Molar apicectomy with amalgam root-end filling: results of a prospective study in two district general hospitals

To determine the five-year success rates, site or sites of failure, prognostic indicators and lower lip morbidity associated with molar apicectomy using amalgam root-end filling.

Multicentre, prospective study.

The departments of oral and maxillo-facial surgery in two district general hospitals.

One thousand and seven molar apicectomy procedures, combined with amalgam root-end filling were expedited during the period 1974-1995. A five-year review of each operated tooth was carried out or attempted between 1979-2000.

Of the 790 (78%) operated molars successfully reviewed at 5 years or later 451 (57%) exhibited 'complete healing' and 39 (5%) 'uncertain healing'. Three hundred (38%) were classified as 'unsatisfactory healing' (failures), and these included 12 which were assumed to be of periodontal origin. Whilst longitudinal root fracture, perforation and/or infection in the furcation, periodontal disease or a non-restorable crown accounted for treatment failure and often the need to remove teeth subsequently, the study probably pointed to the apical ends of the roots rather than the furcation as being the major sites at which 'unsatisfactory healing' occurred. Mandibular first molars attracted the highest 'complete healing' rate (60%) and mandibular second molars the lowest (46%). 'Good' root canal treatment (RCT) at the outset improved the prognosis of a root-end filling (REF) whilst the absence of RCT compromised it. Cystic change pointed to a better prognosis than apical granulomatous change as did a deep compared with a shallow 'bone cuff'. Disease at the furcation suggested a worse prognosis. Teeth which showed 'complete healing' at 1 year had a 75% probability of maintaining this outcome at 5 years. Sensory disturbance of variable duration occurred in the lower lip following 20-21% of mandibular molar procedures. In the majority of cases (79-80%) this had remitted within 3 months. A permanent deficit occurred in 8 patients (1%) where the apicectomy could definitely be incriminated as causative. Four were associated with first molar apicectomy and four with second molar apicectomy.

Molar apicectomy with amalgam root-end filling attracts an overall 'complete healing' rate at 5 years of 57%, the results being best with mandibular first molars and worst with mandibular second molars. The prognosis is also better where there is 'good' initial orthograde root filling, an associated radicular cyst as compared with granulomatous change and where the buccal sulcus is deep rather than shallow. It is worse when orthograde root filling is absent and when there is disease in the furcation. 'Complete healing' at 1 year can be expected to be maintained at 5 years in 75% of cases. The commonest site of subsequent periradicular rarefaction seems to be 'apical' whilst failure at the furcation is probably comparatively rare. There is a threefold increase in the occurrence of permanent lower lip sensory impairment following second molar surgery in comparison with first molar surgery, the overall incidence being 1%.