Xiao Xue (pseudonym)'s dental condition
Xiao Xue (pseudonym) interviewed by media
Xiao Xue (pseudonym) and her attending physician interviewed by media
At age 12, her teeth began decaying—toothpicks would shatter them into powder.
According to Xiaoxue, she experienced normal childhood tooth development—losing baby teeth and gaining permanent teeth—until age 12 when her teeth suddenly deteriorated. "At first, they just turned yellowish-black, then gradually developed small cavities that grew larger. When I inserted a toothpick into a cavity, the tooth crumbled into powder."She explained that initially only one tooth was affected, but the condition gradually spread to all her teeth, causing them to decay and crumble one by one.
"I used to think it was just regular tooth decay, but after visiting the dental hospital for an examination, I learned it wasn't.The doctor said it was likely caused by my parents being closely related." After a thorough diagnosis by Professor Zhou Xianfeng, Director of Guangzhou Straits Dental Center, Xiaoxue's rare condition was confirmed as congenital permanent tooth absence, possibly resulting from consanguineous marriage. Xiaoxue revealed that neither her parents' generation nor her grandparents or maternal grandparents had any dental issues.
For nine years, she could only consume liquids and soft foods, suffering severe nutritional loss.
Xiao Xue's teeth began falling out at age 12, leaving her toothless for nine years. During this time, she survived on noodles, congee, and extremely soft rice. "I could eat a little cabbage—the lower molar could bite it—but without the upper molars, eating was exhausting.Meat must be ground into mince. Most foods need to be chopped extremely finely before I can eat them. Where I have no teeth, I grind food with my gums, which often become inflamed. I buy anti-inflammatory medication myself or eat mung bean porridge to reduce the inflammation."
Regarding Xiaoxue's dietary situation, Professor Zhou Xianfeng stated that even if she manages to consume these foods, her nutritional needs remain unmet."For large, brittle foods, the central incisors and lateral incisors cut them into smaller pieces, which are then crushed by the canines and ground by the molars before swallowing. Fibrous foods like lean meat or sugarcane require tearing by the canine teeth on either side, followed by crushing and grinding by the molars.These dental functions ensure proper digestive processes in the gastrointestinal tract. For patients like Xiaoxue with severe tooth loss, while they can barely swallow food, most items remain inadequately ground. Consequently, normal digestion cannot occur in the stomach and intestines, preventing nutrient absorption," Professor Zhou explained in detail.
With such a poor oral environment, dental implant surgery is necessary to restore missing teeth.
So, how should Xiaoxue's current situation be addressed? Professor Zhou Xianfeng, Director of Guangzhou Straits Dental Center, noted that Xiaoxue's oral condition is extremely poor. She currently has only two or three teeth remaining, and even those are about to decay and fall out. X-rays reveal that her decayed teeth have lost all their roots. In this case, dental implant surgery is the only option for tooth restoration.
"Based on her oral condition, we will implant 14 teeth. Given her youth, we will select the highest-quality Swiss implants. These implants are robust and stable, minimizing potential oral complications. With this dental support, her lips and jawline will significantly improve, avoiding the sunken appearance typical of an 80-year-old woman. This approach restores both dental function and aesthetic appeal.However, due to the prolonged absence of teeth, some gum tissue has begun to recede, making the surgery more challenging," said Professor Zhou Xianfeng.
Marriage between close relatives requires caution, as it can lead to the homozygosity of recessive disease genes.
Marriage between cousins is a relatively common form of consanguineous marriage.Most countries discourage or even prohibit such marriages. This is because offspring from consanguineous unions exhibit higher mortality rates and frequently suffer from dementia, birth defects, and genetic disorders. Since consanguineous couples inherit more identical genes from shared ancestors, harmful recessive genes detrimental to survival are more likely to meet (homozygosity) in offspring, increasing the risk of producing children with poor health outcomes.According to World Health Organization estimates, each individual in a population carries approximately 5 to 6 disease-causing genes for recessive genetic disorders. In random marriages (non-consanguineous unions), since spouses are unrelated, they share few identical genes and carry different recessive disease genes. This makes it less likely for recessive disease genes to become homozygous (resulting in affected individuals).In contrast, consanguineous marriages significantly increase the likelihood that both partners carry the same recessive disease gene. This raises the probability of these genes meeting in offspring, substantially elevating the incidence of genetic disorders in the next generation. Rare dental conditions like Xiao Xue's are highly likely caused by homozygosity for recessive disease genes. Therefore, doctors strongly urge against consanguineous marriages.