Mapping out the surgical anatomy of the lingual nerve: a systematic review and meta-analysis.

Objectives: Understanding the lingual nerve's precise location is crucial to prevent iatrogenic injury. This systematic review seeks to determine the lingual nerve's most probable topographical location in the posterior mandible. Materials and Methods: Two electronic databases were searched, identifying studies reporting the lingual nerve's position in the posterior mandible. Anatomical data in the vertical and horizontal dimensions at the retromolar and molar regions were collected for meta-analyses. Results: Of the 2,700 unique records identified, 18 studies were included in this review. In the vertical plane, 8.8% (95% confidence interval [CI], 1.0%-21.7%) and 6.3% (95% CI, 1.9%-12.5%) of the lingual nerves coursed above the alveolar crest at the retromolar and third molar regions. The mean vertical distance between the nerve and the alveolar crest ranged from 12.10 to 4.32 mm at the first to third molar regions. In the horizontal plane, 19.9% (95% CI, 0.0%-62.7%) and 35.2% (95% CI, 13.0%-61.1%) of the lingual nerves were in contact with the lingual plate at the retromolar and third molar regions. Conclusion: This systematic review mapped out the anatomical location of the lingual nerve in the posterior mandible, highlighting regions that warrant additional caution during surgeries to avoid iatrogenic lingual nerve injuries.

Maxillary Impaction Does Not Negatively Affect the Nasal Airway: A Systematic Review With Meta-Analysis.

PURPOSE: Le Fort I maxillary impaction is an orthognathic surgical procedure to reposition the maxillary complex superiorly. The objective of this study is to investigate if maxillary impaction negatively affects the nasal airway. METHODS: A systematic review with meta-analysis was performed to investigate the effects of maxillary impaction on the nasal cavity. PubMed, Embase, and Cochrane Library databases were accessed. Observational studies, nonrandomized, and randomized controlled trials were included if Le Fort 1 maxillary impaction and nasal airway outcomes assessments were performed. Studies were excluded if maxillary impaction or nasal airway outcome assessment was not performed or if the study included patients with cleft or craniofacial syndromes, previous nasal surgeries, or active respiratory tract. The demographic data, study methodology, magnitude of maxillary impaction, and outcomes related to the nasal airway were collected. These outcomes includes anatomical changes (evaluated by rhinoscopy, acoustic rhinometry, and computed tomography), changes to nasal airflow and resistance (evaluated by rhinomanometry) and changes to quality of life. RESULTS: The search yielded 7517 studies. Ten studies were included after the application of the selection criteria. A total of 126 patients underwent pure maxillary impaction, 97 underwent maxillary impaction and advancement, and 12 had impaction with setback. Despite that maxillary impactions decreased the nasal cavity volume by +21.7%, the cross-sectional area of the narrowest parts of the cavity was only reduced by -8.4%. Maxillary impactions generally increases the nasal airflow (+12.6%) while reducing nasal resistance (-20.2%). Rhinoscopies also showed a reduction in nasal obstruction. CONCLUSION: Maxillary impaction did not negatively affect the nasal airway. The surgeries did not lead to the reduction of the cross-sectional area at the strictures of the nasal cavities. The nasal airflow and resistance was not decreased and increased, respectively. The quality of life of the patients was also not shown to have worsened.

Healing complications and their detrimental effects on bone gain in vertical-guided bone regeneration: A systematic review and meta-analysis.

PURPOSE: Guided bone regeneration (GBR) utilizes a barrier membrane to allow osteogenic cells to populate a space by excluding epithelial and connective tissue cells. The purpose of this systematic review was to investigate the ratio of means (RoM) of vertical bone gained (Outcome) in vertical GBR procedures with healing complications (Intervention) and in vertical GBR procedures without healing complications (Comparison) in patients with vertically resorbed edentulous ridges that require dental implant placement (Population). A further aim was to investigate the incidence of complications after vertical GBR, and the influence of the timing of implant placement and regenerative devices on complications. MATERIALS AND METHODS: MEDLINE (through PubMed), EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched in duplicate up to, and including, November 2020 for randomized and controlled clinical trials and prospective and retrospective case series. Outcomes included patient-level and site-level RoM of vertical bone gain between healing complications and uneventful healing, and incidences of complications that occurred after vertical GBR. Random-effects and fixed-effects meta-analyses were performed where appropriate. This study was registered on PROSPERO (CRD42021226432). RESULTS: A total of 31 publications were selected for the qualitative and quantitative analyses. The RoM of vertical bone gained was 0.65 [95% CI = 0.47, 0.91] and 0.62 [95% CI = 0.45, 0.85] when membrane exposure without suppuration and abscess formation without membrane exposure occurred respectively, in comparison to uneventful healing. The overall incidence proportion of healing complications occurring at the augmented site at a site- and patient-level was 11.0% [95% CI = 7.0, 15.6] and 10.8% [95% CI = 6.6, 15.7]. At a patient-level, there were no significant differences between a simultaneous or staged approach, or with the regenerative device used. The site-level incidence proportion of membrane exposure without suppuration, membrane exposure with suppuration, and with abscess formation without membrane exposure was 8.7% [95% CI = 4.2, 14.2], 0.7% [95% CI = 0.0, 2.9], and 0.5% [95% CI = 0.0, 1.7], respectively. The site-level weighted mean incidence proportion of neurologic complications occurring at the donor site was 0.8% [95% CI = 0.0, 5.3]. CONCLUSIONS: There is a significant reduction in bone gain when healing complications occur. However, healing complications are relatively uncommon surgical complications after vertical GBR.

