Objectives: The restoration of edentulous posterior maxilla
with dental implants is challenging due to a deficient posterior
alveolar ridge. Over the last decade an advance in the graftless bone
augmentation procedures had occurred where the space left beneath the
Schneiderian membrane is filled with blood clot in order to produce bone
formation. The aim of present article is to review the scientific
literature with respect to bone formation in the sinus, after membrane
elevation procedure, without using any bone substitutes.
Material and Methods: A comprehensive review of the current literature was
conducted according to the PRISMA guidelines by accessing the NCBI PubMed
database. The articles were searched from 1993 to 2013. English language
articles with minimum one year patient follow-up and radiological and/or
histological diagnostics of newly formed bone were included. Articles were
excluded, if usage of bone graft or bone substitutes and/or usage of osteotome
has been made during sinus lift operation.
Results: A total of 19
studies were included: 2 studies were related to the sinus membrane’s osteogenic
potential, 3 to the histological evidence of bone formation in monkeys and
humans, 12 to the radiologic evidence of bone gain, and 2 to the
space-maintaining management. 100% of the reviewed articles presented with
increased bone formation and high implant survival rates resulting from the
graft-free technique.
Conclusions: It is clearly shown in the
review that the potential of the maxillary sinus to heal and to form new bone
without bone grafts or substitutes is of high nature.
Comparative Study of Skeletal Stability between Postoperative
Skeletal Intermaxillary Fixation and No Skeletal Fixation after
Bilateral Sagittal Split Ramus Osteotomy: an 18 Months
Retrospective Study
Jens Hartlev, Erik Godtfredsen, Niels Trolle Andersen, Thomas
Jensen
Objectives: The purpose of the present study was to evaluate
skeletal stability after mandibular advancement with bilateral sagittal
split osteotomy.
Material and Methods: Twenty-six patients
underwent single-jaw bilateral sagittal split osteotomy (BSSO) to correct
skeletal Class II malocclusion. One group (n = 13) were treated postoperatively
with skeletal elastic intermaxillary fixation (IMF) while the other group (n =
13) where threated without skeletal elastic IMF.
Results: The mean
advancement at B-point and Pog in the skeletal elastic IMF group was 6.44 mm and
7.22 mm, respectively. Relapse at follow-up at B-point was -0.74 mm and -0.29 mm
at Pog. The mean advancement at B-point and Pog in the no skeletal elastic IMF
group was 6.30 mm and 6.45 mm, respectively. Relapse at follow-up at B-point was
-0.97 mm and -0.86 mm at Pog. There was no statistical significant (P > 0.05)
difference between the skeletal IMF group and the no skeletal group regarding
advancement nor relapse at B-point or Pog.
Conclusions: Bilateral
sagittal split osteotomy is characterized as a stable treatment to correct Class
II malocclusion. This study demonstrated no difference of relapse between the
skeletal intermaxillary fixation group and the no skeletal intermaxillary
fixation group. Because of selection-bias and the reduced number of patients it
still remains inconclusive whether to recommend skeletal intermaxillary fixation
or not in the prevention of relapse after mandibular advancement.
Objectives: Odontogenic keratocysts (OKCs) are developmental
cysts that have been reclassified according World Health Organization
(WHO), to keratocystic odontogenic tumours (KCOTs), a term that better
reflects their neoplastic nature. The aim of present study is to
evaluate the induction of stress of the endoplasmic reticulum and
execution of the resulting unfolded protein response in keratinocystic
odontogenic tumours.
Material and Methods: We analyzed by
immunohistochemistry the expression of the chaperones BiP/GRP78 and calnexin in
24 cases of KCOTs. As controls, we have used 9 cases of periapical or radicular
cysts (PACs) and 5 cases of Fibromas (FBs). The PACs and the FBs were included
in the analysis, as PACs are the most common type of inflammatory odontogenic
cysts of and FBs, as lesions of the connective tissue with unaffected
epithelium.
Results: Analysis revealed a strong association between
both BiP/GRP78 and calnexin expression and KCOTs: 18 out of 24 (75%) KCOTs
expressed BiP/GRP78 as opposed to 1 out of 9 (13%) PACs, and none of 5 FBs
evaluated (P < 0.001, x2-test). Calnexin was expressed in 11 out of
24 KCOTs (46%) but only one out of 9 (13%) PACs, and none of the 5 FBs analyzed
(P < 0.001, x2-test).
