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I guess its time for
me to retire
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In t
mo
31%
percom
for
(Hi
Long term follow-up of periodontaltreatment indicates periodontal lesionsin the majority of patients will respondwell. The one exception to this seem to
be lesions in multi-rooted teeth thathave advanced into the furcation areabetween the roots. (Hirschfield 1978,McFall 1982, Goldman 1986)
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Bo
d
Furcus
ra
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Boo
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Furcation involvementsaccording to Glickman are
classified as grade I, grade II,grade III or grade IV.
Grshowmos
furca
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The bone defect is a cul de sacwith a definite horizontal bone
loss. Vertical bone loss may alsobe present. There is an openinginto the furca with a bony wall at
the deepest portion.
Thereinner
part roofradioon the
GRADE II FURCA
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Bone is lost across the wholewidth of the furcation so no boneis attached to the furcation roof.
radport
GRADE III FURC
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GRADE III FURCATION G
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Grade III furcation onmesial of first molar.
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CAT scan will allow crosssection views of interior offurca in 1 mm bucco palatal
slices.
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At time of surgery there is
advanced bone lossexposing the mesial furcawith bone loss extending all
the way to the distalfurcation
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Bone loss across the furcation isaccompanied with gingivalrecession at the furcation is
clinically visible.
GRADE IV FURC
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Classification based on the vertical component (TarnowDepending on the distance from the base of the defect to the roof of the furca
Subgroup A: vertical dimension of bone up to 1/3 rd of the interradicular dista
Subgroup B: vertical dimension of bone up to 2/3rd of the interradicular dista
Subgroup C: vertical destruction of bone beyond the apical 1/3rd
of the interr
Classification based on horizontal component (Hamp a
Degree I: horizontal bone loss of less than 3mm.
Degree II: horizontal bone loss of more than 3mm.
Degree III: through and through horizontal lesion.
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Furcation involvements haveanatomical factors that make it
difficult to carry out root planing,calculus removal and
degranulation.
C
in
Local anatomic factors in the treatment of furcatons:
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Local anatomic factors in the treatment of furcatons:
1. Root trunk length
The combination of root trunk length and the no. and configuration of roo
Furcal involvement in teeth with short root trunk length show less bone l
Once furcation is exposed teeth with short root trunk length are more acc
2. Root length
It is directly related to the quantity of the supporting apparatus of the toot
Teeth with short root trunks & long roots have greater amount of attachm
3. Root form:
The mesial roots of most mandibular 1st and 2nd molars and the mesiobuc
apical third.
Also the distal aspect of this root is heavily fluted.
These increase the potential for perforation during endodontics and comp
increased of vertical root fracture.
The size of the mesial radicular pulp may result in the removal of the maj
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4. Interradicular dimension:
Closely approximated roots can preclude adequate instrumentation during sc
Teeth with widely spaced roots present more treatment options and are more
5. Anatomy of the furcation:
The presence of bifurcational ridges, a concavity in the dome, and possible ac
surgical therapy, but also periodontal maintenance.
Odontoplasty to reduce or eliminate these ridges may be required during surg
6. Cervical enamel projections:
These are reported to occur on 8.6% to 28.6% of molars.
The prevalence is highest for mandibular and maxillary 2nd molars.
These can affect plaque removal, complicate scaling and root planing and m
periodontitis.
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Classifications of cervical enamel projections:
Grade 1: the enamel projections extends from the CEJ to the tooth towards th
Grade 2: the enamel projections approaches the entrance to the furcation. It d
componenet.Grade 3: the enamel projections actually enters horizontally into the furcatio
Cervical enamel projections as an etiologic factor in furcation involveme
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Cervical enamel projections as an etiologic factor in furcation involveme
Swan RH, Hurt WC.
Two thousand molars in 200 East Indian skulls were examined for the occur
The relationship between the enamel projections and furcation involvement
cervical enamel projections in molars was 32.6%. The incidence of cervical e
second molars showed the highest incidence of enamel projections (51.0%),
incidence was seen in the maxillary first molars (13.6%). Grade 1 enamel pro
projections occurred most frequently on the buccal surfaces of teeth.
There was a positive, statistically significant relationship between tooth surf
involved furcations.
However, no etiologic relationship was found between grade 1 projections a
relationship between bone and enamel projections.
