑，必兼红紫干渴或多芒刺；若沉黑少红，而带润滑，非实证也。
六脉细弱，形困气倦，最为虚候，必寒水乘心，火不归原之病，治标即死。
鼻塞由风寒者，多喷嚏，多在太阳，宜辛散。火炎上焦，出自心肺，黄芩知母汤。火甚多出阳明，微
兼头痛，竹叶石膏汤。大约常塞者多火，暴塞者多风，以此辨之。
鼻渊由太阳督脉之火上连于脑，多由湿热上熏，津汁溶溢而下，有作臭者，古方用辛散，不若但清
阴火，而兼以滋阴，为高者抑之之法。若流渗既久，液道不能扃固，故新病多因于热。漏泄既多，伤其髓海，
则气虚于上，多见头脑隐痛，及眩运不宁等症，此非补阳不可，宜十全大补汤。
阳明热壅牙痛，清胃散。肾阴虚，为热渴，玉女煎。外治，辛温可散热，三香散、赴筵散。虫牙蛀空
痛，巴豆丸。牙缝出血，胃火所致；亦有阴虚于下，格阳于上，六脉微细，血出不止，手足厥冷，速宜镇阴
煎。肾虚症当辨寒热，热六味丸，寒八味丸，通加骨碎补丸，妙。若齿牙浮动脱落，牙缝出血，而口不臭，
亦无痛，肾中阳虚，安肾丸。走马牙疳，腐烂脱落，速内泻阳明之火，外宜冰白散、三仙散，或用干枣
烧存性，同枯矾敷之效。
凡齿脆、摇动疏豁，或突而不实，宜补肾，若因劳酒色，
齿有浮突之意，轻轻咬实，渐咬渐齐。或日行二三次，而根自固。于小解时，先咬定牙根，则肾气可摄。非
但固精，亦能坚齿。又夜晚漱洗，或饭后必漱齿，至老坚白不衰。
张三锡说：《内经》记载，中央对应黄色，内通于脾，开窍于口。
另外，口部属于上焦心肺的范畴，如果心肺有病，口部也会随之发病。胃中有邪热，也会向上炎蒸导致疼痛不适。推究其起因，七情（喜、怒、忧、思、悲、恐、惊）烦扰，五味（酸、苦、甘、辛、咸）过伤，都能导致这种情况。
因此，肝热则口觉酸味，心热则口觉甜味，肺热则口觉辛辣味，肾热则口觉咸味。口淡无味的人，可知是胃热所致。又有因谋虑不决，肝将热邪移注于胆而口苦的；有因脾胃气弱，木气乘克土位而口酸的；有因膀胱将热邪移注于小肠，膈肠不通畅，上行导致口腔糜烂的，所以口疮舌破，这是火热炎上的缘故，不仅仅在于脾脏。而朱丹溪又说：过度劳役，虚火上炎，服用凉药无效，属于中气虚弱。虚火炎上，游行无制，应用炮姜、理中汤。道理就显而易见了。
赵养葵说：口疮，是上焦实热，中焦虚寒，下焦阴火，各经传变，应当分别治疗。如发热口渴想喝冷水，是实热，轻症用补中益气汤，重症用六君子汤。饮食减少不想吃，大便不成形，是中气虚，用人参理中汤。手足逆冷，肚腹疼痛，是中气虚寒，用附子理中汤。下午发热体内发热，是血虚，用八物汤加牡丹皮、五味子、麦冬。发热口渴，吐痰，小便频数，是肾水虚，用八味丸。日晡时发热，或从小腹起，是阴虚，用四物汤加人参、白术、五味子、麦冬；若无效，用加减八味丸。若热来复去，白天出现晚上潜伏，晚上出现白天潜伏，不时而动，或没有固定位置，或从肺部发起，这是无根之火，也用前面的丸药，以及十全大补汤加麦冬、五味子，再用附子末唾津调和，涂抹涌泉穴。如果一概使用寒凉药物，危害不轻。
王节斋说：鼻塞闻不到香臭，或者只在寒冷月份多塞，或者稍微感受风寒就塞；不时发作的，世俗都认为是肺寒，而使用解表通利的辛温药物。殊不知这是肺经素来有火邪，火郁结严重时喜欢热而厌恶寒。所以遇寒便塞，遇感便发。治疗方法，以清肺降火为主，辅以通气之剂。如果像平常一样鼻塞闻不到香臭，再审查其平素情况，只按肺热治疗，清金泻火消痰，或用丸药含化，或用散药轻轻调缓服用，久服无不有效。其原本无旧疾，一时偶然感受的，自然按风寒调理。鼻赤，是由饮酒后血热熏肺，外遇风寒，血凝不散所致；也有不饮酒而自红的，是肺风血热的缘故。鼻疮、鼻痔、鼻痈，都是因为肺热所致，只是深浅不同，受病有异。日久不止，经久成赘肉，如枣子堵塞鼻中。丹溪说：胃中有食积热痰流注，所以浊凝结而生赘肉。鼻息肉宜化滞生新，用四物汤加黄芩、红花、茯苓、陈皮、甘草、生姜等药，调五灵脂末服用，如果气弱加黄芪。
牙齿属于肾，上下牙龈属于阳明经，上牙龈属阳明胃，下牙龈属阳明大肠。凡是牙齿动摇脆弱而痛，或不痛，或出血，或不出血，完全具备像要脱落的样子，都属于肾。牙龈肿胀但不松动，溃烂疼痛秽臭的，都属于阳明。或者是诸经错杂之邪，与外因为患，都分虚实治疗。肾经寒者，用安肾丸、还少丹，重的用八味丸主治。如齿痛摇动，肢体倦怠，饮食减少不想吃的，是脾胃亏损之症，用安肾丸、补中益气汤并服。如果喜欢寒恶热，是胃血受伤，用清胃汤。如果恶寒喜热，是胃气受伤，用补中益气汤。凡是齿痛遇劳累即发，或午后严重的，口渴面色黑，或遗精的，都是脾胃虚热，补中益气，用六味丸或十全大补汤。如果齿龈肿痛，连及腮颊，这是胃经风热，用犀角升麻汤。如果善饮酒者，齿痛，脸颊肿，这是胃经湿热，用清胃汤加葛根，或解酲汤。海藏说：齿龈臭秽不可近，当作阳明蓄血治，桃仁承气汤为末，蜜丸服用。间有齿缝出血的，我用六味地黄汤加骨碎补，大剂一服即愈。间有不愈的，是肾中火衰也，本方加五味子、肉桂即可。
