FINAL Flashcards
(210 cards)
1
Q
Odontogenic Keratocyst (OKC) managmenet
A
- E&C with poten7al extrac7on
- If larger – consider staged marsupializa7on and E&C
2
Q
pt presents with established MRONJ
A
Consult and Refer!!!
3
Q
allograft and xenograft have what type of potential
A
Osteoconductive
4
Q
Marsupializa*on • Disadvantages
A
– Cannot histologically examine the en7re cys7c wall
• Areas leI behind may be more aggressive than
piece removed
– Pa7ent inconvenience with home care
– Occasional secondary infec7ons
5
Q
correct vertical periodontal defects
A
orthodontic eruption
6
Q
Residual cyst management
A
Residual
• E&C
7
Q
bone infection
A
osteomyelitis
8
Q
removing a known aggressive cyst such
as an OKC (high recurrence) use what procedure
A
Enuclea*on & cure1age
9
Q
3. Lateral periodontal cyst
managment
A
• Enuclea7on with preserva7on of tooth
10
Q
Treatment of choice for cystic lesions
A
- Enucleation
11
Q
three phases during distraction osteogenesis
A
latency
distraction
consolidation
12
Q
A condition in which Irradiated bone becomes
exposed through a wound in the overlying
skin and/or mucosa and persist without
healing for 3 to 6 months
A
osteo-radio-necrosis
13
Q
Known as “ decompression” technique
A
Staged marsupializa*on & enuclea*on
14
Q
how to examine functional load in TMJ area
A
bite tongue blade between most
posterior teeth bilaterally and incisors
15
Q
taking PO oral bisphosphonates
A
Informed consent/Medical
consult if considering drug holiday!
16
Q
Asymptomatic patient receiving IV therapy
for bisphosphonates
A
§ Maintain oral hygiene § Avoid osseous injury
17
Q
treatment sequence for internal derangement of TMJ
A
arthrocentesis
arthroscopy
open surgery
18
Q
Member of the cytokine family of growth factors
A
BMP (Bone Morphogenic Protein)
19
Q
Enuclea*on • Disadvantages
A
– Possible pathological fracture
– Devitaliza7on of teeth
– Injury to nerve
20
Q
minimum distance between implant incisive canal
A
avoid midline maxilla
21
Q
indications for arthrocentesis
A
• Acute closed lock • Acute trauma (hemarthrosis) • Capsulitis/synovitis
22
Q
clinical stage 3 MRONJ treatment
A
§ Surgical debridement or
resection § Antibiotic therapy
23
Q
A true cyst contains an
A
A true cyst contains an epithelial lining
24
Q
A
25
what type of implants can be used to avoid the sinus
angled implants
26
surgically lengthen bone
distraction osteogenesis
27
New bone formation from differentiation of
osteoprogenitor cells, derived from mesenchymal
cells, into osteoblasts.
Osteoinduction
28
– Any cyst that can be removed in en7rety & safely
without harming adjacent structures should use what procedure
Indica7ons
29
Palpation – general principles
Light pressure over
Light pressure over lateral capsules: 5 lbs.
30
intraroral donor sites for block grafting
chin and ramus
31
two methods of horizontal augmentation
guided bone regeneration
block grafting
32
Tricks to detect guarding (excessive limitation
of ROM)
during TMJ exam
– Observe during interview, note interincisal ROM
– Look for tonsillar hypertrophy with tongue blade
33
performed through the implant osteotomy when you want to place an implant but need a few additional mm of bone
indirect sinus augmentation
34
increased risk of graft/membrane exposure
concern with vertical augmentation by grafting
35
vertical augmentation of the sinus predictable/non predictable
very predictable (posterior maxilla area)
everywhere else have to use distraction osteogeneiss or orthodontic eruption
36
Enucleation & Curettage of Jaw Tu m o r s
in what tumors specifically (4)
• Odontoma
• Ameloblas7c fibroma/
fibro-odontoma
* AOT
* Cementoblastoma
* Odontogenic fibrom
37
name a source of autograft that has no long term morbidity and has no issues on pt function right after
no long term morbidity, no issues walking right after, no gait disturbances, a little scar-anterior iliac crest
38
clinical stage 1 treatment
§ Oral antimicrobial rinses
(e.g. Peridex)
39
horizontal augmentation for small, well-defined, concave defects
guided bone regeneration
40
Staged marsupializa\*on & enuclea\*on • Lesion marsupialized and allowed time for:
– Bone cover of vital structures
– Increased strengthening of jaw
41
– Best for internal derangement, effusion
MR
42
Preauricular tenderness may be either
joint or muscle
finding
43
Aggressive lesions either by
histopath or clinical behavior
tx
Resection of Jaw Tumor
44
diseases associated with bone healing problems
drug related osteonecrosis of the jaws
osteo-radio-necrosis
osteomyelitis
45
like a catch, but stays that way for
minutes, hours, days, etc.
