Coronal structure compromise and anticipated force in anterior abutment teeth as failure risk for full coverage retainers of fixed dental prostheses.
Fazal Ghani*, Zulfiqar Nazir **. *Department of Prosthodontics, Peshawar Dental College, Warsak Road, Peshawar 26160 (Pakistan). ** Department of Prosthodontics, Bacha Khan Dental College, Mardan (Pakistan).
Objectives: Despite being widely prescribed, failures and complications are not uncommon in fixed dental prostheses (FPDs). One reason for failure may be the use of abutments with compromised coronal structure. It is aimed to document various levels of failure risk severity for full coverage FPD retainers placed in anterior teeth with coronal structural compromise and extent of anticipated forces placed on them. Methods: Data were collected from 97 subjects fulfilling the inclusion and exclusion criteria for the study using the method of clinical examination and measurements on the casts of abutments prepared for FPDs. The level of severity of failure risk was determined from the number of remaining wall(s) and the extent of overbite. Level of risk was low in teeth having one lateral wall missing or teeth with two walls missing subjected to light lateral loads. Moderate level risk included teeth having two lateral walls missing subjected to heavy lateral loads or teeth having buccal or lingual wall missing subjected to light lateral load. High risk level included teeth having compromised buccal or lingual wall subjected to heavy forces or any tooth having both lateral walls missing or having only one wall or no wall present irrespective of type of lateral load. Results: Out of 97 subjects 56 (57.7%) were males and 41 (42.3%) were females with a male to female ratio of 1.4:1. Mean age of the patient was 36.7±9.78 (SD). Most common tooth involved was tooth number 9 (26.8%). Least common teeth involved were tooth number 25 and 26 (1%). Moderate level failure risk severity was more prevalent (49.5%) than low level (28.6) and high level (23.7). Most commonly involved teeth were maxillary lateral incisors. Furthermore, almost all teeth involved were the maxillary teeth. Conclusions: Irrespective of the tooth involved, moderate level of failure risk severity was more common.