Many people are finding that the metal bits used on our horses of the past are just not cutting the mustard so to speak, and interest in the bitless bridle is greater now than ever before. Over the years, one hears countless horror stories of tragic injuries which would be totally avoided had the owner simply had a bitless system in place when the accident occurred, and I suppose as horses become less a commodity and more of a family pet this trend will only continue to follow.
I won't go into the numerous tragedies I have run into over the years, simply the reasons for owning a bitless bridle. For starters, we all have a non horse oriented friend that just wants to try out a trail ride, and most such people are not trained with gentle hands. This can result in sore mouths in the horses you lend, a bitless system will prevent any major pain or damage from occurring while your inexperienced friend rides with you. Another good reason is if you should have a horse with bad or aged teeth. Horse's teeth grow throughout their lives and some develop issues as they get older. Horses that took a metal bit fine early in life may not appreciate on later on as they age and such will greatly appreciate the gentle touch of the bitless bridle. I often hear about people using bosels, but in my opinion the bitless system is kinder to the delicate skin of the nasal passages, and many bosels (most especially the cheaper ones) will take the skin right off a horse's nose if they wear it long enough. Arabian horses have particularly thin skin and are exceptionally prone to this.
Using a bitless bridle may not be for just everyone, but one can never tell if they are about to have an accident that will take permanent toll on the horse that you call family, so consider using one in most cases if you can. They are a more modern, and a much gentler idea than just cramming a piece of cold steel into your horse's mouth. Bitless bridles are far less likely to cause pain and injury, and offer better release than does a mechanical hackamore. There are several varieties available, but I think the best ones are affordable and simple in design.