The alveolar crest has a tendency to follow the outline of the enamel projec
membrane space accommodates the enamel projection as it extends toward th
projections are severe enough to approach or enter the furcation area (grades
these furcations.
Cervical enamel projection and intermediate bifurcational ridge correlat
http://www.ncbi.nlm.nih.gov/pubmed?term=%22Swan%20RH%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Hurt%20WC%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Hurt%20WC%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Swan%20RH%22%5BAuthor%5D7/31/2019 Fur Cations
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Cervical enamel projection and intermediate bifurcational ridge correlat
Hou GL, Tsai CC.
Graduate Institute of Dental Sciences, Kaohsiung, Medical College, Kaohsiun
In this study, the cervical enamel projection (CEP) and intermediate bifurcat
involvement (FI) was investigated.
Study samples consisting of 87 hopeless permanent mandibulars (56 first and
therapy, were randomly collected from the School's Dental Clinic. The furcal
probing, periapical radiographs, and inspection of ground tooth sections of ex
of molars with CEPs and/or IBRs were also analyzed.Probing depths (PD), clinical attachment loss (CAL), gingival index (GI), an
surfaces of molar furcal areas. Moreover, the relationships between the molar
analyzed using Student's paired t-test.
Based on those results, we can conclude the following: 1) among 87 molars
and bifurcational ridges, and the prevalence was greatest in mandibular first (
differences in mean PD, CAL, PLI, and GI between the molars with and with
mandibular first and second molars.
http://www.ncbi.nlm.nih.gov/pubmed?term=%22Hou%20GL%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Tsai%20CC%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Tsai%20CC%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Hou%20GL%22%5BAuthor%5D7/31/2019 Fur Cations
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Extracted upper molar withcalculus in roof of furcation.
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In lower molars there is often an
anatomical groove on the lateralaspect of the roots particularly the
mesial root.
Thin
ultradiamhanacc
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T f f i d f
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Treatment of furcation defects:
1. Therapy for early furcation defects: Class 1
These are amenable to conservative periodontal therapy.
As the pocket is suprabony and has not entered the furcation, oral hygien
Any thick overhanging margins, facial grooves, or CEPs are removed by
2. Therapy for furcation defects: Class 2 Shallow horizontal component with little vertical bone loss responds wel
This reduces the dome of the furcation and improves the gingival contour
3. Therapy for advanced furcation defects: class2-3
The development of significant horizontal component to one or more furc
the furca poses additional problems.
Nonsurgical therapy is usually ineffective and periodontal surgery, endod
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In this case grade II furcations
on the buccal and lingualwere treated with initial
therapy and then with flapand osseous surgery.
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Pre osseous surgery
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Pre osseous surgery
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Apical positio
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Post surge
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In this Grade two furca the bone defect is less
than 4 mm. Below the roof of the furca and so
resective osseous surgery is indicated.
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Bone has been removed to eliminate the
defect and to create a positive architecture
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The flap is apically positioned and
shaped to follow the bone contours
so that minimal post surgical pocketsare developed.
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In this furca there is deep
pockets and advanced bone
loss.
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The bone loss is such that the deepest part
of the defect is more than 4 mm. from the
roof of the furca. Regenerative procedures
are needed.
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Bio oss and Emdogain have been
used to fill the defect to the level of
the bone crest.
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The flap has been sutured at its
original level and Emdogain applied
to the space under the flap.
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More advanced bone loss is
treated with regenerativeperiodontal surgery.
In thloss pr
regpe
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Periosteal graft from palate
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Six months
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Advanced grade II to IV
furcations may be treated withroot resections.
In thbu
endospeci
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Root resection:
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oot esect o :
It may performed on vital or endodontically treated teeth. It is however pref
root(s).
if not possible the pulp should be first removed , the patency of the canals d
It is distressing to perform a vital root resection and to subsequently have an
inability to instrument the canal.
Indications of root resection are :
1. Teeth that are of critical importance to the overall dental treatment plan. E
prosthesis for which the loss of the tooth would lead loss of the prosthesi
2. Teeth that have sufficient attachment remaining for function. Molars with
unless the lesions have 3 bony walls, are not candidates for root amputati
3. Teeth which have no remaining predictable or cost effective method of therasuccessfully treated with endodontics but now present with vertical root fr
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4. Teeth in patients with good oral hygiene and low caries activity are suitable
These therapies can present a sizeable financial investment on part of the patie
overall treatment plan should always be considered and presented to the pa
Also root resection and hemisection are contraindicated in patients unable or u
Which root to remove and why?