王节斋说：牙床肿痛，齿痛动摇，或黑烂脱落，世人皆作肾虚治，殊不知这属于阳明湿热症。盖牙齿虽属肾，但生于牙床，上下牙床属阳明大肠与胃，就像树木生于土地一样。肠胃伤于美酒浓味，膏粱甘滑之物，以致湿热上攻，则牙床不清，而为肿为痛，或出血，或生虫，由此牙齿不得安宁，而动摇黑烂脱落。治疗宜泻阳明之湿热，则牙床清宁而齿固矣。
张介宾说：口苦口酸等症状，《原病式》都指为热，不知道口苦未必因心火，口淡未必尽胃热。凡思虑、劳倦、色欲，多有口苦舌燥，饮食无味。或因心脾虚，肝胆邪溢而为苦；或因肝肾虚，真阴不足而为燥。凡口淡，或在大劳、大汗、大泄、大病后，多有此症。若无火症火脉，都是劳伤之症。
凡口渴与口干不同：渴因火燥有余，多实热，干因津液不足，为阴虚。然而渴有实热之渴，亡阴之渴。凡大泻、大汗、大劳、大病、新产、痈疽后，悉由亡阴水亏所致。
舌苔黑，有虚火、实火之别：实热之黑，必兼红紫干渴或多芒刺；若沉黑少红，而带润滑，非实证也。六脉细弱，形困气倦，最为虚候，必寒水乘心，火不归原之病，治标即死。
鼻塞由风寒者，多喷嚏，多在太阳经，宜辛散。火炎上焦，出自心肺，用黄芩知母汤。火甚多出阳明，微兼头痛，用竹叶石膏汤。大约常塞者多火，暴塞者多风，以此辨之。
鼻渊由太阳督脉之火上连于脑，多由湿热上熏，津汁溶溢而下，有作臭者，古方用辛散，不如但清阴火，而兼以滋阴，为高者抑之之法。若流渗既久，液道不能扃固，故新病多因于热。漏泄既多，伤其髓海，则气虚于上，多见头脑隐痛，及眩运不宁等症，此非补阳不可，宜十全大补汤。
阳明热壅牙痛，用清胃散。肾阴虚，为热渴，用玉女煎。外治，辛温可散热，用三香散、赴筵散。虫牙蛀空痛，用巴豆丸。牙缝出血，胃火所致；亦有阴虚于下，格阳于上，六脉微细，血出不止，手足厥冷，速宜镇阴煎。肾虚症当辨寒热，热证六味丸，寒证八味丸，通加骨碎补丸，妙。若齿牙浮动脱落，牙缝出血，而口不臭，亦无痛，肾中阳虚，用安肾丸。走马牙疳，腐烂脱落，速内泻阳明之火，外宜冰白散、三仙散，或用干枣烧存性，同枯矾敷之效。
凡是牙齿脆、摇动疏豁，或突而不实，宜补肾，若因劳酒色，齿有浮突之意，轻轻咬实，渐咬渐齐。或日行二三次，而根自固。于小解时，先咬定牙根，则肾气可摄。不仅固精，亦能坚齿。又夜晚漱洗，或饭后必漱齿，至老坚白不衰。
Zhang Sanxi said: The *Neijing* states that the center corresponds to yellow, internally connects with the Spleen, and opens into the mouth.
Furthermore, the mouth belongs to the Upper Jiao (Upper Burner) of the Heart and Lung; when these organs are diseased, the mouth is also affected. If there is pathogenic heat in the Stomach, it flares upward causing pain and discomfort. Investigating the origin, emotional disturbances (Seven Emotions), and excessive indulgence in the Five Flavors can all lead to this condition.
Therefore, Liver Heat causes a sour taste in the mouth, Heart Heat causes a sweet taste, Lung Heat causes a pungent/spicy taste, and Kidney Heat causes a salty taste. A bland taste indicates Stomach Heat. There are cases where indecisive planning causes Liver heat to transfer to the Gallbladder, resulting in a bitter taste; or where weak Spleen and Stomach Qi allows Wood to overact on Earth, causing acidity; or where Bladder heat transfers to the Small Intestine, obstructing the diaphragm and intestines, rising to cause oral ulcers. Thus, mouth sores and broken tongue are due to fire flaring upward, not solely attributed to the