in TMJ area
Limited/Impaired movement
– Closed lock
46
BMP-2=Infuse® Not approved in
Not approved in children/skeletally immature
patients
47
Marsupializa\*on • Indica7ons
– Adjacent vital structures at risk with enuclea7on
– Difficult surgical access to all por7ons of cyst
• Increases recurrence rate
– Medical compromise
48
Palpation – general principles
– Moderate pressure
Palpation – general principles
– Moderate pressure over masticatory muscles: 10 lbs.
49
controlled displacmeent of surgically created fractures
distraction osteogenesis
50
what happens during the latency stage of distraction osteogenesis
revasculariztion
osteoprogenitor cells accumulate
51
Does not actually produce bone – conducts bone
forming cells from host into/around the scaffolding.
Osteoconduction
52
full-thickness por7on removed resection technique
Segmental –
53
• Most odontogenic
tumors tumors tx
Enucleation & Curettage of Jaw Tu m o r s
54
Local removal of the tumor by instrumenta7on
or direct contact with the lesion
Enucleation & Curettage Surgical Te c h n i q u e
55
Removal of the disk
Meniscectomy=Discectomy:
56
how long does the conslidation phase occur in distraction osteogenesis
2-3 months
57
Enuclea\*on & cure1age • Advantage
– Destroys any suspected epithelial remnants,
decreasing chance of recurrence
58
Total Joint Replacement • Indications
• Severe degeneration, usually mostly of the condyle
• foreign body giant cell reaction
• rheumatoid arthritis
• Juvenile Idiopathic Arthritis
• Idiopathic condylar resorption • Recurrent fibrous or bony ankylosis • Failure of other reconstructive procedure, e.g.
costochondral graft
59
PHASE I
Transplanted cellular bone in bone grafts produces new
Transplanted cellular bone produces new osteoid.
60
why does MRONJ happen in the jaws
¡ Increased bone turnover in the jaws
(Remodeling rate is 10 times more than long
bones )
¡ Thin overlying oral mucosa due to jaw
anatomy.
61
Removal of the en7re cys7c lesion without rupture
. Enuclea\*on
62
requires a "good root" with a non-restorable crown
orthodontic eruption
63
minimum distance between implant and natural tooth
2mm
64
minimum distance between implant and mental nerve
5mm from anterior of bony foramen
65
Formation of new bone from either host-derived or
transplanted osteoprogenitor cells along a biologic
framework.
Osteoconduction
66
how to palpate the temporalis insertion
Palpate posterior maxillary vestibule
Posterior on ascending ramus
67
how long do you leave the cavity open with marsupialization
Un7l goals for choosing marsupializa7on have
been met
68
BMP (Bone Morphogenic Protein)
is higher in what type of bone
Higher in cortical bone vs. cancellous.
