ABSTRACT
The mandibular second molar has many root canal variations. This investigation used two evaluation methods to examine the canal morphology of mandibular second molars having C-shaped canals. Fifteen extracted mandibular second molars with a conical root and C-shaped canal orifice were separated into two groups. A polyester cast resin technique allowed three-dimensional visualization of the root canal system in eight teeth; the remaining seven molars were prepared for histological examination in cross-section in the coronal, middle, and apical thirds for study under the light microscope. The results illustrated that C-shaped canals in mandibular second molars can vary in number and shape along the length of the root with the result that debridement, obturation, and restoration in this group may be unusually difficult.
Subject(s)
Dental Pulp Cavity/anatomy & histology , Molar/anatomy & histology , Tooth Root/anatomy & histology , Adolescent , Adult , Humans , MandibleABSTRACT
This study evaluated whether a single or double injection is required to achieve first molar anesthesia. Subjects received posterosuperior alveolar nerve blocks. Presence or absence of anesthesia was evaluated with carbon dioxide dry ice pulp sensitivity testing. This was followed by mesial infiltration and a second pulp testing. The posterosuperior alveolar nerve block alone usually provided effective first molar anesthesia. A small percentage of subjects required an additional mesial infiltration to obtain anesthesia.
