Treatment planning is  based on multiple factors; expense, time and technical considerations. Here is an asymptomatic upper left second molar with no opposing dentition. The tooth has lost a lingual amalgam and has extensive mesial-buccal subgingival decay. The patient cannot afford to correct the bite collapse or replace the lower dentition.

Following administration of local anesthesia (topical plus Xylocaine with 1:50,000 epinephrine… to control the bleeding when removing subgingival decay) the amalgam and all decay were removed. Fortunately there was no pulpal exposure. If this had been the case and endodontic therapy would have been necessary, extraction might have been the only affordable alternative.

When removing the subgingival decay, gingival retraction cord was placed to help isolate the area. Placing a matrix band would have been another option. Establishing a good contact with the adjacent tooth was not feasible. Only an indirect laboratory fabricated restoration would have allowed this anatomy. The space is accessible for cleaning.