Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
Q: Context: Severe generalized spastic movement disorders of various aetiologies often involve the jaw muscles and lead to a spastic trismus with masseter muscle hypertonia. We report a placebo-controlled randomized study on patients with spastic trismus.', 'Eleven patients with masseter hypertonia because of stroke, hypoxic encephalopathy or traumatic brain injury were allocated to either botulinum toxin serotype B (BoNT/B) injections into the masseter muscles or placebo treatment. The dental gap, the amount of saliva, salivation scales, and a clinical goal attainment were evaluated.', 'Three weeks after injection the BoNT/B group showed a significantly increased mouth opening compared with placebo treatment (P < 0.05). In addition to the muscle paralysing effect, a goal attainment scale demonstrated a clinical benefit for the BoNT/B group (P < 0.01).
Answer: Botulinum toxin serotype B injections into the masseter muscles effectively reduce hypertonia and provide for better mouth opening, thereby contributing to a positive and desired clinical goal.
A:
Does botulinum toxin B increase mouth opening in patients with spastic trismus?