The differential diagnosis of perio-endo lesions has become increasingly important as the demand for complicated restorative work has grown. Neither periodontic nor endodontic treatment can be considered in isolation as clinically they are closely related and this must influence the diagnosis and treatment. The influence of infected and necrotic pulp on the periapical tissues is well known, but there remains much controversy over the effect that periodontal disease could have on a vital pulp.
Examination of the anatomy of the tooth shows that there are many paths to be taken by bacteria and their toxic products between the pulp and the periodontal ligament. Apart from the main apical foramina, lateral canals exist in approximately 50% of teeth, and may be found in the furcation region of permanent molars.
Seltzer et al. observed inter-radicular periodontal changes in dogs and monkeys after inducing pulpotomies and concluded that noxious material passed through dentinal tubules in the floor of the pulp chamber.
In addition to dentinal tubules, microfractures are often present in teeth, allowing the passage of microorganisms. Clinically, it is common to see cervical sensitivity.
The controversy concerning the effect of periodontal disease on the pulp ranges between those who believe that pulpitis or pulp necrosis or both can occur as a result of periodontal inflammation, to those who state categorically that pulpal changes are independent of the status of the periodontium. In the author s opinion, Belk and Gutmann present the most rational view, which is that periodontal disease may damage pulp tissue via accessory or lateral canals, but total pulpal disintegration will not occur unless all the main apical foramina are involved by bacterial plaque (Fig. 9).
Examination of the anatomy of the tooth shows that there are many paths to be taken by bacteria and their toxic products between the pulp and the periodontal ligament. Apart from the main apical foramina, lateral canals exist in approximately 50% of teeth, and may be found in the furcation region of permanent molars.
Seltzer et al. observed inter-radicular periodontal changes in dogs and monkeys after inducing pulpotomies and concluded that noxious material passed through dentinal tubules in the floor of the pulp chamber.
In addition to dentinal tubules, microfractures are often present in teeth, allowing the passage of microorganisms. Clinically, it is common to see cervical sensitivity.
The controversy concerning the effect of periodontal disease on the pulp ranges between those who believe that pulpitis or pulp necrosis or both can occur as a result of periodontal inflammation, to those who state categorically that pulpal changes are independent of the status of the periodontium. In the author s opinion, Belk and Gutmann present the most rational view, which is that periodontal disease may damage pulp tissue via accessory or lateral canals, but total pulpal disintegration will not occur unless all the main apical foramina are involved by bacterial plaque (Fig. 9).
The problem that faces the clinician treating perio-endo lesions is to assess the extent of the disease and to decide whether the tooth or the periodontium is the primary cause. Only by carrying out a careful examination can the operator judge the prognosis and plan the treatment.
There are several ways in which perio-endo lesions can be classified; the one given below is a slight modification of the Simon, Glick and Frank classification.