69
mechanical obsturction in TMJ area can mean
internal derangement
arthropathy
70
three things we are concerned about with jaw tumors
• Lesion behavior • Anatomic loca7on • Desired reconstruc7on
results
71
indicated for inadequate vertical dimension
sinus augmentation
72
Cadaver bone
Allografts/Homografts
73
Special Challenges to Advanced Implant Placement
Immediate Placement
Posterior mandible
Atrophic maxilla
Pathology ablation
74
minimum distance between implant and infeirior bordre of md
1mm
75
• Muscle palpation
in TMJ area
– Work from top down, starting at temporalis crest
• Temporalis, masseter • Repeat for SCMs, posterior neck/trapezius
76
how long for bony fill in enucleation
6-12 months
77
Inspection
clinically in TMJ area
– Facial asymmetry
– Swelling
– Asymmetric facial movement
– Masticatory muscle hyperplasia, hyperactivity
78
Resection of Jaw Tumors
name specific tumors
• Ameloblastoma • Myxoma • CEOT • Squamous odontogenic tumor
79
only _____ grafts are capable of osteogenesis
Osteogenesis
80
Consider \_\_\_\_\_\_\_\_\_\_in highly sensitive patients in TMJ area
Consider neuropathic pain (e.g. tactile allodynia,
hyperalgesia) in highly sensitive patients
81
new bone forms in gap
distraction osteogenesis
82
name 3 oral bisphosphonatets
¡ Fosamax (alendronate)
¡ Actonel (risedronate)
¡ Boniva (inandronate)
83
Synthetic analogs of inorganic pyrophosphate
bisphosphoantes
84
put a suture in the tissue and leave it open to the oral cavity and let it burst on its on
Marsupializa\*on
85
\_\_\_\_\_\_\_\_\_\_grafting for replacement of TMJ
Costochondral grafting for replacement of TMJ
86
Localized involvement with involvement of cortical and medullary bone
treatment
stage 2 osteoradionecrosis
Conservative : Local debridement w,w/o HBO Chlorhexidine MW
87
• Cyst is enucleated first
• Mechanical (burs) cure]age is performed to remove
1-2mm of bone at the en7re periphery of the bony
cavity
2. Enuclea\*on & Cure1age (E&C)
88
soft tissue envelope expands
distraction osteogenesis
89
Ectomesenchymal
tumors
1. Odontogenic fibroma 2. Odontogenic myxoma 3. Cementoblastoma
90
allows our bones to repair from daily micro-trauma
bone remodeling
91
barrier isolates the defect from surrounding soft tissue
guided bone regeneration
92
asymptomatic pt still taking oral BP \<4 years + risk factor (sterior/angiogenic meds)
stop BP therapy 2 months prior to treatment
93
clinical stage one MRONJ
§ Exposed/necrotic bone § Asymptomatic § No infectio
94
TMJ/MPD pain may trigger
migraines
95
Tumors that would be
difficult to remove in
en7rety by enuclea7on/
cure]age alone
tx
Resection of Jaw Tumors
96
what is tyrosine
anti-angiogenic medications
97
Initiates osteoinduction.
BMP (Bone Morphogenic Protein)
98
pathogenesis of osteoradionecrosis
¡ Hypoxia ¡ Hypovascularity ¡ Hypocellularity
99
minimum distance between implant and inferior alveolar canal
2mm from superior aspect of bony canal
100
does vertical or horizontal have a greater resorption rate
vertical
101
what muscles in the TMJ area are not **are not directly palpable**
Pterygoid muscles
102
inter-implant distance
3mm between outer edge of implants
103
Have osteoinductive and conductive properties.
Osteogenesis
104
what is really important before doing an extraction
Ta ke thorough medical history before performing teeth extraction !!!
105
Slow-growing, non-
aggressive tumors tx
Enucleation & Curettage of Jaw Tu m o r s
106
Determines quality of bone
Two-Phase Theory of Osteogenesis
PHASE II
107
what radiographic findings are seen with osteomyelitis
moth eaten appearance
radio opacities -? sequestra
108
Methods to restore lost tissue volume
Grafting
Distraction
Orthodontic Eruption
109
Types of Bone Grafts
Autograft
2. Allograft
3. Xenograft
4. Alloplast
5. Recombinate graft
110
Opening cyst to oral cavity
marsupializa7on
111
Name Developmental Cysts Developmental
Developmental
– Den7gerous Cyst
– Odontogenic Keratocyst (Tumor – WHO)
– Lateral Periodontal Cyst
– Glandular Odontogenic Cyst
– Calcifying Odontogenic Cysts (Gorlin’s Cyst)
112
Arthrocentesis Advantages
• Minimally invasive • Fast, simple procedure – usually done in office • Does not require general anesthetic • Highly effective at increasing joint mobility, reducing pain
113
BMP in young children can cause
cancer
114
Determines quantity of bone that the graft will form.
Two-Phase Theory of Osteogenesis
PHASE I
115
Provide only passive framework or “scaffolding.”
Osteoconduction
116
treatment for osteomyelitis
antibiotics-clindamycin
hospitization
117
Two-Phase Theory of Osteogenesis
PHASE I
is most active when
Most active within 4 weeks.
