A patient must exercise ordinary care and prudence [438]; so that, if one tells the dentist to pull out a tooth, but does not say which one is to go, and the wrong one is taken out, the sufferer has no legal ground of complaint, unless, indeed, it is quite apparent which is the offending member. A patient may have been a little careless and negligent; still, if the dentist has been so very neglectful of his duty that no ordinary care on the part of the patient would have prevented the mistake or injury complained of, the injured party will recover, _i.e._, recover damages for the injury received [439]. The fact that one has taken chloroform will not affect his rights or remedies against the tooth-puller for any mistake or negligence. The maxim _vigilantibus, non somnientibus jura subveniunt_, has no reference to people put to sleep by anæsthetics. In New York, two dentists undertook to extract a tooth from a patient while the latter was under the influence of laughing gas. During the operation the forceps slipped, and part of the tooth went down the patient’s throat, causing coughing and vomiting for four weeks, when—in a fit of coughing—the tooth came up, and relief followed. The patient sued for damages, and when the case came before it, the Court said, “The defendants (the dentists) knew that the plaintiff (the patient) while under the influence of the anæsthetic, had no control of his faculties, that they were powerless to act, and that he was unable to exert the slightest effort to protect himself from any of the probable or possible consequences of the operation which they had undertaken to perform. He was in their |164| charge and under their control to such an extent that they were required to exercise the highest professional skill and diligence to avoid every possible danger; for the law imposes duties upon men according to the circumstances in which they are called to act. In this case, skill and diligence must be considered as indissolubly associated. The professional man, no matter how skilful, who leaves an essential link wanting, or a danger unguarded in the continuous chain of treatment, is guilty of negligence, and if the omission results in injury to the patient, the practitioner is answerable. The quantum of evidence necessary to make out a _primâ facie_ case of negligence is very slight in some cases, while in others a more strict proof is required. Often the injury itself affords sufficient _primâ facie_ evidence of negligence. * * * There was evidence offered by the plaintiff showing, that while the defendant drew the tooth, the forceps slipped. This fact, combined with the unusual circumstance that the tooth went down instead of coming up, was sufficient to carry the case to the jury upon the question of negligence. The trial Judge held that while the affirmative was upon the plaintiff to prove negligence, the fact that the defendants, instead of taking the plaintiff’s tooth out, let it go down his