Prosthodontics, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey
報告者姓名(組別)： Int G 組黃渝聖
報告日期： 100/2/8
內文：
Introduction
a complete or incomplete fracture line extending obliquely or longitudinally through the enamel and dentin of teeth
VRFs usually result in extraction
Major iatrogenic and pathologic risk factors for VRFs
excessive root canal preparation,
overzealous lateral and vertical compaction forces during root canal filling,
moisture loss in pulpless teeth
overpreparation of post space
excessive pressure during post placement
compromised tooth integrity as a result of large carious lesions or trauma A multi-rooted tooth with VRF can be conserved by resecting the involved root No specific treatment modality has been established
The extraoral bonding of fractured segments with an adhesive resin cement and intentional replantation of teeth after reconstruction
The diagnosis of VRF:often requires prediction rather than definitive identification Conventional periapical (PA) radiographs
VRF might lead to bone loss, pain, and malfunction of the involved area cone-beam computed tomography (CBCT)
Procedures
CBCT scans were taken of each patient by using 0.2-mm voxel size, 6-cm field of view (FoV), 120 kV, and 5 mA.
Classified into 2 groups according to type (hairline versus separated) and location preoperative oral hygiene instruction
steps
Local anesthesia by using a solution of 2% articaine with 1:1000 epinephrine
A full-thickness mucoperiosteal flap
supra-alveolar fibers were circumferentially dissected
The tooth was gently extracted to protect the periodontium
Each extracted tooth was immediately immersed in saline solution (0.9%
isotonic NaCl)
The socket walls adjacent to the fracture region were curetted and irrigated
extraction of affected teeth while avoiding periodontal damage
bonding of the separated segments with a self-etching dual-cure adhesive resin cement(Panavia F 2.0)
Intentional replantation of the reconstructed teeth
2 hairline-like VRFs were prepared as a shallow preparation
VRFs through the entire root were treated by removing the root-filling material
Use tetracycline 30 sec for enhancing PDL attachment
Extroral procedure:16~28 min
Keep moistened during curing
Rx:chlorhexidine mouth rinse
3x500 mg amoxicillin daily for 1week 2x550 mg naproxen daily for 1week
All affected teeth were restored with full-cast crowns 2–6 months after reconstruction and intentional replantation
Clinical success
lack of sensitivity to percussion
percussion tone that did not differ from the healthy adjacent teeth
mobility within normal limits at 6 months
reduction in periapical radiolucency
Case 1
complained of chronic dull pain in the left anterior maxilla.
large composite resin restorations in the maxillary incisors and canines
an incomplete hairline-like on the left maxillary canine23
Six months later, teeth were asymptomatic clinically
22 23
Case 2
A 25-year-old woman complained of mild pain in her maxillary left lateral incisor during chewing
Endodontic treatment 2 years ago
buccal and palatal periodontal pockets averaged 5 mm in depth
CBCT scans revealed a hairline-like VRF on the apical and middle thirds of the root
After 8 months, The tooth was asymptomatic
PA radiolucency was reduced at the end of 2 years
Case 3
A 32-year-old man complaining of draining pus and chronic dull pain in the right anterior region of the maxilla.
Clinical examination revealed a separable distal fracture on the maxillary right canine 13
A polyethylene fiber (Ribbond; Ribbond Inc, Seattle, WA) was adhered on the root dentin to form a post for retention
The tooth was asymptomatic, with physiologic mobility 2 years later
Discussion
The way to detect VRFs 1illumination
2x-rays
3periodontal probing 4staining
5surgical exploration 6bite tests
7direct visualization of the fracture 8operative-microscope examination 9CBCT scanning
Rapid diagnosis of a VRF is required to prevent additional bone loss that will furtherimpede reconstruction.
VRF treatment that included resin cement bonding and intentional replantation
of gingival health
use of a dual-curing material shortened extraoral working time and preserved the vitality of the periodontal ligament
Hayashi et al addressed the imperfect curing of the light-cured adhesives at the apical portions
Recent studies have reported that the use of 4-META/MMA-TBB resin, a self-cure adhesive resin cement, leads to successful VRF reconstruction outcomes
dual-cure adhesive resin cements are preferable
These cements achieve controlled polymerization , are easy to apply, have short curing times
Andreasen et al treated the roots of 2 incisors with apicoectomy and retrograde dentin-bonded composite filling, concluding that the tissue accepted the composite as a base for cementogenesis
Healthy cementum on the root surface and periodontal membrane vitality are important factors in preventing ankylosis
Solutions such as citric acid, tetracycline, and ethylenediaminetetraacetic acid have been advocated for root surface modification
A 30-second application of tetracycline has been reported to successfully remove the smear layer, leaving clean and open tubules
Ankylosis
Ankylosis can be demonstrated 2 weeks after replantation
The percussion test can often reveal replacement resorption in its initial phases before it can be diagnosed radiographically
Radiographic examination is considered to be of limited value in the early detection of ankylosis
Usually on buccal and lingual side
ankylosis might occur after 5–10 years
the CBCT imaging system used does not exceed 0.020 mm, which is the average width of the periodontal ligament space
CBCTs are categorized as the following:
(1) small volume used to scan a few teeth or one jaw
(2)medium volume, involving both jaws, the maxillary sinus, and part of the nose
(3) large volume, covering the entire maxillofacial region
The smaller the scan volume, the higher is the spatial resolution of the image
In our cases, Next-Generation i-CAT (medium FoV) was used with a 0.2-mm voxel size
The images were unable to clearly demonstrate cracks as a result of the decreased resolution
As previously reported by Hassan et al , axial slices were more accurate than coronal and sagittal slices in detecting VRF.
Sagittal-plane images were useful for determining the extent and direction of each fracture line
clinical signs and symptoms are fundamental and very important for the diagnosis of fractures, and one must consider the signs and symptoms too
CBCT provides enhanced and accurate information
Conclusions
Scanners with smaller FoVs with higher resolutions would be advisable for use in detecting VRFs and in the follow-up period
Bonding the separated fragments of VRFs extraorally and intentional replantation of the reconstructed tooth are an innovative method
Further long-term studies of treatment outcomes are necessary
答案(D) 出處：Diagnosis and Treatment of Endodontically Treated Teeth with Vertical Root Fracture: Three Case Reports with Two-year Follow-up J
Endod 2011;37:97-102
題號 題目
2 Ankylosis 通常發生在牙齒的哪個面
(A) Buccal (B) Lingual (C) Proximal (D) A+B
答案(D) 出處：Diagnosis and Treatment of Endodontically Treated Teeth with Vertical Root Fracture: Three Case Reports with Two-year Follow-up J
