Comparison Panasonic EW-1211 vs Panasonic EW-DJ40

The number of working nozzles that are standardly supplied with the device. Nowadays, options are quite common with both one and two or three nozzles in the kit; and in the most extensive sets, this number can be four or five or even more.

In many sets, several nozzles may have different purposes. For instance, an irrigator, in addition to its standard nozzle, might include orthodontic and periodontal nozzles. However, it's important to note that models with the same number of accessories in the kit can have different specific specializations. So, when making a choice, it's wise to consider not just the quantity but also the types of nozzles available. Additionally, there's an option where several identical interchangeable heads come with one handle. This configuration is particularly common in toothbrushes. It enables multiple individuals, such as family members, to use a single device, and such a set is usually more cost-effective than purchasing individual toothbrushes for each person.

The pressure of the water supplied by the irrigator (see "Type") to the operating nozzle. Usually, this pressure can be adjusted within a certain range, since different situations and purposes require different processing intensity. The wider this range, the more versatile the device.

The lower limit of the pressure range in modern irrigators is around 30 kPa; similar values are set for procedures for sensitive teeth, for certain gum diseases and in other cases where the most gentle treatment is required. 400 – 500 kPa is considered an average level, and 600 – 650 kPa is considered high, such indicators allow for deep cleaning (see "Functions"). And higher values are rare, and they are used mainly when cleaning the tongue. However, it is best to consult with a dentist before purchasing an irrigator and choose a model for working pressure based on the recommendations received.

The volume of the reservoir for water (or treatment solution) provided in the design of the irrigator or flossing system (see "Type").

In general, the larger the tank, the less often you have to refill the device, but the larger, heavier and more expensive the whole structure is. Thus, in portable format irrigators, where the water tank is built right into the handle, the capacity is small — even in the largest models it usually does not exceed 400 ml, a larger tank would noticeably complicate use. However, even the smallest volumes in such cases are usually enough for at least one standard procedure. But stationary models, consisting of a handle and a separate main unit, can hold very significant volumes of water — up to 1.5 L or even more.

Additional items supplied with the device (in addition to the base and attachment set).

The most popular types of such items nowadays are charging stand, accessory stand, UV sanitizer and case ; Here is a more detailed description of each option:

— Charging stand. A battery charging device designed as a stand serves the dual purpose of recharging the battery and offering added convenience for storing the device. It's worth noting that this function can apply to dental centers, even if they primarily operate on mains power (as indicated in the "Type of power" section). In such cases, the toothbrush included with the dental center typically runs on batteries, and the charging stand is typically integrated directly into the main unit of the dental center for ease of use.

— Stand for accessories. A device designed to hold various accessories, primarily interchangeable nozzles, can come in different designs. For example, in toothbrushes and portable irrigators, this device is often integrated into a charging stand, which includes both a charging socket and open compartments for accessories. In irrigators and fixed-layout dental centers, these compartments are usually built into the main unit or the lid of the water tank. In this case, the compartments are typically covered with lids for hygiene reasons, making it...a more hygienic option. Regardless of the design, having a dedicated stand for accessories enhances the convenience of storing them.

— UV sanitizer. A device that uses ultraviolet (UV) radiation for disinfecting the device, particularly replaceable nozzles, is typically designed as a distinctive container. In some models, this container also serves as a cover or case. The disinfection process effectively eliminates the majority of pathogenic bacteria and viruses, all without the need for additional chemicals and ensuring safety as the radiation remains confined within the container. However, it's important to note that UV disinfection is not effective against regular dirt and debris, so having this function doesn't eliminate the need to clean the nozzle through washing.

— Case / cover. The device comes with a storage and carrying container, which can be either a hard case or a soft cover. Hard cases offer better protection, while soft covers are more compact and can be rolled up when not in use. Regardless, both of these accessories are highly convenient for storage and transportation. They safeguard the contents from dirt and damage, and in many cases, provide space to store additional accessories, reducing the risk of losing them. While you could use makeshift packaging for the same purpose, the provided container is typically more practical.

This refers to the maximum duration a device can run continuously when powered by a fully charged battery or fresh batteries. It's worth noting that this metric may also apply to models designed for mains power, such as flossing systems that include rechargeable toothbrushes, in which case we're referring to the battery life of these toothbrushes.

It's important to note that device specifications typically indicate the maximum runtime under ideal conditions, often in the most energy-efficient mode of operation (and for models with replaceable batteries, using high-quality batteries). The actual battery life can vary depending on specific usage conditions. However, this parameter still serves as a valuable basis for comparing different models. Generally, differences in the claimed operating time correspond proportionally to the real differences in battery life. For example, if one toothbrush has a stated operating time of 20 minutes and another boasts 40 minutes, in practice, their battery life (under similar conditions) will likely differ by approximately two times.

It's important to consider that, for toothbrushes, this parameter can help estimate the number of brushing sessions you can expect on a single charge. Typically, the recommended daily brushing duration is 2 minutes. So, if a toothbrush has an operating time of 30 minutes, it's sufficient for approximately 15 cleaning sessions (or more realistically, around 14 or 13).

The time required to charge the battery from zero to 100% in a device with the appropriate power type (see above). This parameter can vary from 1 – 3 hours in relatively simple and low-power devices to a day in advanced models with capacious batteries. At the same time, the longer the maximum operating time on a charge (see above), the longer, usually, the time required for charging, although there is no hard dependence here.

In general, having fast charging capabilities improves the convenience of a device by reducing interruptions in its operation. However, there is a trade-off to consider: fast charging often means either a smaller battery capacity or a higher price due to the use of specialized technologies to speed up the charging process. When evaluating this parameter, it's essential to think about how you intend to use the device. For instance, if a toothbrush or irrigator is solely used at home by one person and comes with a charging stand, fast charging may not be a critical factor. The device remains consistently charged as it's constantly on the charger, and its battery doesn't deplete significantly during one use. The time between sessions, usually around 8 to 12 hours, is more than enough to maintain a charged battery, even for devices with slower charging. However, if you plan to use the device while traveling, where access to power outlets is sporadic, it's preferable to have minima...l charging time to ensure you can recharge quickly during your trips.

General dimensions of the device. Most manufacturers report this data only for stationary devices — irrigators of the appropriate variety and dental centers (see "Type") — because it is believed that toothbrushes (even with stands) are not so large as to be inconvenient, and not so varied in size, to pay attention to this difference.

Note that the dimensions are usually given only for the main unit, without taking into account the tools installed on it; however, the size of these instruments, again, it is not large enough to cause serious inconvenience.

The total weight of the device is an important consideration. In the case of stationary irrigators and dental centers (as mentioned in the "Type" section), weight isn't a significant factor since the main unit is placed on a stand or wall, and you don't have to hold it. In fact, for some of these models, weight may not even be specified. However, when it comes to toothbrushes or portable irrigators, the device's weight becomes a crucial factor. A heavy device can strain your hand and make it challenging to use during teeth brushing or other procedures. It's generally recommended that the weight of a portable device should not exceed 200 g, and lighter is often better. It's worth noting that in models that come with stands (as discussed earlier), the total weight is typically provided, accounting for both the main unit and the stand. The weight of the main unit alone is usually around 1.5 to 2 times less than the total weight.