Spleen. Danxi further stated: Excessive labor leads to deficiency fire flaring upward; if cooling medicines fail, it belongs to Middle Qi deficiency. Deficiency fire flares upward without restraint, treated with Pao Jiang (Processed Ginger) and Lizhong Tang (Regulate the Middle Decoction). The principle is clear.
Zhao Yangkui said: Mouth sores involve excess heat in the Upper Jiao, deficiency cold in the Middle Jiao, and yin fire in the Lower Jiao, with transmission through various meridians, requiring differentiated treatment. Fever with thirst for cold drinks indicates excess heat; mild cases use Buzhong Yiqi Tang (Tonify the Middle and Augment the Qi Decoction), severe cases use Liu Junzi Tang (Six Gentlemen Decoction). Poor appetite and loose stools indicate Middle Qi deficiency, treated with Renshen Lizhong Tang (Ginseng Regulate the Middle Decoction). Cold extremities and abdominal pain indicate Middle Qi deficiency-cold, treated with Fuzi Lizhong Tang (Aconite Regulate the Middle Decoction). Afternoon fever and internal heat indicate Blood deficiency, treated with Bawu Tang (Eight Substance Decoction) plus Mudanpi (Moutan Cortex), Wuweizi (Schisandra Fruit), and Maidong (Ophiopogon Tuber). Fever with thirst, expectoration, and frequent urination indicate Kidney Water deficiency, treated with Bawei Wan (Eight-Ingredient Pill). Fever at dusk or originating from the lower abdomen indicates Yin deficiency, treated with Siwu Tang (Four Substance Decoction) plus Renshen (Ginseng), Baizhu (Atractylodes Rhizome), Wuweizi, and Maidong; if ineffective, use Jiaban Bawei Wan (Modified Eight-Ingredient Pill). If heat comes and goes, appearing by day and hiding by night, moving irregularly or without fixed location, or arising from the Lungs, it is rootless fire, treated with the aforementioned pills, or Shiquan Dabu Tang (Complete Great Tonifying Decoction) plus Maidong and Wuweizi, along with Fuzi (Aconite Root) powder mixed with saliva applied to Yongquan (KI 1). Using cold/cooling medicines indiscriminately causes significant harm.