1. Remove the root(s) that will eliminate the furcation and form a maintaina2. Remove the roots with greatest amount of bone and attachment loss. Teeth
candidates for root resection.
3. Remove the root which best contributes to the elimination of periodontal p
classIII buccal to distal furcation is adjacent to a 2nd molar with a 2 walled
the 2nd molar. The removal of the distobuccal root of the 1st molar allows t
bony defect and facilitates access for instrumentation and maintenance of t
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4. Remove the root with the maximum no. of anatomic problems such as sev
or multiple root canals.
5. Remove the root that least complicates future periodontal maintenance.
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In lower molars hemisection is
used and one or both roots areretained.
Th
tre
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Hemisection:
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Hemisection:
Hemisection is the splitting of a two-rooted tooth into two separate
bicuspidization as it changes the molar into 2 separtate roots.
It is most likely to be performed on mandibular molars with bucca
with root resection molars with severe interradicular and interprox
As mentioned earlier one or both of the roots may be retained . Thloss, root trunk and root length, ability to eliminate the osseous de
The anatomy of the mesial roots of the manbdibular molars often
to facilitate both endodontics and restorative dentistry.
Importance of the interradicular separation:
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p p
Narrow interradicular zones can complicate the surgical procedure. T
surgical procedure.
The retention of both roots can complicate the restoration of the tooth
provide an adequate an adequate embrasure between the two roots for
Therefore orthodontic separation of the two roots may be required to
This can result in the need for multiple procedures and an interdiscip
In such cases GTR or replacement by osseointegrated implants should
The root resection/hemisection procedure:
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The most commonly performed root resection is the distobuccal root of the m
after adequate anesthesia, a full thickness periosteal flap is raised.
Root resection in teeth with advanced bone loss reqires opening of both fac
access for proper visualization and instrumentation & to minimize trauma du
After debridement the resection of the root begins with the exposure of the
Endodontic therapy is typically performed either before or after root resecti
Endodontic complications (root fractures) have been cited as a reason for evtherapy.
A root from a maxillary molar and the associated portion of the crown supp
amputating just the root as it emanates apically from the crown. Greenstein c
Keough reviewed the technique of removing a root and its accompanying c
of the tooth as it emanates from the osseous crest. He advocated recontourin
architecture.
Modifying tooth structure in this fashion eliminates undercuts and has been of the altered tooth and prosthetic contours to allow increased access by the p
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Carnevale and others"2 reported a success rate of 95 percent for root resectiv
those advocated by Keough and Kastenbaum".
Proper selection of teeth, conservative endodontic access and the design of t
Determining whether the morphology of the tooth is amenable to root resect
trunk. This length can be defined as the distance between the cementoenamel
the opening of the furcation. A tooth with a long root trunk is less likely to ha
must traverse a longer distance before the roots separate.
When furcation involvement occurs on this tooth, however, successful resec
remaining roots may not be long enough for support. In addition, removing o
osseous contours would involve excessive osseous removal on the adjacent t
Teeth with short root trunks are more likely to have furcation involvement a
for the junctional epithelium to traverse, furcation involvement is more likely
prognosis is greatly improved. Radiographs can help determine the root trunk
Majzoub and Kon described tooth morphology after distobuccal root resecti
using the technique described by Keough
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using the technique described by Keough.
The root was sectioned through the coronal aspect of the tooth. The distobu
removed simultaneously, resulting in an elimination of all undercuts (a trisec
One of the parameters that the authors looked at was the distance between th
aspect of the root separation. They determined that the average value for this
consistently had a distance of 3 to 4 mm.
It is necessary to consider the advantage of surgical access and trisection th
location of the floor of the pulp chamber, and the most coronal aspect of roodetermine the feasibility of retaining the remaining portion of the tooth and p
Backman described four cases in which incomplete root resections were pe
amputation. The author commented that the initial surgical access may have
radiograph to determine the accuracy of root removal.