118
when is block grafting ready for implant placement
4-6 months
119
MANAGEMENT OF CYSTS (4)
1. Enuclea7on
2. Enuclea7on & cure]age (E&C)
3. Marsupializa7on
4. Staged marsupializa7on & enuclea7on
(decompression technique)
120
General
– Posture, body habitus, mood, affect, insight
• Note distinctives, in TMJ evaluation
“poor eye contact, spoke through
clenched teeth throughout interview,” etc.
121
An inflammatory process of the bone marrow that involves cancellous and cortical bone with a tendency of progression.
osteomyelitis
122
drug holidays are effective for bisphosphonates T./F
false While there have been limited studies on drug holidays for treatment of MRONJ, currently there have yet to be studies to confirm drug holidays are effective in prevention of MRONJ without increasing the skeletally related risks of low bone mass.
123
correct uneven osseous/gingival levels
orthodontic eruption
124
Recominate Bone Morphogenic proteins (BMP-2 and
BMP-7 have FDA approval)
Recombinate Grafts
125
what is an all on four
2 angled parallel to sinus wall
2 in anterior
126
name a good mnemonic for evaluating TMJ in pain history
L Location of the symptom (finger vs. hand) I Intensity of the symptom (scale 1-10)
Q Quality of the symptom (e.g. burning, pulsating,
ache) O Onset of the symptom + precipitating factors R Radiation of the symptom (“show me where”)
A Associated symptoms (joint sounds, other
neurological oddities) A Alleviating factors (avoid jaw function, etc.) A Aggravating factors (chew, sing, talk a long time)
127
Staged marsupializa\*on & enuclea\*on • Advantages
– Develops a thickened cys7c lining
– Reduces morbidity and accelerates complete healing
– Same as for marsupializa7on
• Simple to perform • Can save vital structures • Completely resolves lesion or makes it smaller and easier to
treat and reconstruct
128
Formation of new bone from osteoprogenitor cells.
Osteogenesis
129
clinical stage 2 MRONJ treatment
§ Oral antimicrobial rinses § Antibiotic therapy
130
protrusion in TMJ translates
both joints
131
Epithelial
tumors (4)
1. Ameloblastoma
2. Adenomatoid odontogenic tumor
3. Calcifying epithelial odontogenic tumor (Pindborg)
4. Squamous odontogenic tumor
132
– A screen for gross joint pathology and other
potential problems for TMJ eval
Panoramic Film
133
Decreases intracys7c pressure
Marsupializa\*on
134
three ways to vertically augment bone
distraction osteogenesis
orthodontic eruption
sinus augmentation
135
Superficial involvement, only Cortical bone exposed
treatment?
stage 1 osteoradionecrosis
Conservative : Chlorhexidine MW
136
dry socket shoud not last longer than what
Dry socket does not last for more than a
week. Think something else!!! - REFER (could be osteomyelitis)
137
Enuclea\*on • Advantages
– Histopathologic examina7on of the en7re cys7c
wall
– Ini7al biopsy/treatment is cura7ve in certain
situa7ons
138
Mixed epithelial & ectomesenchymal
tumors
1. Ameloblas7c fibroma
2. Ameloblas7c fibro-odontoma
3. Odontoma
139
Repair, revision, and/or
reconstruction of joint tissues (hard and soft)
Arthroplasty:
140
how much bone is produced in the distraction phase of distraction osteogensis
1mm per day
141
is horizontally augmentating ridges predictable or not predictable
• horizontally augmenting ridges: predictable
142
Staged marsupializa\*on & enuclea\*on • Indica7ons
– Concern for injury to adjacent anatomical
structures
– Size of lesion
– Marsupializa7on alone does not resolve lesion
– Need to examine en7re lesion histopathologically
143
BMP-2=Infuse® has been approved for
BMP-2=Infuse® has been approved for sinus floor augmentation and grafting of mandibular defects
144
name 3 IV bisphosphonates
¡ Aredia (pamidronate)
¡ Zometa (zolendronate)
¡ Reclast (zolendronate)
145
– Press upward from when palpating the muscles in the TMJ area
– Press upward from pterygomandibular sling, note
radiation or distant site of pain (e.g. TMJ area,
whole side of head)
146
what happens in the consolidation phase during distraction osteogenesis
active distraction complete
bony regenerate remodels into mature bone
147
clinical stage 3 MRONJ
§ Exposed/necrotic bone
§ Pain
§ Infection
§ One or more of the
following: ▪ Fracture, extra-oral fistula,
oro-nasal communication.
