In order for there to be suffering, as I see it, you need two things, the physical component which creates the context for the suffering to occur (a sensory organ which experiences suffering and an object to suffer over) and a mental component of craving.
Dukkha ("suffering") is distinguished from pain, which can also be a kind of neutral feeling. What we call "physical pain," is defined by not simply its physical, but the aversion to pain. A Buddha, from what I remember, is said to feel physical pain but does not experience it mentally. Recognizing the physical interaction, but not labeling it, "I" or "mine", the pain has no existential meaning for him; in a sense, it does not exist. An analogy might be Arnold Schwarzanegger as the Terminator -- in one scene of the movie, when asked if he feels pain, he says coldly that he detects injury, but does not experience the emotional response humans call pain. Is this similar to the Buddha's own experience of pain?
Anyway, Theravada Buddhism does not seem particularly concerned with the physical component of suffering, except to the extent that the basic nature of reality constrains behavior (so, in order for behavior to be skillful, it must conform to the laws of reality, but Theravadins do not bother considering it fundamental to know these laws, in biology, physics, etc.). "Medicine" is something even forbidden for monks to practice (although perhaps this only applies to the superstitious "folk medicine" practices, like Ayurveda).
Now, a possible justification for this is that it is, in some way, easier to end all suffering through control of the mental component than manipulating the physical component. A Buddhist story I've heard on this point is about a king or queen who wanted to cover the world in leather, but their advisor recommended they just wear leather on their feet (hence the invention of shoes). The point is that it's easier to care after the point of contact -- your feet with the ground, your mind with your life -- than to try to control the whole circumstance -- the entire ground, all of reality.
But still, this doesn't negate the fact that scientific progress has an impact on suffering, because it removes various contexts in which craving might occur. I have heard descriptions of the lives of Egyptian laborers or those who built the Great Wall of China, or of the tribes in Africa today, and these kinds of primitive societies do not seem like they would make a person as happy as modern, prosperous nations. This coheres to what I've heard of psychology's view on the relationship between happiness and wealth: although extravagant wealth has no impact on happiness (the existence of luxuries does not remove craving, so no suffering reduced), but a basic subsistence, which could even be measured in dollars, does contribute to happiness. I think it's pretty naive, for instance, to actually believe the myth that Tibetans or Bhutanese can be dirt-poor, face political oppression, famine, disease, etc., and yet still be happier than average.
I don't doubt that it is possible for an individual to be happy despite circumstance, but collectively, people are always carried by circumstance, either they're lucky or victims of circumstance. The kind of mental purity that comes from Dhamma practice is unconditioned, such that even superficially practicing Buddhism does not ensure happiness.
Individually, a person born in ancient times who was reborn in modern times may have been about as happy, or more or less, depending on how much desire and aversion they felt (a basic notion of existentialism: you can get used to anything. A person born in medieval times could be just as happy as a person today, because they weren't aware of the possibilities of what we have today, so there was no such thing for them to crave and few people obsessively crave over fantasies, but instead, they crave things which are more immediate -- a medieval person would crave something close to his time, which he could see and touch.). However, collectively it's a different matter. Nobody, as I see it, can deny that advancements in medicine, consumer technology (refrigerators, air conditioning, food canning, etc.), and economic advances has not reduced aggregate or collective suffering. Although a person in medieval times did not crave these things, if we could give them these things, it would make life better for them and possibly give them an opportunity for happiness (if they exist as slave laborers, etc.).
So, is science and the physical context in which suffering occurs not also important? If a scientist finds a cure for a major disease, does this not alleviate suffering at least as much as a Dhamma talk? Shouldn't monks contribute to science, too, because of this?