Postobturation Pain Associated with Tricalcium Silicate and Resin-based Sealer Techniques: A Randomized Clinical Trial.

INTRODUCTION: The incidence of immediate postobturation pain associated with 2 sealer techniques was compared and potential prognostic factors identified. METHODS: Patients referred for endodontic treatment were recruited with informed consent. Root canals were debrided and teeth rendered asymptomatic before random allocation to receive TotalFill BC (FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) or AH Plus sealer (Dentsply Maillefer, Ballaigues, Switzerland). Patients blinded to the sealer reported their postobturation pain experience 1, 3, and 7 days after treatment. Blinded and calibrated assessors independently reviewed treatment quality, sealer extrusion, and radiographic data under standardized conditions. RESULTS: One hundred sixty eligible patients (163 teeth, 95.3%) returned their pain diary. No postobturation pain difference was found between the 2 sealers (P > .05), although the AH Plus sealer technique was significantly associated with extrusion beyond the apex (P < .05; odds ratio [OR] = 3.02; 95% confidence interval [CI], 1.39-6.57). Thirty-three (20.6%) patients reported pain on day 1 (median 1 = very mild pain), 16 (10.0%) on day 3 (median 1 = very mild pain), and 9 (5.6%) on day 7 (median 2 = mild pain). The prognostic factors were as follows: (1) moderate/severe preoperative pain (OR = 4.41; 95% CI, 1.42-13.76 on day 3 and OR = 5.16; 95% CI, 1.17-22.78 on day 7), (2) provoked preoperative pain (OR = 4.24; 95% CI, 1.40-12.78 on day 3 and OR = 5.35; 95% CI, 1.27-22.51 on day 7), (3) pulpless tooth (OR = 0.11; 95% CI, 0.02-0.57 on day 3), and (4) sonic activation during treatment (OR = 3.02; 95% CI, 1.39-6.57 on day 1 and OR = 3.01; 95% CI, 1.05-8.59 on day 3). CONCLUSIONS: There was no significant difference in pain experience between teeth filled using AH Plus or TotalFill BC Sealer 1, 3, and 7 days after obturation. Patient- and treatment-related factors could influence postobturation pain.

Clinical and histological sequelae of surgical complications in horizontal guided bone regeneration: a systematic review and proposal for management.

It is not uncommon to encounter post-surgical complications after horizontal guided bone regeneration (GBR). The primary aim of this review was to evaluate the incidence and types of complications that occur after horizontal GBR and propose management strategies to deal with these clinical situations. A secondary aim was to conduct a histomorphometric review of the wound healing process at sites that experienced post-surgical complications after GBR. A keyword search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials for studies published in English from January 2015 to January 2020 was conducted for the primary aim and 23 studies were selected. A second search addressing the secondary aim was conducted, and five studies were included. Site-level analysis showed that the weighted mean incidence proportion of minor wound dehiscence and minor infections occurring at the augmented site was 9.9% [95% CI 6.4, 13.9, P < 0.01] and 1.5% [95% CI 0.4, 3.1, P = 0.21) respectively. Patient-level analysis showed minor and major complications occurring at a weighted mean incidence proportion of 16.1% [95% CI 11.9, 20.8, P = 0.01] and 1.6% [95% CI 0.0, 4.7, P < 0.01] respectively, while neurosensory alterations at the donor site was 7.0% [95% CI 1.3, 15.5, P < 0.01]. Subgroup analysis also revealed that the use of block grafts increased the incidence proportion of minor post-surgical complications, whereas a staged GBR procedure increased the incidence proportion of both minor and major post-surgical complications. Although exposure of the barrier membrane is often associated with less bone regeneration and graft resorption, the type of membrane used (resorbable or non-resorbable) had no statistically significant influence on any post-surgical complication. Histologically, a layer of fibrous connective tissue instead of bone is commonly observed at the interface between the native bone at the recipient site and the regenerated bone in cases with membrane exposure after GBR procedure. Minor wound dehiscence was the highest incidence proportion of post-surgical complications. Methods ranging from daily application of antiseptics, use of systemic antimicrobials, regular reviews, and total removal of the non-integrated biomaterials are commonly prescribed to manage these post-surgical complications in attempt to minimise the loss of tissue at the surgical site.