Newell examined 70 root-resected teeth and described faulty root resection
amputation technique had left subgingival, residual roots, furcal tips and/or l
Current thinking is that a confluence of the root to prosthetic crown contour
physiologically developed and emerge from the root with a zero-degree emer
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physiologically developed and emerge from the root with a zero degree emer
root morphology are less plaque-retentive than the contours of restored teeth
Root removal:There are two ways to remove the affected root: with or without the associat
accompanying portion of the crown, is referred to as a root amputation.
This can be done with a long fissure bur or diamond, with copious irrigation
portion intact except for the aperture associated with the entrance of the root
This area can be widened, and a restorative material such as amalgam can be
The reflection of a gingival flap often enhances access in root amputation p
"Trisection" is the term applied specifically to surgical excision of a maxilla
procedure is called a "hemisection" when performed on a mandibular molar.
Similar to the root amputation procedure, elevation of buccal and palatal mu
to the adjacent osseous structures.
A long fissure bur on a highspeed handpiece is placed along the lo
a cut is made.
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This cut is channeled toward the center of the tooth and then direc
affected root. The cuts are made essentially over the portion of the
When viewed occlusally, a C-shape typically appears as the cut is
The bur is moved from the interproximal opening toward the bucc
moved apically toward the furcation area. Once the bur severs the f
remaining portion of the tooth.
The bur must not be extended apically to the floor of the pulp cham
structures are recontoured as needed after the root is removed and d
The severed portion of the root can be removed with a periosteal e
The remaining portion of the root is barreled in to remove any ledg
detrimental to periodontal maintenance.
Osseous recontouring.When odontoplasty is completed, osseous therapy can begin. The practition
restorative margin and the osseous crest and create positive osseous architec
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restorative margin and the osseous crest and create positive osseous architec
teeth.
Positive osseous architecture can be described as the topographic arrangem
(interproximal bone) is coronal to the level of the radicular osseous tissue, f
High-speed rotary instrumentation with copious amounts of water can elim
contours on the proximal surfaces and flat contours in the interproximal are
When this has been completed, the osseous crest on the proximal surfaces w
There will be a minimum of 3 mm from the floor of the pulp chamber to thcrest. Two of those millimeters allow for establishment of the supracrestal a
placement of the crown margin. If the remaining root trunk-the distance fro
wide enough, additional tooth structure will be obtained through osseous re
epithelial attachment and the crown margin. A minimum of at least 0.5 mm
Clearly, reflection of flaps and surgical access provide not only for proper o
the distance between the floor of the pulp chamber and the separation of the
undercuts.
Repositioning of gingival flapsThe aforementioned measurements are of great concern if prosthetic treatme
concept is used, a minimum distance of about 2 mm is needed between the os
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concept is used, a minimum distance of about 2 mm is needed between the os
restorative margin.
One millimeter would account for the supracrestal fibrous insertion into the
attachment of the junctional epithelium according to the average measuremen
Even though these average measurements might allow establishment of the s
still be in close proximity to the junctional epithelial attachment. In theory, ho
violated.
Certainly, an increased tooth structure would be beneficial so the restorativemost coronal aspect of the junctional epithelium.
No definitive scientific study, however, has documented the need to establish
to the editor of The Journal of Periodontology,27 pointed out that the range o
range for the connective tissue attachment was 0.00 to 6.52 mm in Gargiulo a
extrapolations made from that article which are utilized as guidelines for perf
and the connective tissue attachment measurements could be as low as 0.08 m
individual patient might have a perfectly healthy periodontium with very littl
If the cut passes through a metallic restoration it is cut before raising the fla
If a vital resection is to be performed a more horizontal cut is preferred as it
There is increased incidence of post operative pain.
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There is increased incidence of post operative pain.
Though a horizontal cut may complicate root removal it is associated with l
The root stump can be removed by odontoplasty after the completion of the
After resection the root is done care should be taken not to traumatize the b
Removal of the root facilitates the debridement with hand, rotary or ultrason
If necessary odontoplasty is performed to remove any developmental groov
impede its removal.
Patients with advanced bone loss commonly have other procedures combinbe treated with resective or regenerative surgeries.
After resection the flaps are re-approximated and made to cover any grafted
Sutures are then given to maintain the flaps in their position and the area m
The removal of a root alters the occlusal forces on the remaining roots &
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The removal of a root alters the occlusal forces on the remaining roots &
adjustments is required.
