Impact of Retro-molar Pad Demarcation on Complete Denture Wearers' Satisfaction and Quality of Life: a Cross-over, Double-blind Clinical Trial.

The retromolar pad is a key intraoral anatomical landmark in removable prosthodontics. It comprises of non-keratinized loose alveolar tissue covering glandular tissues and muscle fibers. The denture base should extend to cover the retromolar pad. There are variations in the anatomical shape of the retromolar pad, however, no reports in the literature to record that area on the cast and to measure its effect on the retention of the lower denture.

The retromolar pad is a key intraoral anatomical landmark in removable prosthodontics. The denture base should cover the retromolar pad not only to provide proper peripheral seal but also for stability of the denture by adding another plane to resist movements of the base. Furthermore, it remains a stable landmark even in advanced ridge resorption. It is also considered a crucial landmark to determine the occlusal plane where the later terminates posteriorly in the middle of the upper third of the retromolar pad. The mandibular first molar is usually found at the level corresponding to the anterior two thirds of the retromolar pad area. The pad comprises of non-keratinized loose alveolar tissue covering the glandular tissues, fibers of buccinator muscle, fibers of superior constrictor muscle, fibers of ptergomandibular raphe and the terminal part of the tendon of temporalis muscle. After the molars are lost the bone and surrounding soft tissues remodels, resorbs and blends with retromolar pad. The mylohyoid muscles and the buccinator muscles affixed to nearby bony areas are some of the barriers to the chronic but limited bone resorption of the retromalr pad, following tooth loss, time of edentulism, systemic factors, and denture wear.

There are variations in the anatomical shape (pear, triangular and circular) and size of retromolar pad area both in the same patient and in different patients. It was reported that the denture posterior border should be defined at least more posteriorly than in the 2/3 of the retromolar pad (positioned about 7mm distal to the anterior margin of the retromolar pad) and preferably as much as possible to be extended to the distal end dome of the retromolar pad (about 15mm from the anterior margin of the retromolar pad).

The lower denture is usually less retentive than the upper denture due to the reducced surface area covered. The retromolar pad area defines the posterior end of the denture and helps in the retention and stability of the lower denture, however no reports in the literature to record that area on the cast and to measure its effect on retention. Therefore, this clinical study aims to evaluate the effect of carving the retromolar pad area on the retention of the lower denture.

Therefore this clinical study aims to evaluate the effect of carving the retromolar pad area on the retention of lower denture. 50 edentulous patients with no previous denture history will be recruited. Complete dentures will be constructed for each patient with two sets of mandibular dentures by one prosthodontist. One conventional lower denture and one denture with added rertomolar pad whereby one of the dentures will be delivered and after one month the second denture is delivered. Both dentures will be assessed one month after insertion using validated questionnaires. Clinical assessment of the dentures will be performed by two blind prosthodontists on a visual analogue scale. Data will be analyzed using SPSS software.