Firstly saw dust in the center could be any thing, can you see flight holes with the dust as this is where they have left in order to lay eggs and then die. holes in the bark , could be bark sap beetle wont, harm timbers in flat. Very small flight holes could be powder post beetle and would not spread to flat. Furniture beetle (Anobium Punctatum) however started in the forest in dead timbers and spread into homes in the early 1900's when plywood was first manufactured, - the glue used in the veneers of early plywood was high protein animal glue, which they (the woodworm) really loved. Since then they have spread into all house timbers including oak if it is a little soft (damp). Other timbers including furniture needn't be damp as they really go for the cellulose in the sapwood. They can stay in the timber for 3 to 4 years and only make the flight hole (commonly seen but they are already in there) when they change into a beetle and exit the wood, they generally leave between May and the end of July, but central heating in homes can alter this. Any woodworm treatment fluid will only kill the woodworm where the fluid has penetrated, and will not kill the remainder lying deeper in the timbers until they go to leave the wood, and they eat the treated timber over the next 3-4 years on leaving.
Of course if you treat any timber and then sand or cut any of the wood in order to make your coffee table, you will have removed the treated wood, so therefore if it is indeed woodworm the coffee table should really be made outside, and once completed prior to applying any sealers of any kind it should liberally treated with all over with commercial woodworm fluid following the manufacturers instructions. Also remember these chemicals are highly toxic and should only be used in ventilated spaces wearing protective gloves as they are harmful by skin absorption as well as inhaling, young children and pets should be kept well away until the treated article is thoroughly dry. Once dry and sealed with varnish or sealer the item is safe. Hope this helps..... I actually ran a timber treatment company for many years, hope I haven't bored you with too much technical info.
