This paper presents a clinical and anatomical review of the mental foramen (MF) based on recent publications (since 1990). Usually, the MF is located below the 2nd premolar or between the two premolars, but it may also be positioned below the 1st premolar or below the mesial root of the 1st molar. At the level of the MF, lingual canals may join the mandibular canal (hence the term "crossroads"). Accessory MF are frequently described in the literature with large ethnic variations in incidence. The emergence pattern of the mental canal usually has an upward and posterior direction. The presence and extent of an "anterior loop" of the mental canal may be overestimated with panoramic radiography. Limited cone-beam computed tomography currently appears to be the most precise radiographic technique for assessment of the "anterior loop". The mental nerve exiting the MF usually has three to four branches for innervation of the soft tissues of the chin, lower lip, facial gingiva and mucosa in the anterior mandible. The clinician is advised to observe a safety distance when performing incisions and osteotomies in the vicinity of the MF.
For dental care professionals, the availability and cleanliness of reusable instruments is of major importance. In order to guarantee a proper reprocessing (cleaning, sterilization) of each instrument and ensure optimum safety for the patients, a single instrument traceability solution can be implemented. The RFID (Radio Frequency Identification) technology is the only approach that can provide a fully automated identification of instruments, and a precise monitoring throughout the reprocessing cycle. It consists in integrating a miniature electronic component (RFID tag) to each instrument able to communicate with a transmitter located at a relatively close distance and capable of uniquely identifying each element in any given container, even when closed. In 2011, a pilot project was implemented in collaboration with the Division of Dentistry (SMD) of the University of Geneva and the central sterilization of the Geneva University Hospitals (HUG). This project has demonstrated the applicability and usefulness of RFID technology for tracking reusable dental instruments. In particular, the time saved by the operators and the massive risk reduction when compared to the possible errors during the process of manual identification are two major elements that justify the implementation of an RFID-based instrument traceability solution.
The aim of this randomized, controlled clinical study was to compare the short-term effects of nonsurgical periodontal therapy with the additional administration of systemic antibiotics (AB) and the same therapy with additional photodynamic therapy (PDT) in the treatment of patients with aggressive periodontitis (AP). Thirty-six patients with AP received full-mouth nonsurgical periodontal treatment (SRP) and were then randomly divided into two groups of 18 subjects each. Group AB received amoxicillin and metronidazole three times a day for 7 days. Group PDT received two applications of PDT on the day of SRP as well as at follow-up after 7 days. The following clinical parameters were measured at baseline and 3 months after therapy: plaque index (PLI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL). After 3 months, PD was significantly reduced in both groups (from 5.0±0.8 mm to 3.2±0.4 mm with AB, and 5.1±0.5 mm to 4.0±0.8 mm with PDT; both p<0.001), while AB revealed significantly lower values compared to PDT (p = 0.001). In both groups, GR was not significantly changed. CAL was significantly reduced in both groups (PDT: 5.7±0.8 mm to 4.7±1.1 mm; p=0.011; AB: 5.5±1.1 mm to 3.9±1.0 mm; p<0.001) and differed significantly between the groups (p=0.025). The number of residual pockets (PD ≥4 mm) and positive BOP was reduced by AB from 961 to 377, and by PDT from 628 to 394. Pockets with PD ≥7 mm were reduced by AB from 141 to 7, and by PDT from 137 to 61. After 3 months, both treatments led to statistically significant clinical improvements. The systemic administration of antibiotics, however, resulted in significantly higher reduction of PD and a lower number of deep pockets compared to PDT.
Root perforations as a possible complication during a root canal treatment may increase the risk of failure for the affected tooth. The influencing factors include: the location and the size of the perforation, a potential microbial colonization of the endodontic system, the time lapse between the occurrence of the perforation and repair, and the filling material. Decontamination at the perforation site and in the remaining root canal system is essential for long-term success. For most cases, an orthograde retreatment with perforation repair represents a reasonable causal-based approach. This case report documents the treatment of a maxillary incisor with extensive apical periodontitis and iatrogenic root perforation in a 14-year-old patient. Three years after retreatment, perforation repair and coronal restoration with composite the follow-up shows a successful treatment outcome.