Orthodontic and standard (flattened) pacifier shapes are the best options for your baby’s oral development. Compared to round, bulbous pacifiers, these designs reduce pressure on the palate by over 90% and cut potential tooth displacement by 75 to 79%. The classic cherry-shaped pacifier, while popular, puts significantly more force on your baby’s mouth and carries a higher risk of dental problems with prolonged use.
The Three Main Pacifier Shapes
Pacifiers come in three basic nipple designs, and the differences matter more than most parents realize.
Orthodontic pacifiers have a flattened, slightly angled nipple with a convex curve designed to follow the shape of your baby’s palate. They’re the most common type marketed as “dental-friendly.”
Standard (symmetrical) pacifiers have a flattened, oval nipple that looks the same on both sides. Because there’s no “right side up,” these work well for babies who constantly flip their pacifier around in their mouth.
Conventional (cherry or bulbous) pacifiers have a round, ball-shaped nipple that’s noticeably thicker than the other two types. These are the traditional shape many people picture when they think of a pacifier.
Why Shape Affects Your Baby’s Mouth
A pacifier sits against the roof of your baby’s mouth for hours each day, and the shape of that nipple determines how much force gets applied to the palate, gums, and developing teeth. A computational study published in Clinical Oral Investigations compared all three designs and found striking differences. Orthodontic pacifiers reduced the volume of high-stress areas on the palate by 95.7% compared to conventional round pacifiers. Standard flattened pacifiers weren’t far behind, with a 93.95% reduction.
That pressure matters because a baby’s palate is soft and actively growing. Constant force in the wrong spots can deepen the palate, push teeth out of alignment, and narrow the dental arch. The conventional cherry-shaped pacifier, being thicker and rounder, concentrates force on a smaller area of the palate and pushes more aggressively against the front teeth. The study found it caused 77 to 79% more tooth displacement than the orthodontic design.
Open Bite and Crossbite Risks
The two dental problems most strongly linked to pacifier use are anterior open bite (where the front teeth don’t meet when the mouth closes) and posterior crossbite (where the upper back teeth sit inside the lower ones instead of outside). A systematic review in Progress in Orthodontics found moderate evidence connecting pacifier use to both conditions.
The shape you choose changes that risk substantially. In one study comparing orthodontic and conventional pacifiers, 44.3% of open bite cases occurred in the orthodontic group versus 55.7% in the conventional group. A separate randomized controlled trial found that pacifiers with a thin neck, the narrow connection between the nipple and the shield, significantly reduced open bite and excess overjet. That thin neck is key: it minimizes interference with how the teeth come together, giving the jaw more room to close naturally.
What the Nipple Shape Does to the Tongue
Different shapes encourage different tongue positions, and this matters both for feeding development and for long-term oral health.
Long, round pacifiers encourage tongue cupping, where the tongue wraps around the nipple and actively creates suction. This mimics breastfeeding mechanics, which makes these shapes useful when a baby is still learning to latch or transitioning between breast and bottle. If you’re working with a lactation consultant on feeding skills, this type may be recommended during awake practice sessions.
Flattened pacifiers do something different. Instead of prompting active suction, they gently guide the tongue upward toward the roof of the mouth. This is the tongue’s natural resting position, and it’s the healthier posture during sleep and passive soothing. For this reason, lactation professionals often suggest using a flattened shape for naps and overnight, even if a rounder shape is used during feeding practice. Bulbous cherry-shaped pacifiers don’t effectively support either tongue position and are generally the least recommended by feeding specialists.
The Thin-Neck Feature
Beyond the nipple shape itself, pay attention to the neck of the pacifier, the narrow section connecting the bulb to the shield. A thinner neck reduces interaction with the bite, meaning less pressure on the gums and emerging teeth. Physiological pacifiers, which aim to mimic the shape of a mother’s nipple during feeding, specifically use a flattened, thin-necked design. The more horizontal, elongated profile distributes force more evenly across the teeth, gums, and jaw rather than concentrating it in one spot.
When choosing between two otherwise similar pacifiers, pick the one with the thinner, narrower neck.
Getting the Size Right
Shape isn’t the only variable. A pacifier that’s too small for your baby’s mouth can contribute to palatal collapse and improper jaw development, while one that’s too large creates unnecessary pressure. Pacifier bulbs range from 12.5 mm to 25.0 mm across brands, but many companies use age-based sizing (0 to 6 months, 6 to 18 months) that doesn’t account for the wide variation in babies’ facial dimensions.
Age-based charts are a reasonable starting point, but they’re not precise. Babies of the same age can have meaningfully different mouth sizes depending on their weight, ethnicity, and individual growth patterns. Some companies now offer biometric sizing tools, including apps that use a photo of your baby’s face to recommend a better fit. If your baby consistently gags on a pacifier or can’t keep it in their mouth, the size is likely wrong regardless of what the package says.
Silicone vs. Latex: How Material Affects Shape
The two main pacifier materials hold their shape differently over time. Silicone is firmer, odorless, and taste-neutral. It doesn’t age, tolerates high-temperature sterilization, and maintains its original form through months of use. Latex (natural rubber) is softer and more flexible, which some babies prefer. But that softness comes with a tradeoff: the strong suction of a baby’s mouth can stretch and deform a latex nipple over time, meaning it may lose its orthodontic shape if you don’t replace it frequently.
Latex also breaks down faster from UV light, saliva, and heat. If you choose a latex pacifier for its softer feel, inspect it regularly for changes in shape, stickiness, or discoloration and replace it as soon as you notice wear. Silicone is the more reliable choice if maintaining the intended nipple shape over time is a priority.
Safety Basics That Apply to Every Shape
Regardless of nipple design, the Consumer Product Safety Commission requires that pacifiers pass structural integrity tests to prevent choking hazards. Look for one-piece construction, meaning the nipple and shield are molded together rather than assembled from separate parts. The shield should be at least 1.5 inches across (so the entire pacifier can’t fit into your baby’s mouth) and made of firm plastic with ventilation holes. Never use a bottle nipple as a substitute pacifier: under strong suction, a bottle nipple can separate from its ring and block an infant’s airway.
The American Academy of Pediatrics keeps its shape recommendation simple: try different kinds until you find one your baby accepts. Babies have strong preferences, and even the most orthodontically ideal pacifier is useless if your child spits it out. Within the range of flattened and orthodontic options, let your baby’s preference guide the final choice.