Is failure of condylar neck osteosynthesis predictable based on orthopantomography?

Evaluation of clinical and radiographic warning signs for prediction of oroantral communication following tooth extractions

OBJECTIVES

Oroantral communication (OAC) is a relatively common and mild complication of maxillary tooth extractions. Preoperative prediction of OAC can reduce treatment duration and prepare both operators and patients for the procedure. This study aims to identify alarming radiographic and clinical indicators that can predict OAC therefore assisting clinical decision making to practicing general dentists.

METHODS

In this retrospective case-control study the OAC group consisting of 97 cases and a control group twice the size was established. Clinical data were collected, and measurements were conducted separately by two blinded observers on digital panoramic radiographs. Inter-rater reliability was assessed. In case of disagreement a third observer's results were utilized. The correlation between OAC and demographic data (age, sex), as well as various factors assessed on panoramic radiographs (including, but not limited to, the length of the root, root projection into the sinus, bone width, presence of mesial and distal adjacent teeth), was statistically evaluated.

RESULTS

Inter-rater reliability was found to be excellent. Several factors were identified as potential predictors of OAC. According to our model, the strongest predictors were the distance between the cemento-enamel junction and marginal bone, extent of root projection into the sinus, presence of sinus recess around the roots, angulation, and absence of the mesial adjacent tooth.

CONCLUSIONS

Well-defined measurements on panoramic radiographs may aid in predicting OAC. Further prospective investigations are necessary to confirm these indicators and address factors related to clinical examination and operation.

CLINICAL RELEVANCE

We present several clinical and radiographic warning signs of OAC that can facilitate pre-extraction decision-making.

The Stability Evaluation of Two Internal Fixation Patterns of Extracapsular Condylar Fracture Based on One Novel Measuring Method

PURPOSE

The most stable internal fixation pattern for extracapsular condylar fracture (ECF) has been controversial. In this study we aimed to evaluate the stability of 2 common internal fixation patterns using 1 or 2 miniplates separately. One novel measuring method based on the angle of miniplates' localization was introduced.

MATERIALS AND METHODS

Twenty-seven patients with 30 sides of extracapsular condylar fracture were enrolled in this retrospective study. All cases were performed open reduction and internal fixation using 1 or 2 titanium plates with both the postoperative immediate CT (T1) and the over 6 months' follow-up CT (T2). Mandibles and implants were segmented and reconstructed respectively using SIMPANT 14.04 software. For 1 miniplate group, the sagittal crossing angle (<1) between miniplate (P1) and posterior border of ipsilateral ramus was measured. For 2 miniplates group, the sagittal crossing angle (<2) between 2 miniplates (P2a, P2b) was measured. Both anteroposterior (∠AP) and mediolateral angle change (∠ML) of each miniplate between T1 and T2 was measured. The stability of 2 internal fixation patterns was measured and evaluated based on the angle change of miniplates. And also the stability of each internal fixation pattern could be investigated based on the relationship between the placement patterns of miniplates and the angle change.

RESULTS

Fifty-two miniplates were finally segmented and reconstructed successfully, including 8 of 1 miniplate group and 44 of 2 miniplate group. For 1 miniplate group, the average ∠AP and ∠ML were 6.10° and 8.54°, respectively. For 2 miniplate group, the average ∠AP and ∠ML of P2a were 3.02° and 2.56°, respectively, as well as 3.12° and 3.07° of P2b.

CONCLUSIONS

The novel measuring method based on the angle of miniplates' localization showed potential for the stability evaluation of internal fixation of condylar fracture. In summary, the internal fixation patterns using 2 miniplates shows better stability than that of 1 miniplate.

Evaluation of an experimental oblique plate for osteosynthesis of mandibular condyle fractures

OBJECTIVE

The aim of this study was to test the bone thickness and potential screw length for osteosynthesis of condylar base fractures (according to the Loukota classification) with an experimental titanium plate, placed in an ideal position against 2 types of conventional plates.

STUDY DESIGN

After exclusion of completely edentulous mandibles, 28 dentate macerated mandibles available at the time of the study were included. Linear regression models 1 and 2 compared the sums of the 2 cranial bone thicknesses and the 3 caudal thicknesses among the 3 different plate designs, and linear models 3 and 4 tested the bone thickness in the 2 most cranial screw axes.

RESULTS

Linear models 1 and 2 revealed significantly higher potential screw lengths for the experimental oblique plate. Equally, linear models 3 and 4 indicated significantly higher bone thickness for the novel oblique plate.

CONCLUSION

The novel proposed oblique plate allows for favorable plate positioning in a biomechanically ideal location with sufficient amounts of local bone for stable plate fixation. When plates with 15-degree angulated screw holes are used, stable bicortical plate fixation can be achieved.

Epidemiology and treatment outcome of surgically treated mandibular condyle fractures. A five years retrospective study

Surgical management of mandibular condyle fractures is still controversial. Although it provides better outcome than closed treatment questions still remain about the surgical approach and the osteosynthesis devices to be used. Between 2005 and 2010, we managed 168 mandibular condyle fractures with open treatment. Two surgical approaches were used in this study, a pre-auricular and a high submandibular approach (one or the other or as a combined approach). Internal fixation was performed using TCP(®) plates (Medartis, Basel, Switzerland) or with two lag screws (15 and 17 mm). Delta plates were used in 15 cases (8.9%). We report the epidemiology of these fractures and the outcomes of the surgical treatment. We assessed the complications related to the surgical procedure and those related to the osteosynthesis material. The facial nerve related complication rate was very low and the osteosynthesis materials used proved to be strong enough to realize a stable fixation. The two approaches used in this study appeared to be safe with good aesthetic results. Most of the surgical procedure failures occurred in high subcondylar fractures especially when bilateral.