Wang Jiezhai said: Nasal congestion impairing smell, occurring mostly in cold months or upon slight exposure to wind-cold, often recurring, is commonly mistaken as Lung Cold by laypeople, who use acrid-warm exterior-releasing and unblocking drugs. However, this is actually latent fire in the Lung Meridian; when fire is severely constrained, it prefers warmth and dislikes cold. Hence, congestion occurs in cold weather and upon exposure. Treatment focuses on clearing Lung heat and descending fire, assisted by agents that promote ventilation. For chronic nasal congestion, review the patient's constitution and treat as Lung Heat, using Jin Qing Xie Huo Xiao Tan (Clear Metal, Drain Fire, Resolve Phlegm) methods, via lozenges or gentle powder administration; long-term use is effective. For acute onset without prior history, treat as Wind-Cold. Red nose results from blood-heat steaming the Lungs after alcohol consumption, compounded by external wind-cold causing blood stasis; redness without alcohol is due to Lung Wind and blood-heat. Nasal sores, polyps, and abscesses are caused by Lung Heat, varying in depth and pathology. Chronic cases may form fleshy growths blocking the nose. Danxi stated: Food stagnation and hot phlegm in the Stomach flow downward, condensing turbidity to form growths. Nasal polyps require resolving stagnation and generating new tissue, treated with Siwu Tang plus Huangqin (Scutellaria Root), Honghua (Safflower), Fuling (Poria), Chenpi (Tangerine Peel), Gancao (Licorice Root), and Shengjiang (Fresh Ginger), mixed with Wulingzhi (Trogopterus Dung) powder; add Huangqi (Astragalus Root) if Qi is weak.
Teeth belong to the Kidney; upper and lower gums belong to the Yangming Meridians. The upper gum relates to the Stomach Yangming, the lower gum to the Large Intestine Yangming. Teeth that are loose, fragile, painful or painless, bleeding or non-bleeding, resembling impending loss, belong to the Kidney. Gums that are swollen but firm, ulcerated, painful, and foul-smelling belong to Yangming. Mixed pathogenic factors from various meridians combined with external causes should be treated by distinguishing deficiency and excess. Kidney Meridian cold is treated with Anshen Wan (Calming the Kidney Pill) or Huanshao Dan (Restore Youth Elixir); severe cases use Bawei Wan (Eight-Ingredient Pill). Toothache with loosening, limb fatigue, and poor appetite indicate Spleen/Stomach damage, treated with Anshen Wan and Buzhong Yiqi Tang together. Preference for cold and aversion to heat indicates Stomach Blood injury, treated with Qingwei Tang (Clear the Stomach Decoction). Aversion to cold and preference for heat indicates Stomach Qi injury, treated with Buzhong Yiqi Tang. Toothache triggered by exertion or worse in the afternoon, accompanied by thirst, dark complexion, or spermatorrhea, indicates Spleen/Stomach deficiency-heat, treated with Buzhong Yiqi Tang, Liuwang Wan (Six-Ingredient Pill), or Shiquan Dabu Tang. Swollen/painful gums extending to cheeks indicate Stomach Meridian wind-heat, treated with Xijiao Shengma Tang (Rhinoceros Horn and Cimicifuga Decoction). In drinkers, toothache and cheek swelling indicate Stomach Meridian damp-heat, treated with Qingwei Tang plus Gegen (Pueraria Root) or Jiecheng Tang (Resolve Intoxication Decoction). Haizang stated: Foul-smelling gums suggest Yangming blood accumulation, treated with Taoren Chengqi Tang (Peach Kernel and Rheum Decoction) powder in honey pills. Occasional interdental bleeding is treated with Liuwei Dihuang Tang (Six-Ingredient Rehmannia Pill) plus Gusuibu (Drynaria Rhizome) in large doses for quick recovery. If ineffective, it indicates declining Kidney fire, adding Wuweizi and Rougui (Cinnamon Bark) to the base formula.