Conclusions: Study results imply
that induction of endoplasmic reticulum stress maybe of diagnostic value in
keratocystic odontogenic tumours characterization. In addition to recent
findings suggesting that endoplasmic reticulum stress plays a causative role in
keratinization of epithelia, pharmacological interference with the execution of
the unfolded protein response should be considered for the management of
keratocystic odontogenic tumours.
Objectives: The purpose of the present study was to
investigate factors affecting the formation, severity and location of
white spot lesions in patients completing fixed appliance therapy.
Material and Methods: A total of 45 patients (19 males and 26 females, mean
age 15.81 years, standard deviation 2.89 years) attending consecutively Aberdeen
Dental Hospital (ADH) between January and June 2013 to have their fixed
appliances removed were given a questionnaire to elicit information regarding
their dental care and diet. They were then examined clinically as well as their
pre-treatment photographs to record treatment data and white spot lesion (WSL)
location and severity using a modified version of Universal Visual Scale for
Smooth Surfaces (UniViSS Smooth). Absolute risk (AR) and risk ratios (RR) were
also calculated.
Results: The incidence of at least one WSL
observed in patients was 42%, with males displaying a higher incidence than
females. The highest incidence of WSLs was recorded on the maxillary canines and
lateral incisors, and on the maxillary and mandibular premolars and first
molars. The gingival areas of the maxillary and mandibular teeth were the most
affected surfaces. Significant (P < 0.05) relationships were found between the
presence of WSLs and the following factors: poor oral hygiene (OH), males,
increased treatment length, lack of use of fluoride supplements, use of
carbonated soft drinks and/or fruit juices and the use of sugary foods. Poor OH
posed the highest risk of developing WSL (RR = 8.55).
Conclusions: 42% of patients have developed white spot lesions during fixed appliance
therapy. Various contributing risk factors were identified with the greatest
risk posed by a poor oral hygiene.
Background: Aberrations in the root canal anatomy are
clinically challenging for clinicians. Mandibular first molars usually
have 2 roots and 3 or 4 canals, but various combinations may exist. A
distal root with three canals is rare and its incidence in literature is
about 0.2 - 3%. As a diagnostic tool, cone-beam computed tomography
(CBCT) may be a better choice for diagnosis of extra roots or canals
comparing to conventional radiography.
Methods: An
endodontic management of a mandibular first molar with six canals was performed.
CBCT was used to confirm the diagnosis and to understand the morphology of the
canals.
Results: Evaluation of the axial and coronal slices of CBCT
images confirmed the presence of 2 roots and 6 canals. The distal root had four
distinct root canal orifices with two apical foramens, being described as type
XIV canal configuration.
Conclusions: Dentists should be aware of
unexpected canal morphology when performing endodontic treatment. The present
case demonstrated the use of CBCT in diagnosis and negotiation of extra canals
in a mandibular first molar.
Background: The literature on total alloplastic
temporomandibular joint (TMJ) reconstructions is encouraging, and
studies on total alloplastic TMJ replacements outcomes showed acceptable
improvements in terms of both pain levels and jaw function.
Nevertheless, some adverse events, such as heterotopic bone formation
around the implanted prosthesis, may occur. In consideration of that,
the present manuscript describes a case of heterotopic bone formation
around a total temporomandibular joint prosthesis, which occurred
several years after the implant.
Methods: The present manuscript describes a case of
heterotopic bone formation around a total TMJ prosthesis, which occurred
several years after the implant in patients, who previously underwent
multiple failed TMJ surgeries.
Results: Ten years after the surgical TMJ replacement to solve
an ankylotic bone block, the patient came to our attention again
referring a progressive limitation in mouth opening. A computerized
tomography showed evidence of marked heterotopic bone formation in the
medial aspects of the joint, where a new-born ankylotic block occupied
most part of the gap created by resecting the coronoid process at the
time of the TMJ prosthesis insertion.
Conclusions: Despite
this adverse event has been sometimes described in the literature, this is the
first case in which its occurrence happened several years after the
temporomandibular joint replacement. It can be suggested that an accurate
assessment of pre-operative risk factors for re-ankylosis (e.g., patients with
multiple failed temporomandibular joint surgeries) and within-intervention
prevention (e.g., strategies to keep the bone interfaces around the implant
separated) should be better standardized and define in future studies.