osteolysis
148
augment horizontal dimension of alveolus
block grafting
149
Open a cys7c lesion and maintain patency to an
adjacent cavity
Marsupializa\*on
150
Extremely limited, unchanging ROM may indicate
in TMJ area
ankylosis
151
drugs associated with MRONJ
1) bisphosphonates
2) anti-resorptive agents
3) anti-angiogenic medicatiosn
kinase inhibitors and monoclonal antibodies
152
vertical augenting ridge predictable or non
nonpredictable
153
Differentiation is influenced by bone inductive
proteins from the bone matrix.
Osteoinduction
154
why is it difficult to obtain vertical augmentation
due to pressure from soft tissue envelope or a prosthesis
155
Calcifying odontogenic cyst (Gorlin’s) managmenet
• Enuclea7on and cure]age
156
Enuclea\*on & cure1age Disadvantage
Damage to neurovascular bundle
– Dental pulps stripped
157
Allografts/Homografts
have what type of graft
Osteoconductive
158
extraoral donor site that provides a large quantity of bone
iliac crest
159
Staged marsupializa\*on & enuclea\*on • Disadvantages
Same as for marsupializa7on
• Pa7ent inconvenience • Occasional secondary infec7on • Cannot histologically examine the en7re cys7c wall
– However, secondary enuclea7on can remedy this concern
160
– maintains con7nuity at inferior
border resection technique
Marginal
161
Fibrous connec7ve 7ssue (CT) wall allows a cleavage
plane between lesion and bony cavity
1. Enuclea\*on
162
inadequate adaptation and/or fixation of the bone graft to recipient bed
concerns with vertical augmentation by grafting
163
how to palpate the masseter origin
Palpate posterior maxillary vestibule
• Lateral/posterior
164
Remodeling process continues indefinitely.
Two-Phase Theory of Osteogenesis
PHASE II
165
in enucleation use the largest curette that will allow
* Cleavage plane
* Concave surface toward bone
166
stage 2 MRONJ
§ Exposed/necrotic bone § Pain § Infection
167
zygomaticus implants are placed where
through the palatal aspect of the maxillary crest transantrally into the compact bone of the zygoma
168
iv indications for bisphosphonate rlated osteonecrosis of the jaws
IV ¡ Bone metastases associated with solid
tumors
¡ Hypercalcemia of malignancy
¡ Multiple myeloma
169
what is denosumab
anti-resorptive agent
170
Indications for Arthroscopy
Indications for Arthroscopy • Pain and dysfunction with the following conditions:
• Decreased condylar translation due to disk hypomobility • Anteriorly displaced disk with or without reduction • Closed lock • Traumatic injury
171
how should monitor after enculeation ( in general practitioner office)
May require close follow-up with periodic panoramic
radiograph (every 6 months)
172
general stiffness in TMJ area can mean
muscular influences
173
Opening cyst to oral cavity (marsupializa7on) and
surgical plan is to make the cyst smaller (decompression) for final E&C at a later date
Staged marsupializa\*on & enuclea\*on
174
• Second surgery after recurrence when 1st
surgery (enuclea7on) was deemed cura7ve use what procedure
Enuclea\*on & cure1age
175
Two-Phase Theory of Osteogenesis
PHASE II
begins
Begins at 2 weeks and peaks around 6 weeks.
176
diagnosis of MRONJ
Ø Current or previous treatment with a
bisphosphonate
Ø Exposed bone in the maxillofacial region that
has persisted for more than Eight weeks
Ø No history of radiation therapy to the jaws
177
Inflammatory 1. Periapical
cyst management
* Remove underlying process – RCT or extrac7on
* Enucleate +/- cure]age
* An7bio7cs if necessary
178
bSynthetic analogs of inorganic pyrophosphate How do they work?
¡ High affinity --------
¡ Inhibition of -------
¡ May inhibit ---------
Synthetic analogs of inorganic pyrophosphate How do they work?