Centric holds may be maintained but eccentric forces are eliminated. Pati
the resected root to prevent movement.
Prognosis for root resection and hemisection:
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g
Earlier it was believed that a significant furcal defect dee
prognosis. However recent clinical trials have shown tha
thought if one prevent the development of caries in the fu
procedures are enough to maintain these teeth in function
Recent data indicates that recurrent periodontal disease i
The key to long term success appear to be thorough diag
hygiene, and careful surgical and restorative treatment.
R ti
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Regeneration:
Furcation defects with deep 2-walled and 3-walled defects are candidates fo
These vertical bony deformities are respond favorably to a variety of other s
membrane and bone grafts.
Various regenerative procedures include:
a. Autogenous bone grafts, e.g. osseous coagulum, bone blend.b. Allogratfs, e.g. FDBA, DFDBA.
c. Alloplasts, e.g. hydroxyapatite, tricalcium phosphate.
d. Citric acid root conditioning with coronally placed flap.
e. Guided tissue regeneration and combination techniques.
For grade III and IV furcation involvements the success is limited.
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In cases with advanced grade IIIinvolvement it may be
necessary to extract the toothdue to its very poor hopeless
prognosis.
Extraction:
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The extraction of a tooth with through and through defects and advanced
This is particularly true for patients who cannot or will not perform adequ
socioeconomic factors or other factors that preclude more complex therapi
Some patients are reluctant to accept periodontal surgery or even extractio
the long term prognosis is poor.
The patient may elect to forego therapy and opt to treat the area with scalthe tooth becomes symptomatic.
Although additional bone loss may occur but it is not uncommon for thes
The advent of osseointegrated implants as an alternative abutment source
furcation defects.
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Tunnel preparation:
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It is by transforming grade II furcation to a grade III & IV for better access
root caries.
Supportive periodontal care for teeth with furcation defects:
Scaling, root planing and other conventional periodontal therapy can be com
- doxycycline hyclate 10%) has been shown to show a short term increase i
Supportive periodontal therapy of furcation sites: non-surgical instrumeDannewitz B, Lippert K, Lang NP, Tonetti MS, Eickholz P.
Section of Periodontology, Department of Conservative Dentistry, Clinic for
http://www.ncbi.nlm.nih.gov/pubmed?term=%22Dannewitz%20B%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Lippert%20K%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Lang%20NP%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Tonetti%20MS%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Eickholz%20P%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Eickholz%20P%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Tonetti%20MS%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Lang%20NP%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Lippert%20K%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Dannewitz%20B%22%5BAuthor%5D7/31/2019 Fur Cations
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gy, p y,
Heidelberg, Heidelberg, Germany.
OBJECTIVES: Evaluation of the clinical effect of topical subgingival applic
(SRP) at furcation sites during supportive periodontal therapy (SPT).
MATERIAL AND METHODS: In 39 SPT patients exhibiting at least four po
pockets > or m. Additionally, 14% doxycycline gel was applied subgingivally
parameters were assessed at baseline, 3, 6, and 12 months after therapy. Addi
(3 months) improvement of furcation involvement and influence on the frequRESULTS: A total of 323 furcation sites (class 0: 160; class I: 101; class II: 1
SRP&DOXY resulted in better improvement of furcation involvement than S
SRP&DOXY failed to show a significant difference between both groups in
CONCLUSION: Single subgingival application of doxycycline in addition to
it failed to reduce the frequency of re-instrumentation up to 12 months at furc
REFERENCES:1. Clinical Periodontology- Newman, Takei, Carranza
2 E ti l f Cli i l P i d t l d P i d ti Sh ti i
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2. Essentials of Clinical Periodontology and Periodontics- Shantipriya
3. J Am Dent Assoc 1997;128;449-455 : A review of root resective therap
by T Hempton and C Leone
4. J Am Dent Assoc. 1976 Aug;93(2):342-5 Cervical enamel projections
by Swan RH, Hurt HC
5. J Periodontol. 1997 Jul;68(7):687-93. Cervical enamel projection and
furcation involvementsby Hou GL, Tsai CC
6. J Clin Periodontol. 2009 Jun;36(6):514-22. Supportive periodontal the
without topical doxycyclineby Dannevitz B, Lippert K