Dear Doctor: Our daughter is only 4 years old, and she has had her first cavity already. What can we do to make sure that things go better at her next visit to the dentist, and for her new baby brother?

Dear Reader: Tooth decay is common in young children. Their small mouths can make thorough brushing a challenge, and a wriggling and impatient child only adds to the level of difficulty. In fact, studies show that one-fourth of all children have had at least one cavity by the time they turn 4. Fortunately, with consistent dental hygiene, good diet and regular visits to the dentist, you can prevent tooth decay.

Our mouths can play host to hundreds of different types of bacteria, many of them benign, and some even useful. But among their number is a bacterium known as streptococcus mutans, a sugar-loving organism that is responsible for the formation of cavities. Every time we eat, this bacterium gets a meal as well. And as it devours the sugars that linger in our mouths, it produces an acidic byproduct that gradually erodes the tooth’s enamel coating. That’s why brushing and flossing, as well as a diet that limits sugar, are crucial to good dental health. Fortunately, with a few simple steps that you follow every day, you can significantly reduce your child’s risk of developing more cavities.

Even before an infant’s first tooth emerges, you should gently wipe their gums and mouth with a clean, damp cloth after feedings. Their first tooth should be greeted with a soft infant toothbrush that you use for a gentle cleansing after each meal. Brushing with plain water is fine. If you do decide to use toothpaste at this point, make sure it’s a tiny amount, about the size of a grain of rice. As soon as your child has two teeth that touch each other, it’s time to begin flossing. Again, it’s important for you to be very gentle so as not to cause discomfort, pain or bleeding.

Children 3 and older should brush twice a day and continue flossing once a day. Young children are often not coordinated enough, or they lack the attention span, to do a thorough job. If that’s the case with your daughter, continue to brush her teeth for her until you’re sure she’s up to the task. Most kids need help brushing, or at least close supervision, until they’re 7 or 8.

Sugar increases the risk of developing cavities, so diet is also important. Limit sweets, sugary drinks and snacks between meals. And when kids do indulge, get them into the habit of brushing their teeth immediately afterward. All of this will be easier if you set a good example yourself. Be sure your kids see you brushing your teeth after meals, just as you’re asking them to. Ditto for daily flossing.

And don’t forget about the dentist, who will be an important lifelong ally in maintaining good oral health. The American Academy of Pediatrics recommends that kids see a pediatric dentist within six months after their first tooth appears, or by 12 months of age.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I'm 30 years old, and I have a lump in my breast, which imaging tests suggest is a fibroadenoma. I'm getting married in six months, and I am leaning toward having a biopsy so I won’t worry during my wedding and honeymoon. With the COVID-19 pandemic, is it selfish of me to have the biopsy right now?

Dear Reader: It’s understandable that, even with reassuring results from a mammogram and an ultrasound, you want a definitive diagnosis. As you mentioned in your letter, the only way to achieve that is with a biopsy. However, due to the pandemic, many hospitals have been forced to shift their attention and resources to dealing with COVID-19 patients, and some have put elective surgeries and routine medical care on hold. This means that decisions that in normal times would have been fairly straightforward have now become complex issues.

Let’s start with what we do know. Your radiologist has reported that the imaging tests you’ve undergone suggest the mass in your breast is a fibroadenoma, which is a benign tumor. It’s made up of both connective and glandular tissue, and it typically feels hard and smooth to the touch. Fibroadenomas are the most common type of noncancerous growth in young women between the ages of 15 and 35. Some are so small that they can only be seen in a scan, while larger ones are discovered through touch, as during a monthly breast self-exam. No matter the size, in most cases fibroadenomas don’t play a role in risk for breast cancer.

The good news is that imaging techniques are quite good at differentiating between benign masses, such as fibroadenomas and cysts, and those that are malignant. When a benign growth is discovered via imaging, it is often recommended that a follow-up scan be performed within six months. If the results of the subsequent imaging tests raise a red flag, then the next step is a biopsy. This is a surgical procedure in which a small sample is removed from the suspicious tissue and sent to a pathology lab to be looked at under a microscope. It’s only when the tissue is examined at the cellular level that a pathologist can state conclusively if the mass is benign or malignant.

A woman’s age adds another layer to the decision-making process here. When a woman is in her teens and 20s, benign causes for a breast mass are considered to be more likely. But that changes for women in their 30s, particularly now, as we are seeing more young women diagnosed with breast cancer. In your case, it would be wise to seek guidance from both the radiologist who performed and interpreted your scans and your family doctor. This type of biopsy is usually an outpatient procedure that can be performed in a surgical center rather than in a hospital operating room. Wherever you go, check that you are comfortable with the safety protocols that are in place. If your particular region is not hard-hit by the COVID-19 pandemic, and if your medical team agrees that a biopsy is a better choice for you than watchful waiting, there’s nothing selfish about moving forward.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I never had hip problems, but after weeks of quarantine, the outsides of my hips ache and even wake me up when I am asleep. My doctor says it’s bursitis, but I thought that’s from when you exercise too much. I’ve hardly even been outside. How did this happen?

Dear Reader: Bursitis is the name of a condition that occurs when the small, fluid-filled sacs that sit near joints throughout the body become inflamed. Known as bursae (or a bursa, when you’re talking about just one), they act as cushions that ease friction between the bone and other moving parts within the joint, such as tendons and muscles. When a bursa becomes inflamed or irritated, it fills with fluid. The swelling leads to more irritation, as well as pain and a limited range of motion.

Although bursae are present in joints throughout the body, bursitis is most common around the major joints. That includes the hip joints, as you’ve been experiencing, as well as the knee, shoulder and elbow. And you’re correct that bursitis most often occurs due to overuse, particularly through activities that include repetitive motion. Activities like raking, painting and gardening, and sports like tennis, skiing, running, biking and golf can lead to stress and inflammation. Bursitis also is linked to gout, rheumatoid arthritis and psoriatic arthritis; it can result from physical injury; and it may be triggered by reactions to certain medications.

Interestingly, hip bursitis can arise as the result of inactivity. The hip abductor muscles, which we use to move the leg away from the body and to rotate it within the hip joint, can become weak through lack of use. This results in increased pressure on the bursae. Prolonged sitting and standing can also lead to stress and inflammation.

Symptoms of hip bursitis include tenderness and swelling and the ache that you describe on the outside of the hip. This typically increases when rising from a sitting position, walking up stairs or when lying on one’s side. Any problems you may have with your lower limbs, such as knee or foot pain, can cause you to move in such a way that irritates the hip bursae.

Treatment focuses on the dual goals of reducing inflammation and strengthening the supporting hip muscles. Your doctor may prescribe the use of anti-inflammatory medications, and will likely show you some home-based exercises to increase strength and improve muscle tone in the abductors. Some people find that ice can help to minimize swelling and reduce pain. In some cases, the bursae can become infected, which necessitates the use of oral antibiotics. When more conservative treatment approaches don’t bring relief, injections of a corticosteroid may be recommended.

For people who develop hip bursitis due to repetitive overuse, rest is a crucial part of their recovery. In your case, the challenge will be strengthening the supporting muscles without causing additional irritation and inflammation. Avoid prolonged sitting or standing, follow the exercise guidelines that your doctor gives you, and don’t be tempted to overdo it.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)