¡ High affinity for Ca2+
¡ Inhibition of osteoclasts
¡ May inhibit capillary neo-angiogenesis
179
Name 2 Inflammatory cysts
– Periapical Cyst – Residual Cysts
180
Glandular odontogenic cyst
managmenet
* Enuclea7on and cure]age
* Some advocate more aggressive treatment (resec7on)
181
post-op care after bone grafting
diet mods
temporary prosthesis-non load bearing/limit wear
oral hygiene
182
oral indications for bisphosphonates
osteoporosis/osteopenia
paget's disease
osteogenesis imperecta
183
Den7gerous cyst
managment
* Extrac7on of affected tooth + E&C
* If larger – consider staged marsupializa7on and E&C
184
what is enucleation good for
– Den7gerous cyst
– Periapical cyst
185
Two-Phase Theory of Osteogenesis
PHASE II
\_\_\_\_\_\_\_\_\_\_ is resorbed and replaced by \_\_\_\_\_\_\_\_\_\_. As the initial graft is resorbed, \_\_\_\_\_\_\_\_\_\_are released from the matrix.
Initial woven bone is resorbed and replaced by lamellar
bone. As the initial graft is resorbed, bone morphogenic proteins are released from the matrix.
186
receiving IV bisphosphonates
Avoid osseous surgery if
possible!
187
minimum required distance between implant and indicated struction for buccal + lingual plate
1mm
188
– Indirect load to lateral pterygoids
indicates what when examining the TMJ area
• Press chin area posteriorly and/or superiorly against
resistance with mouth half open (half of patient’s best
opening)
Note presence of pain in preauricular area (TMJs) or
deep under cheekbone (lateral pterygoid)
189
tx of tumors in medically compromised pts
Enucleation & Curettage of Jaw Tu m o r s
190
– Best for suspected bony abnormality, i.e.
ankylosis, severe arthritis
CT
191
Effusions in TMJ joint are strongly associated with
Effusions are strongly associated with ADD (+/-
reduction) and pain
192
```
Sole treatment (rarely) or as a preliminary step
before defini7ve enuclea7on of the smaller cyst
```
Marsupializa\*on
193
Asymptomatic patient taking oral BP \> 4 years
: Drug holiday for 2 months.
194
In osteoinduction, host cells must be stimulated to differentiate into the _______ by ______ and \_\_\_\_\_\_.
Host cells must be stimulated to differentiate into the
osteoblasts by transplanted growth factors and
cytokines.
195
Incision into the joint
Arthrotomy:
196
Marsupializa\*on • Advantages
– Simple to perform
– Can spare vital structures
– Either completely resolves lesion or makes it
much smaller and easier to treat and reconstruct
197
The Gold Standard
of grafts
Autografts
198
Two-Phase Theory of Osteogenesis
PHASE II
___________________ from the
graft bed begin after grafting, and\_\_\_\_\_\_\_\_ from host connective tissue soon begins.
Angiogenesis and fibroblastic proliferation from the
graft bed begin after grafting, and osteogenesis from host connective tissue soon begins.
199
ADD is frequently found in asymptomatic control
populations what percent
(12-45%)
200
about to receive IV bisphosphonates
Get healthy before!
201
Does NOT demonstrate joint space reliably
Panoramic Film
202
Asymptomatic patient taking oral BP ¡ Sound recommendations are still lacking
§ \<4 years
proceed with planned treatment
203
common reasons of compromised wound healing
medications
radiotherapy
infection
systemic disease
204
minimum distance between implant and mx sinus/ nose
1mm
205
Diffuse involvement including inferior border. Usually associated with pathologic fracture and possible osteo-cutaneous fistula
treatment
stage 3 osteoradionecrosis
Surgical resection and reconstruction
206
what happens during the distraction phase of distraction osteogenesis
osteoblast induction
woven bone formation
207
¡ Patients about to begin IV therapy
for bisphosphonates how to manage
¡ Patients about to begin IV therapy
§ Delay therapy, if systemic conditions permit
§ Optimize oral health prior to initiating therapy
§ Allow adequate osseous healing and wait until the
surgery sites become mucosalized (14-21 days)
208
Grafts transplanted between individuals of different
species (i.e. bovine bone/Bio-Oss)
Xenograft
209
indirect sinus augmentation yields how much bone
4mm of bone
210
BMP (Bone Morphogenic Protein)
acts on _______ to induce differntiation into
Acts on progenitor cells to induce differentiation into
osteoblasts.