Wang Jiezhai said: Swollen/painful gums, loose teeth, black decay, and shedding are often mistakenly treated as Kidney deficiency. In fact, they belong to Yangming damp-heat. Although teeth belong to the Kidney, they grow in the gums, which belong to the Yangming Large Intestine and Stomach, like trees growing in soil. Damage to the intestines/stomach from rich foods and alcohol causes damp-heat to attack upward, clouding the gums, leading to swelling, pain, bleeding, or worms, causing teeth to loosen, decay, and fall. Treatment should drain Yangming damp-heat to clear the gums and stabilize the teeth.
Zhang Jiebin said: Symptoms like bitter or sour taste in the mouth are labeled as heat in *Yuanbing Shi*, but bitter taste does not necessarily stem from Heart Fire, nor does bland taste solely from Stomach Heat. Mental strain, fatigue, and sexual excess often cause bitter/dry mouth and loss of taste. Bitterness may arise from Heart/Spleen deficiency allowing Liver/Gallbladder evil to overflow; dryness from Liver/Kidney deficiency and insufficient True Yin. Bland taste often follows severe sweating, diarrhea, or illness. Without heat signs/pulses, these are exhaustion injuries.
Thirst differs from dry mouth: Thirst arises from excess fire-dryness, usually excess heat; dryness arises from insufficient body fluids, indicating Yin deficiency. Thirst includes excess heat-thirst and fluid-loss-thirst. Severe diarrhea, sweating, labor, illness, postpartum, or carbuncles result from fluid loss and water deficiency.
Black tongue coating distinguishes deficiency vs. excess fire: Excess heat blackness accompanies red/purple color, dryness, thirst, or prickles. Deep black with little redness and moisture indicates non-excess. Fine/weak pulses with physical fatigue indicate severe deficiency, likely Cold Water attacking the Heart and Fire failing to return to its source; treating symptoms only leads to death.
Nasal congestion from wind-cold involves sneezing, often in the Taiyang meridian, treated with acrid dispersants. Fire flaring to the Upper Jiao from Heart/Lung uses Huangqin Zhimu Tang (Scutellaria and Anemarrhena Decoction). Severe fire affecting Yangming with mild headache uses Zhuye Shigao Tang (Bamboo Leaf and Gypsum Decoction). Generally, chronic congestion implies fire, sudden congestion implies wind.
Bi Yuan (nasal sinusitis) involves fire from Taiyang/Du Mai connecting to the brain, often damp-heat steaming upward, causing watery discharge, sometimes foul. Ancient formulas used acrid dispersants, but clearing yin fire while nourishing Yin is superior (suppressing what is high). Chronic leakage damages Marrow Sea, causing Upper Qi deficiency, hidden head pain, and dizziness, requiring Yang tonification with Shiquan Dabu Tang.
Yangming heat obstruction toothache uses Qingwei San (Clear the Stomach Powder). Kidney Yin deficiency with heat/thirst uses Yuni Jian (Jade Woman Decoction). External treatments for heat dispersion include Sanxiang San and Fuyan San. Worm-caused hollow toothache uses Badou Wan (Croton Seed Pill). Interdental bleeding from Stomach fire; or lower Yin deficiency with floating Yang above, fine pulses, continuous bleeding, and cold limbs requires Zhenyin Jian (Settle Yin Decoction). Differentiate Kidney deficiency cold/heat: Heat uses Liuwang Wan, Cold uses Bawei Wan, both adding Gusuibu Pill is effective. Loose/shedding teeth with bleeding but no odor/pain indicate Kidney Yang deficiency, treated with Anshen Wan. Gangrenous gingivitis with rotting/shedding requires internal draining of Yangming fire and external application of Bingbai San, Sanxian San, or burnt dried jujube with Mingfan (Alum).
For brittle, loose, or protruding teeth, tonify the Kidney. If due to labor/alcohol/sex, gently bite down firmly, gradually aligning them. Doing this twice daily strengthens roots. Biting firmly during urination captures Kidney Qi, stabilizing essence and teeth. Nightly rinsing or post-meal brushing maintains white, strong teeth until old age.